<?php
/**
 * Automatic AJAX forms validation, preview, and submission
 *
 * @see http://drupal.org/project/ajax
 * @see irc://freenode.net/#drupy
 * @depends Drupal 6
 * @author brendoncrawford
 * @note This file uses a 79 character width limit.
 * @note Available hooks are:
 *   hook_ajax_validate_fail
 *   hook_ajax_validate_cleanup
 *   hook_ajax_types
 *   hook_ajax_alter
 *
 */

/**
 * hook_menu
 *
 * @return Assoc
 */
function ajax_menu() {
  $items['admin/settings/ajax'] = array(
    'title' => t('Ajax Forms Settings'),
    'description' => t('Controls which forms should use AJAX submissions.'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ajax_admin'),
    'access arguments' => array('access administration pages'),
    'type' => MENU_NORMAL_ITEM,
  );
  return $items;
}

/**
 * Get content types
 *
 * @return Assoc
 */
function ajax_get_types() {
  $types = array_merge(
    ajax_types_node(),
    ajax_types_user());
  ajax_invoke('ajax_types', $types);
  return $types;
}

/**
 * Get node types
 *
 * @return Assoc
 */
function ajax_types_node() {
  $out = array();
  $types = node_get_types();
  foreach ($types as $k => $v) {
    $out[$k . '_node_form'] = ucwords('Content Type: ' . $v->name);
  }
  return $out;
}

/**
 * Get module types.
 * This function currently unused.
 *
 * @return Assoc
 */
function ajax_types_module() {
  $out = array();
  $funcs = get_defined_functions();
  foreach ($funcs['user'] as $f) {
    if (preg_match("/^([a-zA-Z][a-zA-Z0-9_]*?)_submit$/", $f, $func_name)) {
      $out[$func_name[1]] = ucwords(str_replace('_', ' ', $func_name[1]));
    }
  }
  return $out;
}

/**
 * Get other default types
 *
 * @return Assoc
 */
function ajax_types_user() {
  return array(
    'user_login' => t('User Login'),
    'user_edit' => t('User Edit'),
    'user_register' => t('User Register')
  );
}

/**
 * Display admin form
 *
 * @return Assoc
 */
function ajax_admin() {
  $form = array(
    'container_default' => array(
      '#type' => 'fieldset',
      '#title' => t('Default Forms'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      'ajax_types_default' => array(
        '#type' => 'select',
        '#multiple' => TRUE,
        '#options' => ajax_get_types(),
        '#default_value' => variable_get('ajax_types_default', array()),
        '#size' => 20,
        '#description' => t(
          "Select the default forms you wish to use AJAX submissions.")
      )
    ),
    'container_custom' => array(
      '#type' => 'fieldset',
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#title' => t('Custom Forms (Advanced)'),
      'ajax_types_custom' => array(
        '#type' => 'textarea',
        '#default_value' => variable_get('ajax_types_custom', ''),
        '#description' => t(
          'Enter the form IDs of the custom forms you wish to ' .
          'use AJAX Submissions. Enter one ID per line. Only alpha-numeric ' .
          'characters should be used. ')
      )
    )
  );
  return system_settings_form($form);
}

/**
 * hook_init
 *
 * @return Bool
 */
function ajax_init() {
  drupal_add_js(drupal_get_path('module', 'ajax') .
    '/Ajax.js', 'module');
  return TRUE;
}

/**
 * Checks if form is a specified type
 *
 * @param $form Assoc
 * @param $form_id String
 * @return Bool
 */
function ajax_is_type($form, $form_id) {
  // Module defined forms
  if (array_key_exists('#ajax', $form) && $form['#ajax']) {
    return TRUE;
  }
  // User defined forms
  else {
    $exists = array_key_exists($form_id,
      variable_get('ajax_types_default', array()));
    if ($exists) {
      return TRUE;
    }
    else {
      $custom = variable_get('ajax_types_custom', FALSE);
      if ($custom !== FALSE) {
        $parts = preg_split("/[\r\n]+/", $custom, -1, PREG_SPLIT_NO_EMPTY);
        if ($parts) {
          foreach ($parts as $v) {
            if (trim($v) === $form_id) {
              return TRUE;
            }
          }
        }
      }
      return FALSE;
    }
  }
}

/**
 * hook_form_alter
 *
 * @param $form Assoc
 * @param $form_state Assoc
 * @param $form_id String
 * @return Bool
 */
function ajax_form_alter(&$form, $form_state, $form_id) {
  //watchdog('AJAX Forms', 'Form ID: %form_id', array('%form_id'=>$form_id));
  if (ajax_is_type($form, $form_id)) {
    $found = FALSE;
    ajax_invoke('ajax_alter', $form, $form_id);
    ajax_validator_set($form);
    ajax_submitter_find($form, $found);
    ajax_submitter_set($form, $found);
  }
  return TRUE;
}

/**
 * Gets internal path from actual url path
 *
 * @param $val String
 * @return String
 */
function ajax_drupal_path($val) {
  $b = base_path();
  $bs = sizeof($b);
  if (substr($val, 0, $bs) === $b) {
    return substr($val, $bs);
  }
  else {
    return $val;
  }
}

/**
 * Collects path info
 *
 * @param $val String
 * @return Assoc
 */
function ajax_path_info($val) {
  $out = array(
    'path' => NULL,
    'query' => array(),
    'fragment' => NULL
  );
  $u = parse_url($val);
  if (array_key_exists('query', $u)) {
    parse_str($u, $out['query']);
  }
  if (array_key_exists('path', $u)) {
    $out['path'] = $u['path'];
  }
  if (array_key_exists('fragment', $u)) {
    $out['fragment'] = $u['fragment'];
  }
  return $out;
}

/**
 * Sets the validator
 *
 * @param $form Assoc
 * @return Bool
 */
function ajax_validator_set(&$form) {
  $form['#validate'][] = 'ajax_validator';
  return TRUE;
}

/**
 * Sets the submitter
 *
 * @param $form Assoc
 * @param $found Bool
 * @return Bool
 */
function ajax_submitter_set(&$form, $found) {
  if (!$found) {
    $form['#submit'][] = 'ajax_submitter';
  }
  return TRUE;
}

/**
 * Finds the submitter
 *
 * @param $form Assoc
 * @param $found Bool
 * @return Bool
 */
function ajax_submitter_find(&$form, &$found) {
  foreach ($form as $form_key => $form_val) {
    if (is_array($form[$form_key])) {
      //submit or preview button
      if (
          (array_key_exists('#type', $form[$form_key]) &&
          ($form[$form_key]['#type'] === 'submit' ||
          $form[$form_key]['#type'] === 'button')) &&
          ($form_key === 'submit' || $form_key === 'preview')) {
        $form[$form_key]['#attributes'] =
          array('onclick' => 'return Ajax.go(this);');
        if (array_key_exists('#submit', $form[$form_key]) &&
            !empty($form[$form_key]['#submit'])) {
          $form[$form_key]['#submit'][] = 'ajax_submitter';
          $found = TRUE;
        }
      }
      //nested
      else {
        ajax_submitter_find($form[$form_key], $found);
      }
    }
  }
  return TRUE;
}

/**
 * Gets redirect
 * Sometimes the redirect can be an array in the form of
 *   0 => path
 *   1 => query
 *   2 => fragment
 *
 * @param $redirect String|Array
 * @return String
 */
function ajax_get_redirect($redirect) {
  //watchdog('AJAX Forms', 'Redirect: !redirect',
  //  array('!redirect'=>gettype($redirect[1])));
  $args = array();
  $args['absolute'] = TRUE;
  if (is_array($redirect)) {
    if ($redirect[1] !== NULL) {
      $args['query'] = $redirect[1];
    }
    if ($redirect[2] !== NULL) {
      $args['fragment'] = $redirect[2];
    }
    $path = $redirect[0];
  }
  else {
    $path = $redirect;
  }
  return url($path, $args);
}

/**
 * Submission handler callback
 *
 * @param $form Assoc
 * @param $form_state Assoc
 * @return Bool
 */
function ajax_submitter(&$form, &$form_state) {
  $data = array();
  // Node Preview
  if (array_key_exists('node_preview', $form_state) &&
      $form_state['node_preview'] !== NULL) {
    $data['preview'] = $form_state['node_preview'];
  }
  // Go to redirection page
  if (array_key_exists('redirect', $form_state) &&
      $form_state['redirect'] !== NULL) {
    $data['redirect'] = $form_state['redirect'];
  }
  // Display messages internally without redirect
  else {
    $messages = drupal_get_messages(NULL, TRUE);
    if (array_key_exists('status', $messages)) {
      $data['messages_status'] = $messages['status'];
    }
    if (array_key_exists('warning', $messages)) {
      $data['messages_warning'] = $messages['warning'];
    }
  }
  $out = ajax_build($data);
  ajax_out($out);
  return TRUE;
}

/**
 * Invokes hooks
 *
 * @param unknown_type $view_name
 * @param unknown_type $display_id
 * @param unknown_type $out
 * @return unknown
 */
function ajax_invoke($hook, &$p1=NULL, &$p2=NULL, &$p3=NULL, &$p4=NULL) {
  foreach (module_implements($hook) as $name) {
    $function = $name . '_' . $hook;
    $result = $function($p1, $p2, $p3, $p4);
  }
  return TRUE;
}

/**
 * Validation handler callback
 *
 * @param $form Assoc
 * @param $form_state Assoc
 * @return Bool
 */
function ajax_validator(&$form, &$form_state) {
  if (array_key_exists('ajax', $_REQUEST)) {
    drupal_get_messages(NULL, TRUE);
    $data = ajax_build(array(
      'messages_error' => form_get_errors()
    ));
    // FAIL
    if (!$data['status']) {
      ajax_invoke('ajax_validate_fail', $form, $form_state, $data);
      ajax_out($data);
    }
    // PASS
    else {
      $pass = TRUE;
      ajax_invoke('ajax_validate_pass', $form, $form_state, $data, $pass);
      if (!$pass) {
        ajax_out($data);
      }
    }
  }
  return TRUE;
}

/**
 * Outputs data
 *
 * @param $data String
 * @return Exit
 */
function ajax_out($data) {
  header('HTTP/1.1 200 OK', TRUE);
  header("Content-Type: application/json; charset=UTF-8", TRUE);
  print drupal_to_js($data);
  exit;
}

/**
 * Gets a clean element id
 * taken from form_clean_id
 *
 * @param $field_id String
 * @return String
 */
function ajax_clean_id($field_id) {
  return str_replace(array('][', '_', ' '), '-', $field_id);
}

/**
 * Builds the output object
 *
 * @param $data Assoc
 * @return Assoc
 */
function ajax_build($data) {
  $out = array(
    'status' => true,
    'updaters' => array(),
    'debug' => array(),
    'messages_error' => array(),
    'messages_status' => array(),
    'messages_warning' => array(),
    'redirect' => NULL,
    'preview' => NULL
  );
  // MESSAGE:ERROR
  if (array_key_exists('messages_error', $data) &&
      $data['messages_error'] !== NULL) {
    $out['status'] = FALSE;
    foreach ($data['messages_error'] as $k => $v) {
      $out['messages_error'][] = array(
        'id' => ajax_clean_id("edit-" . $k),
        'value' => $v
      );
    }
  }
  // MESSAGE:STATUS
  if (array_key_exists('messages_status', $data) &&
      $data['messages_status'] !== NULL) {
    foreach ($data['messages_status'] as $k => $v) {
      $out['messages_status'][] = array(
        'id' => (int)$k,
        'value' => $v
      );
    }
  }
  // MESSAGE:WARNING
  if (array_key_exists('messages_warning', $data) &&
      $data['messages_warning'] !== null) {
    foreach ($data['messages_warning'] as $k => $v) {
      $out['messages_warning'][] = array(
        'id' => (int)$k,
        'value' => $v
      );
    }
  }
  // Redirect: Destination Parameter
  if (array_key_exists('destination', $_GET)) {
    $out['redirect'] = ajax_get_redirect($_GET['destination']);
  }
  // Redirect: Explicit
  elseif (array_key_exists('redirect', $data) && $data['redirect'] !== NULL) {
    $out['redirect'] = ajax_get_redirect($data['redirect']);
  }
  // Preview
  if (array_key_exists('preview', $data) && $data['preview'] !== NULL) {
    $out['preview'] = rawurlencode($data['preview']);
  }
  // Debug
  if (array_key_exists('debug', $data) && $data['debug'] !== NULL) {
    $out['debug'] = $data['debug'];
  }
  return $out;
}