#431 initial commit for MONSTRA 4

monstra/Filter.php

@@ -0,0 +1,120 @@
+<?php
+
+/**
+ * This file is part of the Monstra.
+ *
+ * (c) Romanenko Sergey / Awilum <awilum@msn.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+class Filter
+{
+    /**
+     * Filters
+     *
+     * @var array
+     * @access protected
+     */
+    protected static $filters = [];
+
+    /**
+     * Protected constructor since this is a static class.
+     *
+     * @access protected
+     */
+    protected function __construct()
+    {
+        // Nothing here
+    }
+
+    /**
+     * Apply filters
+     *
+     *  <code>
+     *      Filter::apply('content', $content);
+     *  </code>
+     *
+     * @access  public
+     * @param  string $filter_name The name of the filter hook.
+     * @param  mixed  $value       The value on which the filters hooked.
+     * @return mixed
+     */
+    public static function apply($filter_name, $value)
+    {
+        // Redefine arguments
+        $filter_name = (string) $filter_name;
+
+        $args = array_slice(func_get_args(), 2);
+
+        if (! isset(static::$filters[$filter_name])) {
+            return $value;
+        }
+
+        foreach (static::$filters[$filter_name] as $priority => $functions) {
+            if (! is_null($functions)) {
+                foreach ($functions as $function) {
+                    $all_args = array_merge(array($value), $args);
+                    $function_name = $function['function'];
+                    $accepted_args = $function['accepted_args'];
+                    if ($accepted_args == 1) {
+                        $the_args = array($value);
+                    } elseif ($accepted_args > 1) {
+                        $the_args = array_slice($all_args, 0, $accepted_args);
+                    } elseif ($accepted_args == 0) {
+                        $the_args = null;
+                    } else {
+                        $the_args = $all_args;
+                    }
+                    $value = call_user_func_array($function_name, $the_args);
+                }
+            }
+        }
+
+        return $value;
+    }
+
+    /**
+     * Add filter
+     *
+     *  <code>
+     *      Filter::add('content', 'replacer');
+     *
+     *      function replacer($content) {
+     *          return preg_replace(array('/\[b\](.*?)\[\/b\]/ms'), array('<strong>\1</strong>'), $content);
+     *      }
+     *  </code>
+     *
+     * @access  public
+     * @param  string  $filter_name     The name of the filter to hook the $function_to_add to.
+     * @param  string  $function_to_add The name of the function to be called when the filter is applied.
+     * @param  integer $priority        Function to add priority - default is 10.
+     * @param  integer $accepted_args   The number of arguments the function accept default is 1.
+     * @return boolean
+     */
+    public static function add($filter_name, $function_to_add, $priority = 10, $accepted_args = 1)
+    {
+        // Redefine arguments
+        $filter_name     = (string) $filter_name;
+        $function_to_add = $function_to_add;
+        $priority        = (int) $priority;
+        $accepted_args   = (int) $accepted_args;
+
+        // Check that we don't already have the same filter at the same priority. Thanks to WP :)
+        if (isset(static::$filters[$filter_name]["$priority"])) {
+            foreach (static::$filters[$filter_name]["$priority"] as $filter) {
+                if ($filter['function'] == $function_to_add) {
+                    return true;
+                }
+            }
+        }
+
+        static::$filters[$filter_name]["$priority"][] = array('function' => $function_to_add, 'accepted_args' => $accepted_args);
+
+        // Sort
+        ksort(static::$filters[$filter_name]["$priority"]);
+
+        return true;
+    }
+}