<?php

/**

 * @file

 * Field forms management.

 */

/**

 * Creates a form element for a field and can populate it with a default value.

 *

 * If the form element is not associated with an entity (i.e., $entity is NULL)

 * field_get_default_value will be called to supply the default value for the

 * field. Also allows other modules to alter the form element by implementing

 * their own hooks.

 *

 * @param $entity_type

 *   The type of entity (for example 'node' or 'user') that the field belongs

 *   to.

 * @param $entity

 *   The entity object that the field belongs to. This may be NULL if creating a

 *   form element with a default value.

 * @param $field

 *   An array representing the field whose editing element is being created.

 * @param $instance

 *   An array representing the structure for $field in its current context.

 * @param $langcode

 *   The language associated with the field.

 * @param $items

 *   An array of the field values. When creating a new entity this may be NULL

 *   or an empty array to use default values.

 * @param $form

 *   An array representing the form that the editing element will be attached

 *   to. 

 * @param $form_state

 *   An array containing the current state of the form.

 * @param $get_delta

 *   Used to get only a specific delta value of a multiple value field.

 *

 * @return

 *  The form element array created for this field.

 */

function field_default_form($entity_type, $entity, $field, $instance, $langcode, $items, &$form, &$form_state, $get_delta = NULL) {

  // This could be called with no entity, as when a UI module creates a

  // dummy form to set default values.

  if ($entity) {

    list($id, , ) = entity_extract_ids($entity_type, $entity);

  }

  $parents = $form['#parents'];

  $addition = array();

  $field_name = $field['field_name'];

  $addition[$field_name] = array();

  // Populate widgets with default values when creating a new entity.

  if (empty($items) && empty($id)) {

    $items = field_get_default_value($entity_type, $entity, $field, $instance, $langcode);

  }

  // Let modules alter the widget properties.

  $context = array(

    'entity_type' => $entity_type,

    'entity' => $entity,

    'field' => $field,

    'instance' => $instance,

  );

  drupal_alter(array('field_widget_properties', 'field_widget_properties_' . $entity_type), $instance['widget'], $context);

  // Collect widget elements.

  $elements = array();

  // Store field information in $form_state.

  if (!field_form_get_state($parents, $field_name, $langcode, $form_state)) {

    $field_state = array(

      'field' => $field,

      'instance' => $instance,

      'items_count' => count($items),

      'array_parents' => array(),

      'errors' => array(),

    );

    field_form_set_state($parents, $field_name, $langcode, $form_state, $field_state);

  }

  // If field module handles multiple values for this form element, and we are

  // displaying an individual element, process the multiple value form.

  if (!isset($get_delta) && field_behaviors_widget('multiple values', $instance) == FIELD_BEHAVIOR_DEFAULT) {

    // Store the entity in the form.

    $form['#entity'] = $entity;

    $elements = field_multiple_value_form($field, $instance, $langcode, $items, $form, $form_state);

  }

  // If the widget is handling multiple values (e.g Options), or if we are

  // displaying an individual element, just get a single form element and make

  // it the $delta value.

  else {

    $delta = isset($get_delta) ? $get_delta : 0;

    $function = $instance['widget']['module'] . '_field_widget_form';

    if (function_exists($function)) {

      $element = array(

        '#entity' => $entity,

        '#entity_type' => $instance['entity_type'],

        '#bundle' => $instance['bundle'],

        '#field_name' => $field_name,

        '#language' => $langcode,

        '#field_parents' => $parents,

        '#columns' => array_keys($field['columns']),

        '#title' => check_plain($instance['label']),

        '#description' => field_filter_xss($instance['description']),

        // Only the first widget should be required.

        '#required' => $delta == 0 && $instance['required'],

        '#delta' => $delta,

      );

      if ($element = $function($form, $form_state, $field, $instance, $langcode, $items, $delta, $element)) {

        // Allow modules to alter the field widget form element.

        $context = array(

          'form' => $form,

          'field' => $field,

          'instance' => $instance,

          'langcode' => $langcode,

          'items' => $items,

          'delta' => $delta,

        );

        drupal_alter(array('field_widget_form', 'field_widget_' . $instance['widget']['type'] . '_form'), $element, $form_state, $context);

        // If we're processing a specific delta value for a field where the

        // field module handles multiples, set the delta in the result.

        // For fields that handle their own processing, we can't make

        // assumptions about how the field is structured, just merge in the

        // returned element.

        if (field_behaviors_widget('multiple values', $instance) == FIELD_BEHAVIOR_DEFAULT) {

          $elements[$delta] = $element;

        }

        else {

          $elements = $element;

        }

      }

    }

  }

  // Also aid in theming of field widgets by rendering a classified container.

  $addition[$field_name] = array(

    '#type' => 'container',

    '#attributes' => array(

      'class' => array(

        'field-type-' . drupal_html_class($field['type']),

        'field-name-' . drupal_html_class($field_name),

        'field-widget-' . drupal_html_class($instance['widget']['type']),

      ),

    ),

    '#weight' => $instance['widget']['weight'],

  );

  // Populate the 'array_parents' information in $form_state['field'] after

  // the form is built, so that we catch changes in the form structure performed

  // in alter() hooks.

  $elements['#after_build'][] = 'field_form_element_after_build';

  $elements['#field_name'] = $field_name;

  $elements['#language'] = $langcode;

  $elements['#field_parents'] = $parents;

  $addition[$field_name] += array(

    '#tree' => TRUE,

    // The '#language' key can be used to access the field's form element

    // when $langcode is unknown.

    '#language' => $langcode,

    $langcode => $elements,

    '#access' => field_access('edit', $field, $entity_type, $entity),

  );

  return $addition;

}

/**

 * Special handling to create form elements for multiple values.

 *

 * Handles generic features for multiple fields:

 * - number of widgets

 * - AHAH-'add more' button

 * - drag-n-drop value reordering

 */

function field_multiple_value_form($field, $instance, $langcode, $items, &$form, &$form_state) {

  $field_name = $field['field_name'];

  $parents = $form['#parents'];

  // Determine the number of widgets to display.

  switch ($field['cardinality']) {

    case FIELD_CARDINALITY_UNLIMITED:

      $field_state = field_form_get_state($parents, $field_name, $langcode, $form_state);

      $max = $field_state['items_count'];

      break;

    default:

      $max = $field['cardinality'] - 1;

      break;

  }

  $title = check_plain($instance['label']);

  $description = field_filter_xss($instance['description']);

  $id_prefix = implode('-', array_merge($parents, array($field_name)));

  $wrapper_id = drupal_html_id($id_prefix . '-add-more-wrapper');

  $field_elements = array();

  $function = $instance['widget']['module'] . '_field_widget_form';

  if (function_exists($function)) {

    for ($delta = 0; $delta <= $max; $delta++) {

      $multiple = $field['cardinality'] > 1 || $field['cardinality'] == FIELD_CARDINALITY_UNLIMITED;

      $element = array(

        '#entity_type' => $instance['entity_type'],

        '#entity' => $form['#entity'],

        '#bundle' => $instance['bundle'],

        '#field_name' => $field_name,

        '#language' => $langcode,

        '#field_parents' => $parents,

        '#columns' => array_keys($field['columns']),

        // For multiple fields, title and description are handled by the wrapping table.

        '#title' => $multiple ? '' : $title,

        '#description' => $multiple ? '' : $description,

        // Only the first widget should be required.

        '#required' => $delta == 0 && $instance['required'],

        '#delta' => $delta,

        '#weight' => $delta,

      );

      if ($element = $function($form, $form_state, $field, $instance, $langcode, $items, $delta, $element)) {

        // Input field for the delta (drag-n-drop reordering).

        if ($multiple) {

          // We name the element '_weight' to avoid clashing with elements

          // defined by widget.

          $element['_weight'] = array(

            '#type' => 'weight',

            '#title' => t('Weight for row @number', array('@number' => $delta + 1)),

            '#title_display' => 'invisible',

             // Note: this 'delta' is the FAPI 'weight' element's property.

            '#delta' => $max,

            '#default_value' => isset($items[$delta]['_weight']) ? $items[$delta]['_weight'] : $delta,

            '#weight' => 100,

          );

        }

        // Allow modules to alter the field widget form element.

        $context = array(

          'form' => $form,

          'field' => $field,

          'instance' => $instance,

          'langcode' => $langcode,

          'items' => $items,

          'delta' => $delta,

        );

        drupal_alter(array('field_widget_form', 'field_widget_' . $instance['widget']['type'] . '_form'), $element, $form_state, $context);

        $field_elements[$delta] = $element;

      }

    }

    if ($field_elements) {

      $field_elements += array(

        '#theme' => 'field_multiple_value_form',

        '#field_name' => $field['field_name'],

        '#cardinality' => $field['cardinality'],

        '#title' => $title,

        '#required' => $instance['required'],

        '#description' => $description,

        '#prefix' => '<div id="' . $wrapper_id . '">',

        '#suffix' => '</div>',

        '#max_delta' => $max,

      );

      // Add 'add more' button, if not working with a programmed form.

      if ($field['cardinality'] == FIELD_CARDINALITY_UNLIMITED && empty($form_state['programmed'])) {

        $field_elements['add_more'] = array(

          '#type' => 'submit',

          '#name' => strtr($id_prefix, '-', '_') . '_add_more',

          '#value' => t('Add another item'),

          '#attributes' => array('class' => array('field-add-more-submit')),

          '#limit_validation_errors' => array(array_merge($parents, array($field_name, $langcode))),

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

          '#ajax' => array(

            'callback' => 'field_add_more_js',

            'wrapper' => $wrapper_id,

            'effect' => 'fade',

          ),

        );

      }

    }

  }

  return $field_elements;

}

/**

 * Returns HTML for an individual form element.

 *

 * Combine multiple values into a table with drag-n-drop reordering.

 * TODO : convert to a template.

 *

 * @param $variables

 *   An associative array containing:

 *   - element: A render element representing the form element.

 *

 * @ingroup themeable

 */

function theme_field_multiple_value_form($variables) {

  $element = $variables['element'];

  $output = '';

  if ($element['#cardinality'] > 1 || $element['#cardinality'] == FIELD_CARDINALITY_UNLIMITED) {

    $table_id = drupal_html_id($element['#field_name'] . '_values');

    $order_class = $element['#field_name'] . '-delta-order';

    $required = !empty($element['#required']) ? theme('form_required_marker', $variables) : '';

    $header = array(

      array(

        'data' => '<label>' . t('!title !required', array('!title' => $element['#title'], '!required' => $required)) . "</label>",

        'colspan' => 2,

        'class' => array('field-label'),

      ),

      t('Order'),

    );

    $rows = array();

    // Sort items according to '_weight' (needed when the form comes back after

    // preview or failed validation)

    $items = array();

    foreach (element_children($element) as $key) {

      if ($key === 'add_more') {

        $add_more_button = &$element[$key];

      }

      else {

        $items[] = &$element[$key];

      }

    }

    usort($items, '_field_sort_items_value_helper');

    // Add the items as table rows.

    foreach ($items as $key => $item) {

      $item['_weight']['#attributes']['class'] = array($order_class);

      $delta_element = drupal_render($item['_weight']);

      $cells = array(

        array('data' => '', 'class' => array('field-multiple-drag')),

        drupal_render($item),

        array('data' => $delta_element, 'class' => array('delta-order')),

      );

      $rows[] = array(

        'data' => $cells,

        'class' => array('draggable'),

      );

    }

    $output = '<div class="form-item">';

    $output .= theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => $table_id, 'class' => array('field-multiple-table'))));

    $output .= $element['#description'] ? '<div class="description">' . $element['#description'] . '</div>' : '';

    $output .= '<div class="clearfix">' . drupal_render($add_more_button) . '</div>';

    $output .= '</div>';

    drupal_add_tabledrag($table_id, 'order', 'sibling', $order_class);

  }

  else {

    foreach (element_children($element) as $key) {

      $output .= drupal_render($element[$key]);

    }

  }

  return $output;

}

/**

 * #after_build callback for field elements in a form.

 *

 * This stores the final location of the field within the form structure so

 * that field_default_form_errors() can assign validation errors to the right

 * form element.

 *

 * @see field_default_form_errors()

 */

function field_form_element_after_build($element, &$form_state) {

  $parents = $element['#field_parents'];

  $field_name = $element['#field_name'];

  $langcode = $element['#language'];

  $field_state = field_form_get_state($parents, $field_name, $langcode, $form_state);

  $field_state['array_parents'] = $element['#array_parents'];

  field_form_set_state($parents, $field_name, $langcode, $form_state, $field_state);

  return $element;

}

/**

 * Transfer field-level validation errors to widgets.

 */

function field_default_form_errors($entity_type, $entity, $field, $instance, $langcode, $items, $form, &$form_state) {

  $field_state = field_form_get_state($form['#parents'], $field['field_name'], $langcode, $form_state);

  if (!empty($field_state['errors'])) {

    // Locate the correct element in the form.

    $element = drupal_array_get_nested_value($form_state['complete form'], $field_state['array_parents']);

    // Only set errors if the element is accessible.

    if (!isset($element['#access']) || $element['#access']) {

      $function = $instance['widget']['module'] . '_field_widget_error';

      $function_exists = function_exists($function);

      $multiple_widget = field_behaviors_widget('multiple values', $instance) != FIELD_BEHAVIOR_DEFAULT;

      foreach ($field_state['errors'] as $delta => $delta_errors) {

        // For multiple single-value widgets, pass errors by delta.

        // For a multiple-value widget, pass all errors to the main widget.

        $error_element = $multiple_widget ? $element : $element[$delta];

        foreach ($delta_errors as $error) {

          if ($function_exists) {

            $function($error_element, $error, $form, $form_state);

          }

          else {

            // Make sure that errors are reported (even incorrectly flagged) if