<?php

/**
 * Implements hook_field_widget_info().
 */
function emfield_field_widget_info() {
  return array(
    'enfield_widget' => array(
      'label' => t('Embedded media field'),
      'field types' => array('file'),
      'settings' => array('size' => 60),
      'behaviors' => array(
        'multiple values' => FIELD_BEHAVIOR_DEFAULT,
        'default value' => FIELD_BEHAVIOR_DEFAULT,
      ),
    ),
  );
}

/**
 * Implements hook_field_widget_settings_form().
 */
function emfield_field_widget_settings_form($field, $instance) {
  $widget = $instance['widget'];
  $settings = $widget['settings'];

  $form['size'] = array(
    '#type' => 'textfield',
    '#title' => t('Size of textfield'),
    '#default_value' => $settings['size'],
    '#required' => TRUE,
    '#element_validate' => array('element_validate_integer_positive'),
  );

  return $form;
}

/**
 * Implements hook_field_widget_error().
 */
function emfield_field_widget_error($element, $error, $form, &$form_state) {
  form_error($element['fid'], $error['message']);
}

/**
 * Implements hook_field_widget_form().
 */
function emfield_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element) {
  $element += array(
    '#type' => 'textfield',
    '#default_value' => isset($items[$delta]) ? $items[$delta] : '',
    '#size' => $instance['widget']['settings']['size'],
    '#maxlength' => 1024,
    '#element_validate' => array('emfield_widget_validate'),
    '#value_callback' => 'emfield_widget_value',
  );
  return array('fid' => $element, 'display' => array(
      '#type' => 'value',
      '#value' => 1,
    ));
}

/**
 * Validation callback for an emfield element.
 */
function emfield_widget_validate($element, &$form_state, $form) {
  $field = field_widget_field($element, $form_state);
  $instance = field_widget_instance($element, $form_state);

  $value = $element['#value'];
  $fid = NULL;

  if (!empty($value)) {
    // Get the fid of a referencable file from the entered url.
    try {
      $provider = media_internet_get_provider($value);
    }
    catch (Exception $error) {
      form_error($element, t('%name: Found no valid media with that url.', array('%name' => $instance['label'])));
      return;
    }
    $file = $provider->save();
    $fid = $file->fid;
  }
  // Set the element's value as the file id that was extracted from the entered
  // input.
  form_set_value($element, $fid, $form_state);
}


/**
 * Value callback for an emfield element.
 *
 * Replace the file fid with a url.
 */
function emfield_widget_value($element, $input = FALSE, $form_state) {
  if ($input === FALSE) {
    // We're building the displayed 'default value': expand the raw fid into
    // "uri [fid:n]".
    $fid = $element['#default_value'];
    if (!empty($fid)) {
      $q = db_select('file_managed', 'f');
      $q->addField('f', 'uri');
      $q->addTag('file_access')
        ->condition('f.fid', $fid['fid'])
        ->range(0, 1);
      $result = $q->execute();
      // @todo If no result (file doesn't exist or no access).
      $uri = $result->fetchField();
      return file_create_url($uri);
    }
  }
}

/**
 * Implements hook_content_migrate_field_alter().
 */
function emfield_content_migrate_field_alter(&$field_value, &$instance_value) {
  if (in_array($field_value['module'], array('emfield', 'emimage', 'emaudio', 'emvideo'))) {
    $field_value['module'] = 'file';
    $field_value['type'] = 'file';
    // TODO: need to convert settings etc for this field to the D7 version.
  }
}

/**
 * Implements hook_content_migrate_instance_alter().
 */
function emfield_content_migrate_instance_alter(&$instance_value, &$field_value) {
  if (in_array($instance_value['widget']['module'], array('emfield', 'emimage', 'emaudio', 'emvideo'))) {
    $instance_value['widget']['module'] = 'media';
    $instance_value['widget']['type'] = 'media_generic';
    $instance_value['widget_type'] = 'media_generic';
    // TODO: need to convert settings etc to the D7 version.
  }
}

/**
 * Implements hook_content_migrate_data_record_alter().
 */
function emfield_content_migrate_data_record_alter(&$record, &$field, $instance) {
  if (!empty($record[$field['field_name'] . '_embed'])) {
    $provider = media_internet_get_provider($record[$field['field_name'] . '_embed']);
    // This is a hack to stop content migrate from misreading the content.
    unset($field['type']);
    if ($provider) {
        $file = $provider->save();
        $record[$field['field_name'] . '_fid'] = $file->fid;
    }
  }
}

/**
 * Implements hook_module_implements_alter();
 */
function emfield_module_implements_alter(&$implementations, $hook) {
  if ($hook == 'content_migrate_data_record_alter') {
    // Move emfield_content_migrate_data_record_alter() to the top of the list.
    $group = $implementations['emfield'];
    unset($implementations['emfield']);
    $implementations = array('emfield'  => $group) + $implementations;
  }
}