<?php
// $Id: file.field.inc,v 1.2 2009/07/20 07:17:15 quicksketch Exp $

/**
 * @file
 * Field hooks to provide an "image" widget for file fields.
 */

/**
 * Implement hook_field_formatter_info().
 */
function image_field_formatter_info() {
  $formatters = array(
    'image' => array(
      'label' => t('Image'),
      'field types' => array('file'),
    ),
    'image_link_content' => array(
      'label' => t('Image linked to content'),
      'field types' => array('file'),
    ),
    'image_link_file' => array(
      'label' => t('Image linked to file'),
      'field types' => array('file'),
    ),
  );

  // TODO: Add image style formatters.

  return $formatters;
}

/**
 * Implement hook_field_widget_info().
 */
function image_field_widget_info() {
  return array(
    'file_image' => array(
      'label' => t('Image'),
      'field types' => array('file'),
      'settings' => array(
        'file_extensions' => 'png gif jpg jpeg',
        'file_directory' => '',
        'progress_indicator' => 'throbber',
        'max_filesize_per_field' => '',
        'max_filesize_per_file' => '',
        'alt_field' => 0,
        'title_field' => 0,
        'caption_field' => 0,
      ),
      'behaviors' => array(
        'multiple values' => FIELD_BEHAVIOR_DEFAULT,
        'default value' => FIELD_BEHAVIOR_NONE,
      ),
    ),
  );
}

/**
 * Implementation of hook_field_widget().
 */
function image_field_widget(&$form, &$form_state, $field, $instance, $items, $delta = 0) {
  $form['#attributes'] = array('enctype' => 'multipart/form-data');

  $item = array(
    'fid' => 0,
    'list' => $field['settings']['list_default'],
    'data' => array('alt' => '', 'title' => '', 'caption' => ''),
  );

  if (isset($items[$delta])) {
    $item = array_merge($item, $items[$delta]);
  }

  // Essentially we use the managed_file type, extended with some enhancements.
  $element_info = element_info('managed_file');
  $element = array(
    '#title' => $instance['label'],
    '#type' => 'managed_file',
    '#default_value' => $item,
    '#required' => $instance['required'],
    '#save_directory' => file_field_widget_file_path($instance),
    '#upload_validators' => file_field_widget_upload_validators($field, $instance),
    '#value_callback' => 'file_field_widget_value',
    '#process' => array_merge($element_info['#process'], array('image_field_widget_process')),
    // Allows this field to return an array instead of a single value.
    '#extended' => TRUE,
  );

  return $element;
}

/**
 * An element #process callback for the file_image field type.
 *
 * Expands the file_image type to include the alt, title, and caption fields.
 */
function image_field_widget_process($element, &$form_state, $form) {
  $item = $element['#value'];
  $item['fid'] = $element['fid']['#value'];

  $field = field_info_field($element['#field_name']);
  $instance = field_info_instance($element['#field_name'], $element['#bundle']);
  $defaults = field_info_widget_settings($instance['widget']['type']);
  $settings = array_merge($defaults, $instance['widget']['settings']);

  $element['#theme'] = 'image_widget';

  // Add the list field if enabled.
  if ($field['settings']['list_field'] && $item['fid']) {
    $element['list'] = array(
      '#type' => empty($item['fid']) ? 'hidden' : 'checkbox',
      '#title' => t('Include file in display'),
      '#value' => isset($item['list']) ? $item['list'] : $field['list_default'],
      '#attributes' => array('class' => 'file-list'),
    );
  }
  else {
    $element['list'] = array(
      '#type' => 'hidden',
      '#value' => '1',
    );
  }

  // Data placeholder for widgets to store additional data.
  $element['data'] = array(
    '#tree' => 'true',
    '#title' => t('File data'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#access' => (bool) $item['fid'],
  );

  // Check if using the default alt text and replace tokens.
  $default_alt = (!$settings['alt_field'] || (empty($file['status']) && empty($file['data']['alt'])));
  $element['data']['alt'] = array(
    '#title' => t('Alternate Text'),
    '#type' => $settings['alt_field'] ? 'textfield' : 'value',
    '#default_value' => $default_alt ? $settings['alt_default'] : $file['data']['alt_default'],
    '#description' => t('This text will be used by screen readers, search engines, or when the image cannot be loaded.'),
    '#maxlength' => variable_get('image_alt_length', 80), // See http://www.gawds.org/show.php?contentid=28.
  );
  if ($element['data']['alt']['#type'] == 'value') {
    $element['data']['alt']['#value'] = $settings['alt'];
  }

  // Check if using the default title and replace tokens.
  $default_title = (!$settings['title_field'] || (empty($item['status']) && empty($item['data']['title'])));

  // If the custom title is enabled, input type defaults to textfield.
  if (!empty($settings['title_custom'])) {
    $title_type = !empty($settings['title_type']) ? $settings['title_type'] : 'textfield';
  }
  else {
    $title_type = 'value';
  }

  $element['data']['title'] = array(
    '#type' => $title_type,
    '#title' => t('Title'),
    '#default_value' => $default_title ? $settings['title_default'] : $file['data']['title_default'],
    '#description' => t('The title is used as a tool tip when the user hovers the mouse over the image.'),
    '#maxlength' => variable_get('image_title_length', 500),
  );
  if ($element['data']['title']['#type'] == 'value') {
    $element['data']['title']['#value'] = $settings['title_default'];
  }

  return $element;
}

function theme_image_widget($element) {
  $output = '';
  $output .= '<div class="form-managed-file file-widget clearfix">';
  if ($element['fid']['#value'] != 0) {
    $output .= '<div class="widget-preview">';
    $output .= '<div class="thumbnail">' . theme('image', $element['filepath']) . '</div>';
    $output .= '<div class="filesize">' . format_size($element['#file']->filesize) .'</div>';
    $output .= '<div class="filemime">' . check_plain($element['#file']->filemime) .'</div>';
    $output .= '</div>';
    $output .= '<div class="widget-edit">';
    $output .= drupal_render_children($element);
    $output .= '</div>';
  }
  else {
    $output .= drupal_render_children($element);
  }
  $output .= '</div>';

  return $output;
}

/**
 * Theme function for 'image' file field formatter.
 */
function theme_field_formatter_image($element) {
  return theme('image', $element['#item']['filepath'], $element['#item']['data']['alt'], $element['#item']['data']['title']);
}

/**
 * Theme function for 'image_link_content' file field formatter.
 */
function theme_field_formatter_image_link_content($element) {
  list($id, $vid, $bundle) = field_attach_extract_ids($element['#object_type'], $element['#object']);
  l(theme('field_formatter_image', $element), $element['#object_type'] . '/' . $id);
}

/**
 * Theme function for 'image_link_file' file field formatter.
 */
function theme_field_formatter_image_link_file($element) {
  l(theme('field_formatter_image', $element), file_create_url($element['#item']['filepath']));
}