<?php
class Hook {
	static private $hooks = array();
	
	static function register($hook) {
		self::$hooks[] = $hook;
	}
	

	/**
	 * Function fire - Calls ("fires") a hook
	 * 
	 * @todo Documentation for this function needs to be reviewed. It may not be accurate. 
	 * 
	 * @param $function It's the name of the function.
	 * @param $argument It's the argument (Or set of arguments?) to be.
	 * @param $ret mixed holds the result of the function call.
	 * 
	 */
	static function fire($function, $argument, &$ret) {
		foreach (self::$hooks as $hook) {
			$callback = $hook."_".$function;
			if (function_exists($callback)) {
				$callback($argument, $ret);
			}
		}
	}
	
	static function init() {
		$base_hooks_dir = ROOT . "/hooks" ;
		if (is_dir($base_hooks_dir)) {
			$handle = opendir($base_hooks_dir);
			while ($file = readdir($handle)) {
				if (is_file("$base_hooks_dir/$file") && substr($file, -4) == '.php') {
					include_once "$base_hooks_dir/$file";
				}
			}
			closedir($handle);
		}
		
		foreach ( Plugins::instance()->getActive() as $plugin ){
			/* @var $plugin Plugin  */
			$plugin_hooks_dir = $plugin->getHooksPath();
			if (is_dir($plugin_hooks_dir)) {
				$handle = opendir($plugin_hooks_dir);
				while ($file = readdir($handle)) {
					if (is_file("$plugin_hooks_dir/$file") && substr($file, -4) == '.php') {
						include_once "$plugin_hooks_dir/$file";
					}
				}
				$plugin->getSystemName() ;
				closedir($handle);
			}
		}
	}
	
	/**
	 * Allow to call hooks with dynamic parameters
	 */
	static function invoke($function) { // Hook with dynamic arguments.
		$args = func_get_args ();
		unset ( $args [0] ); // Remove $function from arguments.
		foreach ( self::$hooks as $hook ) {
			$callback = $hook . "_" . $function;
			if (function_exists ( $callback )) {
				call_user_func_array ( $callback, $args );
			}
		}
	}
}