<?php

/**
 * @file
 *   Localization client. Provides on-page translation editing.
 */

/**
 * Number of strings for paging on translation pages.
 */
define('L10N_CLIENT_STRINGS', 100);

/**
 * Implement hook_menu().
 */
function l10n_client_menu() {
  $items = array();

  // AJAX callback path for strings.
  $items['l10n_client/save'] = array(
    'title' => 'Save string',
    'page callback' => 'l10n_client_save_string',
    'access callback' => 'l10n_client_access',
    'type' => MENU_CALLBACK,
  );
  // Helper pages to group all translated/untranslated strings.
  $items['locale'] = array(
    'title' => 'Translate strings',
    'page callback' => 'l10n_client_translate_page',
    'access callback' => 'l10n_client_access',
  );
  $items['locale/untranslated'] = array(
    'title' => 'Untranslated',
    'page arguments' => array('untranslated'),
    'access callback' => 'l10n_client_access',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['locale/translated'] = array(
    'title' => 'Translated',
    'page arguments' => array('translated'),
    'access callback' => 'l10n_client_access',
    'type' => MENU_LOCAL_TASK,
    'weight' => 10,
  );

  $items['admin/config/regional/translate/client'] = array(
    'title' => 'Client',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('l10n_client_settings_form'),
    'access arguments' => array('administer languages'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'l10n_client.admin.inc',
    'weight' => 40,
  );
  return $items;
}

/**
 * Implement hook_permission().
 */
function l10n_client_permission() {
  return array(
    'use on-page translation' => array(
      'title' => t('Use on-page translation'),
      'description' => t('Makes it possible to translate the Drupal interface on-page.'),
    ),
    'submit translations to localization server' => array(
      'title' => t('Submit translations to localization server'),
      'description' => t('Allows users to submit translations to a remote localization server.'),
    ),
  );
}

/**
 * Implement hook_theme().
 */
function l10n_client_theme($existing, $type, $theme, $path) {
  return array(
    'l10n_client_message' => array(
      'variables' => array('message' => '', 'level' => WATCHDOG_ERROR),
    ),
  );
}

/**
 * Implement hook_init().
 */
function l10n_client_init() {
  global $conf, $language;

  if (l10n_client_access()) {
    // Turn off the short string cache *in this request*, so we will
    // have an accurate picture of strings used to assemble the page.
    $conf['locale_cache_strings'] = 0;
    // Reset locale cache. If any hook_init() implementation was invoked before
    // this point, that would normally result in all strings loaded into memory.
    // That would go against our goal of displaying only strings used on the page
    // and would hang browsers. Drops any string used for the page before this point.
    drupal_static_reset('locale');
    drupal_add_css(drupal_get_path('module', 'l10n_client') .'/l10n_client.css');
    drupal_add_js(drupal_get_path('module', 'l10n_client') .'/jquery.hotkeys.js');
    drupal_add_js('misc/jquery.cookie.js');
    drupal_add_js(drupal_get_path('module', 'l10n_client') .'/l10n_client.js');
    // We use textareas to be able to edit long text, which need resizing.
    drupal_add_js('misc/textarea.js');
  }
}

/**
 * Detects whether a user can access l10n_client.
 */
function l10n_client_access($account = NULL) {
  if (!isset($account)) {
    global $user;
    $account = $user;
  }
  $user_enabled = empty($account->data['l10n_client_disabled']);
  $user_access = user_access('use on-page translation', $account);
  $paths = variable_get('l10n_client_disabled_paths', '');
  $paths_disabled = !empty($paths) && drupal_match_path(current_path(), $paths);
  return $user_access && $user_enabled && !$paths_disabled;
}

/**
 * Menu callback. Translation pages.
 *
 * These pages just list strings so they can be added to the string list for
 * translation below the page. This can be considered a hack, since we could
 * just implement the same UI on the page, and do away with these artifical
 * listings, but the current UI works, so we just reuse it this way.
 *
 * This includes custom textgroup support that can be used manually or
 * by other modules.
 *
 * @param $display_translated
 *   Boolean indicating whether translated or untranslated strings are displayed.
 * @param $textgroup
 *   Internal name of textgroup to use.
 * @param $allow_translation
 *   Boolean indicating whether translation of strings via the l10n_client UI is allowed.
 */
function l10n_client_translate_page($display_translated = FALSE, $textgroup = 'default', $allow_translation = TRUE) {
  global $language;

  $table = array();

  $query = db_select('locales_source', 's')->extend('PagerDefault');
  $query->leftJoin('locales_target', 't', "s.lid = t.lid AND t.language = :lang", array(':lang' => $language->language));
  $query->fields('s', array('source'))
    ->fields('t', array('translation', 'language'))
    ->orderBy('s.source');

  if ($display_translated) {
    $header = array(t('Source string'), t('Translation'));
    $query->condition('t.translation', '', '!=');
  }
  else {
    $header = array(t('Source string'));
    $query->isNull('t.lid');
  }
  if (!empty($textgroup)) {
    $query->condition('s.textgroup', $textgroup);
  }

  // For the 'default' textgroup and English language we don't allow translation.
  $allow_translation = (($textgroup == 'default') && ($language->language == 'en')) ? FALSE : $allow_translation;

  $result = $query
    ->limit(L10N_CLIENT_STRINGS)
    ->execute();

  foreach ($result as $data) {
    if ($display_translated) {
      $table[] = array(check_plain($data->source), check_plain($data->translation));
      if ($allow_translation) {
        l10_client_add_string_to_page($data->source, $data->translation, $textgroup);
      }
    }
    else {
      $table[] = array(check_plain($data->source));
      if ($allow_translation) {
        l10_client_add_string_to_page($data->source, TRUE, $textgroup);
      }
    }
  }
  $pager = theme('pager');
  return $pager . theme('table', array('header' => $header, 'rows' => $table, 'empty' => t('No strings found to translate.'))) . $pager;
}

/**
 * Implement hook_page_alter().
 *
 * Output a form to the page and a list of strings used to build the page in
 * JSON form.
 */
function l10n_client_page_alter(&$page) {
  global $conf, $language;

  // Check permission and get all strings used on the page.
  if (l10n_client_access() && ($page_strings = _l10n_client_page_strings())) {
    // If we have strings for the page language, restructure the data.
    $l10n_strings = array();
    foreach ($page_strings as $textgroup => $group_strings) {
      foreach ($group_strings as $context => $context_strings) {
        foreach ($context_strings as $string => $translation) {
          $l10n_strings[] = array($string, $translation, $textgroup, $context);
        }
      }
    }
    array_multisort($l10n_strings);
    // Include string selector on page.
    $string_list = _l10n_client_string_list($l10n_strings);
    // Include editing form on page.
    $form = drupal_get_form('l10n_client_form', $l10n_strings);
    $l10n_form = drupal_render($form);
    // Include search form on page.
    $form = drupal_get_form('l10n_client_search_form');
    $l10n_search = drupal_render($form);
    // Generate HTML wrapper with strings data.
    $l10n_dom = _l10n_client_dom_strings($l10n_strings);

    // UI Labels
    $string_label = '<h2>'. t('Page Text') .'</h2>';
    $source_label = '<h2>'. t('Source') .'</h2>';
    $translation_label = '<h2>'. t('Translation to %language', array('%language' => $language->native)) .'</h2>';
    $toggle_label = t('Translate Text');

    $output = "
      <div id='l10n-client' class='l10n-client-minimized'>
        <div class='labels'>
          <span class='toggle'>$toggle_label</span>
          <div class='label strings'>$string_label</div>
          <div class='label source'>$source_label</div>
          <div class='label translation'>$translation_label</div>
        </div>
        <div id='l10n-client-string-select'>
          $string_list
          $l10n_search
        </div>
        <div id='l10n-client-string-editor'>
          <div class='source'>
            <div class='source-text'></div>
            <div class='context'></div>
          </div>
          <div class='translation'>
            $l10n_form
          </div>
        </div>
      </div>
      $l10n_dom
    ";

    $page['page_bottom']['l10n_client'] = array(
      '#type' => 'markup',
      '#markup' => $output,
    );
  }
}

/**
 * Adds a string to the list onto the l10n_client UI on this page.
 *
 * @param $source
 *   Source string or NULL if geting the list of strings specified.
 * @param $translation
 *   Translation string. TRUE if untranslated.
 * @param $textgroup
 *   Text group the string belongs to
 */
function l10_client_add_string_to_page($source = NULL, $translation = NULL, $textgroup = 'default', $context = '') {
  static $strings = array();

  if (isset($source)) {
    $strings[$textgroup][$context][$source] = $translation;
  }
  else {
    return $strings;
  }
}

/**
 * Get the strings to translate for this page.
 *
 * These will be:
 *   - The ones added through l10n_client_add_string_to_page() by this or other modules.
 *   - The strings stored by the locale function (not for for this module's own pages).
 */
function _l10n_client_page_strings() {
  global $language;

  // Get the page strings stored by this or other modules.
  $strings = l10_client_add_string_to_page();

  // If this is not the module's translation page, merge all strings used on the page.
  if (arg(0) != 'locale' && is_array($locale = locale()) && isset($locale[$language->language])) {
    // Get the page strings stored by this or other modules.
    $strings += array('default' => array());
    foreach ($locale[$language->language] as $context => $context_strings) {
      $strings['default'] += array($context => array());
      $strings['default'][$context] = array_merge($strings['default'][$context], $context_strings);
    }


    // Also select and add other strings for this path. Other users may have run
    // into these strings for the same page. This might be useful in some cases
    // but will not work reliably in all cases, since strings might have been
    // found on completely different paths first, or on a slightly different
    // path.
    $result = db_query("SELECT s.source, t.translation, s.textgroup, s.context FROM {locales_source} s LEFT JOIN {locales_target} t ON s.lid = t.lid AND t.language = :language WHERE s.location = :location", array(':language' => $language->language, ':location' => request_uri()));
    foreach ($result as $data) {
      if (!array_key_exists($data->source, $strings[$data->textgroup])) {
        $strings[$data->textgroup][$data->context][$data->source] = (empty($data->translation) ? TRUE : $data->translation);
      }
    }
  }

  return $strings;
}

/**
 * Helper function for the string list DOM tree
 */
function _l10n_client_dom_strings($strings) {
  $output = '';
  foreach ($strings as $values) {
    list ($source, $target, $textgroup, $context) = $values;
    $source = $source === TRUE ? '' : htmlspecialchars($source, ENT_NOQUOTES, 'UTF-8');
    $target = $target === TRUE ? '' : htmlspecialchars($target, ENT_NOQUOTES, 'UTF-8');
    $context = htmlspecialchars($context, ENT_NOQUOTES, 'UTF-8');
    $output .= "<div><span class='source'>$source</span><span class='target'>$target</span><span class='textgroup'>$textgroup</span><span class='context'>$context</span></div>";
  }
  return "<div id='l10n-client-data'>$output</div>";
}

/**
 * String selection has been moved to a jquery-based list.
 * Todo: make this a themeable function.
 */
function _l10n_client_string_list($strings) {
  // Build a list of short string excerpts for a selectable list.
  foreach ($strings as $values) {
    // Add a class to help identify translated strings
    if ($values[1] === TRUE) {
      $str_class = 'untranslated';
    }
    else {
      $str_class = 'translated';
    }
    // TRUE means we don't have translation, so we use the original string,
    // so we always have the string displayed on the page in the dropdown.
    $original = $values[1] === TRUE ? $values[0] : $values[1];

    // Remove HTML tags for display.
    $string = strip_tags($original);

    if (empty($string)) {
      // Edge case where the whole string was HTML tags. For the
      // user to be able to select anything, we need to show part
      // of the HTML tags. Truncate first, so we do not truncate in
      // the middle of an already escaped HTML tag, thus possibly
      // breaking the page.
      $string = htmlspecialchars(truncate_utf8($original, 78, TRUE, TRUE), ENT_NOQUOTES, 'UTF-8');
    }
    else {
      // Truncate and add ellipsis if too long.
      $string = truncate_utf8($string, 78, TRUE, TRUE);
    }

    $select_list[] = "<li class='$str_class'>$string</li>";
  }
  $output = implode("\n", $select_list);
  return "<ul class='string-list'>$output</ul>";
}

/**
 * String editing form. Source & selection moved to UI components outside the form.
 * Backed with jquery magic on the client.
 *
 * @todo
 *   This form has nothing to do with different plural versions yet.
 */
function l10n_client_form($form_id, $strings) {
  global $language;

  // Selector and editing form.
  $form = array();
  $form['#action'] = url('l10n_client/save');

  $form['target'] = array(
    '#title' => t('Translation to %language', array('%language' => $language->native)),
    '#title_display' => 'invisible',
    '#type' => 'textarea',
    '#resizable' => false,
    '#rows' => 6,
    '#attributes' => array('class' => array('translation-target')),
  );
  $form['save'] = array(
    '#value' => t('Save translation'),
    '#type' => 'submit',
    '#attributes' => array('class' => array('edit-save')),
  );
  $form['textgroup'] = array(
    '#type' => 'hidden',
    '#value' => 'default',
    '#attributes' => array('class' => array('source-textgroup')),
  );
  $form['context'] = array(
    '#type' => 'hidden',
    '#value' => 'default',
    '#attributes' => array('class' => array('source-context')),
  );
  $form['copy'] = array(
    '#type' => 'button',
    '#id' => 'l10n-client-edit-copy',
    '#attributes' => array('class' => array('edit-copy')),
    '#value' => t('Copy source'),
  );
  $form['clear'] = array(
    '#type' => 'button',
    '#id' => 'l10n-client-edit-clear',
    '#attributes' => array('class' => array('edit-clear')),
    '#value' => t('Clear'),
  );

  return $form;
}

/**
 * Search form for string list
 */
function l10n_client_search_form() {
  global $language;
  // Selector and editing form.
  $form = array();
  $form['search'] = array(
    '#title' => t('Search'),
    '#title_display' => 'invisible',
    '#type' => 'textfield',
    '#attributes' => array('class' => array('string-search')),
  );
  $form['clear-button'] = array(
    '#type' => 'button',
    '#id' => 'l10n-client-search-filter-clear',
    '#value' => t('X'),
  );
  return $form;
}

/**
 * Menu callback. Saves a string translation coming as POST data.
 */
function l10n_client_save_string() {
  global $user, $language;

  if (l10n_client_access()) {
    if (isset($_POST['source']) && isset($_POST['target']) && !empty($_POST['textgroup']) && !empty($_POST['form_token']) && drupal_valid_token($_POST['form_token'], 'l10n_client_form')) {
      // Ensure we have this source string before we attempt to save it.
      $lid = db_query("SELECT lid FROM {locales_source} WHERE source = :source AND context = :context AND textgroup = :textgroup", array(':source' => $_POST['source'], ':context' => $_POST['context'], ':textgroup' => $_POST['textgroup']))->fetchField();

      if (!empty($lid)) {
        include_once 'includes/locale.inc';
        $report = array('skips' => 0, 'additions' => 0, 'updates' => 0, 'deletes' => 0);
        _locale_import_one_string_db($report, $language->language, $_POST['context'], $_POST['source'], $_POST['target'], $_POST['textgroup'], NULL, LOCALE_IMPORT_OVERWRITE);
        cache_clear_all('locale:', 'cache', TRUE);
        _locale_invalidate_js($language->language);

        if (!empty($report['skips'])) {
          $message = theme('l10n_client_message', array('message' => t('Not saved locally due to invalid HTML content.')));
        }
        elseif (!empty($report['additions']) || !empty($report['updates'])) {
          $message = theme('l10n_client_message', array('message' => t('Translation saved locally.'), 'level' => WATCHDOG_INFO));
        }
        elseif (!empty($report['deletes'])) {
          $message = theme('l10n_client_message', array('message' => t('Translation successfuly removed locally.'), 'level' => WATCHDOG_INFO));
        }
        else {
          $message = theme('l10n_client_message', array('message' => t('Unknown error while saving translation locally.')));
        }

        // Submit to remote server if enabled.
        if (empty($report['skips']) && variable_get('l10n_client_use_server', FALSE) && user_access('submit translations to localization server') && ($_POST['textgroup'] == 'default')) {
          if (!empty($user->data['l10n_client_key'])) {
            $remote_result = l10n_client_submit_translation($language->language, $_POST['source'], $_POST['target'], $user->data['l10n_client_key'], l10n_client_user_token($user));
            $message .= theme('l10n_client_message', array('message' => $remote_result[1], 'level' => $remote_result[0] ? WATCHDOG_INFO : WATCHDOG_ERROR));
          }
          else {
            $server_url = variable_get('l10n_client_server', 'http://localize.drupal.org');
            $user_edit_url = url('user/'. $user->uid .'/edit', array('absolute' => TRUE));
            $message .= theme('l10n_client_message', array('message' => t('You could share your work with !l10n_server if you set your API key at !user_link.', array('!l10n_server' => l($server_url, $server_url), '!user_link' => l($user_edit_url, 'user/'. $user->uid .'/edit'))), 'level' => WATCHDOG_WARNING));
          }
        }
      }
      else {
        $message = theme('l10n_client_message', array('message' => t('Not saved due to source string missing.')));
      }
    }
    else {
      $message = theme('l10n_client_message', array('message' => t('Not saved due to missing form values.')));
    }
  }
  else {
    $message = theme('l10n_client_message', array('message' => t('Not saved due to insufficient permissions.')));
  }
  drupal_json_output($message);
  exit;
}

/**
 * Theme function to wrap l10n_client messages in proper markup.
 */
function theme_l10n_client_message($vars) {
  switch ($vars['level']) {
    case WATCHDOG_INFO:
      return '<div class="l10n-client-feedback message-info">'. $vars['message'] .'</div>';
      break;
    case WATCHDOG_WARNING:
      return '<div class="l10n-client-feedback message-warning">'. $vars['message'] .'</div>';
      break;
    case WATCHDOG_ERROR:
      return '<div class="l10n-client-feedback message-error">'. $vars['message'] .'</div>';
      break;
  }
}

// -----------------------------------------------------------------------------

/**
 * Implement hook_user_form().
 *
 * Set up API key for localization server.
 */
function l10n_client_form_user_profile_form_alter(&$form, &$form_state) {
  if ($form['#user_category'] == 'account') {
    $items = array();
    $account = $form['#user'];
    $use_server = variable_get('l10n_client_use_server', FALSE);
    $server_root = variable_get('l10n_client_server', 'http://localize.drupal.org');

    if ($use_server && user_access('submit translations to localization server', $account)) {
      // Build link to retrieve user key.
      $server_link = $server_root . '?q=translate/remote/userkey/' . l10n_client_user_token($account);
      $items['l10n_client_key'] = array(
        '#type' => 'textfield',
        '#title' => t('Your API key for @server', array('@server' => $server_root)),
        '#default_value' => !empty($account->data['l10n_client_key']) ? $account->data['l10n_client_key'] : '',
        '#description' => t('This is a unique key that will allow you to send translations to the remote server. To get your API key go to !server-link.', array('!server-link' => l($server_link, $server_link))),
      );
    }
    if (user_access('use on-page translation', $account)) {
      // Add an item to let the user disable the on-page tool.
      $items['l10n_client_disabled'] = array(
        '#type' => 'checkbox',
        '#title' => t('Hide on-page translation from you'),
        '#default_value' => !empty($account->data['l10n_client_disabled']),
      );
    }

    if (!empty($items)) {
      // Add items in a fieldset wrapper if any items available.
      $form['l10n_client'] = array(
        '#type' => 'fieldset',
        '#title' => t('Localization client'),
        '#weight' => 1,
        'items' => $items,
      );
    }
  }
}

/**
 * Implement hook_user_presave().
 *
 * Save the l10n_client_key value in the user object.
 */
function l10n_client_user_presave(&$edit, $account, $category) {
  if (isset($edit['l10n_client_key'])) {
    $edit['data']['l10n_client_key'] = trim($edit['l10n_client_key']);
  }
  $edit['data']['l10n_client_disabled'] = !empty($edit['l10n_client_disabled']);
}

/**
 * Get user based semi unique token. This will ensure user keys are unique for each client.
 */
function l10n_client_user_token($account = NULL) {
  global $user;
  $account = isset($account) ? $account : $user;
  return md5('l10n_client'. $account->uid . drupal_get_private_key());
}

/**
 * Submit translation to the server.
 */
function l10n_client_submit_translation($langcode, $source, $translation, $user_key, $user_token) {
  $server_uid = current(explode(':', $user_key));
  $signature = md5($user_key . $langcode . $source . $translation . $user_token);
  $server_url = variable_get('l10n_client_server', 'http://localize.drupal.org');

  $response = xmlrpc(
    $server_url .'/xmlrpc.php',
    array('l10n.submit.translation' => array(
      $langcode,
      $source,
      $translation,
      (int)$server_uid,
      $user_token,
      $signature
    ))
  );

  if (!empty($response) && isset($response['status'])) {
    if ($response['status']) {
      $message = t('Translation sent and accepted by @server.', array('@server' => $server_url));
      watchdog('l10n_client', 'Translation sent and accepted by @server.', array('@server' => $server_url));
    } else {
      $message = t('Translation rejected by @server. Reason: %reason', array('%reason' => $response['reason'], '@server' => $server_url));
      watchdog('l10n_client', 'Translation rejected by @server. Reason: %reason', array('%reason' => $response['reason'], '@server' => $server_url), WATCHDOG_WARNING);
    }
    return array($response['status'], $message);
  }
  else {
    $message = t('The connection with @server failed with the following error: %error_code: %error_message.', array('%error_code' => xmlrpc_errno(), '%error_message' => xmlrpc_error_msg(), '@server' => $server_url));
    watchdog('l10n_client', 'The connection with @server failed with the following error: %error_code: %error_message.', array('%error_code' => xmlrpc_errno(), '%error_message' => xmlrpc_error_msg(), '@server' => $server_url), WATCHDOG_ERROR);
    return array(FALSE, $message);
  }
}

/**
 * Implements hook_field_extra_fields().
 */
function l10n_client_field_extra_fields() {
  $extra['user']['user']['form']['l10nclient'] = array(
    'label' => 'Localization client',
    'description' => t('On-page localization form element.'),
    'weight' => 10,
  );
  return $extra;
}