commit 4005f936cdd3e5504f712fef840d3d663d51fbd7
Author: Stefan Kalscheuer <stefan@stklcode.de>
Date:   Sun Aug 14 13:23:27 2016 +0200

    Initial commit. Extracted from former pull request on Statify project

diff --git a/inc/statifyblacklist.class.php b/inc/statifyblacklist.class.php
new file mode 100644
index 0000000..8049bd6
--- /dev/null
+++ b/inc/statifyblacklist.class.php
@@ -0,0 +1,120 @@
+<?php
+
+/* Quit */
+defined('ABSPATH') OR exit;
+
+/**
+ * Statify Blacklist
+ *
+ * @since 1.0.0
+ */
+class StatifyBlacklist
+{
+  /**
+   * Plugin options
+   *
+   * @since   1.0.0
+   */
+  public static $_options;
+
+  public static $multisite;
+
+  /**
+   * Class self initialize
+   *
+   * @since   1.0.0
+   */
+  public static function instance()
+  {
+    new self();
+  }
+
+  /**
+   * Class constructor
+   *
+   * @since   1.0.0
+   */
+  public function __construct()
+  {
+    /* Skip on autosave or AJAX */
+    if ( (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) OR (defined('DOING_AJAX') && DOING_AJAX) ) {
+      return;
+    }
+
+    /* Plugin options */
+    self::update_options();
+
+    self::$multisite = (is_multisite() && array_key_exists(STATIFYBLACKLIST_BASE, (array)get_site_option('active_sitewide_plugins')));
+
+    /* Add Filter to statify hook */
+    add_filter('statify_skip_tracking', array('StatifyBlacklist', 'apply_blacklist_filter'));
+
+    /* Admin only filters */
+    if ( is_admin() ) {
+      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()) {
+        register_deactivation_hook(__FILE__, array('StatifyBlacklist_Admin', 'single_site_deactivate'));
+        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   1.0.0
+   */
+  public static function update_options($options = null) {
+    if (isset($options)) {
+      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', $options);
+    }
+
+    self::$_options = wp_parse_args(
+      get_option('statify-blacklist'),
+      array(
+        'active_referer' => 0,
+        'referer'        => ''
+      )
+    );
+  }
+
+  /**
+   * Apply the blacklist filter if active
+   *
+   * @return  TRUE if referer matches blacklist.
+   *
+   * @since   1.0.0
+   */
+  public static function apply_blacklist_filter() {
+    /* Skip if blacklist is inactive */
+    if (self::$_options['active_referer'] != 1) {
+      return false;
+    }
+
+    /* Extract relevant domain parts */
+    $referer = strtolower( ( isset($_SERVER['HTTP_REFERER']) ? parse_url($_SERVER['HTTP_REFERER'], PHP_URL_HOST) : '' ) );
+    $referer = explode('.', $referer);
+    if( count($referer) >1 )
+      $referer = implode('.', array_slice($referer, -2));
+    else
+      $referer = implode('.', $referer);
+
+    /* Get blacklist */
+    $blacklist = explode("\r\n", self::$_options['referer']);
+
+    /* Check blacklist */
+    return in_array($referer, $blacklist);
+  }
+}
diff --git a/inc/statifyblacklist_admin.class.php b/inc/statifyblacklist_admin.class.php
new file mode 100644
index 0000000..0076687
--- /dev/null
+++ b/inc/statifyblacklist_admin.class.php
@@ -0,0 +1,54 @@
+<?php
+
+class StatifyBlacklist_Admin extends StatifyBlacklist
+{
+  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;
+  }
+}
\ No newline at end of file
diff --git a/inc/statifyblacklist_system.class.php b/inc/statifyblacklist_system.class.php
new file mode 100644
index 0000000..c4fe7b3
--- /dev/null
+++ b/inc/statifyblacklist_system.class.php
@@ -0,0 +1,80 @@
+<?php
+
+/* Quit */
+defined('ABSPATH') OR exit;
+
+/**
+ * Statify 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.
+   */
+  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()
+        );
+      }
+
+      restore_current_blog();
+    } else {
+      add_option(
+        'statify-blacklist',
+        array()
+      );
+    }
+  }
+
+  /**
+   * Plugin deactivation actions
+   *
+   * @since   1.0.0
+   */
+
+  public static function deactivate()
+  {
+  }
+
+  /**
+   * 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( $old );
+    }
+
+    delete_option('statify-blacklist');
+  }
+}
\ No newline at end of file
diff --git a/statifyblacklist.php b/statifyblacklist.php
new file mode 100644
index 0000000..d69d387
--- /dev/null
+++ b/statifyblacklist.php
@@ -0,0 +1,74 @@
+<?php
+/*
+Plugin Name: Statify Blacklist
+Description: Extension for the statify plugin to add a customizable blacklists.
+Text Domain: statify-blacklist
+Domain Path: /lang
+Author:      stklcode
+Author URI:  https://stklcode.de
+Plugin URI:  https://wordpress.org/plugins/statifyRefererBlacklist
+License:     GPLv3 or later
+Version:     1.0.0
+*/
+
+/* Quit */
+defined('ABSPATH') OR exit;
+
+/*  Constants */
+define('STATIFYBLACKLIST_FILE', __FILE__);
+define('STATIFYBLACKLIST_DIR', dirname(__FILE__));
+define('STATIFYBLACKLIST_BASE', plugin_basename(__FILE__));
+
+/* System Hooks */
+add_action(
+  'plugins_loaded',
+  array(
+    'StatifyBlacklist',
+    'instance'
+  )
+);
+
+register_activation_hook(
+  STATIFYBLACKLIST_FILE,
+  array(
+    'StatifyBlacklist_System',
+    'install'
+  )
+);
+
+register_deactivation_hook(
+  STATIFYBLACKLIST_FILE,
+  array(
+    'StatifyBlacklist_System',
+    'deactivate'
+  )
+);
+
+register_uninstall_hook(
+  STATIFYBLACKLIST_FILE,
+  array(
+    'StatifyBlacklist_System',
+    'uninstall'
+  )
+);
+
+/* Autoload */
+spl_autoload_register('statifyBlacklist_autoload');
+
+function statifyBlacklist_autoload($class) {
+  $plugin_classes = array(
+    'StatifyBlacklist',
+    'StatifyBlacklist_Admin',
+    'StatifyBlacklist_System'
+  );
+
+  if ( in_array($class, $plugin_classes) ) {
+    require_once(
+    sprintf(
+      '%s/inc/%s.class.php',
+      STATIFYBLACKLIST_DIR,
+      strtolower($class)
+    )
+    );
+  }
+}
diff --git a/views/settings_page.php b/views/settings_page.php
new file mode 100644
index 0000000..add40f8
--- /dev/null
+++ b/views/settings_page.php
@@ -0,0 +1,37 @@
+<?php
+
+/* Update plugin options */
+if ( ! empty($_POST['statifyblacklist']) ) {
+    StatifyBlacklist::update_options(
+      array(
+        'active_referer' => (int)@$_POST['statifyblacklist']['active_referer'],
+        'referer'        => (string)@$_POST['statifyblacklist']['referer']
+      )
+    );
+}
+
+?>
+
+<div class="wrap">
+    <h1><?php _e( 'Statify Blacklist', 'statify-blacklist') ?></h1>
+    <form action="" method="post" id="statify-blacklist-settings">
+        <ul style="list-style: none;">
+            <li>
+                <label for="statify-blacklist_active_referer">
+                    <input type="checkbox" name="statifyblacklist[active_referer]" id="statifyblacklist_active_referer" value="1" <?php checked(StatifyBlacklist::$_options['active_referer'], 1); ?> />
+                    <?php esc_html_e('Activate referer blacklist', 'statify-blacklist'); ?>
+                </label>
+            </li>
+            <li>
+                <label for="statify-blacklist_referer">
+                    <?php  esc_html_e('Referer blacklist:', 'statify-blacklist'); ?><br />
+                    <textarea cols="40" rows="5" name="statifyblacklist[referer]" id="statify-blacklist_referer"><?php print 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') ?>"></p>
+    </form>
+</div>