<?php

/**

 * @file

 * Defines a "managed_file" Form API field and a "file" field for Field module.

 */

// Load all Field module hooks for File.

require_once DRUPAL_ROOT . '/modules/file/file.field.inc';

/**

 * Implements hook_help().

 */

function file_help($path, $arg) {

  switch ($path) {

    case 'admin/help#file':

      $output = '';

      $output .= '<h3>' . t('About') . '</h3>';

      $output .= '<p>' . t('The File module defines a <em>File</em> field type for the Field module, which lets you manage and validate uploaded files attached to content on your site (see the <a href="@field-help">Field module help page</a> for more information about fields). For more information, see the online handbook entry for <a href="@file">File module</a>.', array('@field-help' => url('admin/help/field'), '@file' => 'http://drupal.org/documentation/modules/file')) . '</p>';

      $output .= '<h3>' . t('Uses') . '</h3>';

      $output .= '<dl>';

      $output .= '<dt>' . t('Attaching files to content') . '</dt>';

      $output .= '<dd>' . t('The File module allows users to attach files to content (e.g., PDF files, spreadsheets, etc.), when a <em>File</em> field is added to a given content type using the <a href="@fieldui-help">Field UI module</a>. You can add validation options to your File field, such as specifying a maximum file size and allowed file extensions.', array('@fieldui-help' => url('admin/help/field_ui'))) . '</dd>';

      $output .= '<dt>' . t('Managing attachment display') . '</dt>';

      $output .= '<dd>' . t('When you attach a file to content, you can specify whether it is <em>listed</em> or not. Listed files are displayed automatically in a section at the bottom of your content; non-listed files are available for embedding in your content, but are not included in the list at the bottom.') . '</dd>';

      $output .= '<dt>' . t('Managing file locations') . '</dt>';

      $output .= '<dd>' . t("When you create a File field, you can specify a directory where the files will be stored, which can be within either the <em>public</em> or <em>private</em> files directory. Files in the public directory can be accessed directly through the web server; when public files are listed, direct links to the files are used, and anyone who knows a file's URL can download the file. Files in the private directory are not accessible directly through the web server; when private files are listed, the links are Drupal path requests. This adds to server load and download time, since Drupal must start up and resolve the path for each file download request, but allows for access restrictions.") . '</dd>';

      $output .= '</dl>';

      return $output;

  }

}

/**

 * Implements hook_menu().

 */

function file_menu() {

  $items = array();

  $items['file/ajax'] = array(

    'page callback' => 'file_ajax_upload',

    'delivery callback' => 'ajax_deliver',

    'access arguments' => array('access content'),

    'theme callback' => 'ajax_base_page_theme',

    'type' => MENU_CALLBACK,

  );

  $items['file/progress'] = array(

    'page callback' => 'file_ajax_progress',

    'access arguments' => array('access content'),

    'theme callback' => 'ajax_base_page_theme',

    'type' => MENU_CALLBACK,

  );

  return $items;

}

/**

 * Implements hook_element_info().

 *

 * The managed file element may be used anywhere in Drupal.

 */

function file_element_info() {

  $file_path = drupal_get_path('module', 'file');

  $types['managed_file'] = array(

    '#input' => TRUE,

    '#process' => array('file_managed_file_process'),

    '#value_callback' => 'file_managed_file_value',

    '#element_validate' => array('file_managed_file_validate'),

    '#pre_render' => array('file_managed_file_pre_render'),

    '#theme' => 'file_managed_file',

    '#theme_wrappers' => array('form_element'),

    '#progress_indicator' => 'throbber',

    '#progress_message' => NULL,

    '#upload_validators' => array(),

    '#upload_location' => NULL,

    '#size' => 22,

    '#extended' => FALSE,

    '#attached' => array(

      'css' => array($file_path . '/file.css'),

      'js' => array($file_path . '/file.js'),

    ),

  );

  return $types;

}

/**

 * Implements hook_theme().

 */

function file_theme() {

  return array(

    // file.module.

    'file_link' => array(

      'variables' => array('file' => NULL, 'icon_directory' => NULL),

    ),

    'file_icon' => array(

      'variables' => array('file' => NULL, 'icon_directory' => NULL, 'alt' => ''),

    ),

    'file_managed_file' => array(

      'render element' => 'element',

    ),

    // file.field.inc.

    'file_widget' => array(

      'render element' => 'element',

    ),

    'file_widget_multiple' => array(

      'render element' => 'element',

    ),

    'file_formatter_table' => array(

      'variables' => array('items' => NULL),

    ),

    'file_upload_help' => array(

      'variables' => array('description' => NULL, 'upload_validators' => NULL),

    ),

  );

}

/**

 * Implements hook_file_download().

 *

 * This function takes an extra parameter $field_type so that it may

 * be re-used by other File-like modules, such as Image.

 */

function file_file_download($uri, $field_type = 'file') {

  global $user;

  // Get the file record based on the URI. If not in the database just return.

  $files = file_load_multiple(array(), array('uri' => $uri));

  if (count($files)) {

    foreach ($files as $item) {

      // Since some database servers sometimes use a case-insensitive comparison

      // by default, double check that the filename is an exact match.

      if ($item->uri === $uri) {

        $file = $item;

        break;

      }

    }

  }

  if (!isset($file)) {

    return;

  }

  // Find out which (if any) fields of this type contain the file.

  $references = file_get_file_references($file, NULL, FIELD_LOAD_CURRENT, $field_type);

  // Stop processing if there are no references in order to avoid returning

  // headers for files controlled by other modules. Make an exception for

  // temporary files where the host entity has not yet been saved (for example,

  // an image preview on a node/add form) in which case, allow download by the

  // file's owner. For anonymous file owners, only the browser session that

  // uploaded the file should be granted access.

  if (empty($references) && ($file->status == FILE_STATUS_PERMANENT || $file->uid != $user->uid || (!$user->uid && empty($_SESSION['anonymous_allowed_file_ids'][$file->fid])))) {

      return;

  }

  // Default to allow access.

  $denied = FALSE;

  // Loop through all references of this file. If a reference explicitly allows

  // access to the field to which this file belongs, no further checks are done

  // and download access is granted. If a reference denies access, eventually

  // existing additional references are checked. If all references were checked

  // and no reference denied access, access is granted as well. If at least one

  // reference denied access, access is denied.

  foreach ($references as $field_name => $field_references) {

    foreach ($field_references as $entity_type => $type_references) {

      foreach ($type_references as $id => $reference) {

        // Try to load $entity and $field.

        $entity = entity_load($entity_type, array($id));

        $entity = reset($entity);

        $field = field_info_field($field_name);

        // Load the field item that references the file.

        $field_item = NULL;

        if ($entity) {

          // Load all field items for that entity.

          $field_items = field_get_items($entity_type, $entity, $field_name);

          // Find the field item with the matching URI.

          foreach ($field_items as $item) {

            if ($item['uri'] == $uri) {

              $field_item = $item;

              break;

            }

          }

        }

        // Check that $entity, $field and $field_item were loaded successfully

        // and check if access to that field is not disallowed. If any of these

        // checks fail, stop checking access for this reference.

        if (empty($entity) || empty($field) || empty($field_item) || !field_access('view', $field, $entity_type, $entity)) {

          $denied = TRUE;

          break;

        }

        // Invoke hook and collect grants/denies for download access.

        // Default to FALSE and let entities overrule this ruling.

        $grants = array('system' => FALSE);

        foreach (module_implements('file_download_access') as $module) {

          $grants = array_merge($grants, array($module => module_invoke($module, 'file_download_access', $field_item, $entity_type, $entity)));

        }

        // Allow other modules to alter the returned grants/denies.

        drupal_alter('file_download_access', $grants, $field_item, $entity_type, $entity);

        if (in_array(TRUE, $grants)) {

          // If TRUE is returned, access is granted and no further checks are

          // necessary.

          $denied = FALSE;

          break 3;

        }

        if (in_array(FALSE, $grants)) {

          // If an implementation returns FALSE, access to this entity is denied

          // but the file could belong to another entity to which the user might

          // have access. Continue with these.

          $denied = TRUE;

        }

      }

    }

  }

  // Access specifically denied.

  if ($denied) {

    return -1;

  }

  // Access is granted.

  $headers = file_get_content_headers($file);

  return $headers;

}

/**

 * Menu callback; Shared Ajax callback for file uploads and deletions.

 *

 * This rebuilds the form element for a particular field item. As long as the

 * form processing is properly encapsulated in the widget element the form

 * should rebuild correctly using FAPI without the need for additional callbacks

 * or processing.

 */

function file_ajax_upload() {

  $form_parents = func_get_args();

  $form_build_id = (string) array_pop($form_parents);

  if (empty($_POST['form_build_id']) || $form_build_id != $_POST['form_build_id']) {

    // Invalid request.

    drupal_set_message(t('An unrecoverable error occurred. The uploaded file likely exceeded the maximum file size (@size) that this server supports.', array('@size' => format_size(file_upload_max_size()))), 'error');

    $commands = array();

    $commands[] = ajax_command_replace(NULL, theme('status_messages'));

    return array('#type' => 'ajax', '#commands' => $commands);

  }

  list($form, $form_state, $form_id, $form_build_id, $commands) = ajax_get_form();

  if (!$form) {

    // Invalid form_build_id.

    drupal_set_message(t('An unrecoverable error occurred. Use of this form has expired. Try reloading the page and submitting again.'), 'error');

    $commands = array();

    $commands[] = ajax_command_replace(NULL, theme('status_messages'));

    return array('#type' => 'ajax', '#commands' => $commands);

  }

  // Get the current element and count the number of files.

  $current_element = $form;

  foreach ($form_parents as $parent) {

    $current_element = $current_element[$parent];

  }

  $current_file_count = isset($current_element['#file_upload_delta']) ? $current_element['#file_upload_delta'] : 0;

  // Process user input. $form and $form_state are modified in the process.

  drupal_process_form($form['#form_id'], $form, $form_state);

  // Retrieve the element to be rendered.

  foreach ($form_parents as $parent) {

    $form = $form[$parent];

  }

  // Add the special Ajax class if a new file was added.

  if (isset($form['#file_upload_delta']) && $current_file_count < $form['#file_upload_delta']) {

    $form[$current_file_count]['#attributes']['class'][] = 'ajax-new-content';

  }

  // Otherwise just add the new content class on a placeholder.

  else {

    $form['#suffix'] .= '<span class="ajax-new-content"></span>';

  }

  $form['#prefix'] .= theme('status_messages');

  $output = drupal_render($form);

  $js = drupal_add_js();

  $settings = drupal_array_merge_deep_array($js['settings']['data']);

  $commands[] = ajax_command_replace(NULL, $output, $settings);

  return array('#type' => 'ajax', '#commands' => $commands);

}

/**

 * Menu callback for upload progress.

 *

 * @param $key

 *   The unique key for this upload process.

 */

function file_ajax_progress($key) {

  $progress = array(

    'message' => t('Starting upload...'),

    'percentage' => -1,

  );

  $implementation = file_progress_implementation();

  if ($implementation == 'uploadprogress') {

    $status = uploadprogress_get_info($key);

    if (isset($status['bytes_uploaded']) && !empty($status['bytes_total'])) {

      $progress['message'] = t('Uploading... (@current of @total)', array('@current' => format_size($status['bytes_uploaded']), '@total' => format_size($status['bytes_total'])));

      $progress['percentage'] = round(100 * $status['bytes_uploaded'] / $status['bytes_total']);

    }

  }

  elseif ($implementation == 'apc') {

    $status = apc_fetch('upload_' . $key);

    if (isset($status['current']) && !empty($status['total'])) {

      $progress['message'] = t('Uploading... (@current of @total)', array('@current' => format_size($status['current']), '@total' => format_size($status['total'])));

      $progress['percentage'] = round(100 * $status['current'] / $status['total']);

    }

  }

  drupal_json_output($progress);

}

/**

 * Determines the preferred upload progress implementation.

 *

 * @return

 *   A string indicating which upload progress system is available. Either "apc"

 *   or "uploadprogress". If neither are available, returns FALSE.

 */

function file_progress_implementation() {

  static $implementation;

  if (!isset($implementation)) {

    $implementation = FALSE;

    // We prefer the PECL extension uploadprogress because it supports multiple

    // simultaneous uploads. APC only supports one at a time.

    if (extension_loaded('uploadprogress')) {

      $implementation = 'uploadprogress';

    }

    elseif (extension_loaded('apc') && ini_get('apc.rfc1867')) {

      $implementation = 'apc';

    }

  }

  return $implementation;

}

/**

 * Implements hook_file_delete().

 */

function file_file_delete($file) {

  // TODO: Remove references to a file that is in-use.

}

/**

 * Process function to expand the managed_file element type.

 *

 * Expands the file type to include Upload and Remove buttons, as well as

 * support for a default value.

 */

function file_managed_file_process($element, &$form_state, $form) {

  // Append the '-upload' to the #id so the field label's 'for' attribute

  // corresponds with the file element.

  $original_id = $element['#id'];

  $element['#id'] .= '-upload';

  $fid = isset($element['#value']['fid']) ? $element['#value']['fid'] : 0;

  // Set some default element properties.

  $element['#progress_indicator'] = empty($element['#progress_indicator']) ? 'none' : $element['#progress_indicator'];

  $element['#file'] = $fid ? file_load($fid) : FALSE;

  $element['#tree'] = TRUE;

  $ajax_settings = array(

    'path' => 'file/ajax/' . implode('/', $element['#array_parents']) . '/' . $form['form_build_id']['#value'],

    'wrapper' => $original_id . '-ajax-wrapper',

    'effect' => 'fade',

    'progress' => array(

      'type' => $element['#progress_indicator'],

      'message' => $element['#progress_message'],

    ),

  );

  // Set up the buttons first since we need to check if they were clicked.

  $element['upload_button'] = array(

    '#name' => implode('_', $element['#parents']) . '_upload_button',

    '#type' => 'submit',

    '#value' => t('Upload'),

    '#validate' => array(),

    '#submit' => array('file_managed_file_submit'),

    '#limit_validation_errors' => array($element['#parents']),

    '#ajax' => $ajax_settings,

    '#weight' => -5,

  );

  // Force the progress indicator for the remove button to be either 'none' or

  // 'throbber', even if the upload button is using something else.

  $ajax_settings['progress']['type'] = ($element['#progress_indicator'] == 'none') ? 'none' : 'throbber';

  $ajax_settings['progress']['message'] = NULL;

  $ajax_settings['effect'] = 'none';

  $element['remove_button'] = array(

    '#name' => implode('_', $element['#parents']) . '_remove_button',

    '#type' => 'submit',

    '#value' => t('Remove'),

    '#validate' => array(),

    '#submit' => array('file_managed_file_submit'),

    '#limit_validation_errors' => array($element['#parents']),

    '#ajax' => $ajax_settings,

    '#weight' => -5,

  );

  $element['fid'] = array(

    '#type' => 'hidden',

    '#value' => $fid,

  );

  // Add progress bar support to the upload if possible.

  if ($element['#progress_indicator'] == 'bar' && $implementation = file_progress_implementation()) {

    $upload_progress_key = mt_rand();

    if ($implementation == 'uploadprogress') {

      $element['UPLOAD_IDENTIFIER'] = array(

        '#type' => 'hidden',

        '#value' => $upload_progress_key,

        '#attributes' => array('class' => array('file-progress')),

        // Uploadprogress extension requires this field to be at the top of the

        // form.

        '#weight' => -20,

      );

    }

    elseif ($implementation == 'apc') {

      $element['APC_UPLOAD_PROGRESS'] = array(

        '#type' => 'hidden',

        '#value' => $upload_progress_key,

        '#attributes' => array('class' => array('file-progress')),

        // Uploadprogress extension requires this field to be at the top of the

        // form.

        '#weight' => -20,

      );

    }

    // Add the upload progress callback.

    $element['upload_button']['#ajax']['progress']['path'] = 'file/progress/' . $upload_progress_key;

  }

  // The file upload field itself.

  $element['upload'] = array(

    '#name' => 'files[' . implode('_', $element['#parents']) . ']',

    '#type' => 'file',

    '#title' => t('Choose a file'),

    '#title_display' => 'invisible',

    '#size' => $element['#size'],

    '#theme_wrappers' => array(),

    '#weight' => -10,

  );

  if ($fid && $element['#file']) {

    $element['filename'] = array(

      '#type' => 'markup',

      '#markup' => theme('file_link', array('file' => $element['#file'])) . ' ',

      '#weight' => -10,

    );

    // Anonymous users who have uploaded a temporary file need a

    // non-session-based token added so file_managed_file_value() can check

    // that they have permission to use this file on subsequent submissions of

    // the same form (for example, after an Ajax upload or form validation

    // error).

    if (!$GLOBALS['user']->uid && $element['#file']->status != FILE_STATUS_PERMANENT) {

      $element['fid_token'] = array(

        '#type' => 'hidden',

        '#value' => drupal_hmac_base64('file-' . $fid, drupal_get_private_key() . drupal_get_hash_salt()),

      );

    }

  }

  // Add the extension list to the page as JavaScript settings.

  if (isset($element['#upload_validators']['file_validate_extensions'][0])) {

    $extension_list = implode(',', array_filter(explode(' ', $element['#upload_validators']['file_validate_extensions'][0])));

    $element['upload']['#attached']['js'] = array(

      array(

        'type' => 'setting',

        'data' => array('file' => array('elements' => array('#' . $element['#id'] => $extension_list)))

      )

    );

  }

  // Prefix and suffix used for Ajax replacement.

  $element['#prefix'] = '<div id="' . $original_id . '-ajax-wrapper">';

  $element['#suffix'] = '</div>';

  return $element;

}

/**

 * The #value_callback for a managed_file type element.

 */

function file_managed_file_value(&$element, $input = FALSE, $form_state = NULL) {

  $fid = 0;

  $force_default = FALSE;

  // Find the current value of this field from the form state.

  $form_state_fid = $form_state['values'];

  foreach ($element['#parents'] as $parent) {

    $form_state_fid = isset($form_state_fid[$parent]) ? $form_state_fid[$parent] : 0;

  }

  if ($element['#extended'] && isset($form_state_fid['fid'])) {

    $fid = $form_state_fid['fid'];

  }

  elseif (is_numeric($form_state_fid)) {

    $fid = $form_state_fid;

  }

  // Process any input and save new uploads.

  if ($input !== FALSE) {

    $return = $input;

    // Uploads take priority over all other values.

    if ($file = file_managed_file_save_upload($element)) {

      $fid = $file->fid;

    }

    else {

      // Check for #filefield_value_callback values.

      // Because FAPI does not allow multiple #value_callback values like it

      // does for #element_validate and #process, this fills the missing

      // functionality to allow File fields to be extended through FAPI.

      if (isset($element['#file_value_callbacks'])) {

        foreach ($element['#file_value_callbacks'] as $callback) {

          $callback($element, $input, $form_state);