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Drupal example source code file (imagecache.module)

This example Drupal source code file (imagecache.module) is included in the DevDaily.com "Drupal Source Code Warehouse" project. The intent of this project is to help you "Learn Drupal by Example".

PHP - Drupal tags/keywords

action, array, directory, element, file, function, if, image, imagecache, null, path, php, preset, return

The imagecache.module Drupal example source code

<?php
// $Id: imagecache.module,v 1.112.2.5 2009/08/19 20:59:07 drewish Exp $

/**
 * @file
 * Dynamic image resizer and image cacher.
 *
 * ImageCache allows you to setup presets for image processing.
 * If an ImageCache derivative doesn't exist the web server's
 * rewrite rules will pass the request to Drupal which in turn
 * hands it off to imagecache to dynamically generate the file.
 *
 * To view a derivative image you request a special url containing
 * 'imagecache/<presetname>/path/to/file.ext.
 *
 * Presets can be managed at http://example.com/admin/build/imagecache.
 *
 * To view a derivative image you request a special url containing
 * 'imagecache/<presetname>/path/to/file.ext.
 *
 * If you had a preset names 'thumbnail' and you wanted to see the
 * thumbnail version of  http://example.com/files/path/to/myimage.jpg you
 * would use http://example.com/files/imagecache/thumbnail/path/to/myimage.jpg
 *
 * ImageCache provides formatters for CCK Imagefields and is leveraged by several
 * other modules. ImageCache also relies heavily on ImageAPI for it's image processing.
 * If there are errors with actual image processing look to ImageAPI first.
 *
 * @todo: add watermarking capabilities.
 *
 */

/**
 * Imagecache preset storage constant for user-defined presets in the DB.
 */
define('IMAGECACHE_STORAGE_NORMAL', 0);

/**
 * Imagecache preset storage constant for module-defined presets in code.
 */
define('IMAGECACHE_STORAGE_DEFAULT', 1);

/**
 * Imagecache preset storage constant for user-defined presets that override
 * module-defined presets.
 */
define('IMAGECACHE_STORAGE_OVERRIDE', 2);

/*********************************************************************************************
 * Drupal Hooks
 *********************************************************************************************/

/**
 * Implementation of hook_perm().
 */
function imagecache_perm() {
  $perms =  array('administer imagecache', 'flush imagecache');
  foreach (imagecache_presets() as $preset) {
    $perms[] =  'view imagecache '. $preset['presetname'];
  }
  return $perms;
}

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

  // standard imagecache callback.
  $items[file_directory_path() .'/imagecache'] = array(
    'page callback' => 'imagecache_cache',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK
  );
  // private downloads imagecache callback
  $items['system/files/imagecache'] = array(
    'page callback' => 'imagecache_cache_private',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK
  );

  return $items;
}

/**
 * Clear imagecache presets cache on admin/build/modules form.
 */
function imagecache_form_system_modules_alter(&$form, $form_state) {
  imagecache_presets(TRUE);
}

/**
 * Implementation of hook_theme().
 */
function imagecache_theme() {
  $theme = array(
    'imagecache' => array(
      'arguments' => array(
        'namespace' => NULL,
        'path' => NULL,
        'alt' => NULL,
        'title' => NULL,
    )),
    'imagecache_imagelink' => array(
      'arguments' => array(
        'namespace' => NULL,
        'path' => NULL,
        'alt' => NULL,
        'title' => NULL,
        'attributes' => array(),
    )),
    'imagecache_resize' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_scale' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_scale_and_crop' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_deprecated_scale' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_crop' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_desaturate' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_rotate' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
    'imagecache_sharpen' => array(
      'file' => 'imagecache_actions.inc',
      'arguments' => array('element' => NULL),
    ),
  );

  foreach (imagecache_presets() as $preset) {
    $theme['imagecache_formatter_'. $preset['presetname'] .'_default'] = array(
      'arguments' => array('element' => NULL),
      'function' => 'theme_imagecache_formatter_default',
    );
    $theme['imagecache_formatter_'. $preset['presetname'] .'_linked'] = array(
      'arguments' => array('element' => NULL),
      'function' => 'theme_imagecache_formatter_linked',
    );
    $theme['imagecache_formatter_'. $preset['presetname'] .'_imagelink'] = array(
      'arguments' => array('element' => NULL),
      'function' => 'theme_imagecache_formatter_imagelink',
    );
    $theme['imagecache_formatter_'. $preset['presetname'] .'_path'] = array(
      'arguments' => array('element' => NULL),
      'function' => 'theme_imagecache_formatter_path',
    );
    $theme['imagecache_formatter_'. $preset['presetname'] .'_url'] = array(
      'arguments' => array('element' => NULL),
      'function' => 'theme_imagecache_formatter_url',
    );
  }

  return $theme;

}

/**
 * Implementation of hook_imagecache_actions.
 *
 * @return array
 *   An array of information on the actions implemented by a module. The array
 *   contains a sub-array for each action node type, with the machine-readable
 *   action name as the key. Each sub-array has up to 3 attributes. Possible
 *   attributes:
 *
 *     "name": the human-readable name of the action. Required.
 *     "description": a brief description of the action. Required.
 *     "file": the name of the include file the action can be found
 *             in relative to the implementing module's path.
 */
function imagecache_imagecache_actions() {
  $actions = array(
    'imagecache_resize' => array(
      'name' => 'Resize',
      'description' => 'Resize an image to an exact set of dimensions, ignoring aspect ratio.',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_scale' => array(
      'name' => 'Scale',
      'description' => 'Resize an image maintaining the original aspect-ratio (only one value necessary).',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_deprecated_scale' => array(
      'name' => 'Deprecated Scale',
      'description' => 'Precursor to Scale and Crop. Has inside and outside dimension support. This action will be removed in ImageCache 2.1).',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_scale_and_crop' => array(
      'name' => 'Scale And Crop',
      'description' => 'Resize an image while maintaining aspect ratio, then crop it to the specified dimensions.',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_crop' => array(
      'name' => 'Crop',
      'description' => 'Crop an image to the rectangle specified by the given offsets and dimensions.',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_desaturate' => array(
      'name' => 'Desaturate',
      'description' => 'Convert an image to grey scale.',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_rotate' => array(
      'name' => 'Rotate',
      'description' => 'Rotate an image.',
      'file' => 'imagecache_actions.inc',
    ),
    'imagecache_sharpen' => array(
      'name' => 'Sharpen',
      'description' => 'Sharpen an image using unsharp masking.',
      'file' => 'imagecache_actions.inc',
    ),
  );

  return $actions;
}

/**
 * Pull in actions exposed by other modules using hook_imagecache_actions().
 *
 * @param $reset
 *   Boolean flag indicating whether the cached data should be
 *   wiped and recalculated.
 *
 * @return
 *   An array of actions to be used when transforming images.
 */
function imagecache_action_definitions($reset = FALSE) {
  static $actions;
  if (!isset($actions) || $reset) {
    if (!$reset && ($cache = cache_get('imagecache_actions')) && !empty($cache->data)) {
      $actions = $cache->data;
    }
    else {
      foreach (module_implements('imagecache_actions') as $module) {
        foreach (module_invoke($module, 'imagecache_actions') as $key => $action) {
          $action['module'] = $module;
          if (!empty($action['file'])) {
            $action['file'] = drupal_get_path('module', $action['module']) .'/'. $action['file'];
          }
          $actions[$key] = $action;
        };
      }
      uasort($actions, '_imagecache_definitions_sort');
      cache_set('imagecache_actions', $actions);
    }
  }
  return $actions;
}

function _imagecache_definitions_sort($a, $b) {
  $a = $a['name'];
  $b = $b['name'];
  if ($a == $b) {
    return 0;
  }
  return ($a < $b) ? -1 : 1;
}

function imagecache_action_definition($action) {
  static $definition_cache;
  if (!isset($definition_cache[$action])) {
    $definitions = imagecache_action_definitions();
    $definition = (isset($definitions[$action])) ? $definitions[$action] : array();

    if (isset($definition['file'])) {
      require_once($definition['file']);
    }
    $definition_cache[$action] = $definition;
  }
  return $definition_cache[$action];
}

/**
 * Return a URL that points to the location of a derivative of the
 * original image transformed with the given preset.
 *
 * Special care is taken to make this work with the possible combinations of
 * Clean URLs and public/private downloads. For example, when Clean URLs are not
 * available an URL with query should be returned, like
 * http://example.com/?q=files/imagecache/foo.jpg, so that imagecache is able
 * intercept the request for this file.
 *
 * This code is very similar to the Drupal core function file_create_url(), but
 * handles the case of Clean URLs and public downloads differently however.
 *
 * @param $presetname
 * @param $filepath
 *   String specifying the path to the image file.
 * @param $bypass_browser_cache
 *   A Boolean indicating that the URL for the image should be distinct so that
 *   the visitors browser will not be able to use a previously cached version.
 *   This is
 */
function imagecache_create_url($presetname, $filepath, $bypass_browser_cache = FALSE) {
  $path = _imagecache_strip_file_directory($filepath);
  if (module_exists('transliteration')) {
    $path = transliteration_get($path);
  }

  $args = array('absolute' => TRUE, 'query' => empty($bypass_browser_cache) ? NULL : time());
  switch (variable_get('file_downloads', FILE_DOWNLOADS_PUBLIC)) {
    case FILE_DOWNLOADS_PUBLIC:
      return url($GLOBALS['base_url'] . '/' . file_directory_path() .'/imagecache/'. $presetname .'/'. $path, $args);
    case FILE_DOWNLOADS_PRIVATE:
      return url('system/files/imagecache/'. $presetname .'/'. $path, $args);
  }
}

/**
 * Return a file system location that points to the location of a derivative
 * of the original image at @p $path, transformed with the given @p $preset.
 * Keep in mind that the image might not yet exist and won't be created.
 */
function imagecache_create_path($presetname, $path) {
  $path = _imagecache_strip_file_directory($path);
  return file_create_path() .'/imagecache/'. $presetname .'/'. $path;
}

/**
 * Remove a possible leading file directory path from the given path.
 */
function _imagecache_strip_file_directory($path) {
  $dirpath = file_directory_path();
  $dirlen = strlen($dirpath);
  if (substr($path, 0, $dirlen + 1) == $dirpath .'/') {
    $path = substr($path, $dirlen + 1);
  }
  return $path;
}


/**
 * callback for handling public files imagecache requests.
 */
function imagecache_cache() {
  $args = func_get_args();
  $preset = check_plain(array_shift($args));
  $path = implode('/', $args);
  _imagecache_cache($preset, $path);
}

/**
 * callback for handling private files imagecache requests
 */
function imagecache_cache_private() {
  $args = func_get_args();
  $preset = check_plain(array_shift($args));
  $source = implode('/', $args);

  if (user_access('view imagecache '. $preset) && !in_array(-1, module_invoke_all('file_download', $source))) {
    _imagecache_cache($preset, $source);
  }
  else {
    // if there is a 403 image, display it.
    $accesspath = file_create_path('imagecache/'. $preset .'.403.png');
    if (is_file($accesspath)) {
      imagecache_transfer($accesspath);
      exit;
    }
    header('HTTP/1.0 403 Forbidden');
    exit;
  }
}

/**
 * handle request validation and responses to imagecache requests.
 */
function _imagecache_cache($presetname, $path) {
  if (!$preset = imagecache_preset_by_name($presetname)) {
    // Send a 404 if we don't know of a preset.
    header("HTTP/1.0 404 Not Found");
    exit;
  }

  // umm yeah deliver it early if it is there. especially useful
  // to prevent lock files from being created when delivering private files.
  $dst = imagecache_create_path($preset['presetname'], $path);
  if (is_file($dst)) {
    imagecache_transfer($dst);
  }

  // preserve path for watchdog.
  $src = $path;

  // Check if the path to the file exists.
  if (!is_file($src) && !is_file($src = file_create_path($src))) {
    watchdog('imagecache', '404: Unable to find %image ', array('%image' => $src), WATCHDOG_ERROR);
    header("HTTP/1.0 404 Not Found");
    exit;
  };

  // Bail if the requested file isn't an image you can't request .php files
  // etc...
  if (!getimagesize($src)) {
    watchdog('imagecache', '403: File is not an image %image ', array('%image' => $src), WATCHDOG_ERROR);
    header('HTTP/1.0 403 Forbidden');
    exit;
  }

  $lockfile = file_directory_temp() .'/'. $preset['presetname'] . basename($src);
  if (file_exists($lockfile)) {
    watchdog('imagecache', 'ImageCache already generating: %dst, Lock file: %tmp.', array('%dst' => $dst, '%tmp' => $lockfile), WATCHDOG_NOTICE);
    // 307 Temporary Redirect, to myself. Lets hope the image is done next time around.
    header('Location: '. request_uri(), TRUE, 307);
    exit;
  }
  touch($lockfile);
  // register the shtdown function to clean up lock files. by the time shutdown
  // functions are being called the cwd has changed from document root, to
  // server root so absolute paths must be used for files in shutdown functions.
  register_shutdown_function('file_delete', realpath($lockfile));

  // check if deriv exists... (file was created between apaches request handler and reaching this code)
  // otherwise try to create the derivative.
  if (file_exists($dst) || imagecache_build_derivative($preset['actions'], $src, $dst)) {
    imagecache_transfer($dst);
  }
  // Generate an error if image could not generate.
  watchdog('imagecache', 'Failed generating an image from %image using imagecache preset %preset.', array('%image' => $path, '%preset' => $preset['presetname']), WATCHDOG_ERROR);
  header("HTTP/1.0 500 Internal Server Error");
  exit;
}

/**
 * Apply an action to an image.
 *
 * @param $action
 *   Action array
 * @param $image
 *   Image object
 * @return
 *   Boolean, TRUE indicating success and FALSE failure.
 */
function _imagecache_apply_action($action, $image) {
  $actions = imagecache_action_definitions();

  if ($definition = imagecache_action_definition($action['action'])) {
    $function = $action['action'] .'_image';
    if (function_exists($function)) {
      return $function($image, $action['data']);
    }
  }
  // skip undefined actions.. module probably got uninstalled or disabled.
  watchdog('imagecache', 'non-existant action %action', array('%action' => $action['action']), WATCHDOG_NOTICE);
  return TRUE;
}

/**
 * Helper function to transfer files from imagecache.
 *
 * Determines MIME type and sets a last modified header.
 *
 * @param $path
 *   String containing the path to file to be transferred.
 * @return
 *   This function does not return. It calls exit().
 */

function imagecache_transfer($path) {
  $size = getimagesize($path);
  $headers = array('Content-Type: '. mime_header_encode($size['mime']));

  if ($fileinfo = stat($path)) {
    $headers[] = 'Content-Length: '. $fileinfo[7];
    $headers[] = 'Expires: ' . gmdate('D, d M Y H:i:s', time() + 1209600) .' GMT';
    $headers[] = 'Cache-Control: max-age=1209600, private, must-revalidate';
    _imagecache_cache_set_cache_headers($fileinfo, $headers);
  }
  file_transfer($path, $headers);
  exit;
}

/**
 * Set file headers that handle "If-Modified-Since" correctly for the
 * given fileinfo.
 *
 * Note that this function may return or may call exit().
 *
 * Most code has been taken from drupal_page_cache_header().
 *
 * @param $fileinfo
 *   Array returned by stat().
 * @param
 *   Array of existing headers.
 * @return
 *   Nothing but beware that this function may not return.
 */
function _imagecache_cache_set_cache_headers($fileinfo, &$headers) {
  // Set default values:
  $last_modified = gmdate('D, d M Y H:i:s', $fileinfo[9]) .' GMT';
  $etag = '"'. md5($last_modified) .'"';

  // See if the client has provided the required HTTP headers:
  $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE'])
                        ? stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE'])
                        : FALSE;
  $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH'])
                    ? stripslashes($_SERVER['HTTP_IF_NONE_MATCH'])
                    : FALSE;

  if ($if_modified_since && $if_none_match
      && $if_none_match == $etag // etag must match
      && $if_modified_since == $last_modified) { // if-modified-since must match
    header('HTTP/1.1 304 Not Modified');
    // All 304 responses must send an etag if the 200 response
    // for the same object contained an etag
    header('Etag: '. $etag);
    // We must also set Last-Modified again, so that we overwrite Drupal's
    // default Last-Modified header with the right one
    header('Last-Modified: '. $last_modified);
    exit;
  }

  // Send appropriate response:
  $headers[] = 'Last-Modified: '. $last_modified;
  $headers[] = 'ETag: '. $etag;
}

/**
 * Create a new image based on an image preset.
 *
 * @param $preset
 *   An image preset array.
 * @param $source
 *   Path of the source file.
 * @param $destination
 *   Path of the destination file.
 * @return
 *   TRUE if an image derivative is generated, FALSE if no image
 *  derivative is generated. NULL if the derivative is being generated.
 */
function imagecache_build_derivative($actions, $src, $dst) {
  // get the folder for the final location of this preset...
  $dir = dirname($dst);

  // Build the destination folder tree if it doesn't already exists.
  if (!file_check_directory($dir, FILE_CREATE_DIRECTORY) && !mkdir($dir, 0775, TRUE)) {
    watchdog('imagecache', 'Failed to create imagecache directory: %dir', array('%dir' => $dir), WATCHDOG_ERROR);
    return FALSE;
  }

  // Simply copy the file if there are no actions.
  if (empty($actions)) {
    return file_copy($src, $dst, FILE_EXISTS_REPLACE);
  }

  if (!$image = imageapi_image_open($src)) {
    return FALSE;
  }

  if (file_exists($dst)) {
    watchdog('imagecache', 'Cached image file %dst already exists but is being regenerated. There may be an issue with your rewrite configuration.', array('%dst' => $dst), WATCHDOG_WARNING);
  }

  foreach ($actions as $action) {
    if (!empty($action['data'])) {
      // Make sure the width and height are computed first so they can be used
      // in relative x/yoffsets like 'center' or 'bottom'.
      if (isset($action['data']['width'])) {
        $action['data']['width']   = _imagecache_percent_filter($action['data']['width'], $image->info['width']);
      }
      if (isset($action['data']['height'])) {
        $action['data']['height']  = _imagecache_percent_filter($action['data']['height'], $image->info['height']);
      }
      if (isset($action['data']['xoffset'])) {
        $action['data']['xoffset'] = _imagecache_keyword_filter($action['data']['xoffset'], $image->info['width'], $action['data']['width']);
      }
      if (isset($action['data']['yoffset'])) {
        $action['data']['yoffset'] = _imagecache_keyword_filter($action['data']['yoffset'], $image->info['height'], $action['data']['height']);
      }
    }
    if (!_imagecache_apply_action($action, $image)) {
      watchdog('imagecache', 'action(id:%id): %action failed for %src', array('%id' => $action['actionid'], '%action' => $action['action'], '%src' => $src), WATCHDOG_ERROR);
      return FALSE;
    }
  }

  if (!imageapi_image_close($image, $dst)) {
    watchdog('imagecache', 'There was an error saving the new image file %dst.', array('%dst' => $dst), WATCHDOG_ERROR);
    return FALSE;
  }

  return TRUE;
}

/**
 * Implementation of hook_user().
 */
function imagecache_user($op, &$edit, &$account, $category = NULL) {
  // Flush cached old user picture.
  if ($op == 'update' && !empty($account->picture)) {
    imagecache_image_flush($account->picture);
  }
}

/**
 * Implementation of filefield.module's hook_file_delete().
 *
 * Remove derivative images after the originals are deleted by filefield.
 */
function imagecache_file_delete($file) {
  imagecache_image_flush($file->filepath);
}

/**
 * Implementation of hook_field_formatter_info().
 *
 * imagecache formatters are named as $presetname_$style
 * $style is used to determine how the preset should be rendered.
 * If you are implementing custom imagecache formatters please treat _ as
 * reserved.
 *
 * @todo: move the linking functionality up to imagefield and clean up the default image
 * integration.
 */
function imagecache_field_formatter_info() {
  $formatters = array();
  foreach (imagecache_presets() as $preset) {
    $formatters[$preset['presetname'] .'_default'] = array(
      'label' => t('@preset image', array('@preset' => $preset['presetname'])),
      'field types' => array('image', 'filefield'),
    );
    $formatters[$preset['presetname'] .'_linked'] = array(
      'label' => t('@preset image linked to node', array('@preset' => $preset['presetname'])),
      'field types' => array('image', 'filefield'),
    );
    $formatters[$preset['presetname'] .'_imagelink'] = array(
      'label' => t('@preset image linked to image', array('@preset' => $preset['presetname'])),
      'field types' => array('image', 'filefield'),
    );
    $formatters[$preset['presetname'] .'_path'] = array(
      'label' => t('@preset file path', array('@preset' => $preset['presetname'])),
      'field types' => array('image', 'filefield'),
    );
    $formatters[$preset['presetname'] .'_url'] = array(
      'label' => t('@preset URL', array('@preset' => $preset['presetname'])),
      'field types' => array('image', 'filefield'),
    );
  }
  return $formatters;
}

function theme_imagecache_formatter_default($element) {
  // Inside a view $element may contain NULL data. In that case, just return.
  if (empty($element['#item']['fid'])) {
    return '';
  }

  // Extract the preset name from the formatter name.
  $presetname = substr($element['#formatter'], 0, strrpos($element['#formatter'], '_'));
  $style = 'linked';
  $style = 'default';

  $item = $element['#item'];
  $item['data']['alt'] = isset($item['data']['alt']) ? $item['data']['alt'] : '';
  $item['data']['title'] = isset($item['data']['title']) ? $item['data']['title'] : NULL;

  $class = "imagecache imagecache-$presetname imagecache-$style imagecache-{$element['#formatter']}";
  return theme('imagecache', $presetname, $item['filepath'], $item['data']['alt'], $item['data']['title'], array('class' => $class));
}

function theme_imagecache_formatter_linked($element) {
  // Inside a view $element may contain NULL data. In that case, just return.
  if (empty($element['#item']['fid'])) {
    return '';
  }

  // Extract the preset name from the formatter name.
  $presetname = substr($element['#formatter'], 0, strrpos($element['#formatter'], '_'));
  $style = 'linked';

  $item = $element['#item'];
  $item['data']['alt'] = isset($item['data']['alt']) ? $item['data']['alt'] : '';
  $item['data']['title'] = isset($item['data']['title']) ? $item['data']['title'] : NULL;

  $imagetag = theme('imagecache', $presetname, $item['filepath'], $item['data']['alt'], $item['data']['title']);
  $path = empty($item['nid']) ? '' : 'node/'. $item['nid'];
  $class = "imagecache imagecache-$presetname imagecache-$style imagecache-{$element['#formatter']}";
  return l($imagetag, $path, array('attributes' => array('class' => $class), 'html' => TRUE));
}

function theme_imagecache_formatter_imagelink($element) {
  // Inside a view $element may contain NULL data. In that case, just return.
  if (empty($element['#item']['fid'])) {
    return '';
  }

  // Extract the preset name from the formatter name.
  $presetname = substr($element['#formatter'], 0, strrpos($element['#formatter'], '_'));
  $style = 'imagelink';

  $item = $element['#item'];
  $item['data']['alt'] = isset($item['data']['alt']) ? $item['data']['alt'] : '';
  $item['data']['title'] = isset($item['data']['title']) ? $item['data']['title'] : NULL;

  $imagetag = theme('imagecache', $presetname, $item['filepath'], $item['data']['alt'], $item['data']['title']);
  $path = file_create_url($item['filepath']);
  $class = "imagecache imagecache-$presetname imagecache-$style imagecache-{$element['#formatter']}";
  return l($imagetag, $path, array('attributes' => array('class' => $class), 'html' => TRUE));
}

function theme_imagecache_formatter_path($element) {
  // Inside a view $element may contain NULL data. In that case, just return.
  if (empty($element['#item']['fid'])) {
    return '';
  }

  // Extract the preset name from the formatter name.
  $presetname = substr($element['#formatter'], 0, strrpos($element['#formatter'], '_'));

  return imagecache_create_path($presetname, $element['#item']['filepath']);
}

function theme_imagecache_formatter_url($element) {
  // Inside a view $element may contain NULL data. In that case, just return.
  if (empty($element['#item']['fid'])) {
    return '';
  }

  // Extract the preset name from the formatter name.
  $presetname = substr($element['#formatter'], 0, strrpos($element['#formatter'], '_'));

  return imagecache_create_url($presetname, $element['#item']['filepath']);
}

/**
 * Accept a percentage and return it in pixels.
 */
function _imagecache_percent_filter($value, $current_pixels) {
  if (strpos($value, '%') !== FALSE) {
    $value = str_replace('%', '', $value) * 0.01 * $current_pixels;
  }
  return $value;
}

/**
 * Accept a keyword (center, top, left, etc) and return it as an offset in pixels.
 */
function _imagecache_keyword_filter($value, $current_pixels, $new_pixels) {
  switch ($value) {
    case 'top':
    case 'left':
      $value = 0;
      break;
    case 'bottom':
    case 'right':
      $value = $current_pixels - $new_pixels;
      break;
    case 'center':
      $value = $current_pixels/2 - $new_pixels/2;
      break;
  }
  return $value;
}

/**
 * Recursively delete all files and folders in the specified filepath, then
 * delete the containing folder.
 *
 * Note that this only deletes visible files with write permission.
 *
 * @param string $path
 *   A filepath relative to file_directory_path.
 */
function _imagecache_recursive_delete($path) {
  if (is_file($path) || is_link($path)) {
    unlink($path);
  }
  elseif (is_dir($path)) {
    $d = dir($path);
    while (($entry = $d->read()) !== FALSE) {
      if ($entry == '.' || $entry == '..') continue;
      $entry_path = $path .'/'. $entry;
      _imagecache_recursive_delete($entry_path);
    }
    $d->close();
    rmdir($path);
  }
  else {
    watchdog('imagecache', 'Unknown file type(%path) stat: %stat ',
              array('%path' => $path,  '%stat' => print_r(stat($path),1)), WATCHDOG_ERROR);
  }

}

/**
 * Create and image tag for an imagecache derivative
 *
 * @param $presetname
 *   String with the name of the preset used to generate the derivative image.
 * @param $path
 *   String path to the original image you wish to create a derivative image
 *   tag for.
 * @param $alt
 *   Optional string with alternate text for the img element.
 * @param $title
 *   Optional string with title for the img element.
 * @param $attributes
 *   Optional drupal_attributes() array. If $attributes is an array then the
 *   default imagecache classes will not be set automatically, you must do this
 *   manually.
 * @param $getsize
 *   If set to TRUE, the image's dimension are fetched and added as width/height
 *   attributes.
 * @return
 *   HTML img element string.
 */
function theme_imagecache($presetname, $path, $alt = '', $title = '', $attributes = NULL, $getsize = TRUE) {
  // Check is_null() so people can intentionally pass an empty array of
  // to override the defaults completely.
  if (is_null($attributes)) {
    $attributes = array('class' => 'imagecache imagecache-'. $presetname);
  }
  if ($getsize && ($image = image_get_info(imagecache_create_path($presetname, $path)))) {
    $attributes['width'] = $image['width'];
    $attributes['height'] = $image['height'];
  }

  $attributes = drupal_attributes($attributes);
  $imagecache_url = imagecache_create_url($presetname, $path);
  return '<img src="'. $imagecache_url .'" alt="'. check_plain($alt) .'" title="'. check_plain($title) .'" '. $attributes .' />';
}

/**
 * Create a link the original image that wraps the derivative image.
 *
 * @param $presetname
 *   String with the name of the preset used to generate the derivative image.
 * @param $path
 *   String path to the original image you wish to create a derivative image
 *   tag for.
 * @param $alt
 *   Optional string with alternate text for the img element.
 * @param $title
 *   Optional string with title for the img element.
 * @param attributes
 *   Optional drupal_attributes() array for the link.
 * @return
 *   An HTML string.
 */
function theme_imagecache_imagelink($presetname, $path, $alt = '', $title = '', $attributes = NULL) {
  $image = theme('imagecache', $presetname, $path, $alt, $title);
  $original_image_url = file_create_url($path);
  return l($image, $original_image_url, array('absolute' => FALSE, 'html' => TRUE));
}

/**
 *  ImageCache 2.x API
 *
 *  The API for imagecache has changed.  The 2.x API returns more structured
 *  data, has shorter function names, and implements more aggressive metadata
 *  caching.
 *
 */

/**
 * Get an array of all presets and their settings.
 *
 * @param reset
 *   if set to TRUE it will clear the preset cache
 *
 * @return
 *   array of presets array( $preset_id => array('presetid' => integer, 'presetname' => string))
 */
function imagecache_presets($reset = FALSE) {
  static $presets = array();

  // Clear  caches if $reset is TRUE;
  if ($reset) {
    $presets = array();
    cache_clear_all('imagecache:presets', 'cache');

    // Clear the content.module cache (refreshes the list of formatters provided by imagefield.module).
    if (module_exists('content')) {
      content_clear_type_cache();
    }
  }
  // Return presets if the array is populated.
  if (!empty($presets)) {
    return $presets;
  }

  // Grab from cache or build the array. To ensure that the Drupal 5 upgrade
  // path works, we also check whether the presets list is an array.
  if (($cache = cache_get('imagecache:presets', 'cache')) && is_array($cache->data)) {
    $presets = $cache->data;
  }
  else {
    $normal_presets = array();

    $result = db_query('SELECT * FROM {imagecache_preset} ORDER BY presetname');
    while ($preset = db_fetch_array($result)) {
      $presets[$preset['presetid']] = $preset;
      $presets[$preset['presetid']]['actions'] = imagecache_preset_actions($preset);
      $presets[$preset['presetid']]['storage'] = IMAGECACHE_STORAGE_NORMAL;

      // Collect normal preset names so we can skip defaults and mark overrides accordingly
      $normal_presets[$preset['presetname']] = $preset['presetid'];
    }

    // Collect default presets and allow modules to modify them before they
    // are cached.
    $default_presets = module_invoke_all('imagecache_default_presets');
    drupal_alter('imagecache_default_presets', $default_presets);

    // Add in default presets if they don't conflict with any normal presets.
    // Mark normal presets that take the same preset namespace as overrides.
    foreach ($default_presets as $preset) {
      if (!empty($preset['presetname'])) {
        if (!isset($normal_presets[$preset['presetname']])) {
          $preset['storage'] = IMAGECACHE_STORAGE_DEFAULT;
          // Use a string preset identifier
          $preset['presetid'] = $preset['presetname'];
          $presets[$preset['presetname']] = $preset;
        }
        else {
          $presetid = $normal_presets[$preset['presetname']];
          $presets[$presetid]['storage'] = IMAGECACHE_STORAGE_OVERRIDE;
        }
      }
    }

    cache_set('imagecache:presets', $presets);
  }
  return $presets;
}

/**
 * Load a preset by preset_id.
 *
 * @param preset_id
 *   The numeric id of a preset.
 *
 * @return
 *   preset array( 'presetname' => string, 'presetid' => integet)
 *   empty array if preset_id is an invalid preset
 */
function imagecache_preset($preset_id, $reset = FALSE) {
  $presets = imagecache_presets($reset);
  return (isset($presets[$preset_id])) ? $presets[$preset_id] : array();
}

/**
 * Load a preset by name.
 *
 * @param preset_name
 *
 * @return
 *   preset array( 'presetname' => string, 'presetid' => integer)
 *   empty array if preset_name is an invalid preset
 */

function imagecache_preset_by_name($preset_name) {
  static $presets_by_name = array();
  if (!$presets_by_name &&  $presets = imagecache_presets()) {
    foreach ($presets as $preset) {
      $presets_by_name[$preset['presetname']] = $preset;
    }
  }
  return (isset($presets_by_name[$preset_name])) ? $presets_by_name[$preset_name] : array();
}

/**
 * Save an ImageCache preset.
 *
 * @param preset
 *   an imagecache preset array.
 * @return
 *   a preset array.  In the case of a new preset, 'presetid' will be populated.
 */
function imagecache_preset_save($preset) {
  // @todo: CRUD level validation?
  if (isset($preset['presetid']) && is_numeric($preset['presetid'])) {
    drupal_write_record('imagecache_preset', $preset, 'presetid');
  }
  else {
    drupal_write_record('imagecache_preset', $preset);
  }

  // Reset presets cache.
  imagecache_preset_flush($preset);
  imagecache_presets(TRUE);

  // Rebuild Theme Registry
  drupal_rebuild_theme_registry();

  return $preset;
}

function imagecache_preset_delete($preset) {
  imagecache_preset_flush($preset);
  db_query('DELETE FROM {imagecache_action} where presetid = %d', $preset['presetid']);
  db_query('DELETE FROM {imagecache_preset} where presetid = %d', $preset['presetid']);
  imagecache_presets(TRUE);
  return TRUE;
}

function imagecache_preset_actions($preset, $reset = FALSE) {
  static $actions_cache = array();

  if ($reset || empty($actions_cache[$preset['presetid']])) {
    $result = db_query('SELECT * FROM {imagecache_action} where presetid = %d order by weight', $preset['presetid']);
    while ($row = db_fetch_array($result)) {
      $row['data'] = unserialize($row['data']);
      $actions_cache[$preset['presetid']][] = $row;
    }
  }

  return isset($actions_cache[$preset['presetid']]) ? $actions_cache[$preset['presetid']] : array();
}

/**
 * Flush cached media for a preset.
 *
 * @param preset
 *   an imagecache preset array.
 */
function imagecache_preset_flush($preset) {
  if (user_access('flush imagecache')) {
    $presetdir = realpath(file_directory_path() .'/imagecache/'. $preset['presetname']);
    if (is_dir($presetdir)) {
      _imagecache_recursive_delete($presetdir);
    }
  }
}

/**
 * Clear cached versions of a specific file in all presets.
 * @param $path
 *   The Drupal file path to the original image.
 */
function imagecache_image_flush($path) {
  foreach (imagecache_presets() as $preset) {
    file_delete(imagecache_create_path($preset['presetname'], $path));
  }
}

function imagecache_action($actionid) {
  static $actions;

  if (!isset($actions[$actionid])) {
    $action = array();

    $result = db_query('SELECT * FROM {imagecache_action} WHERE actionid=%d', $actionid);
    if ($row = db_fetch_array($result)) {
      $action = $row;
      $action['data'] = unserialize($action['data']);

      $definition = imagecache_action_definition($action['action']);
      $action = array_merge($definition, $action);
      $actions[$actionid] = $action;
    }
  }
  return $actions[$actionid];
}

function imagecache_action_load($actionid) {
  return imagecache_action($actionid, TRUE);
}

function imagecache_action_save($action) {
  $definition = imagecache_action_definition($action['action']);
  $action = array_merge($definition, $action);

  // Some actions don't have data. Make an empty one to prevent SQL errors.
  if (!isset($action['data'])) {
    $action['data'] = array();
  }

  if (!empty($action['actionid'])) {
    drupal_write_record('imagecache_action', $action, 'actionid');
  }
  else {
    drupal_write_record('imagecache_action', $action);
  }
  $preset = imagecache_preset($action['presetid']);
  imagecache_preset_flush($preset);
  imagecache_presets(TRUE);
  return $action;
}

function imagecache_action_delete($action) {
  db_query('DELETE FROM {imagecache_action} WHERE actionid=%d', $action['actionid']);
  $preset = imagecache_preset($action['presetid']);
  imagecache_preset_flush($preset);
  imagecache_presets(TRUE);
}

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