<?php

  class mw_env_helpers extends mw_env{

    public $helpers;

    public function init_helpers(){
      $this->helpers = false;
      $helpers_files = array();
      if(($plugins = $this->plugins()) !== false){
        foreach($plugins as $plugin_name => $plugin){
          $helpers_path = $this->path("mw_dir")."plugins/".$plugin_name."/app/helpers/";
          if(
               $plugin["installed"]
            && $plugin["enabled"]
            && file_exists($helpers_path)
            && is_dir($helpers_path)
          ){
            if($dh = opendir($helpers_path)){
              while(($file = readdir($dh)) !== false){
                if(
                     substr($file, 0, 1) != "."
                  && !is_dir($helpers_path.$file)
                  && strcmp(substr($file, -4), ".php") == 0
                  && !isset($helpers_files[$file])
                ) $helpers_files[$file] = $helpers_path;
              }
              closedir($dh);
            }
            else return false;
          }
        }
        $helpers_path = $this->path("mw_dir")."app/helpers/";
        if(
             file_exists($helpers_path)
          && is_dir($helpers_path)
        ){
          if($dh = opendir($helpers_path)){
            while(($file = readdir($dh)) !== false){
              if(
                   substr($file, 0, 1) != "."
                && !is_dir($helpers_path.$file)
                && strcmp(substr($file, -4), ".php") == 0
                && !isset($helpers_files[$file])
              ) $helpers_files[$file] = $helpers_path;
            }
            closedir($dh);
          }
          else return false;
        }
      }
      $this->helpers = array();
      foreach($helpers_files as $file => $helpers_path){
        $this->helpers[substr($file, 0, -4)] = array("file" => $helpers_path.$file);
      }
      return true;
    }

    public function helper($helper_name){
      if(!isset($this->helpers)) $this->init_helpers();
      if($this->helpers === false || !isset($this->helpers[$helper_name])) return false;
      if(!isset($this->helpers[$helper_name]["file"])) return false;
      if($this->init_helper($helper_name)) return $this->helpers[$helper_name]["impl"];
      return false;
    }

    public function init_helper($helper_name){
      if(!isset($this->helpers[$helper_name]["impl"])){
        if(!class_exists($helper_name)){
          if(
                !isset($this->helpers[$helper_name]["file"])
            ||  !$this->helpers[$helper_name]["file"]
            ||  !file_exists($this->helpers[$helper_name]["file"])
          ) return false;
          require_once $this->helpers[$helper_name]["file"];
          if(!class_exists($helper_name)) return false;
        }
        $this->helpers[$helper_name]["impl"] = new $helper_name();
        $this->helpers[$helper_name]["impl"]->set_env($this);
        return true;
      }
      if($this->helpers[$helper_name]["impl"] === false) return false;
      return true;
    }

  }

  // -------------------------------------------------------------------------------------------
  //                                                                             class mw_helper
  //

  abstract class mw_helper{

    public $env;

    public function set_env(&$env){
      $this->env = &$env;
    }

    public function env(){
      return $this->env;
    }

  }