prepare release of v1.6.0

Referer, target and user agent filter share most of their logic
for different matching methods. We introduce a common routine for
all of them to not repeat ourselves. Passing a value extractor by
reference allows lazy evaluation (filter might be disabled) and
overrides for different cases (i.e. domain extractor for exact match).

.gitattributes

@@ -0,0 +1,12 @@
+/assets export-ignore
+/test export-ignore
+.gitattributes export-ignore
+.gitignore export-ignore
+.travis.yml export-ignore
+composer.json export-ignore
+composer.lock export-ignore
+CONTRIBUTING.md export-ignore
+package.json export-ignore
+phpcs.xml export-ignore
+phpunit.xml export-ignore
+RoboFile.php export-ignore

.gitignore

@@ -0,0 +1,8 @@
+composer.lock
+/vendor/
+/node_modules/
+/dist/
+.idea
+tests-clover.xml
+tests-junit.xml
+.phpunit.result.cache

.travis.yml

@@ -0,0 +1,13 @@
+language: php
+php:
+  - '5.6'
+  - '7.3'
+  - '7.4'
+  - '8.0'
+before_script:
+  - composer install
+script:
+  - composer test-all
+notifications:
+  slack:
+    secure: "ScXTSMO65veI1jA6TBHGDUtvDqEMkqJykaNf7vLLbb7YIxPIHHNBiX/wcjOHVFfQXZCV3qxQrflB7Lbm9qVUsAv861jTO9x/ZkECl5QhRoc0DIznejwZoypx0HJ9tBZFYT6qNUkViXRKZ/ILAiBLU9Yw52WACtQB9hu3FNFZwmKsjipvV8Sne1qEyTkLYLaMphsbC5mtXYdKMHvdt39jsYsk91UWGeYbXQ37LkMbsaG/8YHXF724d5JO7BRGoThw6p5knKAO5fk29V7GfNqg2h+hnGyNIUOcmxujgMDMFLyFCGMZpPoBa+3jyWWgq4PgpQt0F5VZtJFGoXCGcoMQm5IbVfqkSKJ4jYhqiSIrqSebLmzoPHepWX3yn8tpfOiBWjC6K9w9esp6vcZf26rnAJcjcGkA01rMrHRwR+UEMCLvj7q0DR0qzi/AFeED6gtpODzUf93Rp42Tz1iGvWIbgeCtkCWjfPO6XLuNiqGVPEVaT5BDKqlqbijdKxxp7yh1fdt8s0fInWdIsgoWTbU9DC1W4ZiqtQW7oYO+QtFZMaD6kZWpSqJUwB3kW5JL3odAUEm8bLbRWBvK5ZjGdaGqSbOs6f9gAKcf86iQQhwzCJSOgFlLlKFv9smicjPC+BGOxgx32pgseHNPWn6tmEo/ihmmr/NbbqoOusUKX9gQbA4="

CONTRIBUTING.md

@@ -0,0 +1,132 @@
+# How to contribute
+
+As for all great Open Source projects, contributions in form of bug reports and code are welcome and important to keep the project alive.
+
+In general, this project follows the [GitHub Flow](https://guides.github.com/introduction/flow/). 
+Fork the project, commit your changes to your branch, open a pull request and it will probably be merged.
+However, to ensure maintainability and quality of the code, there are some guidelines you might be more or less familiar with. 
+For that purpose, this document describes the important points.
+
+## Opening an Issue
+
+If you experience any issues with the plugin or the code, don't hesitate to file an issue.
+
+### Bug Reports
+
+Think you found a bug?
+Please clearly state what happens and describe your environment to help tracking down the issue.
+ 
+* Which version of the plugin are you running?
+* Which version of WordPress?
+* Which version(s) of related plugin(s) (e.g. Statify)?
+* Which version of PHP and - if of interest - which webserver are you running?
+
+### Feature Requests
+
+Missing a feature or like to have certain functionality enhanced?
+No problem, please open an issue and describe what and why you think this change is required.
+
+## Pull Requests
+
+If you want to contribute your code to solve an issue or implement a desired feature yourself, you might open a pull request.
+If the changes introduce new functionality or affect major parts of existing code, please consider opening an issue for discussion first.
+
+For adding new functionality a new test case the corresponding PHPUnit test would be nice (no hard criterion though).
+
+The `master` branch should also be target for most pull requests.
+However it it features new functionality you might want to target the `develop` branch instead (see next section for details on branches).
+
+### Branches
+
+The `master` branch represents the current state of development.
+Please ensure your initial code is up to date with it at the time you start development.
+
+In addition, this project features a `develop` branch, which holds bleeding edge developments, not necessarily considered stable or even compatible.
+Do not expect this code to run smoothly, but you might have a look into the history to see if some work on an issue has already been started there.
+
+For fixes and features, there might be additional branches, likely prefixed by `hotfix/` or `feature/` followed by an issue number (if applicable) and/or a title.
+Feel free to adapt this naming scheme to your forks.
+
+### Merge Requirements
+
+To be merged into the master branch, your code has to pass the automated continuous integration tests, to ensure compatibility.
+In Addition your code has to be approved by a project member.
+
+#### What if my code fails the tests?
+
+Don't worry, you can submit your PR anyway. 
+The reviewing process might help you to solve remaining issues.
+
+### Commit messages
+
+Please use speaking titles and messages for your commits, to ensure a transparent history.
+If your patch fixes an issue, reference the ID in the first line.
+If you feel like you have to _briefly_ explain your changes, do it (for long explanations and discussion, consider opening an issue or describe in the PR).
+
+**Example commit:**
+```text
+Fix nasty bug from #1337
+
+This example commit fixes the issue that some people write non-speaking commit messages like 'done magic'.
+A short description is helpful sometimes.
+```
+
+You might sign your work, although that's no must.
+
+### When will it be merged?
+
+Short answer: When it makes sense.
+
+Bugfixes should be merged in time - assuming they pass the above criteria.
+New features might be assigned to a certain milestone and as a result of this be scheduled according to the planned release cycle.
+
+## Compatibility
+
+To ensure usability for a wide range of users, please take note on the software requirements stated in the `README`.
+This includes especially the minimum PHP version and also the minimum version of WordPress.
+
+If you are unsure if your code matches these versions, the test will probably tell you.
+
+In case you think, your change is more important than maintaining backwards compatibility, please start a discussion to see, 
+if we might increase the minimum version or find a workaround for legacy systems. 
+
+## Build Environment
+
+All you need to start off - besides your favorite IDE of course - is [Composer](https://getcomposer.org). 
+Running `composer install` will fetch all dependencies and build tools required. 
+You might have noticed that this project contains a [Robo](http://robo.li) build script.
+Running the _build_-task (`./vendor/bin/robo build`) executes the full chain from cleanup over test to bundling the final product in the `dist` directory.
+A complete list of the available tasks and options can be shown by running `robo list`.
+
+## Unit Tests
+
+The PHP code is tested by a PHPUnit tests.
+All test files are located in the `test` directory. 
+Files ending with `-test.php` will be automatically included into the test suite.
+The coverage is not yet perfect, but be invited to write tests for methods not yet covered or newly introduced by your patch.
+
+## Code Style
+
+This project, as part of the WordPress ecosystem adheres to the [WordPress Coding Standards](https://codex.wordpress.org/WordPress_Coding_Standards).
+Please make sure that you are at least roughly familiar with those guidelines.
+
+The code style is automatically checked for commits (including pull requests) using [PHP CodeSniffer](https://github.com/squizlabs/PHP_CodeSniffer).
+You can check your code against the configured ruleset yourself by running
+ `./vendor/bin/phpcs --standard=phpcs.xml your-edited-file.php` (assuming `composer install` has been executed) or the Robo task `robo test:cs` for a complete scan.
+
+Please see these standards as guidelines. 
+If code style this is the only test that fails and your code's semantics are fine, don't hesitate to submit your pull request anyway.
+We probably find a solution for that.
+
+## Continuous Integration
+
+Automated tests are run using [Travis CI](https://travis-ci.org/stklcode/statify-blacklist) for every commit including pull requests.
+They ensure compatibility with the supported PHP versions and the WP Coding Standards.
+
+There is also a semi-automated code quality analysis pushing results to [SonarCloud](https://sonarcloud.io/dashboard?id=de.stklcode.web.wordpress.plugins%3Astatify-blacklist).
+Keep in mind that the ruleset is not yet perfect, so not every minor issue has to be fixed immediately.
+
+## Still Open Questions?
+
+If anything is still left unanswered and you're unsure if you got it right, don't hesitate to contact a team member.
+in any case you might submit your request/issue anyway, we won't refuse good code only for formal reasons.

LICENSE.md

@@ -1,643 +1,317 @@
-                    GNU GENERAL PUBLIC LICENSE
-                       Version 3, 29 June 2007
+### GNU GENERAL PUBLIC LICENSE
 
- Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
- Everyone is permitted to copy and distribute verbatim copies
- of this license document, but changing it is not allowed.
+Version 2, June 1991
 
-                            Preamble
+    Copyright (C) 1989, 1991 Free Software Foundation, Inc.  
+    51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 
-  The GNU General Public License is a free, copyleft license for
-software and other kinds of works.
+    Everyone is permitted to copy and distribute verbatim copies
+    of this license document, but changing it is not allowed.
 
-  The licenses for most software and other practical works are designed
-to take away your freedom to share and change the works.  By contrast,
-the GNU General Public License is intended to guarantee your freedom to
-share and change all versions of a program--to make sure it remains free
-software for all its users.  We, the Free Software Foundation, use the
-GNU General Public License for most of our software; it applies also to
-any other work released this way by its authors.  You can apply it to
+### Preamble
+
+The licenses for most software are designed to take away your freedom
+to share and change it. By contrast, the GNU General Public License is
+intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users. This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it. (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.) You can apply it to
 your programs, too.
 
-  When we speak of free software, we are referring to freedom, not
-price.  Our General Public Licenses are designed to make sure that you
+When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
 have the freedom to distribute copies of free software (and charge for
-them if you wish), that you receive source code or can get it if you
-want it, that you can change the software or use pieces of it in new
-free programs, and that you know you can do these things.
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
 
-  To protect your rights, we need to prevent others from denying you
-these rights or asking you to surrender the rights.  Therefore, you have
-certain responsibilities if you distribute copies of the software, or if
-you modify it: responsibilities to respect the freedom of others.
+To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if
+you distribute copies of the software, or if you modify it.
 
-  For example, if you distribute copies of such a program, whether
-gratis or for a fee, you must pass on to the recipients the same
-freedoms that you received.  You must make sure that they, too, receive
-or can get the source code.  And you must show them these terms so they
-know their rights.
+For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
 
-  Developers that use the GNU GPL protect your rights with two steps:
-(1) assert copyright on the software, and (2) offer you this License
-giving you legal permission to copy, distribute and/or modify it.
+We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
 
-  For the developers' and authors' protection, the GPL clearly explains
-that there is no warranty for this free software.  For both users' and
-authors' sake, the GPL requires that modified versions be marked as
-changed, so that their problems will not be attributed erroneously to
-authors of previous versions.
+Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on,
+we want its recipients to know that what they have is not the
+original, so that any problems introduced by others will not reflect
+on the original authors' reputations.
 
-  Some devices are designed to deny users access to install or run
-modified versions of the software inside them, although the manufacturer
-can do so.  This is fundamentally incompatible with the aim of
-protecting users' freedom to change the software.  The systematic
-pattern of such abuse occurs in the area of products for individuals to
-use, which is precisely where it is most unacceptable.  Therefore, we
-have designed this version of the GPL to prohibit the practice for those
-products.  If such problems arise substantially in other domains, we
-stand ready to extend this provision to those domains in future versions
-of the GPL, as needed to protect the freedom of users.
+Finally, any free program is threatened constantly by software
+patents. We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at
+all.
 
-  Finally, every program is threatened constantly by software patents.
-States should not allow patents to restrict development and use of
-software on general-purpose computers, but in those that do, we wish to
-avoid the special danger that patents applied to a free program could
-make it effectively proprietary.  To prevent this, the GPL assures that
-patents cannot be used to render the program non-free.
-
-  The precise terms and conditions for copying, distribution and
+The precise terms and conditions for copying, distribution and
 modification follow.
 
-                       TERMS AND CONDITIONS
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-  When you convey a copy of a covered work, you may at your option
-remove any additional permissions from that copy, or from any part of
-it.  (Additional permissions may be written to require their own
-removal in certain cases when you modify the work.)  You may place
-additional permissions on material, added by you to a covered work,
-for which you have or can give appropriate copyright permission.
-
-  Notwithstanding any other provision of this License, for material you
-add to a covered work, you may (if authorized by the copyright holders of
-that material) supplement the terms of this License with terms:
-
-    a) Disclaiming warranty or limiting liability differently from the
-    terms of sections 15 and 16 of this License; or
-
-    b) Requiring preservation of specified reasonable legal notices or
-    author attributions in that material or in the Appropriate Legal
-    Notices displayed by works containing it; or
-
-    c) Prohibiting misrepresentation of the origin of that material, or
-    requiring that modified versions of such material be marked in
-    reasonable ways as different from the original version; or
-
-    d) Limiting the use for publicity purposes of names of licensors or
-    authors of the material; or
-
-    e) Declining to grant rights under trademark law for use of some
-    trade names, trademarks, or service marks; or
-
-    f) Requiring indemnification of licensors and authors of that
-    material by anyone who conveys the material (or modified versions of
-    it) with contractual assumptions of liability to the recipient, for
-    any liability that these contractual assumptions directly impose on
-    those licensors and authors.
-
-  All other non-permissive additional terms are considered "further
-restrictions" within the meaning of section 10.  If the Program as you
-received it, or any part of it, contains a notice stating that it is
-governed by this License along with a term that is a further
-restriction, you may remove that term.  If a license document contains
-a further restriction but permits relicensing or conveying under this
-License, you may add to a covered work material governed by the terms
-of that license document, provided that the further restriction does
-not survive such relicensing or conveying.
-
-  If you add terms to a covered work in accord with this section, you
-must place, in the relevant source files, a statement of the
-additional terms that apply to those files, or a notice indicating
-where to find the applicable terms.
-
-  Additional terms, permissive or non-permissive, may be stated in the
-form of a separately written license, or stated as exceptions;
-the above requirements apply either way.
-
-  8. Termination.
-
-  You may not propagate or modify a covered work except as expressly
-provided under this License.  Any attempt otherwise to propagate or
-modify it is void, and will automatically terminate your rights under
-this License (including any patent licenses granted under the third
-paragraph of section 11).
-
-  However, if you cease all violation of this License, then your
-license from a particular copyright holder is reinstated (a)
-provisionally, unless and until the copyright holder explicitly and
-finally terminates your license, and (b) permanently, if the copyright
-holder fails to notify you of the violation by some reasonable means
-prior to 60 days after the cessation.
-
-  Moreover, your license from a particular copyright holder is
-reinstated permanently if the copyright holder notifies you of the
-violation by some reasonable means, this is the first time you have
-received notice of violation of this License (for any work) from that
-copyright holder, and you cure the violation prior to 30 days after
-your receipt of the notice.
-
-  Termination of your rights under this section does not terminate the
-licenses of parties who have received copies or rights from you under
-this License.  If your rights have been terminated and not permanently
-reinstated, you do not qualify to receive new licenses for the same
-material under section 10.
-
-  9. Acceptance Not Required for Having Copies.
-
-  You are not required to accept this License in order to receive or
-run a copy of the Program.  Ancillary propagation of a covered work
-occurring solely as a consequence of using peer-to-peer transmission
-to receive a copy likewise does not require acceptance.  However,
-nothing other than this License grants you permission to propagate or
-modify any covered work.  These actions infringe copyright if you do
-not accept this License.  Therefore, by modifying or propagating a
-covered work, you indicate your acceptance of this License to do so.
-
-  10. Automatic Licensing of Downstream Recipients.
-
-  Each time you convey a covered work, the recipient automatically
-receives a license from the original licensors, to run, modify and
-propagate that work, subject to this License.  You are not responsible
-for enforcing compliance by third parties with this License.
-
-  An "entity transaction" is a transaction transferring control of an
-organization, or substantially all assets of one, or subdividing an
-organization, or merging organizations.  If propagation of a covered
-work results from an entity transaction, each party to that
-transaction who receives a copy of the work also receives whatever
-licenses to the work the party's predecessor in interest had or could
-give under the previous paragraph, plus a right to possession of the
-Corresponding Source of the work from the predecessor in interest, if
-the predecessor has it or can get it with reasonable efforts.
-
-  You may not impose any further restrictions on the exercise of the
-rights granted or affirmed under this License.  For example, you may
-not impose a license fee, royalty, or other charge for exercise of
-rights granted under this License, and you may not initiate litigation
-(including a cross-claim or counterclaim in a lawsuit) alleging that
-any patent claim is infringed by making, using, selling, offering for
-sale, or importing the Program or any portion of it.
-
-  11. Patents.
-
-  A "contributor" is a copyright holder who authorizes use under this
-License of the Program or a work on which the Program is based.  The
-work thus licensed is called the contributor's "contributor version".
-
-  A contributor's "essential patent claims" are all patent claims
-owned or controlled by the contributor, whether already acquired or
-hereafter acquired, that would be infringed by some manner, permitted
-by this License, of making, using, or selling its contributor version,
-but do not include claims that would be infringed only as a
-consequence of further modification of the contributor version.  For
-purposes of this definition, "control" includes the right to grant
-patent sublicenses in a manner consistent with the requirements of
+### TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+**0.** This License applies to any program or other work which
+contains a notice placed by the copyright holder saying it may be
+distributed under the terms of this General Public License. The
+"Program", below, refers to any such program or work, and a "work
+based on the Program" means either the Program or any derivative work
+under copyright law: that is to say, a work containing the Program or
+a portion of it, either verbatim or with modifications and/or
+translated into another language. (Hereinafter, translation is
+included without limitation in the term "modification".) Each licensee
+is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the Program
+(independent of having been made by running the Program). Whether that
+is true depends on what the Program does.
+
+**1.** You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a
+fee.
+
+**2.** You may modify your copy or copies of the Program or any
+portion of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+  
+**a)** You must cause the modified files to carry prominent notices
+stating that you changed the files and the date of any change.
+
+  
+**b)** You must cause any work that you distribute or publish, that in
+whole or in part contains or is derived from the Program or any part
+thereof, to be licensed as a whole at no charge to all third parties
+under the terms of this License.
+
+  
+**c)** If the modified program normally reads commands interactively
+when run, you must cause it, when started running for such interactive
+use in the most ordinary way, to print or display an announcement
+including an appropriate copyright notice and a notice that there is
+no warranty (or else, saying that you provide a warranty) and that
+users may redistribute the program under these conditions, and telling
+the user how to view a copy of this License. (Exception: if the
+Program itself is interactive but does not normally print such an
+announcement, your work based on the Program is not required to print
+an announcement.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote
+it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+**3.** You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+  
+**a)** Accompany it with the complete corresponding machine-readable
+source code, which must be distributed under the terms of Sections 1
+and 2 above on a medium customarily used for software interchange; or,
+
+  
+**b)** Accompany it with a written offer, valid for at least three
+years, to give any third party, for a charge no more than your cost of
+physically performing source distribution, a complete machine-readable
+copy of the corresponding source code, to be distributed under the
+terms of Sections 1 and 2 above on a medium customarily used for
+software interchange; or,
+
+  
+**c)** Accompany it with the information you received as to the offer
+to distribute corresponding source code. (This alternative is allowed
+only for noncommercial distribution and only if you received the
+program in object code or executable form with such an offer, in
+accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it. For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable. However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+**4.** You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License. Any attempt otherwise
+to copy, modify, sublicense or distribute the Program is void, and
+will automatically terminate your rights under this License. However,
+parties who have received copies, or rights, from you under this
+License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+**5.** You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+**6.** Each time you redistribute the Program (or any work based on
+the Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
 this License.
 
-  Each contributor grants you a non-exclusive, worldwide, royalty-free
-patent license under the contributor's essential patent claims, to
-make, use, sell, offer for sale, import and otherwise run, modify and
-propagate the contents of its contributor version.
+**7.** If, as a consequence of a court judgment or allegation of
+patent infringement or for any other reason (not limited to patent
+issues), conditions are imposed on you (whether by court order,
+agreement or otherwise) that contradict the conditions of this
+License, they do not excuse you from the conditions of this License.
+If you cannot distribute so as to satisfy simultaneously your
+obligations under this License and any other pertinent obligations,
+then as a consequence you may not distribute the Program at all. For
+example, if a patent license would not permit royalty-free
+redistribution of the Program by all those who receive copies directly
+or indirectly through you, then the only way you could satisfy both it
+and this License would be to refrain entirely from distribution of the
+Program.
 
-  In the following three paragraphs, a "patent license" is any express
-agreement or commitment, however denominated, not to enforce a patent
-(such as an express permission to practice a patent or covenant not to
-sue for patent infringement).  To "grant" such a patent license to a
-party means to make such an agreement or commitment not to enforce a
-patent against the party.
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
 
-  If you convey a covered work, knowingly relying on a patent license,
-and the Corresponding Source of the work is not available for anyone
-to copy, free of charge and under the terms of this License, through a
-publicly available network server or other readily accessible means,
-then you must either (1) cause the Corresponding Source to be so
-available, or (2) arrange to deprive yourself of the benefit of the
-patent license for this particular work, or (3) arrange, in a manner
-consistent with the requirements of this License, to extend the patent
-license to downstream recipients.  "Knowingly relying" means you have
-actual knowledge that, but for the patent license, your conveying the
-covered work in a country, or your recipient's use of the covered work
-in a country, would infringe one or more identifiable patents in that
-country that you have reason to believe are valid.
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
 
-  If, pursuant to or in connection with a single transaction or
-arrangement, you convey, or propagate by procuring conveyance of, a
-covered work, and grant a patent license to some of the parties
-receiving the covered work authorizing them to use, propagate, modify
-or convey a specific copy of the covered work, then the patent license
-you grant is automatically extended to all recipients of the covered
-work and works based on it.
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
 
-  A patent license is "discriminatory" if it does not include within
-the scope of its coverage, prohibits the exercise of, or is
-conditioned on the non-exercise of one or more of the rights that are
-specifically granted under this License.  You may not convey a covered
-work if you are a party to an arrangement with a third party that is
-in the business of distributing software, under which you make payment
-to the third party based on the extent of your activity of conveying
-the work, and under which the third party grants, to any of the
-parties who would receive the covered work from you, a discriminatory
-patent license (a) in connection with copies of the covered work
-conveyed by you (or copies made from those copies), or (b) primarily
-for and in connection with specific products or compilations that
-contain the covered work, unless you entered into that arrangement,
-or that patent license was granted, prior to 28 March 2007.
+**8.** If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded. In such case, this License incorporates
+the limitation as if written in the body of this License.
 
-  Nothing in this License shall be construed as excluding or limiting
-any implied license or other defenses to infringement that may
-otherwise be available to you under applicable patent law.
+**9.** The Free Software Foundation may publish revised and/or new
+versions of the General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
 
-  12. No Surrender of Others' Freedom.
+Each version is given a distinguishing version number. If the Program
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation. If the Program does not specify a
+version number of this License, you may choose any version ever
+published by the Free Software Foundation.
 
-  If conditions are imposed on you (whether by court order, agreement or
-otherwise) that contradict the conditions of this License, they do not
-excuse you from the conditions of this License.  If you cannot convey a
-covered work so as to satisfy simultaneously your obligations under this
-License and any other pertinent obligations, then as a consequence you may
-not convey it at all.  For example, if you agree to terms that obligate you
-to collect a royalty for further conveying from those to whom you convey
-the Program, the only way you could satisfy both those terms and this
-License would be to refrain entirely from conveying the Program.
+**10.** If you wish to incorporate parts of the Program into other
+free programs whose distribution conditions are different, write to
+the author to ask for permission. For software which is copyrighted by
+the Free Software Foundation, write to the Free Software Foundation;
+we sometimes make exceptions for this. Our decision will be guided by
+the two goals of preserving the free status of all derivatives of our
+free software and of promoting the sharing and reuse of software
+generally.
 
-  13. Use with the GNU Affero General Public License.
+**NO WARRANTY**
 
-  Notwithstanding any other provision of this License, you have
-permission to link or combine any covered work with a work licensed
-under version 3 of the GNU Affero General Public License into a single
-combined work, and to convey the resulting work.  The terms of this
-License will continue to apply to the part which is the covered work,
-but the special requirements of the GNU Affero General Public License,
-section 13, concerning interaction through a network will apply to the
-combination as such.
+**11.** BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
+PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
 
-  14. Revised Versions of this License.
+**12.** IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
+AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
+FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
+PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
 
-  The Free Software Foundation may publish revised and/or new versions of
-the GNU General Public License from time to time.  Such new versions will
-be similar in spirit to the present version, but may differ in detail to
-address new problems or concerns.
+### END OF TERMS AND CONDITIONS
 
-  Each version is given a distinguishing version number.  If the
-Program specifies that a certain numbered version of the GNU General
-Public License "or any later version" applies to it, you have the
-option of following the terms and conditions either of that numbered
-version or of any later version published by the Free Software
-Foundation.  If the Program does not specify a version number of the
-GNU General Public License, you may choose any version ever published
-by the Free Software Foundation.
+### How to Apply These Terms to Your New Programs
 
-  If the Program specifies that a proxy can decide which future
-versions of the GNU General Public License can be used, that proxy's
-public statement of acceptance of a version permanently authorizes you
-to choose that version for the Program.
-
-  Later license versions may give you additional or different
-permissions.  However, no additional obligations are imposed on any
-author or copyright holder as a result of your choosing to follow a
-later version.
-
-  15. Disclaimer of Warranty.
-
-  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
-APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
-HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
-OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
-THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
-IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
-ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
-
-  16. Limitation of Liability.
-
-  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
-THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
-GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
-USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
-DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
-PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
-EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGES.
-
-  17. Interpretation of Sections 15 and 16.
-
-  If the disclaimer of warranty and limitation of liability provided
-above cannot be given local legal effect according to their terms,
-reviewing courts shall apply local law that most closely approximates
-an absolute waiver of all civil liability in connection with the
-Program, unless a warranty or assumption of liability accompanies a
-copy of the Program in return for a fee.
-
-                     END OF TERMS AND CONDITIONS
-
-            How to Apply These Terms to Your New Programs
-
-  If you develop a new program, and you want it to be of the greatest
+If you develop a new program, and you want it to be of the greatest
 possible use to the public, the best way to achieve this is to make it
-free software which everyone can redistribute and change under these terms.
+free software which everyone can redistribute and change under these
+terms.
 
-  To do so, attach the following notices to the program.  It is safest
-to attach them to the start of each source file to most effectively
-state the exclusion of warranty; and each file should have at least
+To do so, attach the following notices to the program. It is safest to
+attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
 
-    {one line to give the program's name and a brief idea of what it does.}
-    Copyright (C) {year}  {name of author}
+    one line to give the program's name and an idea of what it does.
+    Copyright (C) yyyy  name of author
 
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation; either version 2
+    of the License, or (at your option) any later version.
 
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -645,31 +319,43 @@ the "copyright" line and a pointer to where the full notice is found.
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
-Also add information on how to contact you by electronic and paper mail.
+Also add information on how to contact you by electronic and paper
+mail.
 
-  If the program does terminal interaction, make it output a short
-notice like this when it starts in an interactive mode:
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
 
-    {project}  Copyright (C) {year}  {fullname}
-    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
-    This is free software, and you are welcome to redistribute it
-    under certain conditions; type `show c' for details.
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+    type `show w'.  This is free software, and you are welcome
+    to redistribute it under certain conditions; type `show c' 
+    for details.
 
-The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License.  Of course, your program's commands
-might be different; for a GUI interface, you would use an "about box".
+The hypothetical commands \`show w' and \`show c' should show the
+appropriate parts of the General Public License. Of course, the
+commands you use may be called something other than \`show w' and
+\`show c'; they could even be mouse-clicks or menu items--whatever
+suits your program.
 
-  You should also get your employer (if you work as a programmer) or school,
-if any, to sign a "copyright disclaimer" for the program, if necessary.
-For more information on this, and how to apply and follow the GNU GPL, see
-<http://www.gnu.org/licenses/>.
+You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the program,
+if necessary. Here is a sample; alter the names:
 
-  The GNU General Public License does not permit incorporating your program
-into proprietary programs.  If your program is a subroutine library, you
-may consider it more useful to permit linking proprietary applications with
-the library.  If this is what you want to do, use the GNU Lesser General
-Public License instead of this License.  But first, please read
-<http://www.gnu.org/philosophy/why-not-lgpl.html>.
+    Yoyodyne, Inc., hereby disclaims all copyright
+    interest in the program `Gnomovision'
+    (which makes passes at compilers) written 
+    by James Hacker.
 
+    signature of Ty Coon, 1 April 1989
+    Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library,
+you may consider it more useful to permit linking proprietary
+applications with the library. If this is what you want to do, use the
+[GNU Lesser General Public
+License](https://www.gnu.org/licenses/lgpl.html) instead of this
+License.

README.md

@@ -1,70 +1,156 @@
-# Statify Blacklist #
+[![Build Status](https://travis-ci.com/stklcode/statify-blacklist.svg?branch=master)](https://travis-ci.com/stklcode/statify-blacklist)
+[![Quality Gate](https://sonarcloud.io/api/project_badges/measure?project=de.stklcode.web.wordpress.plugins%3Astatify-blacklist&metric=alert_status)](https://sonarcloud.io/dashboard?id=de.stklcode.web.wordpress.plugins%3Astatify-blacklist)
+[![Packagist Version](https://img.shields.io/packagist/v/stklcode/statify-blacklist.svg)](https://packagist.org/packages/stklcode/statify-blacklist)
+[![License](https://img.shields.io/badge/license-GPL%20v2-blue.svg)](https://github.com/stklcode/statify-blacklist/blob/master/LICENSE.md)
+
+# Statify Filter #
 * Contributors:      Stefan Kalscheuer
-* Requires at least: 3.9
-* Tested up to:      4.6
-* Stable tag:        1.3.0
-* License:           GPLv3 or later
-* License URI:       https://www.gnu.org/licenses/gpl-3.0.html
+* Requires at least: 4.7
+* Tested up to:      5.6
+* Requires PHP:      5.5
+* Stable tag:        1.6.0
+* License:           GPLv2 or later
+* License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 
 ## Description ##
-A blacklist extension for the famous [Statify](http://statify.de) Wordpress plugin.
+A filter extension for the famous [Statify](https://wordpress.org/plugins/statify/) Wordpress plugin.
 
-This plugin adds customizable blacklist to Statify to allow blocking of referer spam or internal interactions.
+This plugin adds customizable filters to Statify to allow blocking of referer spam or internal interactions.
 
-### Current Features ##
-#### Referer Blacklist ####
+### Features ##
+
+#### Referer Filter ####
 Add a list of domains (for simplicity only second-level, e.g. _example.com_ which blocks _everything.example.com_).
 
+#### Target Filter ####
+Add a list of target pages (e.g. _/test/page/_, _/?page_id=123_) that will be excluded from tracking.
+
+#### IP Filter ####
+Add a list of IP addresses or subnets (e.g. _192.0.2.123_, _198.51.100.0/24_, _2001:db8:a0b:12f0::/64_).
+
+#### User Agent Filter ####
+Add a list of (partial) user agent strings to exclude (e.g. _curl_, _my/bot_, _Firefox_).
+
 #### CleanUp Database ####
 Filters can be applied to data stored in database after modifying filter rules or for one-time clean-up.
 
 #### Compatibility ####
-This plugin requires Statify to be installed. The extension has been tested with Statify 1.4.3
+This plugin requires Statify to be installed. The extension has been tested with Statify up to version 1.8
 The plugin is capable of handling multisite installations.
 
+### Support & Contributions ###
+* If you experience any issues, use the [support forums](https://wordpress.org/support/plugin/statify-blacklist).
+* Latest sources and development are handled on [GitHub](https://github.com/stklcode/statify-blacklist). You might contribute there or file an issue for code related bugs.
+* If you want to translate this plugin you can do this on [WordPress Translate](https://translate.wordpress.org/projects/wp-plugins/statify-blacklist).
+
 ### Credits ###
 * Author: Stefan Kalscheuer
-* Special Thanks to [pluginkollektiv](http://pluginkollektiv.org/) for maintaining _Statify_
+* Special Thanks to [pluginkollektiv](https://pluginkollektiv.org/) for maintaining _Statify_
 
 ## Installation ##
-* If you don’t know how to install a plugin for WordPress, [here’s how](http://codex.wordpress.org/Managing_Plugins#Installing_Plugins).
-* Make sure _Statify_ plugin is installed and active 
-* Goto _Settings_ -> _Statify Blacklist_ to configure the plugin
+* If you don’t know how to install a plugin for WordPress, [here’s how](https://wordpress.org/support/article/managing-plugins/#installing-plugins).
+* Make sure _Statify_ plugin is installed and active
+* Goto _Settings_ -> _Statify Filter_ to configure the plugin
 
 ### Requirements ###
-* PHP 5.2.4 or above
-* WordPress 3.9 or above
-* Statify plugin installed and activated (tested up to 1.4.3)
+* PHP 5.5 or above
+* WordPress 4.7 or above
+* _Statify_ plugin installed and activated (1.5 or above)
 
 ## Frequently Asked Questions ##
 
 ### What is blocked by default? ###
-Nothing. By default all blacklists are empty and disabled. They can and have to be filled by the blog administrator.
+Nothing. By default, all filters are empty and disabled. They can and have to be filled by the blog administrator.
 
-A default blacklist is not provided, as the plugin itself is totally neutral. If you want to filter out referer spam, 
-visitors from search engines or just "false" referers from 301 redirects only depends on you.
+A default filter is not provided, as the plugin itself is totally neutral. If you want to filter out referer spam, 
+visitors from search engines, just "false" referrers from 301 redirects or you own IP address used for testing only depends on you.
 
 ### Does the filter effect user experience? ###
-No. It only prevent's _Statify_ from tracking, nothing more or less.
+No. It only prevents _Statify_ from tracking, nothing more or less.
 
 ### Does live filtering impact performance? ###
-Yes, but probalby not noticeable. Checking a single referer string against a (usually small) list should be neglectible compared to the total loading procedure.
+Yes, but probably not noticeable. Checking a single referer string against a (usually small) list should be negligible compared to the total loading procedure.
 If this still is an issue for you, consider deactivating the filter and only run the one-time-cleanup or activate the cron job.
  
 ### Is any personal data collected? ###
 No. The privacy policy of _Statify_ is untouched. Data is only processed, not stored or exposed to anyone.
 
 ### Are regular expression filters possible? ###
-Yes, it it. Just select if you want to filter using regular expressions case sensitive or insensitive.
+Yes, it is. Just select regular expressions (case-sensitive or insensitive) as matching method instead of exact or keyword match.
 
-Note, that regular expression matching is significantly slower than the plain domain filter. Hence it is only recommended for asynchronous cron or manual execution and not for live filtering.
+### Why is IP and User Agent filtering only available as live filter? ###
+As you might know, _Statify_ does not store any personal information, including IP addresses in the database.
+Because of this, these filters can only be applied while processing the request and not afterwards.
+
+### Can whole IP subnet be blocked? ###
+Yes. The plugin features subnet filters using CIDR notation.
+For example _198.51.100.0/24_ filters all sources from _198.51.100.1_ to _198.51.100.254_.
+Same for IPv6 prefixes like _2001:db8:a0b:12f0::/64_.
 
 
 ## Screenshots ##
-1. Statify Blacklist settings page
+1. Statify Filter settings page
+
+## Upgrade Notice ##
+
+### 1.6.0 ###
+The plugin has been renamed from _Statify Blacklist_ to _Statify Filter_.
+This does not imply any changes in functionality, rather than using a better wording.
+
+In addition, there is a new filter by User Agent along with some minor corrections.
+This version should be compatible with latest WordPress 5.6.
+
 
 ## Changelog ##
 
+### 1.6.0 / 09.12.2020 ###
+
+Plugin renamed to _Statify Filter_.
+
+* Minor accessibility fixes on settings page
+* Introduced new user agent filter (#20)
+* Declared compatibility with WordPress 5.6
+
+### 1.5.2 / 03.09.2020 ###
+* Minor translation updates
+* Declared compatibility with WordPress 5.5
+
+### 1.5.1 / 20.05.2020 ###
+* Fix initialization on AJAX calls for _Statify_ 1.7 compatibility (#22)
+
+### 1.5.0 / 13.05.2020 ###
+* Minimum required WordPress version is 4.7
+* Removed `load_plugin_textdomain()` and `Domain Path` header
+* Added automatic compatibility check for WP and PHP version (#17)
+* Added keyword filter mode for referer blacklist (#15)
+* Layout adjustments on settings page
+* Regular expression filters are validated before saving (#13)
+
+### 1.4.4 / 19.05.2018 ###
+* Fix live filter chain when regular expressions are active (#12)
+
+### 1.4.3 / 09.01.2018 ###
+* Fix issues with multisite installation (#11)
+
+### 1.4.2 / 12.11.2017 ###
+* Minor code fixes
+
+### 1.4.1 / 16.07.2017 ###
+* Relicensed to GPLv2 or later
+* Fix filter hook if referer is disabled (#9)
+* Fix problem with faulty IPv6 netmask in IP blacklist
+* Minor changes for WP Coding Standard
+* Minimum required WordPress version is 4.4 (#10)
+
+### 1.4.0 / 10.06.2017 ###
+* IP blacklist implemented (#7)
+* Target page blacklist implemented (#8)
+* Internal configuration restructured (upgrade on plugin activation)
+* Statify hook name changed to `statify__skip_tracking` (as of Statify 1.5.0)
+
+### 1.3.1 / 09.12.2016 ###
+* Continue filtering if no filter applies (#6)
+
 ### 1.3.0 / 17.10.2016 ###
 * Regular expressions filtering implemented
 
@@ -73,7 +159,7 @@ Note, that regular expression matching is significantly slower than the plain do
 
 ### 1.2.0 / 29.08.2016 ###
 * Switched from `in_array()` to faster `isset()` for referer checking
-* Optional cron execiton implemented
+* Optional cron execution implemented
 
 ### 1.1.2 / 17.08.2016 ###
 * Prepared for localization

RoboFile.php

@@ -0,0 +1,396 @@
+<?php
+/**
+ * Statify Filter Robo build script.
+ *
+ * This file contains the Robo tasks for building a distributable plugin package.
+ * Should not be included in final package.
+ *
+ * @author    Stefan Kalscheuer <stefan@stklcode.de>
+ *
+ * @package   Statify_Blacklist
+ * @version   1.0.0
+ */
+
+use Robo\Exception\TaskException;
+use Robo\Tasks;
+
+/**
+ * Class RoboFile
+ */
+class RoboFile extends Tasks {
+	const PROJECT_NAME = 'statify-blacklist';
+	const SVN_URL      = 'https://plugins.svn.wordpress.org/statify-blacklist';
+
+	const OPT_TARGET    = 'target';
+	const OPT_SKIPTEST  = 'skipTests';
+	const OPT_SKIPSTYLE = 'skipStyle';
+
+	/**
+	 * Version tag (read from composer.json).
+	 *
+	 * @var string
+	 */
+	private $version;
+
+	/**
+	 * Target directory path.
+	 *
+	 * @var string
+	 */
+	private $target_dir;
+
+	/**
+	 * Final package name.
+	 *
+	 * @var string
+	 */
+	private $final_name;
+
+	/**
+	 * RoboFile constructor
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 */
+	public function __construct( $opts = [ self::OPT_TARGET => 'dist' ] ) {
+		// Read composer configuration and extract version number..
+		$composer = json_decode( file_get_contents( __DIR__ . '/composer.json' ) );
+		// Extract parameter from options.
+		$this->version    = $composer->version;
+		$this->target_dir = $opts[ self::OPT_TARGET ];
+		$this->final_name = self::PROJECT_NAME . '.' . $this->version;
+	}
+
+	/**
+	 * Clean up target directory
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 */
+	public function clean( $opts = [ self::OPT_TARGET => 'dist' ] ) {
+		$this->say( 'Cleaning target directory...' );
+		if ( is_dir( $this->target_dir . '/' . $this->final_name ) ) {
+			$this->_deleteDir( [ $this->target_dir . '/' . $this->final_name ] );
+		}
+		if ( is_file( $this->target_dir . '/' . $this->final_name . '.zip' ) ) {
+			$this->_remove( $this->target_dir . '/' . $this->final_name . '.zip' );
+		}
+	}
+
+	/**
+	 * Run PHPUnit tests
+	 *
+	 * @return void
+	 */
+	public function test() {
+		$this->say( 'Executing PHPUnit tests...' );
+		$this->taskPhpUnit()->configFile( __DIR__ . '/phpunit.xml' )->run();
+	}
+
+	/**
+	 * Run code style tests
+	 *
+	 * @return void
+	 */
+	public function testCS() {
+		$this->say( 'Executing PHPCS tests...' );
+		$this->_exec( __DIR__ . '/vendor/bin/phpcs --standard=phpcs.xml -s' );
+	}
+
+	/**
+	 * Build a distributable bundle.
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 */
+	public function build(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		$this->clean( $opts );
+		if ( isset( $opts[ self::OPT_SKIPTEST ] ) && true === $opts[ self::OPT_SKIPTEST ] ) {
+			$this->say( 'Tests skipped' );
+		} else {
+			$this->test();
+		}
+		if ( isset( $opts[ self::OPT_SKIPSTYLE ] ) && true === $opts[ self::OPT_SKIPSTYLE ] ) {
+			$this->say( 'Style checks skipped' );
+		} else {
+			$this->testCS();
+		}
+		$this->bundle();
+	}
+
+	/**
+	 * Bundle global resources.
+	 *
+	 * @return void
+	 */
+	private function bundle() {
+		$this->say( 'Bundling resources...' );
+		$this->taskCopyDir(
+			[
+				'inc'   => $this->target_dir . '/' . $this->final_name . '/inc',
+				'views' => $this->target_dir . '/' . $this->final_name . '/views',
+			]
+		)->run();
+		$this->_copy( 'statify-blacklist.php', $this->target_dir . '/' . $this->final_name . '/statify-blacklist.php' );
+		$this->_copy( 'LICENSE.md', $this->target_dir . '/' . $this->final_name . '/LICENSE.md' );
+		$this->_copy( 'README.md', $this->target_dir . '/' . $this->final_name . '/README.md' );
+
+		// Remove content before title (e.g. badges) from README file.
+		$this->taskReplaceInFile( $this->target_dir . '/' . $this->final_name . '/README.md' )
+			->regex( '/^[^\\#]*/' )
+			->to( '' )
+			->run();
+	}
+
+	/**
+	 * Create ZIP package from distribution bundle.
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 */
+	public function package(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		$this->build( $opts );
+		$this->say( 'Packaging...' );
+		$this->taskPack( $this->target_dir . '/' . $this->final_name . '.zip' )
+			->addDir( '', $this->target_dir . '/' . $this->final_name )
+			->run();
+	}
+
+	/**
+	 * Deploy development version (trunk).
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	public function deployTrunk(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		// First execute build job.
+		$this->build( $opts );
+
+		// Prepare VCS, either checkout or update local copy.
+		$this->prepareVCS();
+
+		$this->say( 'Preparing deployment directory...' );
+		$this->updateVCStrunk();
+
+		// Update remote repository.
+		$this->say( 'Deploying...' );
+		$this->commitVCS(
+			'--force trunk/*',
+			'Updated ' . self::PROJECT_NAME . ' trunk'
+		);
+	}
+
+	/**
+	 * Deploy current version tag.
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	public function deployTag(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		// First execute build job.
+		$this->build( $opts );
+
+		// Prepare VCS, either checkout or update local copy.
+		$this->prepareVCS();
+
+		$this->say( 'Preparing deployment directory...' );
+		$this->updateVCStag();
+
+		// Update remote repository.
+		$this->say( 'Deploying...' );
+		$this->commitVCS(
+			'tags/' . $this->version,
+			'Updated ' . self::PROJECT_NAME . ' v' . $this->version
+		);
+	}
+
+	/**
+	 * Deploy current version tag.
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	public function deployReadme(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		// First execute build job.
+		$this->build( $opts );
+
+		// Prepare VCS, either checkout or update local copy.
+		$this->prepareVCS();
+
+		$this->updateVCSreadme();
+
+		// Update remote repository.
+		$this->say( 'Deploying...' );
+		$this->commitVCS(
+			'--force trunk/README.md',
+			'Updated ' . self::PROJECT_NAME . ' ReadMe'
+		);
+	}
+
+	/**
+	 * Deploy current version tag and trunk.
+	 *
+	 * @param array $opts Options.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	public function deployAll(
+		$opts = [
+			self::OPT_TARGET    => 'dist',
+			self::OPT_SKIPTEST  => false,
+			self::OPT_SKIPSTYLE => false,
+		]
+	) {
+		// First execute build job.
+		$this->build( $opts );
+
+		// Prepare VCS, either checkout or update local copy.
+		$this->prepareVCS();
+
+		$this->say( 'Preparing deployment directory...' );
+		$this->updateVCStrunk();
+		$this->updateVCStag();
+
+		// Update remote repository.
+		$this->say( 'Deploying...' );
+		$this->commitVCS(
+			[
+				'--force trunk/*',
+				'--force tags/' . $this->version,
+			],
+			'Updated ' . self::PROJECT_NAME . ' v' . $this->version
+		);
+	}
+
+	/**
+	 * Prepare VCS direcory.
+	 *
+	 * Checkout or update local copy of SVN repository.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	private function prepareVCS() {
+		if ( is_dir( $this->target_dir . '/svn' ) ) {
+			$this->taskSvnStack()
+				->stopOnFail()
+				->dir( $this->target_dir . '/svn/statify-blacklist' )
+				->update()
+				->run();
+		} else {
+			$this->_mkdir( $this->target_dir . '/svn' );
+			$this->taskSvnStack()
+				->dir( $this->target_dir . '/svn' )
+				->checkout( self::SVN_URL )
+				->run();
+		}
+	}
+
+	/**
+	 * Commit VCS changes
+	 *
+	 * @param string|array $to_add Files to add.
+	 * @param string       $msg    Commit message.
+	 *
+	 * @return void
+	 * @throws TaskException On errors.
+	 */
+	private function commitVCS( $to_add, $msg ) {
+		$task = $this->taskSvnStack()
+					->stopOnFail()
+					->dir( $this->target_dir . '/svn/statify-blacklist' );
+
+		if ( is_array( $to_add ) ) {
+			foreach ( $to_add as $ta ) {
+				$task = $task->add( $ta );
+			}
+		} else {
+			$task = $task->add( $to_add );
+		}
+
+		$task->commit( $msg )->run();
+	}
+
+	/**
+	 * Update SVN readme file.
+	 *
+	 * @return void
+	 */
+	private function updateVCSreadme() {
+		$trunk_dir = $this->target_dir . '/svn/statify-blacklist/trunk';
+		$this->_copy( $this->target_dir . '/' . $this->final_name . '/README.md', $trunk_dir . '/README.md' );
+	}
+
+	/**
+	 * Update SVN development version (trunk).
+	 *
+	 * @return void
+	 */
+	private function updateVCStrunk() {
+		// Clean trunk directory.
+		$trunk_dir = $this->target_dir . '/svn/statify-blacklist/trunk';
+		$this->taskCleanDir( $trunk_dir )->run();
+
+		// Copy built bundle to trunk.
+		$this->taskCopyDir( [ $this->target_dir . '/' . $this->final_name => $trunk_dir ] )->run();
+	}
+
+	/**
+	 * Update current SVN version tag.
+	 *
+	 * @return void
+	 */
+	private function updateVCStag() {
+		// Clean tag directory if it exists.
+		$tag_dir = $this->target_dir . '/svn/statify-blacklist/tags/' . $this->version;
+		if ( is_dir( $tag_dir ) ) {
+			$this->taskCleanDir( $this->target_dir . '/svn/statify-blacklist/tags/' . $this->version )->run();
+		} else {
+			$this->_mkdir( $tag_dir );
+		}
+
+		// Copy built bundle to trunk.
+		$this->taskCopyDir( [ $this->target_dir . '/' . $this->final_name => $tag_dir ] )->run();
+	}
+}

composer.json

@@ -0,0 +1,58 @@
+{
+  "name": "stklcode/statify-blacklist",
+  "version": "1.6.0",
+  "description": "A filter extension for the famous Statify WordPress plugin",
+  "keywords": [
+    "wordpress",
+    "plugin",
+    "statistics",
+    "filter"
+  ],
+  "license": "GPL-2.0-or-later",
+  "authors": [
+    {
+      "name": "Stefan Kalscheuer",
+      "email": "stefan@stklcode.de",
+      "homepage": "https://www.stklcode.de"
+    }
+  ],
+  "type": "wordpress-plugin",
+  "require": {
+    "php": ">=5.5",
+    "composer/installers": "~1.9"
+  },
+  "require-dev": {
+    "dealerdirect/phpcodesniffer-composer-installer": "^0.7",
+    "consolidation/robo": "^1.4",
+    "phpunit/phpunit": "*",
+    "phpunit/php-code-coverage": "*",
+    "slowprog/composer-copy-file": "~0.3",
+    "squizlabs/php_codesniffer": "^3.5",
+    "phpcompatibility/phpcompatibility-wp": "^2.1",
+    "wp-coding-standards/wpcs": "^2.3"
+  },
+  "scripts": {
+    "build": [
+      "robo build"
+    ],
+    "package": [
+      "robo package"
+    ],
+    "deploy": [
+      "robo deploy:all"
+    ],
+    "test-all": [
+      "@test",
+      "@test-cs"
+    ],
+    "test": [
+      "phpunit"
+    ],
+    "test-cs": [
+      "phpcs --standard=phpcs.xml -s"
+    ],
+    "fix-cs": [
+      "phpcbf --standard=phpcs.xml"
+    ]
+  }
+}

inc/class-statifyblacklist-admin.php

@@ -0,0 +1,366 @@
+<?php
+/**
+ * Statify Filter: StatifyBlacklist_Admin class
+ *
+ * This file contains the derived class for the plugin's administration features.
+ *
+ * @package   Statify_Blacklist
+ * @subpackge Admin
+ * @since     1.0.0
+ */
+
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+/**
+ * Statify Filter admin configuration.
+ *
+ * @since   1.0.0
+ */
+class StatifyBlacklist_Admin extends StatifyBlacklist {
+
+	/**
+	 * Initialize admin-only components of the plugin.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @return void
+	 */
+	public static function init() {
+		// Add actions.
+		add_action( 'wpmu_new_blog', array( 'StatifyBlacklist_System', 'install_site' ) );
+		add_action( 'delete_blog', array( 'StatifyBlacklist_System', 'uninstall_site' ) );
+		add_filter( 'plugin_row_meta', array( 'StatifyBlacklist_Admin', 'plugin_meta_link' ), 10, 2 );
+
+		if ( self::$multisite ) {
+			add_action( 'network_admin_menu', array( 'StatifyBlacklist_Admin', 'add_menu_page' ) );
+			add_filter(
+				'network_admin_plugin_action_links',
+				array(
+					'StatifyBlacklist_Admin',
+					'plugin_actions_links',
+				),
+				10,
+				2
+			);
+		} else {
+			add_action( 'admin_menu', array( 'StatifyBlacklist_Admin', 'add_menu_page' ) );
+			add_filter( 'plugin_action_links', array( 'StatifyBlacklist_Admin', 'plugin_actions_links' ), 10, 2 );
+		}
+	}
+
+	/**
+	 * Update options.
+	 *
+	 * @since 1.1.1
+	 *
+	 * @param  array $options Optional. New options to save.
+	 *
+	 * @return array|bool  array of sanitized array on errors, FALSE if there were none.
+	 */
+	public static function update_options( $options = null ) {
+		if ( isset( $options ) && current_user_can( 'manage_options' ) ) {
+
+			// Sanitize referer list.
+			$given_referer   = $options['referer']['blacklist'];
+			$invalid_referer = array();
+			if ( self::MODE_NORMAL === $options['referer']['regexp'] ) {
+				// Sanitize URLs and remove empty inputs.
+				$sanitized_referer = self::sanitize_urls( $given_referer );
+			} elseif ( self::MODE_REGEX === $options['referer']['regexp'] || self::MODE_REGEX_CI === $options['referer']['regexp'] ) {
+				$sanitized_referer = $given_referer;
+				// Check regular expressions.
+				$invalid_referer = self::sanitize_regex( $given_referer );
+			} else {
+				$sanitized_referer = $given_referer;
+			}
+
+			// Sanitize target list.
+			$given_target   = $options['target']['blacklist'];
+			$invalid_target = array();
+			if ( self::MODE_REGEX === $options['target']['regexp'] || self::MODE_REGEX_CI === $options['target']['regexp'] ) {
+				$sanitized_target = $given_target;
+				// Check regular expressions.
+				$invalid_target = self::sanitize_regex( $given_target );
+			} else {
+				$sanitized_target = $given_target;
+			}
+
+			// Sanitize IPs and subnets and remove empty inputs.
+			$given_ip     = $options['ip']['blacklist'];
+			$sanitized_ip = self::sanitize_ips( $given_ip );
+
+			// Abort on errors.
+			$errors = array(
+				'referer' => array(
+					'sanitized' => $sanitized_referer,
+					'diff'      => array_diff( $given_referer, $sanitized_referer ),
+					'invalid'   => $invalid_referer,
+				),
+				'target'  => array(
+					'sanitized' => $sanitized_target,
+					'diff'      => array_diff( $given_target, $sanitized_target ),
+					'invalid'   => $invalid_target,
+				),
+				'ip'      => array(
+					'sanitized' => $sanitized_ip,
+					'diff'      => array_diff( $given_ip, $sanitized_ip ),
+				),
+			);
+			if ( ! empty( $errors['referer']['diff'] )
+				|| ! empty( $errors['referer']['invalid'] )
+				|| ! empty( $errors['target']['diff'] )
+				|| ! empty( $errors['target']['invalid'] )
+				|| ! empty( $errors['ip']['diff'] ) ) {
+				return $errors;
+			}
+
+			// Update database on success.
+			if ( self::$multisite ) {
+				update_site_option( 'statify-blacklist', $options );
+			} else {
+				update_option( 'statify-blacklist', $options );
+			}
+		}
+
+		// Refresh options.
+		parent::update_options( $options );
+
+		return false;
+	}
+
+	/**
+	 * Add configuration page to admin menu.
+	 *
+	 * @since 1.0.0
+	 */
+	public static function add_menu_page() {
+		$title = __( 'Statify Filter', 'statify-blacklist' );
+		if ( self::$multisite ) {
+			add_submenu_page(
+				'settings.php',
+				$title,
+				$title,
+				'manage_network_plugins',
+				'statify-blacklist-settings',
+				array(
+					'StatifyBlacklist_Admin',
+					'settings_page',
+				)
+			);
+		} else {
+			add_submenu_page(
+				'options-general.php',
+				$title,
+				$title,
+				'manage_options',
+				'statify-blacklist',
+				array(
+					'StatifyBlacklist_Admin',
+					'settings_page',
+				)
+			);
+		}
+
+	}
+
+	/**
+	 * Include the Statify-Blacklist settings page.
+	 *
+	 * @since 1.0.0
+	 */
+	public static function settings_page() {
+		include STATIFYBLACKLIST_DIR . '/views/settings-page.php';
+	}
+
+	/**
+	 * Add plugin meta links
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param array  $links Registered links.
+	 * @param string $file  The filename.
+	 *
+	 * @return array  Merged links.
+	 */
+	public static function plugin_meta_link( $links, $file ) {
+		if ( STATIFYBLACKLIST_BASE === $file ) {
+			$links[] = '<a href="https://github.com/stklcode/statify-blacklist">GitHub</a>';
+		}
+
+		return $links;
+	}
+
+	/**
+	 * Add plugin action links.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param array  $links Registered links.
+	 * @param string $file  The filename.
+	 *
+	 * @return array  Merged links.
+	 */
+	public static function plugin_actions_links( $links, $file ) {
+		$base = self::$multisite ? network_admin_url( 'settings.php' ) : admin_url( 'options-general.php' );
+
+		if ( STATIFYBLACKLIST_BASE === $file && current_user_can( 'manage_options' ) ) {
+			array_unshift(
+				$links,
+				sprintf( '<a href="%s">%s</a>', esc_attr( add_query_arg( 'page', 'statify-blacklist', $base ) ), __( 'Settings', 'statify-blacklist' ) )
+			);
+		}
+
+		return $links;
+	}
+
+	/**
+	 * Filter database for cleanup.
+	 *
+	 * @since 1.1.0
+	 *
+	 * @global wpdb $wpdb WordPress database.
+	 */
+	public static function cleanup_database() {
+		// Check user permissions.
+		if ( ! current_user_can( 'manage_options' ) && ! ( defined( 'DOING_CRON' ) && DOING_CRON ) ) {
+			die( esc_html__( 'Are you sure you want to do this?', 'statify-blacklist' ) );
+		}
+
+		if ( defined( 'DOING_CRON' ) && DOING_CRON ) {
+			$clean_ref = ( 1 === self::$options['referer']['cron'] );
+			$clean_trg = ( 1 === self::$options['target']['cron'] );
+		} else {
+			$clean_ref = true;
+			$clean_trg = true;
+		}
+
+		if ( $clean_ref ) {
+			if ( isset( self::$options['referer']['regexp'] ) && self::$options['referer']['regexp'] > 0 ) {
+				// Merge given regular expressions into one.
+				$referer_regexp = implode( '|', array_keys( self::$options['referer']['blacklist'] ) );
+			} else {
+				// Sanitize URLs.
+				$referer = self::sanitize_urls( self::$options['referer']['blacklist'] );
+
+				// Build filter regexp.
+				$referer_regexp = str_replace( '.', '\.', implode( '|', array_flip( $referer ) ) );
+			}
+		}
+
+		if ( $clean_trg ) {
+			if ( isset( self::$options['target']['regexp'] ) && self::$options['target']['regexp'] > 0 ) {
+				// Merge given regular expressions into one.
+				$target_regexp = implode( '|', array_keys( self::$options['target']['blacklist'] ) );
+			} else {
+				// Build filter regexp.
+				$target_regexp = str_replace( '.', '\.', implode( '|', array_flip( self::$options['target']['blacklist'] ) ) );
+			}
+		}
+
+		if ( ! empty( $referer_regexp ) || ! empty( $target_regexp ) ) {
+			global $wpdb;
+
+			// Execute filter on database.
+			// phpcs:disable WordPress.DB.PreparedSQL.NotPrepared -- These statements produce warnings, rework in future release (TODO).
+			if ( ! empty( $referer_regexp ) ) {
+				$wpdb->query(
+					$wpdb->prepare(
+						"DELETE FROM `$wpdb->statify` WHERE "
+						. ( ( 1 === self::$options['referer']['regexp'] ) ? ' BINARY ' : '' )
+						. 'referrer REGEXP %s',
+						$referer_regexp
+					)
+				);
+			}
+			if ( ! empty( $target_regexp ) ) {
+				$wpdb->query(
+					$wpdb->prepare(
+						"DELETE FROM `$wpdb->statify` WHERE "
+						. ( ( 1 === self::$options['target']['regexp'] ) ? ' BINARY ' : '' )
+						. 'target REGEXP %s',
+						$target_regexp
+					)
+				);
+			}
+			// phpcs:enable WordPress.DB.PreparedSQL.NotPrepared
+
+			// Optimize DB.
+			$wpdb->query( "OPTIMIZE TABLE `$wpdb->statify`" );
+
+			// Delete transient statify data.
+			delete_transient( 'statify_data' );
+		}
+	}
+
+
+	/**
+	 * Sanitize URLs and remove empty results.
+	 *
+	 * @since 1.1.1
+	 *
+	 * @param array $urls given array of URLs.
+	 *
+	 * @return array  sanitized array.
+	 */
+	private static function sanitize_urls( $urls ) {
+		return array_flip(
+			array_filter(
+				array_map(
+					function ( $r ) {
+						return preg_replace( '/[^\da-z\.-]/i', '', filter_var( $r, FILTER_SANITIZE_URL ) );
+					},
+					array_flip( $urls )
+				)
+			)
+		);
+	}
+
+	/**
+	 * Sanitize IP addresses with optional CIDR notation and remove empty results.
+	 *
+	 * @since 1.4.0
+	 *
+	 * @param array $ips given array of URLs.
+	 *
+	 * @return array  sanitized array.
+	 */
+	private static function sanitize_ips( $ips ) {
+		return array_filter(
+			$ips,
+			function ( $ip ) {
+				return preg_match(
+					'/^((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])(\/([0-9]|[1-2][0-9]|3[0-2]))?$/',
+					$ip
+				) ||
+				preg_match(
+					'/^(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))(\/([0-9]|[1-9][0-9]|1[0-1][0-9]|12[0-8]))?$/',
+					$ip
+				);
+			}
+		);
+	}
+
+	/**
+	 * Validate regular expressions, i.e. remove duplicates and empty values and validate others.
+	 *
+	 * @since 1.5.0 #13
+	 *
+	 * @param array $expressions Given pre-sanitized array of regular expressions.
+	 *
+	 * @return array Array of invalid expressions.
+	 */
+	private static function sanitize_regex( $expressions ) {
+		return array_filter(
+			array_flip( $expressions ),
+			function ( $re ) {
+				// Check of preg_match() fails (warnings suppressed).
+
+				// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
+				return false === @preg_match( StatifyBlacklist::regex( $re, false ), null );
+			}
+		);
+	}
+}

inc/class-statifyblacklist-system.php

@@ -0,0 +1,193 @@
+<?php
+/**
+ * Statify Filter: StatifyBlacklist_System class
+ *
+ * This file contains the derived class for the plugin's system operations.
+ *
+ * @package   Statify_Blacklist
+ * @subpackge System
+ * @since     1.0.0
+ */
+
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+/**
+ * Statify Filter system configuration.
+ *
+ * @since   1.0.0
+ */
+class StatifyBlacklist_System extends StatifyBlacklist {
+
+	/**
+	 * Plugin install handler.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param bool $network_wide Whether the plugin was activated network-wide or not.
+	 *
+	 * @return void
+	 */
+	public static function install( $network_wide = false ) {
+		// Create tables for each site in a network.
+		if ( $network_wide && is_multisite() ) {
+			if ( function_exists( 'get_sites' ) ) {
+				$sites = get_sites();
+			} else {
+				return;
+			}
+
+			foreach ( $sites as $site ) {
+				if ( is_array( $site ) ) {
+					$site_id = $site['blog_id'];
+				} else {
+					$site_id = $site->blog_id;
+				}
+				self::install_site( $site_id );
+			}
+
+			restore_current_blog();
+		} else {
+			add_option(
+				'statify-blacklist',
+				self::default_options()
+			);
+		}
+	}
+
+	/**
+	 * Set up the plugin for a single site on Multisite.
+	 *
+	 * @since 1.4.3
+	 *
+	 * @param integer $site_id Site ID.
+	 *
+	 * @return void
+	 */
+	public static function install_site( $site_id ) {
+		switch_to_blog( (int) $site_id );
+		add_option(
+			'statify-blacklist',
+			self::default_options()
+		);
+		restore_current_blog();
+	}
+
+
+	/**
+	 * Plugin uninstall handler.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @return void
+	 */
+	public static function uninstall() {
+		if ( is_multisite() ) {
+			$old = get_current_blog_id();
+
+			if ( function_exists( 'get_sites' ) ) {
+				$sites = get_sites();
+			} elseif ( function_exists( 'wp_get_sites' ) ) {
+				// phpcs:ignore WordPress.WP.DeprecatedFunctions.wp_get_sitesFound -- Legacy support for WP < 4.6.
+				$sites = wp_get_sites();
+			} else {
+				return;
+			}
+
+			foreach ( $sites as $site ) {
+				if ( is_array( $site ) ) {
+					$site_id = $site['blog_id'];
+				} else {
+					$site_id = $site->blog_id;
+				}
+				self::uninstall_site( $site_id );
+			}
+
+			switch_to_blog( $old );
+		}
+
+		delete_option( 'statify-blacklist' );
+	}
+
+	/**
+	 * Remove the plugin for a single site on Multisite.
+	 *
+	 * @since 1.4.3
+	 *
+	 * @param integer $site_id Site ID.
+	 *
+	 * @return void
+	 */
+	public static function uninstall_site( $site_id ) {
+		$old = get_current_blog_id();
+		switch_to_blog( (int) $site_id );
+		delete_option( 'statify-blacklist' );
+		switch_to_blog( $old );
+	}
+
+	/**
+	 * Upgrade plugin options.
+	 *
+	 * @since 1.2.0
+	 *
+	 * @return void
+	 */
+	public static function upgrade() {
+		self::update_options();
+		// Check if config array is not associative (pre 1.2.0).
+		if ( array_keys( self::$options['referer'] ) === range( 0, count( self::$options['referer'] ) - 1 ) ) {
+			// Flip referer array to make domains keys.
+			$options            = self::$options;
+			$options['referer'] = array_flip( self::$options['referer'] );
+			if ( self::$multisite ) {
+				update_site_option( 'statify-blacklist', $options );
+			} else {
+				update_option( 'statify-blacklist', $options );
+			}
+		}
+
+		// Version not set (pre 1.3.0) or older than 1.4.
+		if ( ! isset( self::$options['version'] ) || self::$options['version'] < 1.4 ) {
+			// Upgrade options to new schema.
+			$options = array(
+				'referer' => array(
+					'active'    => self::$options['active_referer'],
+					'cron'      => self::$options['cron_referer'],
+					'regexp'    => self::$options['referer_regexp'],
+					'blacklist' => self::$options['referer'],
+				),
+				'target'  => array(
+					'active'    => 0,
+					'cron'      => 0,
+					'regexp'    => 0,
+					'blacklist' => array(),
+				),
+				'ip'      => array(
+					'active'    => 0,
+					'blacklist' => array(),
+				),
+				'version' => 1.4,
+			);
+			if ( self::$multisite ) {
+				update_site_option( 'statify-blacklist', $options );
+			} else {
+				update_option( 'statify-blacklist', $options );
+			}
+			self::update_options();
+		}
+
+		// Version older than current major release.
+		if ( self::VERSION_MAIN > self::$options['version'] ) {
+			// Merge default options with current config, assuming only additive changes.
+			$options            = array_merge_recursive( self::default_options(), self::$options );
+			$options['version'] = self::VERSION_MAIN;
+			if ( self::$multisite ) {
+				update_site_option( 'statify-blacklist', $options );
+			} else {
+				update_option( 'statify-blacklist', $options );
+			}
+		}
+	}
+}

inc/class-statifyblacklist.php

@@ -0,0 +1,472 @@
+<?php
+/**
+ * Statify Filter: StatifyBlacklist class
+ *
+ * This file contains the plugin's base class.
+ *
+ * @package Statify_Blacklist
+ * @since   1.0.0
+ */
+
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+/**
+ * Statify Filter.
+ */
+class StatifyBlacklist {
+
+	/**
+	 * Plugin major version.
+	 *
+	 * @since 1.4.0
+	 * @var int VERSION_MAIN
+	 */
+	const VERSION_MAIN = 1.4;
+
+	/**
+	 * Operation mode "normal".
+	 *
+	 * @var integer MODE_NORMAL
+	 */
+	const MODE_NORMAL = 0;
+
+	/**
+	 * Operation mode "regular expression".
+	 *
+	 * @var integer MODE_REGEX
+	 */
+	const MODE_REGEX = 1;
+
+	/**
+	 * Operation mode "regular expression case insensitive".
+	 *
+	 * @var integer MODE_REGEX_CI
+	 */
+	const MODE_REGEX_CI = 2;
+
+	/**
+	 * Operation mode "keyword".
+	 *
+	 * @since 1.5.0
+	 * @var integer MODE_KEYWORD
+	 */
+	const MODE_KEYWORD = 3;
+
+	/**
+	 * Plugin options.
+	 *
+	 * @since 1.0.0
+	 * @var array $options
+	 */
+	public static $options;
+
+	/**
+	 * Multisite Status.
+	 *
+	 * @since 1.0.0
+	 * @var bool $multisite
+	 */
+	public static $multisite;
+
+	/**
+	 * Plugin initialization.
+	 *
+	 * @since 1.4.2
+	 *
+	 * @return void
+	 */
+	public static function init() {
+		// Skip on autosave.
+		if ( ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) ) {
+			return;
+		}
+
+		// Get multisite status.
+		self::$multisite = ( is_multisite() && array_key_exists( STATIFYBLACKLIST_BASE, (array) get_site_option( 'active_sitewide_plugins' ) ) );
+
+		// Plugin options.
+		self::update_options();
+
+		// Add Filter to statify hook if enabled.
+		if ( 0 !== self::$options['referer']['active'] ||
+			0 !== self::$options['target']['active'] ||
+			0 !== self::$options['ip']['active'] ||
+			0 !== self::$options['ua']['active'] ) {
+			add_filter( 'statify__skip_tracking', array( 'StatifyBlacklist', 'apply_blacklist_filter' ) );
+		}
+
+		// Statify uses WP AJAX as of 1.7, so we need to reach this point. But there are no further admin/cron actions.
+		if ( defined( 'DOING_AJAX' ) && DOING_AJAX ) {
+			return;
+		}
+
+		// Admin only filters.
+		if ( is_admin() ) {
+			StatifyBlacklist_Admin::init();
+		}
+
+		// CronJob to clean up database.
+		if ( defined( 'DOING_CRON' ) && DOING_CRON &&
+			( 1 === self::$options['referer']['cron'] || 1 === self::$options['target']['cron'] ) ) {
+			add_action( 'statify_cleanup', array( 'StatifyBlacklist_Admin', 'cleanup_database' ) );
+		}
+	}
+
+	/**
+	 * Update options.
+	 *
+	 * @since 1.0.0
+	 * @since 1.2.1 update_options($options = null) Parameter with default value introduced.
+	 *
+	 * @param array $options Optional. New options to save.
+	 *
+	 * @return void
+	 */
+	public static function update_options( $options = null ) {
+		if ( self::$multisite ) {
+			$o = get_site_option( 'statify-blacklist' );
+		} else {
+			$o = get_option( 'statify-blacklist' );
+		}
+		self::$options = wp_parse_args( $o, self::default_options() );
+	}
+
+	/**
+	 * Create default plugin configuration.
+	 *
+	 * @since 1.4.0
+	 *
+	 * @return array The options array.
+	 */
+	protected static function default_options() {
+		return array(
+			'referer' => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => 0,
+				'blacklist' => array(),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => 0,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => 0,
+				'blacklist' => array(),
+			),
+			'version' => self::VERSION_MAIN,
+		);
+	}
+
+	/**
+	 * Apply the filter if active
+	 *
+	 * @since 1.0.0
+	 *
+	 * @return bool TRUE if referer matches filter.
+	 */
+	public static function apply_blacklist_filter() {
+		// Referer filter.
+		if (
+		self::apply_single_filter(
+			self::$options['referer'],
+			array(
+				__CLASS__,
+				( ! isset( self::$options['referer']['regexp'] ) || self::MODE_NORMAL === self::$options['referer']['regexp'] ) ? 'get_referer_domain' : 'get_referer',
+			)
+		)
+		) {
+			return true;
+		}
+
+		// Target filter (since 1.4.0).
+		if ( self::apply_single_filter( self::$options['target'], array( __CLASS__, 'get_target' ) ) ) {
+			return true;
+		}
+
+		// IP filter (since 1.4.0).
+		if ( isset( self::$options['ip']['active'] ) && 0 !== self::$options['ip']['active'] ) {
+			$ip = self::get_ip();
+			if ( false !== ( $ip ) ) {
+				foreach ( self::$options['ip']['blacklist'] as $net ) {
+					if ( self::cidr_match( $ip, $net ) ) {
+						return true;
+					}
+				}
+			}
+		}
+
+		// User agent filter (since 1.6).
+		if ( self::apply_single_filter( self::$options['ua'], array( __CLASS__, 'get_user_agent' ) ) ) {
+			return true;
+		}
+
+		// Skip and continue (return NULL), if all filters are inactive.
+		return null;
+	}
+
+	/**
+	 * Apply a single filter, if active.
+	 *
+	 * @param array    $config   Configuration array from plugin options.
+	 * @param callable $value_fn Extractor function for filterable value.
+	 *
+	 * @return bool TRUE if referer matches filter.
+	 *
+	 * @since 1.6 Extracted from "apply_blacklist_filter" to reduce redundancies.
+	 */
+	private static function apply_single_filter( $config, $value_fn ) {
+		// Is the filter active?
+		if ( ! isset( $config['active'] ) || 0 === $config['active'] ) {
+			return false;
+		}
+
+		// Extract the filterable value.
+		$value = call_user_func( $value_fn );
+
+		$mode = isset( $config['regexp'] ) ? intval( $config['regexp'] ) : self::MODE_NORMAL;
+
+		switch ( $mode ) {
+			case self::MODE_REGEX:
+			case self::MODE_REGEX_CI:
+				// Regular Expression filtering since 1.3.0.
+
+				// Merge given regular expressions into one.
+				$regexp = self::regex(
+					array_keys( $config['blacklist'] ),
+					self::MODE_REGEX_CI === $config['regexp']
+				);
+
+				// Check filter (no return to continue filtering #12).
+				if ( 1 === preg_match( $regexp, $value ) ) {
+					return true;
+				}
+				break;
+
+			case self::MODE_KEYWORD:
+				// Keyword filter since 1.5.0 (#15).
+				foreach ( array_keys( $config['blacklist'] ) as $keyword ) {
+					if ( false !== strpos( strtolower( $value ), strtolower( $keyword ) ) ) {
+						return true;
+					}
+				}
+
+				break;
+
+			default:
+				// Standard exact filter.
+				if ( isset( $config['blacklist'][ $value ] ) ) {
+					return true;
+				}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Preprocess regular expression provided by the user, i.e. add delimiters and optional ci flag.
+	 *
+	 * @param string|array $expression       Original expression string or array of expressions.
+	 * @param string|array $case_insensitive Make expression match case-insensitive.
+	 *
+	 * @return string Preprocessed expression ready for preg_match().
+	 */
+	protected static function regex( $expression, $case_insensitive ) {
+		$res = '/';
+		if ( is_string( $expression ) ) {
+			$res .= str_replace( '/', '\/', $expression );
+		} elseif ( is_array( $expression ) ) {
+			$res .= implode(
+				'|',
+				array_map(
+					function ( $e ) {
+						return str_replace( '/', '\/', $e );
+					},
+					$expression
+				)
+			);
+		}
+		$res .= '/';
+		if ( $case_insensitive ) {
+			$res .= 'i';
+		}
+
+		return $res;
+	}
+
+	/**
+	 * Helper method to determine the client's referer.
+	 *
+	 * @return string The referer.
+	 */
+	private static function get_referer() {
+		$referer = wp_get_raw_referer();
+		if ( ! $referer ) {
+			$referer = '';
+		}
+
+		return $referer;
+	}
+
+	/**
+	 * Helper method to determine the host part of the client's referer.
+	 *
+	 * @return string Referer domain.
+	 */
+	private static function get_referer_domain() {
+		$referer = wp_parse_url( self::get_referer() );
+
+		return strtolower( ( isset( $referer['host'] ) ? $referer['host'] : '' ) );
+	}
+
+	/**
+	 * Helper method to determine the client's referer.
+	 *
+	 * @return string The referer.
+	 */
+	private static function get_target() {
+		if ( isset( $_SERVER['REQUEST_URI'] ) ) {
+			$target = filter_var( wp_unslash( $_SERVER['REQUEST_URI'] ), FILTER_SANITIZE_URL );
+			if ( $target ) {
+				return $target;
+			}
+		}
+
+		return '';
+	}
+
+	/**
+	 * Helper method to determine the client's IP address.
+	 *
+	 * If a proxy is used, the X-Real-IP or X-Forwarded-For header is checked, otherwise the default remote address.
+	 * For performance reasons only the most common flags are checked. This might be even reduce by user configuration.
+	 * Maybe some community feedback will ease the decision on that.
+	 *
+	 * @return string|bool the client's IP address or FALSE, if none could be determined.
+	 */
+	private static function get_ip() {
+		foreach (
+
+			/*
+			 * There are more fields, that could possibly be checked, but we only consider the most common for now:
+			 * HTTP_CLIENT_IP, HTTP_X_REAL_IP, HTTP_X_FORWARDED_FOR, HTTP_X_FORWARDED,
+			 * HTTP_X_CLUSTER_CLIENT_IP, HTTP_FORWARDED_FOR, HTTP_FORWARDED, REMOTE_ADDR
+			 */
+			array(
+				'HTTP_X_REAL_IP',
+				'HTTP_X_FORWARDED_FOR',
+				'REMOTE_ADDR',
+			) as $k
+		) {
+			if ( isset( $_SERVER[ $k ] ) ) {
+				// phpcs:ignore
+				foreach ( explode( ',', $_SERVER[ $k ] ) as $ip ) {
+					if ( false !== filter_var( $ip, FILTER_VALIDATE_IP ) ) {
+						return $ip;
+					}
+				}
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Helper method to determine the user agent.
+	 *
+	 * @return string The user agent string.
+	 */
+	private static function get_user_agent() {
+		if ( ! empty( $_SERVER['HTTP_USER_AGENT'] ) ) {
+			$user_agent = filter_var( wp_unslash( $_SERVER['HTTP_USER_AGENT'] ), FILTER_SANITIZE_STRING );
+			if ( $user_agent ) {
+				return $user_agent;
+			}
+		}
+
+		return '';
+	}
+
+	/**
+	 * Helper function to check if an IP address matches a given subnet.
+	 *
+	 * @param string $ip  IP address to check.
+	 * @param string $net IP address or subnet in CIDR notation.
+	 *
+	 * @return bool TRUE, if the given IP addresses matches the given subnet.
+	 */
+	private static function cidr_match( $ip, $net ) {
+		if ( substr_count( $net, ':' ) > 1 ) {  // Check for IPv6.
+			if ( ! ( ( extension_loaded( 'sockets' ) && defined( 'AF_INET6' ) ) || inet_pton( '::1' ) ) ) {
+				return false;
+			}
+
+			if ( false !== strpos( $net, '/' ) ) {   // Parse CIDR subnet.
+				list( $base, $mask ) = explode( '/', trim( $net ), 2 );
+
+				if ( ! is_numeric( $mask ) ) {
+					return false;
+				} else {
+					$mask = (int) $mask;
+				}
+
+				if ( $mask < 1 || $mask > 128 ) {
+					return false;
+				}
+			} else {
+				$base = $net;
+				$mask = 128;
+			}
+
+			$bytes_addr = unpack( 'n*', inet_pton( $base ) );
+			$bytes_est  = unpack( 'n*', inet_pton( $ip ) );
+
+			if ( ! $bytes_addr || ! $bytes_est ) {
+				return false;
+			}
+
+			$ceil = ceil( $mask / 16 );
+			for ( $i = 1; $i <= $ceil; ++ $i ) {
+				$left   = $mask - 16 * ( $i - 1 );
+				$left   = ( $left <= 16 ) ? $left : 16;
+				$mask_b = ~( 0xffff >> $left ) & 0xffff;
+				if ( ( $bytes_addr[ $i ] & $mask_b ) !== ( $bytes_est[ $i ] & $mask_b ) ) {
+					return false;
+				}
+			}
+
+			return true;
+		} else {    // Check for IPv4.
+			if ( ! filter_var( $ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4 ) ) {
+				return false;
+			}
+
+			if ( false !== strpos( $net, '/' ) ) {  // Parse CIDR subnet.
+				list( $base, $mask ) = explode( '/', $net, 2 );
+
+				if ( '0' === $mask ) {
+					return filter_var( $base, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4 );
+				}
+
+				if ( $mask < 0 || $mask > 32 ) {
+					return false;
+				}
+			} else {    // Use single address.
+				$base = $net;
+				$mask = 32;
+			}
+
+			return ( 0 === substr_compare( sprintf( '%032b', ip2long( $ip ) ), sprintf( '%032b', ip2long( $base ) ), 0, $mask ) );
+		}
+	}
+}

inc/statifyblacklist.class.php

@@ -1,146 +0,0 @@
-<?php
-
-/* Quit */
-defined( 'ABSPATH' ) OR exit;
-
-/**
- * Statify Blacklist
- *
- * @since 1.0.0
- */
-class StatifyBlacklist {
-	/**
-	 * Plugin options
-	 *
-	 * @var array
-	 * @since   1.0.0
-	 */
-	public static $_options;
-
-	/**
-	 * Multisite Status
-	 *
-	 * @var bool
-	 * @since   1.0.0
-	 */
-	public static $multisite;
-
-	/**
-	 * Class self initialize
-	 *
-	 * @since   1.0.0
-	 */
-	public static function instance() {
-		new self();
-	}
-
-	/**
-	 * Class constructor
-	 *
-	 * @since   1.0.0
-	 * @changed 1.2.1
-	 */
-	public function __construct() {
-		/* Skip on autosave or AJAX */
-		if ( ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) OR ( defined( 'DOING_AJAX' ) && DOING_AJAX ) ) {
-			return;
-		}
-
-		/* Plugin options */
-		self::update_options();
-
-		/* Get multisite status */
-		self::$multisite = ( is_multisite() && array_key_exists( STATIFYBLACKLIST_BASE, (array) get_site_option( 'active_sitewide_plugins' ) ) );
-
-		/* Add Filter to statify hook if enabled */
-		if ( self::$_options['active_referer'] != 0 ) {
-			add_filter( 'statify_skip_tracking', array( 'StatifyBlacklist', 'apply_blacklist_filter' ) );
-		}
-
-		/* Admin only filters */
-		if ( is_admin() ) {
-			/* Load Textdomain (only needed for backend */
-			load_plugin_textdomain( 'statifyblacklist', false, STATIFYBLACKLIST_DIR . '/lang/' );
-
-			/* Add actions */
-			add_action( 'wpmu_new_blog', array( 'StatifyBlacklist_Install', 'init_site' ) );
-			add_action( 'delete_blog', array( 'StatifyBlacklist_System', 'init_site' ) );
-			add_filter( 'plugin_row_meta', array( 'StatifyBlacklist_Admin', 'plugin_meta_link' ), 10, 2 );
-
-			if ( is_multisite() ) {
-				add_action( 'network_admin_menu', array( 'StatifyBlacklist_Admin', '_add_menu_page' ) );
-				add_filter( 'network_admin_plugin_action_links', array(
-					'StatifyBlacklist_Admin',
-					'plugin_actions_links'
-				), 10, 2 );
-			} else {
-				add_action( 'admin_menu', array( 'StatifyBlacklist_Admin', '_add_menu_page' ) );
-				add_filter( 'plugin_action_links', array( 'StatifyBlacklist_Admin', 'plugin_actions_links' ), 10, 2 );
-			}
-		}
-
-		/* CronJob to clean up database */
-		if ( defined( 'DOING_CRON' ) && DOING_CRON ) {
-			if ( self::$_options['cron_referer'] == 1 ) {
-				add_action( 'statify_cleanup', array( 'StatifyBlacklist_Admin', 'cleanup_database' ) );
-			}
-		}
-	}
-
-	/**
-	 * Update options
-	 *
-	 * @param  $options array  New options to save
-	 *
-	 * @since   1.0.0
-	 * @changed 1.1.1
-	 */
-	public static function update_options( $options = null ) {
-		self::$_options = wp_parse_args(
-			get_option( 'statify-blacklist' ),
-			array(
-				'active_referer' => 0,
-				'cron_referer'   => 0,
-				'referer'        => array(),
-				'referer_regexp' => 0
-			)
-		);
-	}
-
-	/**
-	 * Apply the blacklist filter if active
-	 *
-	 * @return  TRUE if referer matches blacklist.
-	 *
-	 * @since   1.0.0
-	 * @changed 1.3.0
-	 */
-	public static function apply_blacklist_filter() {
-		/* Skip if blacklist is inactive */
-		if ( self::$_options['active_referer'] != 1 ) {
-			return false;
-		}
-
-		/* Regular Expression filtering since 1.3.0 */
-		if ( isset(self::$_options['referer_regexp']) && self::$_options['referer_regexp'] > 0 ) {
-			/* Get full referer string */
-			$referer = ( isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : '' );
-			/* Merge given regular expressions into one */
-			$regexp = '/' . implode( "|", array_keys( self::$_options['referer'] ) ) . '/';
-			if ( self::$_options['referer_regexp'] == 2 ) {
-				$regexp .= 'i';
-			}
-			/* Check blacklist */
-			return preg_match( $regexp, $referer) === 1;
-		} else {
-			/* Extract relevant domain parts */
-			$referer = strtolower( ( isset( $_SERVER['HTTP_REFERER'] ) ? parse_url( $_SERVER['HTTP_REFERER'], PHP_URL_HOST ) : '' ) );
-
-			/* Get blacklist */
-			$blacklist = self::$_options['referer'];
-
-			/* Check blacklist */
-			return isset( $blacklist[ $referer ] );
-		}
-	}
-}

inc/statifyblacklist_admin.class.php

@@ -1,177 +0,0 @@
-<?php
-
-/* Quit */
-defined( 'ABSPATH' ) OR exit;
-
-/**
- * Statify Blacklist admin configuration
- *
- * @since 1.0.0
- */
-class StatifyBlacklist_Admin extends StatifyBlacklist {
-	/**
-	 * Update options
-	 *
-	 * @param  $options array  New options to save
-	 * @return mixed  array of sanitized array on errors, FALSE if there were none
-	 * @since   1.1.1
-	 * @changed 1.3.0
-	 */
-	public static function update_options( $options = null ) {
-		if ( isset( $options ) && current_user_can( 'manage_options' ) ) {
-			/* Sanitize URLs and remove empty inputs */
-			$givenReferer = $options['referer'];
-			if ($options['referer_regexp'] == 0)
-				$sanitizedReferer = self::sanitizeURLs( $givenReferer );
-			else
-				$sanitizedReferer = $givenReferer;
-
-			/* Abort on errors */
-			if ( ! empty( array_diff( $givenReferer, $sanitizedReferer ) ) ) {
-				return $sanitizedReferer;
-			}
-
-			/* Update database on success */
-			if ( ( is_multisite() && array_key_exists( STATIFYBLACKLIST_BASE, (array) get_site_option( 'active_sitewide_plugins' ) ) ) ) {
-				update_site_option( 'statify-blacklist', $options );
-			} else {
-				update_option( 'statify-blacklist', $options );
-			}
-		}
-
-		/* Refresh options */
-		parent::update_options( $options );
-
-		return false;
-	}
-
-	/**
-	 * Add configuration page to admin menu
-	 *
-	 * @since   1.0.0
-	 */
-	public function _add_menu_page() {
-		$title = __( 'Statify Blacklist', 'statify-blacklist' );
-		if ( self::$multisite ) {
-			add_submenu_page( 'settings.php', $title, $title, 'manage_network_plugins', 'statify-blacklist-settings', array(
-				'StatifyBlacklist_Admin',
-				'settings_page'
-			) );
-		} else {
-			add_submenu_page( 'options-general.php', $title, $title, 'manage_options', 'statify-blacklist', array(
-				'StatifyBlacklist_Admin',
-				'settings_page'
-			) );
-		}
-
-	}
-
-	public static function settings_page() {
-		include STATIFYBLACKLIST_DIR . '/views/settings_page.php';
-	}
-
-	/**
-	 * Add plugin meta links
-	 *
-	 * @param $links
-	 * @param $file
-	 *
-	 * @return array
-	 *
-	 * @since   1.0.0
-	 */
-	public static function plugin_meta_link( $links, $file ) {
-		if ( $file == STATIFYBLACKLIST_BASE ) {
-			$links[] = '<a href="https://github.com/stklcode/statify-blacklist">GitHub</a>';
-		}
-
-		return $links;
-	}
-
-	/**
-	 * Add plugin action links
-	 *
-	 * @param   array $input Registered links
-	 *
-	 * @return  array           Merged links
-	 *
-	 * @since   1.0.0
-	 */
-	public static function plugin_actions_links( $links, $file ) {
-		$base = self::$multisite ? network_admin_url( 'settings.php' ) : admin_url( 'options-general.php' );
-
-		if ( $file == STATIFYBLACKLIST_BASE && current_user_can( 'manage_options' ) ) {
-			array_unshift(
-				$links,
-				sprintf( '<a href="%s">%s</a>', esc_attr( add_query_arg( 'page', 'statify-blacklist', $base ) ), __( 'Settings' ) )
-			);
-		}
-
-		return $links;
-	}
-
-	/**
-	 * Filter database for cleanup.
-	 *
-	 * @since   1.1.0
-	 * @changed 1.3.0
-	 */
-	public static function cleanup_database() {
-		/* Check user permissions */
-		if ( ! current_user_can( 'manage_options' ) && ! ( defined( 'DOING_CRON' ) && DOING_CRON ) ) {
-			die( _e( 'Are you sure you want to do this?' ) );
-		}
-
-		global $wpdb;
-
-		if ( isset( self::$_options['referer_regexp'] ) && self::$_options['referer_regexp'] > 0 ) {
-			/* Merge given regular expressions into one */
-			$refererRegexp = implode( "|", array_keys( self::$_options['referer'] ) );
-		} else {
-			/* Sanitize URLs */
-			$referer = self::sanitizeURLs( self::$_options['referer'] );
-
-			/* Build filter regexp */
-			$refererRegexp = str_replace( '.', '\.', implode( '|', array_flip( $referer ) ) );
-		}
-
-		if ( ! empty( $refererRegexp ) ) {
-			/* Execute filter on database */
-			$wpdb->query(
-				$wpdb->prepare( "DELETE FROM `$wpdb->statify` WHERE "
-				                . ( ( self::$_options['referer_regexp'] == 1 ) ? " BINARY " : "" )
-				                . "referrer REGEXP %s", $refererRegexp )
-			);
-
-			/* Optimize DB */
-			$wpdb->query( "OPTIMIZE TABLE `$wpdb->statify`" );
-
-			/* Delete transient statify data */
-			delete_transient( 'statify_data' );
-		}
-	}
-
-
-	/**
-	 * Sanitize URLs and remove empty results
-	 *
-	 * @param $urls array   given array of URLs
-	 *
-	 * @return array  sanitized array
-	 *
-	 * @since    1.1.1
-	 * @changed  1.2.0
-	 */
-	private static function sanitizeURLs( $urls ) {
-		return array_flip(
-			array_filter(
-				array_map(
-					function ( $r ) {
-						return preg_replace( '/[^\da-z\.-]/i', '', filter_var( $r, FILTER_SANITIZE_URL ) );
-					},
-					array_flip( $urls )
-				)
-			)
-		);
-	}
-}

inc/statifyblacklist_system.class.php

@@ -1,114 +0,0 @@
-<?php
-
-/* Quit */
-defined( 'ABSPATH' ) OR exit;
-
-/**
- * Statify Blacklist system configuration
- *
- * @since 1.0.0
- */
-class StatifyBlacklist_System extends StatifyBlacklist {
-
-	const VERSION_MAIN = 1.3;
-
-	/**
-	 * Plugin install handler.
-	 *
-	 * @since 1.0.0
-	 *
-	 * @param bool $network_wide Whether the plugin was activated network-wide or not.
-	 */
-	public static function install( $network_wide = false ) {
-		global $wpdb;
-
-		// Create tables for each site in a network.
-		if ( is_multisite() && $network_wide ) {
-			// Todo: Use get_sites() in WordPress 4.6+
-			$ids = $wpdb->get_col( "SELECT blog_id FROM `$wpdb->blogs`" );
-
-			foreach ( $ids as $site_id ) {
-				switch_to_blog( $site_id );
-				add_option(
-					'statify-blacklist',
-					array(
-						'activate-referer' => 0,
-						'referer'          => array()
-					)
-				);
-			}
-
-			restore_current_blog();
-		} else {
-			add_option(
-				'statify-blacklist',
-				array(
-					'activate-referer' => 0,
-					'referer'          => array()
-				)
-			);
-		}
-	}
-
-
-	/**
-	 * Plugin uninstall handler.
-	 *
-	 * @since 1.0.0
-	 */
-	public static function uninstall() {
-		global $wpdb;
-
-		if ( is_multisite() ) {
-			$old = get_current_blog_id();
-
-			// Todo: Use get_sites() in WordPress 4.6+
-			$ids = $wpdb->get_col( "SELECT blog_id FROM `$wpdb->blogs`" );
-
-			foreach ( $ids as $id ) {
-				switch_to_blog( $id );
-				delete_option( 'statify-blacklist' );
-			}
-
-			switch_to_blog( $old );
-		}
-
-		delete_option( 'statify-blacklist' );
-	}
-
-
-	/**
-	 * Upgrade plugin options.
-	 *
-	 * @since   1.2.0
-	 * @changed 1.3.0
-	 */
-	public static function upgrade() {
-		self::update_options();
-		/* Check if config array is not associative (pre 1.2.0) */
-		if ( array_keys( self::$_options['referer'] ) === range( 0, count( self::$_options['referer'] ) - 1 ) ) {
-			/* Flip referer array to make domains keys */
-			$options            = self::$_options;
-			$options['referer'] = array_flip( self::$_options['referer'] );
-			if ( ( is_multisite() && array_key_exists( STATIFYBLACKLIST_BASE, (array) get_site_option( 'active_sitewide_plugins' ) ) ) ) {
-				update_site_option( 'statify-blacklist', $options );
-			} else {
-				update_option( 'statify-blacklist', $options );
-			}
-		}
-
-		/* Check if version is set (not before 1.3.0) */
-		if ( ! isset( self::$_options['version'] ) ) {
-			$options = self::$_options;
-			/* Set version */
-			$options['version'] = self::VERSION_MAIN;
-			/* Add regular expression option (as of 1.3) */
-			$options['referer_regexp'] = 0;
-			if ( ( is_multisite() && array_key_exists( STATIFYBLACKLIST_BASE, (array) get_site_option( 'active_sitewide_plugins' ) ) ) ) {
-				update_site_option( 'statify-blacklist', $options );
-			} else {
-				update_option( 'statify-blacklist', $options );
-			}
-		}
-	}
-}

package.json

@@ -0,0 +1,7 @@
+{
+  "name": "statify-blacklist",
+  "version": "1.6.0",
+  "description": "A filter extension for the famous Statify WordPress plugin",
+  "author": "Stefan Kalscheuer",
+  "license": "GPL-2.0+"
+}

phpcs.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0"?>
+<ruleset name="StatifyBlacklist">
+	<description>Derived from WordPress Coding Standard</description>
+
+	<arg value="psv"/>
+	<arg name="colors"/>
+
+	<!-- Files to sniff -->
+	<file>statify-blacklist.php</file>
+	<file>inc</file>
+	<file>views</file>
+
+	<!-- Compliance with WordPress Coding Standard -->
+	<config name="minimum_supported_wp_version" value="4.7"/>
+	<rule ref="WordPress">
+		<!-- Direct queries used to clean up statify table. -->
+		<exclude name="WordPress.DB.DirectDatabaseQuery.DirectQuery"/>
+		<exclude name="WordPress.DB.DirectDatabaseQuery.NoCaching"/>
+	</rule>
+
+	<rule ref="WordPress.WP.I18n">
+		<properties>
+			<property name="text_domain" type="array" value="statify-blacklist"/>
+		</properties>
+	</rule>
+
+	<!-- PHP compatibility level -->
+	<config name="testVersion" value="5.5-"/>
+	<rule ref="PHPCompatibilityWP"/>
+</ruleset>

phpunit.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<phpunit bootstrap="./vendor/autoload.php">
+	<testsuites>
+		<testsuite name="Statify Blacklist TestSuite">
+			<directory suffix="_Test.php">./test/</directory>
+		</testsuite>
+	</testsuites>
+	<filter>
+		<whitelist processUncoveredFilesFromWhitelist="true">
+			<directory suffix=".php">./inc/</directory>
+		</whitelist>
+	</filter>
+	<logging>
+		<log type="coverage-clover" target="tests-clover.xml"/>
+		<log type="junit" target="tests-junit.xml"/>
+	</logging>
+</phpunit>

statify-blacklist.php

@@ -1,52 +1,139 @@
 <?php
-/*
-Plugin Name: Statify Blacklist
-Description: Extension for the statify plugin to add a customizable blacklists.
-Text Domain: statify-blacklist
-Domain Path: /lang
-Author:      Stefan Kalscheuer
-Author URI:  https://stklcode.de
-Plugin URI:  https://wordpress.org/plugins/statify-blacklist
-License:     GPLv3 or later
-Version:     1.3.0
-*/
+/**
+ * Statify Filter
+ *
+ * @package     PluginPackage
+ * @author      Stefan Kalscheuer <stefan@stklcode.de>
+ * @license     GPL-2.0+
+ *
+ * @wordpress-plugin
+ * Plugin Name: Statify Filter
+ * Plugin URI:  https://wordpress.org/plugins/statify-blacklist/
+ * Description: Extension for the Statify plugin to add customizable filters. (formerly "Statify Blacklist)
+ * Version:     1.6.0
+ * Author:      Stefan Kalscheuer (@stklcode)
+ * Author URI:  https://www.stklcode.de
+ * Text Domain: statify-blacklist
+ * License:     GPLv2 or later
+ *
+ * Statify Filter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * any later version.
+ *
+ * Statify Filter is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Statify Filter. If not, see https://www.gnu.org/licenses/gpl-2.0.html.
+ */
 
-/* Quit */
-defined( 'ABSPATH' ) OR exit;
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
 
-/*  Constants */
+// Constants.
 define( 'STATIFYBLACKLIST_FILE', __FILE__ );
 define( 'STATIFYBLACKLIST_DIR', dirname( __FILE__ ) );
 define( 'STATIFYBLACKLIST_BASE', plugin_basename( __FILE__ ) );
 
-/* System Hooks */
-add_action( 'plugins_loaded', array( 'StatifyBlacklist', 'instance' ) );
+// Check for compatibility.
+if ( statify_blacklist_compatibility_check() ) {
+	// System Hooks.
+	add_action( 'plugins_loaded', array( 'StatifyBlacklist', 'init' ) );
 
-register_activation_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'install' ) );
+	register_activation_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'install' ) );
 
-register_uninstall_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'uninstall' ) );
+	register_uninstall_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'uninstall' ) );
 
-/* Upgrade hook */
-register_activation_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'upgrade' ) );
+	// Upgrade hook.
+	register_activation_hook( STATIFYBLACKLIST_FILE, array( 'StatifyBlacklist_System', 'upgrade' ) );
 
-/* Autoload */
-spl_autoload_register( 'statifyBlacklist_autoload' );
+	// Autoload.
+	spl_autoload_register( 'statify_blacklist_autoload' );
+} else {
+	// Disable plugin, if active.
+	add_action( 'admin_init', 'statify_blacklist_disable' );
+}
 
 /**
  * Autoloader for StatifyBlacklist classes.
  *
- * @param $class
+ * @param string $class Name of the class to load.
  *
  * @since 1.0.0
  */
-function statifyBlacklist_autoload( $class ) {
+function statify_blacklist_autoload( $class ) {
 	$plugin_classes = array(
 		'StatifyBlacklist',
 		'StatifyBlacklist_Admin',
-		'StatifyBlacklist_System'
+		'StatifyBlacklist_System',
 	);
 
-	if ( in_array( $class, $plugin_classes ) ) {
-		require_once( sprintf( '%s/inc/%s.class.php', STATIFYBLACKLIST_DIR, strtolower( $class ) ) );
+	if ( in_array( $class, $plugin_classes, true ) ) {
+		require_once sprintf(
+			'%s/inc/class-%s.php',
+			STATIFYBLACKLIST_DIR,
+			strtolower( str_replace( '_', '-', $class ) )
+		);
 	}
 }
+
+/**
+ * Check for compatibility with PHP and WP version.
+ *
+ * @since 1.5.0
+ *
+ * @return boolean Whether minimum WP and PHP versions are met.
+ */
+function statify_blacklist_compatibility_check() {
+	return version_compare( $GLOBALS['wp_version'], '4.7', '>=' ) &&
+		version_compare( phpversion(), '5.5', '>=' );
+}
+
+/**
+ * Disable plugin if active and incompatible.
+ *
+ * @since 1.5.0
+ *
+ * @return void
+ */
+function statify_blacklist_disable() {
+	if ( is_plugin_active( STATIFYBLACKLIST_BASE ) ) {
+		deactivate_plugins( STATIFYBLACKLIST_BASE );
+		add_action( 'admin_notices', 'statify_blacklist_disabled_notice' );
+		// phpcs:disable WordPress.Security.NonceVerification.Recommended
+		if ( isset( $_GET['activate'] ) ) {
+			unset( $_GET['activate'] );
+		}
+		// phpcs:enable
+	}
+}
+
+/**
+ * Admin notification for unmet requirements.
+ *
+ * @since 1.5.0
+ *
+ * @return void
+ */
+function statify_blacklist_disabled_notice() {
+	echo '<div class="notice notice-error is-dismissible"><p><strong>';
+	printf(
+		/* translators: minimum version numbers for WordPress and PHP inserted at placeholders */
+		esc_html__( 'Statify Filter requires at least WordPress %1$s and PHP %2$s.', 'statify-blacklist' ),
+		'4.7',
+		'5.5'
+	);
+	echo '<br>';
+	printf(
+		/* translators: current version numbers for WordPress and PHP inserted at placeholders */
+		esc_html__( 'Your site is running WordPress %1$s on PHP %2$s, thus the plugin has been disabled.', 'statify-blacklist' ),
+		esc_html( $GLOBALS['wp_version'] ),
+		esc_html( phpversion() )
+	);
+	echo '</strong></p></div>';
+}

test/StatifyBlacklistTest.php

@@ -1,95 +0,0 @@
-<?php
-
-const ABSPATH = false;
-require_once( '../inc/statifyblacklist.class.php' );
-
-/**
- * Class StatifyBlacklistTest
- *
- * PHPUnit test class for StatifyBlacklist
- */
-class StatifyBlacklistTest extends PHPUnit_Framework_TestCase {
-
-	public function testFilter() {
-		/* Prepare Options: 2 blacklisted domains, disabled */
-		StatifyBlacklist::$_options = array(
-			'active_referer' => 0,
-			'cron_referer'   => 0,
-			'referer'        => array(
-				'example.com' => 0,
-				'example.net' => 1
-			)
-		);
-
-		/* No multisite */
-		StatifyBlacklist::$multisite = false;
-
-		/* No referer */
-		unset( $_SERVER['HTTP_REFERER'] );
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-		/* Non-blacklisted referer */
-		$_SERVER['HTTP_REFERER'] = 'http://example.org';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-		/* Blacklisted referer */
-		$_SERVER['HTTP_REFERER'] = 'http://example.com';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-		/* Blacklisted referer with path */
-		$_SERVER['HTTP_REFERER'] = 'http://example.net/foo/bar.html';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-
-		/* Activate filter and run tests again */
-		StatifyBlacklist::$_options['active_referer'] = 1;
-
-		unset( $_SERVER['HTTP_REFERER'] );
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-
-		$_SERVER['HTTP_REFERER'] = 'http://example.org';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-
-		$_SERVER['HTTP_REFERER'] = 'http://example.com';
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-
-		$_SERVER['HTTP_REFERER'] = 'http://example.net/foo/bar.html';
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-	}
-
-	public function testRegexFilter() {
-		/* Prepare Options: 2 regular expressions */
-		StatifyBlacklist::$_options = array(
-			'active_referer' => 1,
-			'cron_referer'   => 0,
-			'referer'        => array(
-				'example.[a-z]+' => 0,
-				'test' => 1
-			),
-			'referer_regexp' => 1
-		);
-
-		/* No multisite */
-		StatifyBlacklist::$multisite = false;
-
-		/* No referer */
-		unset( $_SERVER['HTTP_REFERER'] );
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-		/* Non-blacklisted referer */
-		$_SERVER['HTTP_REFERER'] = 'http://not.evil';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-		/* Blacklisted referer */
-		$_SERVER['HTTP_REFERER'] = 'http://example.com';
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-		/* Blacklisted referer with path */
-		$_SERVER['HTTP_REFERER'] = 'http://foobar.net/test/me';
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-		/* Matching both */
-		$_SERVER['HTTP_REFERER'] = 'http://example.net/test/me';
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-		/* Mathinc with wrong case */
-		$_SERVER['HTTP_REFERER'] = 'http://eXaMpLe.NeT/tEsT/mE';
-		$this->assertFalse( StatifyBlacklist::apply_blacklist_filter() );
-
-		/* Set RegExp filter to case insensitive */
-		StatifyBlacklist::$_options['referer_regexp'] = 2;
-		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
-	}
-
-}

test/StatifyBlacklist_Test.php

@@ -0,0 +1,789 @@
+<?php
+/**
+ * Statify Filter: Unit Test
+ *
+ * This is a PHPunit test class for the plugin's functionality
+ *
+ * @package    Statify_Blacklist
+ * @subpackage Admin
+ * @since      1.3.0
+ */
+
+/**
+ * Simulating the ABSPATH constant.
+ *
+ * @since 1.3.0
+ * @var bool ABSPATH
+ */
+const ABSPATH = false;
+
+/**
+ * The StatifyBlacklist base class.
+ */
+require_once __DIR__ . '/../inc/class-statifyblacklist.php';
+
+/**
+ * The StatifyBlacklist system class.
+ */
+require_once __DIR__ . '/../inc/class-statifyblacklist-system.php';
+
+/**
+ * The StatifyBlacklist admin class.
+ */
+require_once __DIR__ . '/../inc/class-statifyblacklist-admin.php';
+
+/**
+ * Class StatifyBlacklistTest.
+ *
+ * PHPUnit test class for StatifyBlacklist.
+ *
+ * @since 1.3.0
+ */
+class StatifyBlacklist_Test extends PHPUnit\Framework\TestCase {
+
+	/**
+	 * Test simple referer filter.
+	 *
+	 * @return void
+	 */
+	public function test_referer_filter() {
+		// Prepare Options: 2 filtered domains, disabled.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => 0,
+				'blacklist' => array(
+					'example.com' => 0,
+					'example.net' => 1,
+				),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => 0,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// No referer.
+		unset( $_SERVER['HTTP_REFERER'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://example.org';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://example.com';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer with path.
+		$_SERVER['HTTP_REFERER'] = 'http://example.net/foo/bar.html';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Activate filter and run tests again.
+		StatifyBlacklist::$options['referer']['active'] = 1;
+
+		unset( $_SERVER['HTTP_REFERER'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		$_SERVER['HTTP_REFERER'] = 'http://example.org';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		$_SERVER['HTTP_REFERER'] = 'http://example.com';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+
+		$_SERVER['HTTP_REFERER'] = 'http://example.net/foo/bar.html';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+	/**
+	 * Test referer filter using regular expressions.
+	 *
+	 * @return void
+	 */
+	public function test_referer_regex_filter() {
+		// Prepare Options: 2 regular expressions.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 1,
+				'cron'      => 0,
+				'regexp'    => 1,
+				'blacklist' => array(
+					'example.[a-z]+' => 0,
+					'test'           => 1,
+				),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => 0,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// No referer.
+		unset( $_SERVER['HTTP_REFERER'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://not.evil';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://example.com';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer with path.
+		$_SERVER['HTTP_REFERER'] = 'http://foobar.net/test/me';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Matching both.
+		$_SERVER['HTTP_REFERER'] = 'http://example.net/test/me';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Matching with wrong case.
+		$_SERVER['HTTP_REFERER'] = 'http://eXaMpLe.NeT/tEsT/mE';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Set RegExp filter to case insensitive.
+		StatifyBlacklist::$options['referer']['regexp'] = 2;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+	/**
+	 * Test referer filter using keywords.
+	 *
+	 * @return void
+	 */
+	public function test_referer_keyword_filter() {
+		// Prepare Options: 2 regular expressions.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 1,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_KEYWORD,
+				'blacklist' => array(
+					'example' => 0,
+					'test'    => 1,
+				),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// No referer.
+		unset( $_SERVER['HTTP_REFERER'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://not.evil';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer.
+		$_SERVER['HTTP_REFERER'] = 'http://example.com';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer with path.
+		$_SERVER['HTTP_REFERER'] = 'http://foobar.net/test/me';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Matching both.
+		$_SERVER['HTTP_REFERER'] = 'http://example.net/test/me';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Matching with wrong case.
+		$_SERVER['HTTP_REFERER'] = 'http://eXaMpLe.NeT/tEsT/mE';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+	/**
+	 * Test the upgrade methodology for configuration options.
+	 *
+	 * @return void
+	 */
+	public function test_upgrade() {
+		// Create configuration of version 1.3.
+		$options13 = array(
+			'active_referer' => 1,
+			'cron_referer'   => 0,
+			'referer'        => array(
+				'example.net' => 0,
+				'example.com' => 1,
+			),
+			'referer_regexp' => 0,
+			'version'        => 1.3,
+		);
+
+		// Set options in mock.
+		update_option( 'statify-blacklist', $options13 );
+
+		// Execute upgrade.
+		StatifyBlacklist_System::upgrade();
+
+		// Retrieve updated options.
+		$options_updated = get_option( 'statify-blacklist' );
+
+		// Verify size against default options (no junk left).
+		$this->assertEquals( 4, count( $options_updated ) );
+		$this->assertEquals( 4, count( $options_updated['referer'] ) );
+		$this->assertEquals( 4, count( $options_updated['target'] ) );
+		$this->assertEquals( 2, count( $options_updated['ip'] ) );
+
+		// Verify that original attributes are unchanged.
+		$this->assertEquals( $options13['active_referer'], $options_updated['referer']['active'] );
+		$this->assertEquals( $options13['cron_referer'], $options_updated['referer']['cron'] );
+		$this->assertEquals( $options13['referer'], $options_updated['referer']['blacklist'] );
+		$this->assertEquals( $options13['referer_regexp'], $options_updated['referer']['regexp'] );
+
+		// Verify that new attributes are present in config and filled with default values (disabled, empty).
+		$this->assertEquals( 0, $options_updated['target']['active'] );
+		$this->assertEquals( 0, $options_updated['target']['cron'] );
+		$this->assertEquals( 0, $options_updated['target']['regexp'] );
+		$this->assertEquals( array(), $options_updated['target']['blacklist'] );
+		$this->assertEquals( 0, $options_updated['ip']['active'] );
+		$this->assertEquals( array(), $options_updated['ip']['blacklist'] );
+
+		// Verify that version number has changed to current release.
+		$this->assertEquals( StatifyBlacklist::VERSION_MAIN, $options_updated['version'] );
+	}
+
+	/**
+	 * Test CIDR address matching for IP filter (#7).
+	 *
+	 * @return void
+	 */
+	public function test_cidr_match() {
+		// IPv4 tests.
+		$this->assertTrue( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '127.0.0.1', '127.0.0.1' ) ) );
+		$this->assertTrue( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '127.0.0.1', '127.0.0.1/32' ) ) );
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '127.0.0.1', '127.0.0.1/33' )
+			)
+		);
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '127.0.0.1', '127.0.0.1/-1' )
+			)
+		);
+		$this->assertTrue(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '192.0.2.123', '192.0.2.0/24' )
+			)
+		);
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '192.0.3.123', '192.0.2.0/24' )
+			)
+		);
+		$this->assertTrue(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '192.0.2.123', '192.0.2.120/29' )
+			)
+		);
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '192.0.2.128', '192.0.2.120/29' )
+			)
+		);
+		$this->assertTrue( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '10.11.12.13', '10.0.0.0/8' ) ) );
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '10.11.12.345', '10.0.0.0/8' )
+			)
+		);
+
+		// IPv6 tests.
+		$this->assertTrue( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '::1', '::1' ) ) );
+		$this->assertTrue( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '::1', '::1/128' ) ) );
+		$this->assertFalse( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '::1', '::1/129' ) ) );
+		$this->assertFalse( invoke_static( StatifyBlacklist::class, 'cidr_match', array( '::1', '::1/-1' ) ) );
+		$this->assertTrue(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '2001:db8:a0b:12f0:1:2:3:4', '2001:db8:a0b:12f0::1/64 ' )
+			)
+		);
+		$this->assertTrue(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '2001:db8:a0b:12f0::123:456', '2001:db8:a0b:12f0::1/96 ' )
+			)
+		);
+		$this->assertFalse(
+			invoke_static(
+				StatifyBlacklist::class,
+				'cidr_match',
+				array( '2001:db8:a0b:12f0::1:132:465', '2001:db8:a0b:12f0::1/96 ' )
+			)
+		);
+	}
+
+	/**
+	 * Test sanitization of IP addresses.
+	 *
+	 * @return void
+	 */
+	public function test_sanitize_ips() {
+		// IPv4 tests.
+		$valid   = array( '192.0.2.123', '192.0.2.123/32', '192.0.2.0/24', '192.0.2.128/25' );
+		$invalid = array( '12.34.56.789', '192.0.2.123/33', '192.0.2.123/-1' );
+		$result  = invoke_static( StatifyBlacklist_Admin::class, 'sanitize_ips', array( array_merge( $valid, $invalid ) ) );
+		$this->assertNotFalse( $result );
+
+		/*
+		 * Unfortunately this is necessary as long as we run PHP 5 tests, because "assertInternalType" is deprecated
+		 * as of PHPUnit 8, but "assertIsArray" has been introduces in PHPUnit 7.5 which requires PHP >= 7.1.
+		 */
+		if ( method_exists( $this, 'assertIsArray' ) ) {
+			$this->assertIsArray( $result );
+		} else {
+			$this->assertInternalType( 'array', $result );
+		}
+		$this->assertEquals( $valid, $result );
+
+		// IPv6 tests.
+		$valid   = array(
+			'2001:db8:a0b:12f0::',
+			'2001:db8:a0b:12f0::1',
+			'2001:db8:a0b:12f0::1/128',
+			'2001:db8:a0b:12f0::/64',
+		);
+		$invalid = array(
+			'2001:db8:a0b:12f0::x',
+			'2001:db8:a0b:12f0:::',
+			'2001:fffff:a0b:12f0::1',
+			'2001:db8:a0b:12f0::/129',
+			'1:2:3:4:5:6:7:8:9',
+		);
+		$result  = invoke_static( StatifyBlacklist_Admin::class, 'sanitize_ips', array( array_merge( $valid, $invalid ) ) );
+		$this->assertNotFalse( $result );
+		if ( method_exists( $this, 'assertIsArray' ) ) {
+			$this->assertIsArray( $result );
+		} else {
+			$this->assertInternalType( 'array', $result );
+		}
+		$this->assertEquals( $valid, $result );
+	}
+
+	/**
+	 * Test IP filter (#7).
+	 *
+	 * @return void
+	 */
+	public function test_ip_filter() {
+		// Prepare Options: 2 filtered IPs, disabled.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(
+					'192.0.2.123',
+					'2001:db8:a0b:12f0::1',
+				),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// Set matching IP.
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.123';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Activate filter.
+		StatifyBlacklist::$options['ip']['active'] = 1;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Try matching v6 address.
+		$_SERVER['REMOTE_ADDR'] = '2001:db8:a0b:12f0::1';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-matching addresses.
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.234';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '2001:db8:a0b:12f0::2';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Subnet matching.
+		StatifyBlacklist::$options['ip']['blacklist'] = array(
+			'192.0.2.0/25',
+			'2001:db8:a0b:12f0::/96',
+		);
+		$_SERVER['REMOTE_ADDR']                       = '192.0.2.123';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.234';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '2001:db8:a0b:12f0::5';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '2001:db8:a0b:12f0:0:1111::1';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Filter using proxy header.
+		$_SERVER['REMOTE_ADDR'] = '127.0.0.1';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_X_FORWARDED_FOR'] = '192.0.2.123';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_X_REAL_IP'] = '2001:db8:a0b:12f0:0:1111::1';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_X_REAL_IP'] = '2001:db8:a0b:12f0:0::1';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+	/**
+	 * Test simple target filter.
+	 *
+	 * @return void
+	 */
+	public function test_target_filter() {
+		// Prepare Options: 2 filtered domains, disabled.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(
+					'/excluded/page/' => 0,
+					'/?page_id=3'     => 1,
+				),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// Empty target.
+		unset( $_SERVER['REQUEST_URI'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-filtered targets.
+		$_SERVER['REQUEST_URI'] = '';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/?page_id=1';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Filtered referer.
+		$_SERVER['REQUEST_URI'] = '/excluded/page/';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/?page_id=3';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Activate filter and run tests again.
+		StatifyBlacklist::$options['target']['active'] = 1;
+
+		unset( $_SERVER['REQUEST_URI'] );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		$_SERVER['REQUEST_URI'] = '';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/?page_id=1';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+
+		$_SERVER['REQUEST_URI'] = '/excluded/page/';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/?page_id=3';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/?page_id=3';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+	// TODO: Test target regex filter.
+
+
+	/**
+	 * Test user agent filter (#20).
+	 *
+	 * @return void
+	 */
+	public function test_ua_filter() {
+		// Prepare Options: 2 filtered IPs, disabled.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'target'  => array(
+				'active'    => 0,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'ip'      => array(
+				'active'    => 0,
+				'blacklist' => array(),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(
+					'TestBot/1.23' => 0,
+				),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// Set matching user agent.
+		$_SERVER['HTTP_USER_AGENT'] = 'TestBot/1.23';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Activate filter.
+		StatifyBlacklist::$options['ua']['active'] = 1;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Non-matching addresses.
+		$_SERVER['HTTP_USER_AGENT'] = 'Another Browser 4.5.6 (Linux)';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_USER_AGENT'] = 'TestBot/2.34';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		// Keyword matching.
+		StatifyBlacklist::$options['ua']['blacklist'] = array( 'TestBot' => 0 );
+		StatifyBlacklist::$options['ua']['regexp'] = StatifyBlacklist::MODE_KEYWORD;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// RegEx.
+		StatifyBlacklist::$options['ua']['blacklist'] = array( 'T[a-z]+B[a-z]+' => 0 );
+		StatifyBlacklist::$options['ua']['regexp'] = StatifyBlacklist::MODE_REGEX;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		StatifyBlacklist::$options['ua']['blacklist'] = array( 't[a-z]+' => 0 );
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		StatifyBlacklist::$options['ua']['regexp'] = StatifyBlacklist::MODE_REGEX_CI;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+	}
+
+
+	/**
+	 * Test combined filters.
+	 *
+	 * @since 1.4.4
+	 *
+	 * @return void
+	 */
+	public function test_combined_filters() {
+		// Prepare Options: simple referer + simple target + ip.
+		StatifyBlacklist::$options = array(
+			'referer' => array(
+				'active'    => 1,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(
+					'example.com' => 0,
+				),
+			),
+			'target'  => array(
+				'active'    => 1,
+				'cron'      => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(
+					'/excluded/page/' => 0,
+				),
+			),
+			'ip'      => array(
+				'active'    => 1,
+				'blacklist' => array(
+					'192.0.2.123',
+				),
+			),
+			'ua'      => array(
+				'active'    => 0,
+				'regexp'    => StatifyBlacklist::MODE_NORMAL,
+				'blacklist' => array(),
+			),
+			'version' => StatifyBlacklist::VERSION_MAIN,
+		);
+
+		// No multisite.
+		StatifyBlacklist::$multisite = false;
+
+		// No match.
+		$_SERVER['HTTP_REFERER'] = 'https://example.net';
+		$_SERVER['REQUEST_URI']  = '/normal/page/';
+		$_SERVER['REMOTE_ADDR']  = '192.0.2.234';
+		unset( $_SERVER['HTTP_X_FORWARDED_FOR'] );
+		unset( $_SERVER['HTTP_X_REAL_IP'] );
+
+		// Matching Referer.
+		$_SERVER['HTTP_REFERER'] = 'https://example.com';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Matching target.
+		$_SERVER['HTTP_REFERER'] = 'https://example.net';
+		$_SERVER['REQUEST_URI']  = '/excluded/page/';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+
+		// Matching IP.
+		$_SERVER['REQUEST_URI'] = '/normal/page/';
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.123';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.234';
+
+		// Same for RegExp filters.
+		StatifyBlacklist::$options['referer']['regexp']    = StatifyBlacklist::MODE_REGEX;
+		StatifyBlacklist::$options['referer']['blacklist'] = array( 'example\.com' => 0 );
+		StatifyBlacklist::$options['target']['regexp']     = StatifyBlacklist::MODE_REGEX;
+		StatifyBlacklist::$options['target']['blacklist']  = array( '/excluded/.*' => 0 );
+
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_REFERER'] = 'https://example.com';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		// Check case-insensitive match.
+		$_SERVER['HTTP_REFERER'] = 'https://eXaMpLe.com';
+		$this->assertNull( StatifyBlacklist::apply_blacklist_filter() );
+		StatifyBlacklist::$options['referer']['regexp'] = StatifyBlacklist::MODE_REGEX_CI;
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['HTTP_REFERER'] = 'https://example.net';
+		$_SERVER['REQUEST_URI']  = '/excluded/page/';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REQUEST_URI'] = '/normal/page/';
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.123';
+		$this->assertTrue( StatifyBlacklist::apply_blacklist_filter() );
+		$_SERVER['REMOTE_ADDR'] = '192.0.2.234';
+
+	}
+}
+
+
+/** @ignore */
+function invoke_static( $class, $method_name, $parameters = array() ) {
+	$reflection = new \ReflectionClass( $class );
+	$method     = $reflection->getMethod( $method_name );
+	$method->setAccessible( true );
+
+	return $method->invokeArgs( null, $parameters );
+}
+
+
+// Some mocked WP functions.
+$mock_options   = array();
+$mock_multisite = false;
+
+/** @ignore */
+function is_multisite() {
+	global $mock_multisite;
+
+	return $mock_multisite;
+}
+
+/** @ignore */
+function wp_parse_args( $args, $defaults = '' ) {
+	if ( is_object( $args ) ) {
+		$r = get_object_vars( $args );
+	} elseif ( is_array( $args ) ) {
+		$r =& $args;
+	} else {
+		parse_str( $args, $r );
+	}
+
+	if ( is_array( $defaults ) ) {
+		return array_merge( $defaults, $r );
+	}
+
+	return $r;
+}
+
+/** @ignore */
+function get_option( $option, $default = false ) {
+	global $mock_options;
+
+	return isset( $mock_options[ $option ] ) ? $mock_options[ $option ] : $default;
+}
+
+/** @ignore */
+function update_option( $option, $value, $autoload = null ) {
+	global $mock_options;
+	$mock_options[ $option ] = $value;
+}
+
+/** @ignore */
+function wp_get_raw_referer() {
+	return isset( $_SERVER['HTTP_REFERER'] ) ? $_SERVER['HTTP_REFERER'] : '';
+}
+
+function wp_parse_url( $value ) {
+	return parse_url( $value );
+}
+
+/** @ignore */
+function wp_unslash( $value ) {
+	return is_string( $value ) ? stripslashes( $value ) : $value;
+}

views/settings-page.php

@@ -0,0 +1,488 @@
+<?php
+/**
+ * Statify Filter: Settings View
+ *
+ * This file contains the dynamic HTML skeleton for the plugin's settings page.
+ *
+ * @package    Statify_Blacklist
+ * @subpackage Admin
+ * @since      1.0.0
+ */
+
+// phpcs:disable WordPress.WhiteSpace.PrecisionAlignment.Found
+
+// Quit.
+defined( 'ABSPATH' ) || exit;
+
+// Update plugin options.
+if ( ! empty( $_POST['statifyblacklist'] ) ) {
+	// Verify nonce.
+	check_admin_referer( 'statify-blacklist-settings' );
+
+	// Check user capabilities.
+	if ( ! current_user_can( 'manage_options' ) ) {
+		die( esc_html__( 'Are you sure you want to do this?', 'statify-blacklist' ) );
+	}
+
+	if ( ! empty( $_POST['cleanUp'] ) ) {
+		// CleanUp DB.
+		StatifyBlacklist_Admin::cleanup_database();
+	} else {
+		// Extract referer array.
+		if ( isset( $_POST['statifyblacklist']['referer']['blacklist'] ) ) {
+			$referer_str = sanitize_textarea_field( wp_unslash( $_POST['statifyblacklist']['referer']['blacklist'] ) );
+		}
+		if ( empty( trim( $referer_str ) ) ) {
+			$referer = array();
+		} else {
+			$referer = array_filter(
+				array_map(
+					function ( $a ) {
+						return trim( $a );
+					},
+					explode( "\r\n", $referer_str )
+				),
+				function ( $a ) {
+					return ! empty( $a );
+				}
+			);
+		}
+
+		// Extract target array.
+		if ( isset( $_POST['statifyblacklist']['target']['blacklist'] ) ) {
+			$target_str = sanitize_textarea_field( wp_unslash( $_POST['statifyblacklist']['target']['blacklist'] ) );
+		}
+		if ( empty( trim( $target_str ) ) ) {
+			$target = array();
+		} else {
+			$target = array_filter(
+				array_map(
+					function ( $a ) {
+						return trim( $a );
+					},
+					explode( "\r\n", str_replace( '\\\\', '\\', $target_str ) )
+				),
+				function ( $a ) {
+					return ! empty( $a );
+				}
+			);
+		}
+
+		// Extract IP array.
+		if ( isset( $_POST['statifyblacklist']['ip']['blacklist'] ) ) {
+			$ip_str = sanitize_textarea_field( wp_unslash( $_POST['statifyblacklist']['ip']['blacklist'] ) );
+		}
+		if ( empty( trim( $ip_str ) ) ) {
+			$ip = array();
+		} else {
+			$ip = array_filter(
+				array_map(
+					function ( $a ) {
+						return trim( $a );
+					},
+					explode( "\r\n", $ip_str )
+				),
+				function ( $a ) {
+					return ! empty( $a );
+				}
+			);
+		}
+
+		// TODO: Extract user agent array.
+		if ( isset( $_POST['statifyblacklist']['ua']['blacklist'] ) ) {
+			$ua_string = sanitize_textarea_field( wp_unslash( $_POST['statifyblacklist']['ua']['blacklist'] ) );
+		}
+		if ( empty( trim( $ua_string ) ) ) {
+			$ua = array();
+		} else {
+			$ua = array_filter(
+				array_map(
+					function ( $a ) {
+						return trim( $a );
+					},
+					explode( "\r\n", str_replace( '\\\\', '\\', $ua_string ) )
+				),
+				function ( $a ) {
+					return ! empty( $a );
+				}
+			);
+		}
+
+		// Update options (data will be sanitized).
+		$statifyblacklist_update_result = StatifyBlacklist_Admin::update_options(
+			array(
+				'referer' => array(
+					'active'    => isset( $_POST['statifyblacklist']['referer']['active'] )
+						? (int) $_POST['statifyblacklist']['referer']['active'] : 0,
+					'cron'      => isset( $_POST['statifyblacklist']['referer']['cron'] )
+						? (int) $_POST['statifyblacklist']['referer']['cron'] : 0,
+					'regexp'    => isset( $_POST['statifyblacklist']['referer']['regexp'] )
+						? (int) $_POST['statifyblacklist']['referer']['regexp'] : 0,
+					'blacklist' => array_flip( $referer ),
+				),
+				'target'  => array(
+					'active'    => isset( $_POST['statifyblacklist']['target']['active'] )
+						? (int) $_POST['statifyblacklist']['target']['active'] : 0,
+					'cron'      => isset( $_POST['statifyblacklist']['target']['cron'] )
+						? (int) $_POST['statifyblacklist']['target']['cron'] : 0,
+					'regexp'    => isset( $_POST['statifyblacklist']['target']['regexp'] )
+						? (int) $_POST['statifyblacklist']['target']['regexp'] : 0,
+					'blacklist' => array_flip( $target ),
+				),
+				'ip'      => array(
+					'active'    => isset( $_POST['statifyblacklist']['ip']['active'] )
+						? (int) $_POST['statifyblacklist']['ip']['active'] : 0,
+					'blacklist' => $ip,
+				),
+				'ua'      => array(
+					'active'    => isset( $_POST['statifyblacklist']['ua']['active'] )
+						? (int) $_POST['statifyblacklist']['ua']['active'] : 0,
+					'regexp'    => isset( $_POST['statifyblacklist']['ua']['regexp'] )
+						? (int) $_POST['statifyblacklist']['ua']['regexp'] : 0,
+					'blacklist' => $ua,
+				),
+				'version' => StatifyBlacklist::VERSION_MAIN,
+			)
+		);
+
+		// Generate messages.
+		if ( false !== $statifyblacklist_update_result ) {
+			$statifyblacklist_post_warning = array();
+			if ( ! empty( $statifyblacklist_update_result['referer']['diff'] ) ) {
+				$statifyblacklist_post_warning[] = __( 'Some URLs are invalid and have been sanitized.', 'statify-blacklist' );
+			}
+			if ( ! empty( $statifyblacklist_update_result['referer']['invalid'] ) ) {
+				$statifyblacklist_post_warning[] = __( 'Some regular expressions are invalid:', 'statify-blacklist' ) . '<br>' . implode( '<br>', $statifyblacklist_update_result['referer']['invalid'] );
+			}
+			if ( ! empty( $statifyblacklist_update_result['ip']['diff'] ) ) {
+				// translators: List of invalid IP addresses (comma separated).
+				$statifyblacklist_post_warning[] = sprintf( __( 'Some IPs are invalid: %s', 'statify-blacklist' ), implode( ', ', $statifyblacklist_update_result['ip']['diff'] ) );
+			}
+		} else {
+			$statifyblacklist_post_success = __( 'Settings updated successfully.', 'statify-blacklist' );
+		}
+	}
+}
+
+/*
+ * Disable some code style rules that are impractical for textarea content:
+ *
+ * phpcs:disable Squiz.PHP.EmbeddedPhp.ContentBeforeOpen
+ * phpcs:disable Squiz.PHP.EmbeddedPhp.ContentAfterEnd
+ */
+?>
+
+<div class="wrap">
+	<h1><?php esc_html_e( 'Statify Filter', 'statify-blacklist' ); ?></h1>
+	<?php
+	if ( is_plugin_inactive( 'statify/statify.php' ) ) {
+		print '<div class="notice notice-warning"><p>';
+		esc_html_e( 'Statify plugin is not active.', 'statify-blacklist' );
+		print '</p></div>';
+	}
+	if ( isset( $statifyblacklist_post_warning ) ) {
+		foreach ( $statifyblacklist_post_warning as $w ) {
+			print '<div class="notice notice-warning"><p>' .
+				wp_kses( $w, array( 'br' => array() ) ) .
+				'</p></div>';
+		}
+		print '<div class="notice notice-warning"><p>' . esc_html__( 'Settings have not been saved yet.', 'statify-blacklist' ) . '</p></div>';
+	}
+	if ( isset( $statifyblacklist_post_success ) ) {
+		print '<div class="notice notice-success"><p>' .
+			esc_html( $statifyblacklist_post_success ) .
+			'</p></div>';
+	}
+	?>
+	<form action="" method="post" id="statify-blacklist-settings">
+		<?php wp_nonce_field( 'statify-blacklist-settings' ); ?>
+
+		<h2><?php esc_html_e( 'Referer filter', 'statify-blacklist' ); ?></h2>
+
+		<table class="form-table">
+			<tbody>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_active_referer">
+						<?php esc_html_e( 'Activate live filter', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[referer][active]"
+						   id="statify-blacklist_active_referer"
+						   value="1" <?php checked( StatifyBlacklist::$options['referer']['active'], 1 ); ?>>
+					<p class="description">
+						<?php esc_html_e( 'Filter at time of tracking, before anything is stored', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_cron_referer">
+						<?php esc_html_e( 'CronJob execution', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[referer][cron]" id="statify-blacklist_cron_referer"
+						   value="1" <?php checked( StatifyBlacklist::$options['referer']['cron'], 1 ); ?>>
+					<p class="description"><?php esc_html_e( 'Periodically clean up database in background', 'statify-blacklist' ); ?></p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_referer_regexp"><?php esc_html_e( 'Matching method', 'statify-blacklist' ); ?></label>
+				</th>
+				<td>
+					<select name="statifyblacklist[referer][regexp]" id="statify-blacklist_referer_regexp">
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_NORMAL ); ?>" <?php selected( StatifyBlacklist::$options['referer']['regexp'], StatifyBlacklist::MODE_NORMAL ); ?>>
+							<?php esc_html_e( 'Domain', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_KEYWORD ); ?>" <?php selected( StatifyBlacklist::$options['referer']['regexp'], StatifyBlacklist::MODE_KEYWORD ); ?>>
+							<?php esc_html_e( 'Keyword', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX ); ?>" <?php selected( StatifyBlacklist::$options['referer']['regexp'], StatifyBlacklist::MODE_REGEX ); ?>>
+							<?php esc_html_e( 'RegEx case-sensitive', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX_CI ); ?>" <?php selected( StatifyBlacklist::$options['referer']['regexp'], StatifyBlacklist::MODE_REGEX_CI ); ?>>
+							<?php esc_html_e( 'RegEx case-insensitive', 'statify-blacklist' ); ?>
+						</option>
+					</select>
+
+					<p class="description">
+						<?php esc_html_e( 'Domain', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match given domain including subdomains', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'Keyword', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match every referer that contains one of the keywords', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'RegEx', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match referer by regular expression', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_referer"><?php esc_html_e( 'Referer filter', 'statify-blacklist' ); ?></label>
+				</th>
+				<td>
+					<textarea cols="40" rows="5" name="statifyblacklist[referer][blacklist]" id="statify-blacklist_referer"><?php
+					if ( empty( $statifyblacklist_update_result['referer'] ) ) {
+						print esc_html( implode( "\r\n", array_keys( StatifyBlacklist::$options['referer']['blacklist'] ) ) );
+					} else {
+						print esc_html( implode( "\r\n", array_keys( $statifyblacklist_update_result['referer']['sanitized'] ) ) );
+					}
+					?></textarea>
+					<p class="description">
+						<?php esc_html_e( 'Add one domain (without subdomains) each line, e.g. example.com', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			</tbody>
+		</table>
+
+		<h2><?php esc_html_e( 'Target filter', 'statify-blacklist' ); ?></h2>
+
+		<table class="form-table">
+			<tbody>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_active_target">
+						<?php esc_html_e( 'Activate live filter', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[target][active]"
+						   id="statify-blacklist_active_target"
+						   value="1" <?php checked( StatifyBlacklist::$options['target']['active'], 1 ); ?>>
+					<p class="description">
+						<?php esc_html_e( 'Filter at time of tracking, before anything is stored', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_cron_target">
+						<?php esc_html_e( 'CronJob execution', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[target][cron]" id="statify-blacklist_cron_target"
+						   value="1" <?php checked( StatifyBlacklist::$options['target']['cron'], 1 ); ?>>
+					<p class="description">
+						<?php esc_html_e( 'Clean database periodically in background', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_target_regexp">
+						<?php esc_html_e( 'Matching method', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<select name="statifyblacklist[target][regexp]" id="statify-blacklist_target_regexp">
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_NORMAL ); ?>" <?php selected( StatifyBlacklist::$options['target']['regexp'], StatifyBlacklist::MODE_NORMAL ); ?>>
+							<?php esc_html_e( 'Exact', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX ); ?>" <?php selected( StatifyBlacklist::$options['target']['regexp'], StatifyBlacklist::MODE_REGEX ); ?>>
+							<?php esc_html_e( 'RegEx case-sensitive', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX_CI ); ?>" <?php selected( StatifyBlacklist::$options['target']['regexp'], StatifyBlacklist::MODE_REGEX_CI ); ?>>
+							<?php esc_html_e( 'RegEx case-insensitive', 'statify-blacklist' ); ?>
+						</option>
+					</select>
+
+					<p class="description">
+						<?php esc_html_e( 'Exact', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match only given targets', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'RegEx', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match target by regular expression', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_target">
+						<?php esc_html_e( 'Target filter', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<textarea cols="40" rows="5" name="statifyblacklist[target][blacklist]" id="statify-blacklist_target"><?php
+					if ( empty( $statifyblacklist_update_result['target'] ) ) {
+						print esc_html( implode( "\r\n", array_keys( StatifyBlacklist::$options['target']['blacklist'] ) ) );
+					} else {
+						print esc_html( implode( "\r\n", array_keys( $statifyblacklist_update_result['target']['sanitized'] ) ) );
+					}
+					?></textarea>
+
+					<p class="description">
+						<?php esc_html_e( 'Add one target URL each line, e.g.', 'statify-blacklist' ); ?> /, /test/page/, /?page_id=123
+					</p>
+				</td>
+			</tr>
+			</tbody>
+		</table>
+
+		<h2><?php esc_html_e( 'IP filter', 'statify-blacklist' ); ?></h2>
+
+		<table class="form-table">
+			<tbody>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_active_ip">
+						<?php esc_html_e( 'Activate live filter', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[ip][active]" id="statify-blacklist_active_ip"
+						   value="1" <?php checked( StatifyBlacklist::$options['ip']['active'], 1 ); ?>>
+					<p class="description">
+						<?php esc_html_e( 'Filter at time of tracking, before anything is stored', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'Cron execution is not possible for IP filter, because IP addresses are not stored.', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_ip"><?php esc_html_e( 'IP filter', 'statify-blacklist' ); ?></label>:
+				</th>
+				<td>
+					<textarea cols="40" rows="5" name="statifyblacklist[ip][blacklist]" id="statify-blacklist_ip"><?php
+					if ( empty( $statifyblacklist_update_result['ip'] ) ) {
+						print esc_html( implode( "\r\n", StatifyBlacklist::$options['ip']['blacklist'] ) );
+					} else {
+						print esc_html( implode( "\r\n", $statifyblacklist_update_result['ip']['sanitized'] ) );
+					}
+					?></textarea>
+
+					<p class="description">
+						<?php esc_html_e( 'Add one IP address or range per line, e.g.', 'statify-blacklist' ); ?>
+						127.0.0.1, 192.168.123.0/24, 2001:db8:a0b:12f0::1/64
+					</p>
+				</td>
+			</tr>
+			</tbody>
+		</table>
+
+		<h2><?php esc_html_e( 'User agent filter', 'statify-blacklist' ); ?></h2>
+
+		<table class="form-table">
+			<tbody>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_active_ua">
+						<?php esc_html_e( 'Activate live filter', 'statify-blacklist' ); ?>
+					</label>
+				</th>
+				<td>
+					<input type="checkbox" name="statifyblacklist[ua][active]" id="statify-blacklist_active_ua"
+						   value="1" <?php checked( StatifyBlacklist::$options['ua']['active'], 1 ); ?>>
+					<p class="description">
+						<?php esc_html_e( 'Filter at time of tracking, before anything is stored', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'Cron execution is not possible for user agent filter, because the user agent is stored.', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_ua_regexp"><?php esc_html_e( 'Matching method', 'statify-blacklist' ); ?></label>
+				</th>
+				<td>
+					<select name="statifyblacklist[ua][regexp]" id="statify-blacklist_ua_regexp">
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_NORMAL ); ?>" <?php selected( StatifyBlacklist::$options['ua']['regexp'], StatifyBlacklist::MODE_NORMAL ); ?>>
+							<?php esc_html_e( 'Exact', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_KEYWORD ); ?>" <?php selected( StatifyBlacklist::$options['ua']['regexp'], StatifyBlacklist::MODE_KEYWORD ); ?>>
+							<?php esc_html_e( 'Keyword', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX ); ?>" <?php selected( StatifyBlacklist::$options['ua']['regexp'], StatifyBlacklist::MODE_REGEX ); ?>>
+							<?php esc_html_e( 'RegEx case-sensitive', 'statify-blacklist' ); ?>
+						</option>
+						<option value="<?php print esc_attr( StatifyBlacklist::MODE_REGEX_CI ); ?>" <?php selected( StatifyBlacklist::$options['ua']['regexp'], StatifyBlacklist::MODE_REGEX_CI ); ?>>
+							<?php esc_html_e( 'RegEx case-insensitive', 'statify-blacklist' ); ?>
+						</option>
+					</select>
+
+					<p class="description">
+						<?php esc_html_e( 'Exact', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match only given user agents', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'Keyword', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match every referer that contains one of the keywords', 'statify-blacklist' ); ?>
+						<br>
+						<?php esc_html_e( 'RegEx', 'statify-blacklist' ); ?> - <?php esc_html_e( 'Match user agent by regular expression', 'statify-blacklist' ); ?>
+					</p>
+				</td>
+			</tr>
+			<tr>
+				<th scope="row">
+					<label for="statify-blacklist_ua"><?php esc_html_e( 'User agent filter', 'statify-blacklist' ); ?></label>:
+				</th>
+				<td>
+					<textarea cols="40" rows="5" name="statifyblacklist[ua][blacklist]" id="statify-blacklist_ua"><?php
+					if ( empty( $statifyblacklist_update_result['ua'] ) ) {
+						print esc_html( implode( "\r\n", StatifyBlacklist::$options['ua']['blacklist'] ) );
+					} else {
+						print esc_html( implode( "\r\n", $statifyblacklist_update_result['ua']['sanitized'] ) );
+					}
+					?></textarea>
+
+					<p class="description">
+						<?php esc_html_e( 'Add one user agent string per line, e.g.', 'statify-blacklist' ); ?>
+						MyBot/1.23
+					</p>
+				</td>
+			</tr>
+			</tbody>
+		</table>
+
+		<p class="submit">
+			<input class="button-primary" type="submit" name="submit" value="<?php esc_html_e( 'Save Changes', 'statify-blacklist' ); ?>">
+			<hr>
+			<input class="button-secondary" type="submit" name="cleanUp"
+				   value="<?php esc_html_e( 'CleanUp Database', 'statify-blacklist' ); ?>"
+				   onclick="return confirm('Do you really want to apply filters to database? This cannot be undone.');">
+			<br>
+			<p class="description">
+				<?php esc_html_e( 'Applies referer and target filter (even if disabled) to data stored in database.', 'statify-blacklist' ); ?>
+				<em><?php esc_html_e( 'This cannot be undone!', 'statify-blacklist' ); ?></em>
+			</p>
+		</p>
+	</form>
+</div>

views/settings_page.php

@@ -1,131 +0,0 @@
-<?php
-
-/* Quit */
-defined( 'ABSPATH' ) OR exit;
-
-/* Update plugin options */
-if ( ! empty( $_POST['statifyblacklist'] ) ) {
-	/* Verify nonce */
-	check_admin_referer( 'statify-blacklist-settings' );
-
-	/* Check user capabilities */
-	if ( ! current_user_can( 'manage_options' ) ) {
-		die( _e( 'Are you sure you want to do this?' ) );
-	}
-
-	if ( ! empty( $_POST['cleanUp'] ) ) {
-		/* CleanUp DB */
-		StatifyBlacklist_Admin::cleanup_database();
-	} else {
-		/* Extract referer array */
-		if ( empty( trim( $_POST['statifyblacklist']['referer'] ) ) ) {
-			$referer = array();
-		} else {
-			$referer = explode( "\r\n", $_POST['statifyblacklist']['referer'] );
-		}
-
-		/* Update options (data will be sanitized) */
-		$statifyBlacklistUpdateResult = StatifyBlacklist_Admin::update_options(
-			array(
-				'active_referer' => (int) @$_POST['statifyblacklist']['active_referer'],
-				'cron_referer'   => (int) @$_POST['statifyblacklist']['cron_referer'],
-				'referer'        => array_flip( $referer ),
-				'referer_regexp' => (int) @$_POST['statifyblacklist']['referer_regexp']
-			)
-		);
-
-		/* Generate messages */
-		if ( $statifyBlacklistUpdateResult !== false ) {
-			$statifyBlacklistPostWarning = 'Some URLs are invalid and have been sanitized. Settings have not been saved yet.';
-		} else {
-			$statifyBlacklistPostSuccess = 'Settings updated successfully.';
-		}
-	}
-}
-?>
-
-<div class="wrap">
-	<h1><?php _e( 'Statify Blacklist', 'statify-blacklist' ) ?></h1>
-	<?php
-	if ( is_plugin_inactive( 'statify/statify.php' ) ) {
-		print '<div class="notice notice-warning"><p>';
-		esc_html_e( 'Statify plugin is not active.', 'statify-blacklist' );
-		print '</p></div>';
-	}
-	if ( isset( $statifyBlacklistPostWarning ) ) {
-		print '<div class="notice notice-warning"><p>';
-		esc_html_e( $statifyBlacklistPostWarning );
-		print '</p></div>';
-	}
-	if ( isset( $statifyBlacklistPostSuccess ) ) {
-		print '<div class="notice notice-success"><p>';
-		esc_html_e( $statifyBlacklistPostSuccess );
-		print '</p></div>';
-	}
-	?>
-	<form action="" method="post" id="statify-blacklist-settings">
-		<ul style="list-style: none;">
-			<li>
-				<label for="statify-blacklist_active_referer">
-					<input type="checkbox" name="statifyblacklist[active_referer]" id="statifyblacklist_active_referer"
-					       value="1" <?php checked( StatifyBlacklist::$_options['active_referer'], 1 ); ?> />
-					<?php esc_html_e( 'Activate referer blacklist', 'statify-blacklist' ); ?>
-				</label>
-			</li>
-			<li>
-				<label for="statify-blacklist_cron_referer">
-					<input type="checkbox" name="statifyblacklist[cron_referer]" id="statifyblacklist_cron_referer"
-					       value="1" <?php checked( StatifyBlacklist::$_options['cron_referer'], 1 ); ?> />
-					<?php esc_html_e( 'CronJob execution', 'statify-blacklist' ); ?>
-					<small>(<?php esc_html_e( 'Clean database periodically in background', 'statify-blacklist' ); ?>)</small>
-				</label>
-			</li>
-			<li>
-				<label for="statify-blacklist_referer_regexp">
-					<?php esc_html_e( 'Use regular expressions', 'statify-blacklist' ); ?>:
-					<br />
-					<select name="statifyblacklist[referer_regexp]" id="statifyblacklist_referer_regexp">
-						<option value="0" <?php selected( StatifyBlacklist::$_options['referer_regexp'], 0 ); ?>>
-							<?php esc_html_e( 'Disabled', 'statify-blacklist' ); ?>
-						</option>
-						<option value="1" <?php selected( StatifyBlacklist::$_options['referer_regexp'], 1 ); ?>>
-							<?php esc_html_e( 'Case-sensitive', 'statify-blacklist' ); ?>
-						</option>
-						<option value="2" <?php selected( StatifyBlacklist::$_options['referer_regexp'], 2 ); ?>>
-							<?php esc_html_e( 'Case-insensitive', 'statify-blacklist' ); ?>
-						</option>
-					</select>
-					<small>(<?php esc_html_e( 'Performance slower than standard domain filter. Recommended for cron or manual execition only.', 'statify-blacklist' ); ?>)</small>
-				</label>
-			</li>
-			<li>
-				<label for="statify-blacklist_referer">
-					<?php esc_html_e( 'Referer blacklist:', 'statify-blacklist' ); ?><br/>
-					<textarea cols="40" rows="5" name="statifyblacklist[referer]" id="statify-blacklist_referer"><?php
-						if ( isset( $statifyBlacklistUpdateResult ) && $statifyBlacklistUpdateResult !== false ) {
-							print esc_html( implode( "\r\n", array_keys( $statifyBlacklistUpdateResult ) ) );
-						} else {
-							print esc_html( implode( "\r\n", array_keys( StatifyBlacklist::$_options['referer'] ) ) );
-						}
-						?></textarea>
-					<br />
-					<small>
-						(<?php esc_html_e( 'Add one domain (without subdomains) each line, e.g. example.com', 'statify-blacklist' ); ?>
-						)
-					</small>
-				</label>
-			</li>
-		</ul>
-		<?php wp_nonce_field( 'statify-blacklist-settings' ); ?>
-
-		<p class="submit">
-			<input class="button-primary" type="submit" name="submit" value="<?php _e( 'Save Changes' ) ?>">
-			<hr />
-			<input class="button-secondary" type="submit" name="cleanUp"
-			       value="<?php esc_html_e( 'CleanUp Database', 'statify-blacklist' ) ?>"
-			       onclick="return confirm('Do you really want to apply filters to database? This cannot be undone.');">
-			<br />
-			<small><?php esc_html_e( 'Applies filter (even if disabled) to data stored in database. This cannot be undone!', 'statify-blacklist' ); ?></small>
-		</p>
-	</form>
-</div>