<?php

namespace Application;

use Nette\Utils\Neon;

/**
 * Module loader
 * Load all aplication modules
 *
 * @author Pecina Ondřej
 * @version 1.0
 */
class ModuleLoader extends \Nette\Object {

  /**
   *  All loaded modules
   *
   * @var array
   */
  static $modules = array();

  /**
   *  Path to module cache file
   *
   * @var string
   */
  private static $configFile = null;

  /**
   * @param string $appDir
   * @return string
   */
  private static function getConfigFile($appDir) {
    if (is_file($default = $appDir . "/modules.neon"))
      self::$configFile = $default;
    else if (is_file($dir = $appDir . "/config/modules.neon")) {
      self::$configFile = $dir;
    }
    return self::$configFile;
  }

  /**
   * @param string $appDir
   */
  private static function loadCache($appDir) {
    self::$modules = (array) Neon::decode(@file_get_contents(self::getConfigFile($appDir)));
  }

  /**
   * @param \Nette\Config\Configurator $configurator
   * @param \Nette\Loaders\RobotLoader $robotLoader
   */
  private static function createCache(\Nette\Config\Configurator $configurator, \Nette\Loaders\RobotLoader $robotLoader) {
    foreach ($robotLoader->getIndexedClasses() as $className => $class) {
      if (\Nette\Utils\Strings::match($className, '~AddOnModule~')) {
        self::$modules[] = $className;
      }
    }
    if (!empty(self::$modules[]))
      // make writable
      @chmod(self::$configFile, 0777);
      if (!@file_put_contents(self::$configFile, Neon::encode(self::$modules[], Neon::BLOCK)))
        throw new \Exception("Cant write module cache!");
  }

  /**
   * @param \Nette\Config\Configurator $configurator
   * @param \Nette\Loaders\RobotLoader $robotLoader
   * @param type $appDir
   */
  public static function register(\Nette\Config\Configurator $configurator, \Nette\Loaders\RobotLoader $robotLoader, $appDir) {
    // load cache
    self::loadCache($appDir);
    // create cache
    if (empty(self::$modules))
      self::createCache($configurator, $robotLoader);
    // registre modules
    foreach (self::$modules as $moduleClass) {
      $configurator->onCompile[] = function ($configurator, $compiler) {
        $instance = new $moduleClass;
        if (!($instance instanceof \Application\CompilerExtension\Base))
          throw new \Exception("Module must be instance of \Application\CompilerExtension\Base");
        if (!defined($moduleClass::moduleSlug))
          throw new \Exception("Module name must be declared, $moduleClass::moduleSlug");
        $compiler->addExtension($moduleClass::moduleSlug, new $moduleClass);
      };
    }
  }

}