<?php
/**
 * @file
 * Exposes Drupal actions for sending Twitter messages.
 */

/**
 * Implements hook_action_info().
 */
function twitter_actions_action_info() {
  return array(
    'twitter_actions_set_status_action' => array(
      'type' => 'system',
      'label' => t('Post a message to Twitter'),
      'configurable' => TRUE,
      'triggers' => array(
        'node_view',
        'node_insert',
        'node_update',
        'node_delete',
        'comment_view',
        'comment_insert',
        'comment_update',
        'comment_delete',
        'user_view',
        'user_insert',
        'user_update',
        'user_delete',
        'user_login',
        'cron',
      ),
    ),
  );
}

/**
 * Returns a form definition so the Twitter action can be configured.
 *
 * @param $context
 *   Default values (if we are editing an existing action instance).
 * @return
 *   Form definition.
 */
function twitter_actions_set_status_action_form($context) {
  $options = array();
  $results = db_query("SELECT screen_name FROM {twitter_account}");
  foreach ($results as $result) {
    $options[$result->screen_name] = $result->screen_name;
  }
  // Set default values for form.
  $form['screen_name'] = array(
    '#type' => 'select',
    '#title' => t('Twitter account name'),
    '#options'       => $options,
    '#default_value' => isset($context['screen_name']) ? $context['screen_name'] : '',
    '#required' => TRUE,
  );

  if (!count($options)) {
    $form['screen_name']['#description'] = t('You first need to add a Twitter account to one of ' .
                                             'your users with rights for posting to Twitter.');
  }

  $form['message'] = array(
    '#type' => 'textarea',
    '#title' => t('Message'),
    '#default_value' => isset($context['message']) ? $context['message'] : '',
    '#cols' => '80',
    '#rows' => '3',
    '#description' => t('The message that should be sent. You may include the following variables: ' .
                        '%site_name, %username, %node_url, %node_type, %title, %summary, %body, ' .
                        '%tinyurl. Not all variables will be available in all contexts.'),
    '#required' => TRUE,
  );

  return $form;
}

/**
 * Verifies if Oauth module has been setup and also checks the Twitter
 * authentication against the provided screen name.
 */
function twitter_actions_set_status_action_validate($form, $form_state) {
  if (!_twitter_use_oauth()) {
    form_set_error('screen_name', t('Oauth has not been setup yet. Please go to !link and follow steps.',
                                     array('!link' => l(t('Twitter settings'), 'admin/settings/twitter'))));
  }
}

/**
 * Submits the form and sets the twitter account pulling the data from the
 * twitter_account table.
 */
function twitter_actions_set_status_action_submit($form, $form_state) {
  $form_values = $form_state['values'];
  $twitter_uid = db_query("SELECT twitter_uid FROM {twitter_account} WHERE screen_name = :screen_name", array(':screen_name' => $form_values['screen_name']))->fetchField();
  // Process the HTML form to store configuration. The keyed array that
  // we return will be serialized to the database.
  $params = array(
    'twitter_uid' => $twitter_uid,
    'screen_name' => $form_values['screen_name'],
    'message' => $form_values['message'],
  );

  return $params;
}

/**
 * Implementation of a configurable Twitter actions.
 * @todo Implementation for language negotiation for the body and sumary. Also
 * need implementation for bodies with multiple values. Right now it is hard
 * coded and it will only get body and summary for 'und' language and only
 * the first value of the body field.
 * If the final message is over 140 chars, there is no feedback to the user.
 */
function twitter_actions_set_status_action($object, $context) {
  global $user;
  $variables['%site_name'] = variable_get('site_name', 'Drupal');
  // Seting variables array depending on action's group
  switch ($context['group']) {
    case 'node':
      $node = $context['node'];
      if (isset($node)) {
        $variables = array_merge($variables, array(
          '%uid' => $node->uid,
          '%username' => $node->name,
          '%node_url' => url('node/' . $node->nid, array('absolute' => TRUE)),
          '%node_type' => node_type_get_name($node),
          '%title' => $node->title,
          '%summary' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['summary'] : '',
          '%body' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['value'] : '',
          )
        );
      }
      break;

    case 'comment':
      $node = node_load($context['comment']->nid);
      if (isset($node)) {
        $variables = array_merge($variables, array(
          '%uid' => $context['comment']->uid,
          '%username' => $context['comment']->name,
          '%node_url' => url('node/' . $node->nid, array('absolute' => TRUE)),
          '%node_type' => node_type_get_name($node),
          '%title' => $node->title,
          '%summary' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['summary'] : '',
          '%body' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['value'] : '',
          )
        );
      }
      break;

    case 'user':
      $variables['%username'] = $context['user']->name;
      break;

    case 'cron':
      break;

    default:
      // We are being called directly.
      $node = $object;
      if (isset($node)  && is_object($node)) {
        $variables = array_merge($variables, array(
          '%uid' => $node->uid,
          '%username' => $node->name,
          '%node_url' => url('node/' . $node->nid, array('absolute' => TRUE)),
          '%node_type' => node_type_get_name($node),
          '%title' => $node->title,
          '%summary' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['summary'] : '',
          '%body' => isset($node->body['und'][0]['value']) ? $node->body['und'][0]['value'] : '',
          )
        );
      }
  }

  // Only make a tinyurl if it was asked for.
  if (strstr($context['message'], '%tinyurl') !== FALSE) {
    $variables = array_merge($variables, array(
      '%tinyurl' => twitter_shorten_url(url('node/' . $node->nid, array('absolute' => TRUE))),
    ));
  }

  $message = strtr($context['message'], $variables);
  module_load_include('inc', 'twitter');
  $twitter_account = twitter_account_load($context['twitter_uid']);
  twitter_set_status($twitter_account, $message);
}