<?php

/*
 * Copyright 2012 Facebook, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Include a CSS or JS static resource by name. This function records a
 * dependency for the current page, so when a response is generated it can be
 * included. You can call this method from any context, and it is recommended
 * you invoke it as close to the actual dependency as possible so that page
 * dependencies are minimized.
 *
 * For more information, see @{article:Adding New CSS and JS}.
 *
 * @param string Name of the celerity module to include. This is whatever you
 *               annotated as "@provides" in the file.
 * @return void
 *
 * @group celerity
 */
function require_celerity_resource($symbol) {
  $response = CelerityAPI::getStaticResourceResponse();
  $response->requireResource($symbol);
}


/**
 * Generate a node ID which is guaranteed to be unique for the current page,
 * even across Ajax requests. You should use this method to generate IDs for
 * nodes which require a uniqueness guarantee.
 *
 * @return string A string appropriate for use as an 'id' attribute on a DOM
 *                node. It is guaranteed to be unique for the current page, even
 *                if the current request is a subsequent Ajax request.
 *
 * @group celerity
 */
function celerity_generate_unique_node_id() {
  static $uniq = 0;
  $response = CelerityAPI::getStaticResourceResponse();
  $block = $response->getMetadataBlock();

  return 'UQ'.$block.'_'.($uniq++);
}


/**
 * Get the versioned URI for a raw resource, like an image.
 *
 * @param   string  Path to the raw image.
 * @return  string  Versioned path to the image, if one is available.
 *
 * @group celerity
 */
function celerity_get_resource_uri($resource) {
  $map = CelerityResourceMap::getInstance();

  $info = $map->lookupFileInformation($resource);
  if ($info) {
    return $info['uri'];
  } else {
    return $resource;
  }
}