<?php

/**
 * @file
 * The Select (or other) module.
 *
 * This file handles the Forms API element, as well as the select_or_other_none
 * theme which is used by the field widget.
 */

// Include the inc files.
module_load_include('inc', 'select_or_other', 'select_or_other.test_form');
module_load_include('inc', 'select_or_other', 'select_or_other.field_widget');

/**
 * Implements hook_theme().
 */
function select_or_other_theme() {
  return array(
    'select_or_other' => array(
      'render element' => 'element',
    ),
    'select_or_other_none' => array(
      'variables' => array(
        'instance' => NULL,
        'option' => NULL,
      ),
    ),
  );

}

/**
 * Theme a Select (or other) element.
 */
function theme_select_or_other($variables) {
  $element = $variables['element'];

  $output = "<div class=\"select-or-other\">\n";
  $output .= drupal_render_children($element) . "\n";
  $output .= "</div>\n";
  return $output;
}

/**
 * Implements hook_element_info().
 */
function select_or_other_element_info() {
  return array(
    'select_or_other' => array(
      '#select_type' => 'select',
      '#input' => TRUE,
      '#multiple' => FALSE,
      '#disabled' => FALSE,
      '#default_value' => NULL,
      '#process' => array('select_or_other_element_process'),
      '#element_validate' => array('select_or_other_element_validate'),
      '#other' => t('Other'),
      '#theme' => 'select_or_other',
      '#theme_wrappers' => array('form_element'),
    ),
  );
}

/**
 * Implements form_type_hook_value().
 */
function form_type_select_or_other_field_value($element, $edit, $form_state) {
  if (func_num_args() == 1) {
    return $element['#default_value'];
  }
  return $edit;
}

/**
 * Process callback for a Select (or other) element.
 */
function select_or_other_element_process($element, &$form_state) {
  $element['#tree'] = TRUE;
  $element['#processed'] = TRUE;

  // Load the JS file to hide/show the 'other' box when needed.
  $element['#attached']['js'][] = drupal_get_path('module', 'select_or_other') . '/select_or_other.js';

  // Create the main select box
  // Note that #title, #title_display, #default_value, #disabled, #multiple,
  // #required, #size, #options, and #attributes are passed to the select box
  // from the main element automatically.

  $element['select'] = array(
    '#type' => $element['#select_type'],
    '#title' => $element['#title'],
    '#title_display' => $element['#title_display'],
    '#default_value' => isset($element['#default_value']) ? $element['#default_value'] : NULL,
    '#disabled' => $element['#disabled'],
    '#multiple' => $element['#multiple'],
    '#required' => $element['#required'],
    '#size' => isset($element['#size']) ? $element['#size'] : NULL,
    '#options' => $element['#options'],
    '#attributes' => $element['#attributes'],
    '#weight' => 10,
  );

  foreach(array('#empty_option', '#empty_value') as $key){
    if (isset($element[$key])) {
      $element['select'][$key] = $element[$key];
    };
  }

  // Remove the default value on the container level so it doesn't get rendered there.
  $element['#value'] = NULL;
  // Remove the required parameter so FAPI doesn't force us to fill in the textfield.
  $element['#required'] = NULL;

  // Now we must handle the default values.
  $other_default = array();

  // Easier to work with the defaults if they are an array.
  if (!is_array($element['select']['#default_value'])) {
    $element['select']['#default_value'] = array(
      $element['select']['#default_value'],
    );
  }


  // Process the default value.
  foreach ($element['select']['#default_value'] as $key => $val) {

    if ($val
      && isset($element['select']['#options'])
      && is_array($element['select']['#options'])
      && !select_or_other_multi_array_key_exists($val, $element['select']['#options'])
      && !in_array($val, $element['select']['#options'])) {

      // Not a valid option - add it to 'other'.
      if ($element['#other_unknown_defaults'] == 'other') {

        if ($element['#other_delimiter']) {
          $other_default[] = $val;
        }
        else {
          $other_default = array($val);
        }
        // Remove it from the select's default value.
        unset($element['select']['#default_value'][$key]);

      }
      // Also checks 'available' because if that setting is newly set, after data is already stored, it should behave like 'append'.
      elseif ($element['#other_unknown_defaults'] == 'append' || $element['#other_unknown_defaults'] == 'available') {
        $element['select']['#options'][$val] = $val;
      }

    }
  }

  // If the expected default value is a string/integer, remove the array wrapper.
  if ($element['#select_type'] == 'radios' || ($element['#select_type'] == 'select' && !$element['#multiple'])) {
    $element['select']['#default_value'] = reset($element['select']['#default_value']);
  }

  $other_default_string = '';
  if (!empty($other_default)) {
    $other_default_string = implode($element['#other_delimiter'], $other_default);
    if (is_array($element['select']['#default_value'])) {
      $element['select']['#default_value'][] = 'select_or_other';
    }
    else {
      $element['select']['#default_value'] = 'select_or_other';
    }
  }

  // Add in the 'other' option.
  $element['select']['#options']['select_or_other'] = $element['#other'];

  // Create the 'other' textfield without the required attribute, if any.
  $element['other'] = array(
    '#type' => 'textfield',
    '#weight' => 20,
    '#default_value' => $other_default_string,
    '#disabled' => $element['#disabled'],
    '#attributes' => array_diff_key($element['#attributes'], array('required' => NULL)),
  );

  // Populate properties set specifically as #select_property or #other_property
  $sub_elements = array('select', 'other');
  foreach ($sub_elements as $sub_element) {
    foreach ($element as $key => $value) {
    if (strpos($key, '#' . $sub_element . '_') === 0) {
        $element[$sub_element][str_replace('#' . $sub_element . '_', '#', $key)] = $value;

      }
    }
    // Also add in a custom class for each.
    $element[$sub_element]['#attributes']['class'][] = 'select-or-other-' . $sub_element;
  }
  if (!empty($element['#maxlength'])) {
    $element['other']['#maxlength'] = $element['#maxlength'];
  }
  if (isset($element['#other_size'])) {
    $element['other']['#size'] = $element['#other_size'];
  }

  // Hide the title from the wrapper.
  $element['#title'] = NULL;

  return $element;
}

/**
 * Element validate callback for a Select (or other) element.
 */
function select_or_other_element_validate($element, &$form_state) {
  $other_selected = FALSE;
  if (is_array($element['select']['#value']) && isset($element['select']['#value']['select_or_other'])) {
    // This is a multiselect. assoc arrays
    $other_selected = TRUE;
    $value = $element['select']['#value'];
    unset($value['select_or_other']);
    $value[$element['other']['#value']] = $element['other']['#value'];
  }
  elseif (is_string($element['select']['#value']) && $element['select']['#value'] == 'select_or_other') {
    // This is a single select.
    $other_selected = TRUE;
    $value = $element['other']['#value'];
  }
  else {
    $value = $element['select']['#value'];
  }
  if ($other_selected && $element['other']['#value'] === '') {
    form_error($element['other'], t('!title field is required.', array('!title' => $element['select']['#title'])));
  }
  if (isset($value)) {
    form_set_value($element, $value, $form_state);
    $form_state['clicked_button']['#post'][$element['#name']] = $value; // Is this something we should do?
  }
  return $element;
}

/**
 * Returns HTML for the label for the empty value for options that are not required.
 *
 * The default theme will display N/A for a radio list and '- None -' for a select.
 *
 * @param $variables
 *   An associative array containing:
 *   - instance: An array representing the widget requesting the options.
 *   - option: An array representing the widget requesting the options.
 *
 */
function theme_select_or_other_none($variables) {
  $instance = $variables['instance'];

  $output = '';
  switch ($instance['widget']['type']) {
    case 'select_or_other_buttons':
      $output = t('N/A');
      break;

    case 'select_or_other':
    case 'select_or_other_sort':
      if (!empty($variables['option']) && $variables['option'] == 'option_none') {
        $output = t('- None -');
      }
      else {
        $output = t('- Select a value -');
      }
      break;
  }

  return $output;
}

/**
 * Helper function to check keys in multidimensional array.
 *
 * @param $needle
 *   The key.
 * @param $haystack
 *   The array to check.
 * @return
 *   Boolean indicating if the key is set.
 */
function select_or_other_multi_array_key_exists($needle, $haystack) {
  if (array_key_exists(html_entity_decode($needle, ENT_QUOTES), $haystack)) {
    return TRUE;
  }
  else {
    foreach ($haystack as $key => $value) {
      if (is_array($value) && select_or_other_multi_array_key_exists($needle, $value)) {
        return TRUE;
      }
    }
  }
  return FALSE;
}