<?php
global $LOADER_FILE_DIR;
$LOADER_FILE_DIR = dirname ( __FILE__ );

class ZirrorAPI_Loader {

  /**
   * Static function to resolve the qualified php filename to absolute path
   *
   * @global <String> $LOADER_FILE_DIR
   * @param <String> $qualifiedName
   * @return <String> Absolute File Name
   */
  static function resolveNameToPath($qualifiedName, $fileExtension = 'php') {

    global $LOADER_FILE_DIR;
    $allowedExtensions = array (
        'php',
        'js',
        'css',
        'less'
    );

    $file = '';
    if (! in_array ( $fileExtension, $allowedExtensions )) {
      return '';
    }
    // TO handle loading vtiger files
    if (strpos ( $qualifiedName, '~~' ) === 0) {
      $file = str_replace ( '~~', '', $qualifiedName );
      $file = $LOADER_FILE_DIR . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR . $file;
    } else if (strpos ( $qualifiedName, '~' ) === 0) {
      $file = str_replace ( '~', '', $qualifiedName );
      $file = $LOADER_FILE_DIR . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR . $file;
    } else {
      $file = str_replace ( '.', DIRECTORY_SEPARATOR, $qualifiedName ) . '.' . $fileExtension;
      $file = $LOADER_FILE_DIR . DIRECTORY_SEPARATOR . '..' . DIRECTORY_SEPARATOR . $file;
    }
    return $file;

  }

  /**
   * Function to get the class name of a given Component, of given Type, for a given Module
   *
   * @param <String> $componentType
   * @param <String> $componentName
   * @param <String> $moduleName
   * @return <String> Required Class Name
   * @throws AppException
   */
  public static function getComponentClassName($componentType, $componentName, $moduleName = 'Vtiger') {

    // Change component type from view to views, action to actions to navigate to the right path.
    $componentTypeDirectory = strtolower ( $componentType ) . 's';
    // Fall Back Directory & Fall Back Class
    $fallBackModuleDir = $fallBackModuleClassPath = 'Vtiger';
    // Intermediate Fall Back Directories & Classes, before relying on final fall back
    $firstFallBackModuleDir = $firstFallBackModuleClassPath = '';
    $secondFallBackDir = $secondFallBackClassPath = '';
    // Default module directory & class name
    $moduleDir = $moduleClassPath = $moduleName;
    // Change the Module directory & class, along with intermediate fall back directory and class, if module names has submodule as well
    if (strpos ( $moduleName, ':' ) > 0) {
      $moduleHierarchyParts = explode ( ':', $moduleName );
      $moduleDir = str_replace ( ':', '.', $moduleName );
      $moduleClassPath = str_replace ( ':', '_', $moduleName );
      $actualModule = $moduleHierarchyParts [count ( $moduleHierarchyParts ) - 1];
      $secondFallBackModuleDir = $secondFallBackModuleClassPath = $actualModule;
      if ($actualModule != 'Users') {
        $baseModule = $moduleHierarchyParts [0];
        if ($baseModule == 'Settings')
          $baseModule = 'Settings:Vtiger';
        $firstFallBackDir = str_replace ( ':', '.', $baseModule );
        $firstFallBackClassPath = str_replace ( ':', '_', $baseModule );
      }
    }
    // Build module specific file path and class name
    $moduleSpecificComponentFilePath = ZirrorAPI_Loader::resolveNameToPath ( 'modules.' . $moduleDir . '.' . $componentTypeDirectory . '.' . $componentName );
    $moduleSpecificComponentClassName = $moduleClassPath . '_' . $componentName . '_' . $componentType;
    if (file_exists ( $moduleSpecificComponentFilePath )) {
      return $moduleSpecificComponentClassName;
    }

    // Build first intermediate fall back file path and class name
    if (! empty ( $firstFallBackDir ) && ! empty ( $firstFallBackClassPath )) {
      $fallBackComponentFilePath = ZirrorAPI_Loader::resolveNameToPath ( 'modules.' . $firstFallBackDir . '.' . $componentTypeDirectory . '.' . $componentName );
      $fallBackComponentClassName = $firstFallBackClassPath . '_' . $componentName . '_' . $componentType;

      if (file_exists ( $fallBackComponentFilePath )) {
        return $fallBackComponentClassName;
      }
    }

    // Build intermediate fall back file path and class name
    if (! empty ( $secondFallBackModuleDir ) && ! empty ( $secondFallBackModuleClassPath )) {
      $fallBackComponentFilePath = ZirrorAPI_Loader::resolveNameToPath ( 'modules.' . $secondFallBackModuleDir . '.' . $componentTypeDirectory . '.' . $componentName );
      $fallBackComponentClassName = $secondFallBackModuleClassPath . '_' . $componentName . '_' . $componentType;

      if (file_exists ( $fallBackComponentFilePath )) {
        return $fallBackComponentClassName;
      }
    }

    // Build fall back file path and class name
    $fallBackComponentFilePath = ZirrorAPI_Loader::resolveNameToPath ( 'modules.' . $fallBackModuleDir . '.' . $componentTypeDirectory . '.' . $componentName );
    $fallBackComponentClassName = $fallBackModuleClassPath . '_' . $componentName . '_' . $componentType;
    if (file_exists ( $fallBackComponentFilePath )) {
      return $fallBackComponentClassName;
    }
    throw new AppException ( 'Handler not found.' );

  }

}