<?php
// $Id: sharethis.module,v 1.1.2.13 2009/06/06 17:40:54 robloach Exp $

/**
 * @file
 * Provides the ShareThis service.
 */

/**
 * Implementation of hook_help().
 */
function sharethis_help($path, $arg) {
  switch ($path) {
    case 'admin/help#sharethis':
      $output = '<p>'. t('Provides functionality to interface with the <a href="@sharethis">ShareThis</a> web service to share data across different social networks.', array('@sharethis' => 'http://sharethis.com')) .'</p>';
      $output .= '<p>'. theme('sharethis', t('Drupal ShareThis Module'), 'http://drupal.org/project/sharethis') .'</p>';
      return $output;
    case 'admin/settings/sharethis':
      return '<p>'. t('Below provides the settings for interfacing with the <a href="@sharethis">ShareThis</a> web service to share data across different social networks.', array('@sharethis' => 'http://sharethis.com')) .'</p>';
  }
}

/**
 * Implementation of hook_perm().
 */
function sharethis_perm() {
  return array('administer share', 'use share this');
}

/**
 * Implementation of hook_menu().
 */
function sharethis_menu() {
  $items = array();
  $items['admin/settings/sharethis'] = array(
    'title' => t('ShareThis'),
    'description' => t('Administer settings related to the ShareThis web service.'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array('sharethis_admin_settings'),
    'access arguments' => array('administer share'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'sharethis.admin.inc',
  );
  return $items;
}

/**
 * Implementation of hook_nodeapi().
 */
function sharethis_nodeapi(&$node, $op, $teaser, $page) {
  switch ($op) {
    case 'view':
      if (user_access('use share this')) {
        if (!$teaser || variable_get('sharethis_teaser', 1)) {
          if (variable_get('sharethis_sharethis_this_where', 'links') == 'nodes') {
            if (in_array($node->type, variable_get('sharethis_sharethis_this_node_types', array()), TRUE)) {
              // Create the ShareThis element.
              $sharethis = theme('sharethis', $node->title, url('node/'. $node->nid, array('absolute' => TRUE)));
              $node->content['sharethis_sharethis_this'] = array(
                '#value' => $sharethis,
                '#weight' => variable_get('sharethis_sharethis_weight', 0),
              );
            }
          }
        }
      }
    break;
  }
}

/**
 * Implementation of hook_link().
 */
function sharethis_link($type, $node = NULL, $teaser = FALSE) {
  if ($type == 'node' && user_access('use share this')) {
    if (!$teaser || variable_get('sharethis_teaser', 1)) {
      if (variable_get('sharethis_sharethis_this_where', 'links') == 'links') {
        if (in_array($node->type, variable_get('sharethis_sharethis_this_node_types', array()), TRUE)) {
          // Make sure the ShareThis JavaScript is made available.
          sharethis_add_js();

          // Create the ShareThis element.
          $links['sharethis_link'] = array(
            'title' => t('ShareThis'),
            'href' => url('node/'. $node->nid, array('absolute' => TRUE)),
            'attributes' => array(
              'class' => 'sharethis-link', // This is the class that is processed.
              'title' => check_plain($node->title),
              'rel' => 'nofollow',
            ),
          );
          return $links;
        }
      }
    }
  }
}

/**
 * Implementation of hook_block().
 */
function sharethis_block($op = 'list', $delta = 0, $edit = array()) {
  switch ($op) {
    case 'list':
      $blocks['sharethis'] = array(
        'info' => t('ShareThis'),
        'cache' => BLOCK_NO_CACHE, // Don't cache it because it needs to add JavaScript.
      );
      return $blocks;
    break;
    case 'view':
      if ($delta == 'sharethis') {
        return array(
          'subject' => t('ShareThis'),
          'content' => theme('sharethis', drupal_get_title(), $_GET['q']),
        );
      }
    break;
  }
}

/**
 * Adds all required ShareThis JavaScript to the page.
 */
function sharethis_add_js() {
	// Be sure to add the ShareThis header code only once.
  static $sharethis_added = FALSE;
  if ($sharethis_added === FALSE) {
  	// Adds the ShareThis jQuery plugin as well as the related Drupal JavaScript behavior and CSS.
  	$path = drupal_get_path('module', 'sharethis');
    drupal_add_js($path . '/sharethis/jquery.sharethis.js');
    drupal_add_js($path . '/sharethis.js');

    // Add the ShareThis code if desired.
    $code = variable_get('sharethis_code', '');
    if (!empty($code)) {
      $code = str_replace('<script type="text/javascript" src="', '', $code);
      $code = str_replace('"></script>', '', $code);
      drupal_add_js(array('sharethisUrl' => $code), 'setting');
    }

    // Flag that the JavaScript has been registered.
    $sharethis_added = TRUE;
  }
}

/**
 * Implementation of hook_theme().
 */
function sharethis_theme() {
  return array(
    'sharethis' => array(
      'arguments' => array(
        'title' => NULL,
        'url' => NULL,
      ),
    ),
  );
}

/**
 * Themes the ShareThis options given.
 *
 * @param $title
 *   (optional) The name of the article you want to share. If not given, will
 *   use the title of the currently displayed page.
 * @param $url
 *   (optional) The URL of the article you want to share. If not given, will use
 *   the URL of the page you're currently on.
 * @return
 *   HTML for the ShareThis element.
 */
function theme_sharethis($title = NULL, $url = NULL) {
  // Add the JavaScript and render the HTML.
  sharethis_add_js();

  // Construct the ShareThis link using the title and the URL.
  $title = isset($title) ? $title : drupal_get_title();
  $url = isset($url) ? $url : $_GET['q'];
  return l(t('ShareThis'), $url, array(
    'absolute' => TRUE,
    'attributes' => array(
      'class' => 'sharethis-link',
      'title' => $title,
      'rel' => 'nofollow',
    ),
  ));
}

/**
 * Implementation of hook_views_api().
 */
function sharethis_views_api() {
  return array(
    'api' => 2,
  );
}