<?php
// $Id: twitter.module,v 1.1 2007-01-23 17:05:50 walkah Exp $

define('TWITTER_URL', 'http://twitter.com/statuses/update.xml');

/**
 * Implementation of hook_user()
 */
function twitter_user($op, &$edit, &$account, $category = NULL) {
  switch ($op) {
    case 'form':
      $form['twitter'] = array(
        '#type' => 'fieldset',
        '#title' => t('Twitter settings'));
      $form['twitter']['twitter_user'] = array(
        '#type' => 'textfield',
        '#title' => t('Username'),
        '#default_value' => $edit['twitter_user'],
        '#description' => t('The username (email address) associated with your twitter.com account'));
      $form['twitter']['twitter_pass'] = array(
        '#type' => 'password',
        '#title' => t('Password'));
      $form['twitter']['twitter_text'] = array(
        '#type' => 'textfield',
        '#title' => t('Text format'),
        '#default_value' => $edit['twitter_text'],
        '#description' => t('Format of the text to submit. Use !title and !url for the post title and url respectively.'));
      return $form;
    case 'insert':
    case 'update':
      if (!empty($edit['twitter_user']) && !empty($edit['twitter_pass'])) {
        $edit['twitter_encrypted'] = base64_encode($edit['twitter_user'] .':'. $edit['twitter_pass']);
      }
      unset($edit['twitter_pass']);
  }
}

function twitter_nodeapi(&$node, $op) {
  switch ($op) {
    case 'insert':
      global $user;
      if ($node->status == 1) {
        twitter_post($node, $user);
      }
  }
}

/**
 * Implements the twitter posting API per:
 * http://twitter.com/help/api
 */
function twitter_post($node, $account) {
  if (empty($account->twitter_encrypted)) {
    return false;
  }

  $text = ($account->twitter_text) ? $account->twitter_text : 'New post: !title (!url)';
  $text = t($text, array('!title' => $node->title,
                         '!url' => url('node/' . $node->nid, NULL, NULL, TRUE)));
  
  $headers = array('Authorization' => 'Basic '. $account->twitter_encrypted,
                   'Content-type' => 'application/x-www-form-urlencoded');
  $data = 'status='. urlencode($text);

  $result = drupal_http_request(TWITTER_URL, $headers, 'POST', $data);
  drupal_set_message(t('Posted to twitter.com'));
}