ting_covers.module

<?php

/**
 * @file ting_covers.module
 * Provide functionality and page callbacks for retrieving covers for Ting objects and collections
 */

define('SERVICE_ADDI', 0);
define('SERVICE_MOREINFO', 1);
define('TING_COVERS_CACHE_LIFETIME', 86400);

// Load Field module hooks.
module_load_include('inc', 'ting_covers', 'ting_covers.field');

/**
 * Implementation of hook_menu().
 */
function ting_covers_menu() {
  $items = array();

  $items['ting/covers'] = array(
    'title' => 'Retreives cover for Ting objects',
    'page callback' => 'ting_covers_objects',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'ting_covers.pages.inc',
  );

  $items['admin/config/ting/covers'] = array(
    'title' => 'Covers',
    'description' => 'Configure how covers are handled.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ting_covers_admin_settings_form'),
    'access arguments' => array('administer site configuration'),
    'file' => 'ting_covers.admin.inc',
  );

  $items['admin/config/ting/covers/setttings'] = array(
    'title' => 'Settings',
    'description' => 'Configure how covers are handled.',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );

  $items['admin/config/ting/covers/addi'] = array(
    'title' => 'ADDI service',
    'description' => 'Configure integration with the ADDI service.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ting_covers_admin_addi_settings_form'),
    'access arguments' => array('administer site configuration'),
    'file' => 'ting_covers.admin.inc',
    'type' => MENU_LOCAL_TASK,
  );

  return $items;
}

/**
 * Implementation of hook_theme().
 */
function ting_covers_theme() {
  return array(
    'ting_object_cover' => array(
      'render element' => 'elements',
      'file' => 'ting_covers.theme.inc',
    ),
  );
}

/**
 * Implementation of hook_cron().
 */
function ting_covers_cron() {
  _ting_covers_delete_old_files($_SERVER['REQUEST_TIME'] - variable_get('ting_covers_cache_lifetime', TING_COVERS_CACHE_LIFETIME));
}

/**
 * Implementation of hook_cache_clear().
 */
function ting_covers_flush_caches() {
  _ting_covers_delete_old_files($_SERVER['REQUEST_TIME'] - variable_get('ting_covers_cache_lifetime', TING_COVERS_CACHE_LIFETIME));
}

/**
 * Implements hook_ding_install_tasks().
 */
function ting_covers_ding_install_tasks() {
  module_load_include('inc', 'ting_covers', 'ting_covers.admin');
  return array(
    'ting_covers_admin_addi_settings_form' => array(
      'display_name' => st('ADDI service settings'),
      'type' => 'form',
      'file' => drupal_get_path('module', 'ting_covers') . '/ting_covers.admin.inc',
    ),
  );
}

/**
 * Template preprocessor.
 */
function ting_covers_preprocess_ting_object(&$variables) {
  /*
   * Add the image style as a class, allowing templates to react on the size.
   */
  if (isset($variables['elements']['ting_cover'][0])) {
    $variables['classes_array'][] = drupal_html_class('imagestyle-' . $variables['elements']['ting_cover'][0]['#image_style']);
  }
}

/**
 * Delete ting covers files.
 *
 * @param int $time Timestamp where older files will be deleted.
 * 	Obmit or set to NULL to delete all files.
 */
function _ting_covers_delete_old_files($time = NULL) {
  //Collect potential locations of cover folders
  $files_dir = file_default_scheme() . '://';
  $image_dirs = array($files_dir);

  $styles_dir = $files_dir . 'styles';
  foreach (scandir($styles_dir) as $style_dir) {
    $style_dir = $styles_dir . DIRECTORY_SEPARATOR . $style_dir . DIRECTORY_SEPARATOR . 'public';
    if (is_dir($style_dir)) {
      $image_dirs[] = $style_dir;
    }
  }

  //Collect cover files
  $cover_files = array();
  foreach ($image_dirs as $uri) {
    $ting_covers_dir = $uri . DIRECTORY_SEPARATOR . 'ting' . DIRECTORY_SEPARATOR . 'covers';
    if (is_dir($ting_covers_dir)) {
      $cover_files = array_merge($cover_files, _ting_covers_get_files($ting_covers_dir));
    }
  }

  //Delete obsolete files
  foreach ($cover_files as $file) {
    if (!$time || (filemtime($file) < $time)) {
      file_unmanaged_delete($file);
    }
  }
}

/**
 * Retrieve all files under a path recursively
 * @param string $files_path Path or URI
 * @return array An array of file paths or URIs
 */
function _ting_covers_get_files($files_path) {
  $files = array();

  foreach (scandir($files_path) as $path) {
    $file_path = $files_path . DIRECTORY_SEPARATOR . $path;
    if (is_dir($file_path)) {
      if (!in_array($path, array('.', '..'))) {
        $files = array_merge($files, _ting_covers_get_files($file_path));
      }
    }
    else {
      $files[] = $file_path;
    }
  }

  return $files;
}

/**
 * Return the path to the cover of the object.
 */
function ting_covers_object_path($object_id) {
  return file_default_scheme() . '://ting/covers/object/' . md5($object_id) . '.jpg';
}