<?php

/**
 * Implements hook_hook_info().
 */
function field_formatter_settings_hook_info() {
  $hooks = array(
    'field_formatter_settings_form_alter',
    'field_formatter_settings_summary_alter',
  );

  return array_fill_keys($hooks, array('group' => 'field'));
}

/**
 * Get the formatter settings for a field instance and view mode.
 *
 * @param string $field_name
 * @param string $display
 * @param string $bundle
 * @param string $view_mode
 *
 * @return array
 */
function field_formatter_settings_get_instance_display_settings($entity_type, $field_name, $bundle, $view_mode) {
  // There is no bundle for this entity type so the bundle name in the
  // entity_type name.
  if (empty($bundle)) {
    $bundle = $entity_type;
  }

  // Fetch the instance settings and default display settings.
  $info = field_info_instance($entity_type, $field_name, $bundle);
  $defaults = $info['display']['default']['settings'];

  if (isset($info['display'][$view_mode]['settings'])) {
    return $info['display'][$view_mode]['settings'] + $defaults;
  }
  else {
    return $defaults;
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function field_formatter_settings_form_field_ui_display_overview_form_alter(&$form, &$form_state) {
  $entity_type = $form['#entity_type'];
  $bundle = $form['#bundle'];
  $view_mode = $form['#view_mode'];

  // Gather type information.
  $instances = field_info_instances($entity_type, $bundle);
  $field_types = field_info_field_types();
  $extra_fields = field_info_extra_fields($entity_type, $bundle, 'display');

  $table = &$form['fields'];

  // Field rows.
  foreach ($instances as $name => $instance) {
    $field = field_info_field($instance['field_name']);
    $display = $instance['display'][$view_mode];

    // Check the currently selected formatter, and merge persisted values for
    // formatter settings.
    if (isset($form_state['values']['fields'][$name]['type'])) {
      $formatter_type = $form_state['values']['fields'][$name]['type'];
    }
    else {
      $formatter_type = $display['type'];
    }
    if (isset($form_state['formatter_settings'][$name])) {
      $settings = $form_state['formatter_settings'][$name];
    }
    else {
      $settings = $display['settings'];
    }
    $settings += field_info_formatter_settings($formatter_type);

    $instance['display'][$view_mode]['type'] = $formatter_type;
    $formatter = field_info_formatter_types($formatter_type);
    $instance['display'][$view_mode]['module'] = $formatter['module'];
    $instance['display'][$view_mode]['settings'] = $settings;

    // Base button element for the various formatter settings actions.
    $base_button = array(
      '#submit' => array('field_ui_display_overview_multistep_submit'),
      '#ajax' => array(
        'callback' => 'field_ui_display_overview_multistep_js',
        'wrapper' => 'field-display-overview-wrapper',
        'effect' => 'fade',
      ),
      '#field_name' => $name,
    );

    if ($form_state['formatter_settings_edit'] == $name) {
      $settings_form = isset($table[$name]['format']['settings_edit_form']['settings']) ? $table[$name]['format']['settings_edit_form']['settings'] : array();

      // Allow other modules to alter the formater settings form.
      $context = array(
        'module' => $formatter['module'],
        'formatter' => $formatter,
        'field' => $field,
        'instance' => $instance,
        'view_mode' => $view_mode,
        'form' => $form,
        'form_state' => $form_state,
      );
      drupal_alter('field_formatter_settings_form', $settings_form, $context);

      if ($settings_form) {
        $table[$name]['format']['#cell_attributes'] = array('colspan' => 3);
        $table[$name]['format']['settings_edit_form'] = array(
          '#type' => 'container',
          '#attributes' => array('class' => array('field-formatter-settings-edit-form')),
          '#parents' => array('fields', $name, 'settings_edit_form'),
          'label' => array(
            '#markup' => t('Format settings:') . ' <span class="formatter-name">' . $formatter['label'] . '</span>',
          ),
          'settings' => $settings_form,
          'actions' => array(
            '#type' => 'actions',
            'save_settings' => $base_button + array(
              '#type' => 'submit',
              '#name' => $name . '_formatter_settings_update',
              '#value' => t('Update'),
              '#op' => 'update',
            ),
            'cancel_settings' => $base_button + array(
              '#type' => 'submit',
              '#name' => $name . '_formatter_settings_cancel',
              '#value' => t('Cancel'),
              '#op' => 'cancel',
              // Do not check errors for the 'Cancel' button, but make sure we
              // get the value of the 'formatter type' select.
              '#limit_validation_errors' => array(array('fields', $name, 'type')),
            ),
          ),
        );
        $table[$name]['#attributes']['class'][] = 'field-formatter-settings-editing';
      }
    }
    else {
      // Display a summary of the current formatter settings.
      $summary = module_invoke($formatter['module'], 'field_formatter_settings_summary', $field, $instance, $view_mode);

      // Allow other modules to alter the formatter summary.
      $context = array(
        'field' => $field,
        'instance' => $instance,
        'view_mode' => $view_mode,
      );
      drupal_alter('field_formatter_settings_summary', $summary, $context);

      $table[$name]['settings_summary'] = array();
      $table[$name]['settings_edit'] = array();
      if ($summary) {
        $table[$name]['settings_summary'] = array(
          '#markup' => '<div class="field-formatter-summary">' . $summary . '</div>',
          '#cell_attributes' => array('class' => array('field-formatter-summary-cell')),
        );
        $table[$name]['settings_edit'] = $base_button + array(
          '#type' => 'image_button',
          '#name' => $name . '_formatter_settings_edit',
          '#src' => 'misc/configure.png',
          '#attributes' => array('class' => array('field-formatter-settings-edit'), 'alt' => t('Edit')),
          '#op' => 'edit',
          // Do not check errors for the 'Edit' button, but make sure we get
          // the value of the 'formatter type' select.
          '#limit_validation_errors' => array(array('fields', $name, 'type')),
          '#prefix' => '<div class="field-formatter-settings-edit-wrapper">',
          '#suffix' => '</div>',
        );
      }
    }
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Support altering formatter settings for field handlers in Views. Unlike the
 * Field UI page, this does not require the settings summary hook to be
 * invoked to work.
 */
function field_formatter_settings_form_views_ui_config_item_form_alter(&$form, &$form_state) {
  $handler = $form_state['handler'];
  if ($handler instanceof views_handler_field_field) {
    $context = array(
      'module' => $handler->field_info['module'],
      'formatter' => $handler->field_info['type'],
      'field' => field_info_field($handler->options['field']),
      'instance' => $handler->instance,
      'view_mode' => '_custom', // Same view mode as field_view_field().
      'form' => $form,
      'form_state' => $form_state,
    );
    drupal_alter('field_formatter_settings_form', $form['options']['settings'], $context);
  }
}