<?php
// $Id: print_mail.module,v 1.54 2010-07-27 16:42:57 jcnventura Exp $

/**
 * @file
 * Displays Printer-friendly versions of Drupal pages.
 *
 * @ingroup print
 */

define('PRINTMAIL_PATH', 'printmail');

define('PRINT_MAIL_FORMAT', 'mail');

define('PRINT_MAIL_LINK_POS_DEFAULT', 'link');
define('PRINT_MAIL_LINK_TEASER_DEFAULT', 0);
define('PRINT_MAIL_SHOW_LINK_DEFAULT', 1);
define('PRINT_MAIL_NODE_LINK_VISIBILITY_DEFAULT', 0);
define('PRINT_MAIL_NODE_LINK_PAGES_DEFAULT', '');
define('PRINT_MAIL_LINK_CLASS_DEFAULT', 'print-mail');
define('PRINT_MAIL_SYS_LINK_VISIBILITY_DEFAULT', 1);
define('PRINT_MAIL_SYS_LINK_PAGES_DEFAULT', '');
define('PRINT_MAIL_LINK_USE_ALIAS_DEFAULT', 0);
define('PRINT_MAIL_BOOK_LINK_DEFAULT', 1);
define('PRINT_MAIL_HOURLY_THRESHOLD', 3);
define('PRINT_MAIL_TEASER_DEFAULT_DEFAULT', 1);
define('PRINT_MAIL_TEASER_CHOICE_DEFAULT', 1);
define('PRINT_MAIL_SEND_OPTION_DEFAULT', 'sendpage');
define('PRINT_MAIL_JOB_QUEUE_DEFAULT', 0);

/**
 * Implements hook_permission().
 */
function print_mail_permission() {
  return array(
    'access send to friend' => array(
      'title' => t('Access the Send To Friend functionality'),
      'description' => t('Provides the ability to send pages to a friend and the links to them in the original pages.'),
    ),
  );
}

/**
 * Implements hook_theme().
 */
function print_mail_theme() {
  return array(
    'print_mail_format_link' => array(
      'variables' => array(),
    ),
    'print_mail_form' => array(
      'variables' => array('form' => NULL),
      'file' => 'print_mail.inc',
    ),
  );
}

/**
 * Implements hook_menu().
 */
function print_mail_menu() {
  $items = array();

  $items[PRINTMAIL_PATH] = array(
    'title' => 'Send page by e-mail',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('print_mail_form'),
    'access callback' => '_print_mail_access',
    'access arguments' => array('access send to friend'),
    'type' => MENU_CALLBACK,
    'file' => 'print_mail.inc',
  );
  $items[PRINTMAIL_PATH . '/' . PRINTMAIL_PATH] = array(
    'access callback' => FALSE,
  );
  $items['admin/config/print/email'] = array(
    'title' => 'e-mail',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('print_mail_settings'),
    'access arguments'  => array('administer print'),
    'weight' => 2,
    'type' => MENU_LOCAL_TASK,
    'file' => 'print_mail.admin.inc',
  );
  $items['admin/config/print/email/options'] = array(
    'title' => 'Options',
    'weight' => 1,
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['admin/config/print/email/strings'] = array(
    'title' => 'Text strings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('print_mail_strings_settings'),
    'access arguments'  => array('administer print'),
    'weight' => 2,
    'type' => MENU_LOCAL_TASK,
    'file' => 'print_mail.admin.inc',
  );

  return $items;
}

/**
 * Implements hook_block_info().
 */
function print_mail_block_info() {
      $block['print_mail-top']['info'] = t('Most emailed');
      $block['print_mail-top']['cache'] = DRUPAL_CACHE_GLOBAL;
      return $block;
}

/**
 * Implements hook_block_view().
 */
function print_mail_block_view($delta = 0) {
      switch ($delta) {
      case 'print_mail-top':
        $block['subject'] = t('Most emailed');
        $result = db_query_range("SELECT path FROM {print_mail_page_counter} ORDER BY sentcount DESC", 0, 3)
                    ->fetchAll();
        if (count($result)) {
          $block['content'] = '<div class="item-list"><ul>';
          foreach ($result as $obj) {
            $block['content'] .= '<li>' . l(_print_get_title($obj->path), $obj->path) . '</li>';
          }
          $block['content'] .= '</ul></div>';
        }
        break;
      }
      return $block;
}

/**
 * Implements hook_node_view().
 */
function print_mail_node_view($node, $build_mode) {
  $print_mail_link_pos = variable_get('print_mail_link_pos', array(PRINT_MAIL_LINK_POS_DEFAULT => PRINT_MAIL_LINK_POS_DEFAULT));
  $print_mail_link_use_alias = variable_get('print_mail_link_use_alias', PRINT_MAIL_LINK_USE_ALIAS_DEFAULT);
  $allowed_type = print_mail_link_allowed(array('type' => 'node', 'node' => $node, 'teaser' => ($build_mode == 'teaser')));
  if (($allowed_type) && !empty($print_mail_link_pos['link'])) {
    drupal_add_css(drupal_get_path('module', 'print') . '/css/printlinks.css');
    $links = array();
    $format = theme('print_mail_format_link');

    // Show book link
    if ($allowed_type === PRINT_ALLOW_BOOK_LINK) {
      $links['book_mail'] = array('href' => PRINTMAIL_PATH . '/book/export/html/' . $node->nid,
                                 'title' => $format['text'],
                                 'attributes' => $format['attributes'],
                                 'html' => $format['html'],
      );
    }
    elseif ($allowed_type === PRINT_ALLOW_NORMAL_LINK) {
      $query_arr = $_GET;
      if ('node' == 'comment') {
        $query_arr['comment'] = $node->cid;
      }
      $query = print_query_string_encode($query_arr, array('q'));
      if (empty($query)) $query = NULL;

      if ($print_mail_link_use_alias) {
        $path = drupal_get_path_alias('node/' . $node->nid);
      }
      else {
        $path = $node->nid;
      }

      $links['print_mail'] = array('href' => PRINTMAIL_PATH . '/' . $path,
                                  'title' => $format['text'],
                                  'attributes' => $format['attributes'],
                                  'html' => $format['html'],
                                  'query' => $query,
      );
    }

    $node->content['links']['print_mail'] = array(
      '#theme' => 'links',
      '#links' => $links,
      '#attributes' => array('class' => array('links', 'inline')),
    );
  }

  // Insert content corner links
  if (!empty($print_mail_link_pos['corner']) && ($build_mode == 'full')) {
    $node->content['print_links']['#markup'] .= print_mail_insert_link(NULL, $node);
  }
}

/**
 * Implements hook_help().
 */
function print_mail_help($path, $arg) {
  $print_mail_link_pos = variable_get('print_mail_link_pos', array(PRINT_MAIL_LINK_POS_DEFAULT => PRINT_MAIL_LINK_POS_DEFAULT));
  if (($path !== 'node/%') && !(empty($print_mail_link_pos['link']) && empty($print_mail_link_pos['corner']))) {
    static $output = FALSE;

    if ($output === FALSE) {
      $output = TRUE;

      $link = print_mail_insert_link();
      if ($link) {
        return "<span class='print-syslink'>$link</span>";
      }
    }
  }
}

/**
 * Implements hook_node_load().
 */
function print_mail_node_load($nodes, $types) {
  foreach ($nodes as $node) {
    _print_mail_set_node_fields($node);
  }
}

/**
 * Implements hook_node_insert().
 */
function print_mail_node_insert($node) {
  if (user_access('administer print') || user_access('node-specific print configuration')) {
    if ($node->print_mail_display === NULL) $node->print_mail_display = variable_get('print_mail_display_' . $node->type, PRINT_TYPE_SHOW_LINK_DEFAULT);
    if ($node->print_mail_display_comment === NULL) $node->print_mail_display_comment = variable_get('print_mail_display_comment_' . $node->type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
    if ($node->print_mail_display_urllist === NULL) $node->print_mail_display_urllist = variable_get('print_mail_display_urllist_' . $node->type, PRINT_TYPE_URLLIST_DEFAULT);

    _print_mail_node_conf_modify($node->nid, $node->print_mail_display, $node->print_mail_display_comment, $node->print_mail_display_urllist);
  }
}

/**
 * Implements hook_node_update().
 */
function print_mail_node_update($node) {
  if (user_access('administer print') || user_access('node-specific print configuration')) {
    if ($node->print_mail_display === NULL) $node->print_mail_display = variable_get('print_mail_display_' . $node->type, PRINT_TYPE_SHOW_LINK_DEFAULT);
    if ($node->print_mail_display_comment === NULL) $node->print_mail_display_comment = variable_get('print_mail_display_comment_' . $node->type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
    if ($node->print_mail_display_urllist === NULL) $node->print_mail_display_urllist = variable_get('print_mail_display_urllist_' . $node->type, PRINT_TYPE_URLLIST_DEFAULT);

    _print_mail_node_conf_modify($node->nid, $node->print_mail_display, $node->print_mail_display_comment, $node->print_mail_display_urllist);
  }
}

/**
 * Implements hook_node_delete().
 */
function print_mail_node_delete($node) {
  db_delete('print_mail_node_conf')
    ->condition('nid', $node->nid)
    ->execute();
  db_delete('print_mail_page_counter')
    ->condition('path', 'node/' . $node->nid)
    ->execute();
}

/**
 * Implements hook_form_alter().
 */
function print_mail_form_alter(&$form, &$form_state, $form_id) {
  // Add the node-type settings option to activate the mail version link
  if ((user_access('administer print') || user_access('node-specific print configuration')) &&
      (($form_id == 'node_type_form') || !empty($form['#node_edit_form']))) {
    $form['print']['mail_label'] = array(
      '#type' => 'markup',
      '#markup' => '<p><strong>' . t('Send by e-mail') . '</strong></p>',
    );

    $form['print']['print_mail_display'] = array(
      '#type' => 'checkbox',
      '#title' => t('Show link'),
    );
    $form['print']['print_mail_display_comment'] = array(
      '#type' => 'checkbox',
      '#title' => t('Show link in individual comments'),
    );
    $form['print']['print_mail_display_urllist'] = array(
      '#type' => 'checkbox',
      '#title' => t('Show Printer-friendly URLs list'),
    );

    if ($form_id == 'node_type_form') {
      $form['print']['print_mail_display']['#default_value'] = variable_get('print_mail_display_' . $form['#node_type']->type, PRINT_TYPE_SHOW_LINK_DEFAULT);
      $form['print']['print_mail_display_comment']['#default_value'] = variable_get('print_mail_display_comment_' . $form['#node_type']->type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
      $form['print']['print_mail_display_urllist']['#default_value'] = variable_get('print_mail_display_urllist_' . $form['#node_type']->type, PRINT_TYPE_URLLIST_DEFAULT);
    }
    else {
      $node = $form['#node'];
      $form['print']['print_mail_display']['#default_value'] = isset($node->print_mail_display) ? $node->print_mail_display : variable_get('print_mail_display_' . $node->type, PRINT_TYPE_SHOW_LINK_DEFAULT);
      $form['print']['print_mail_display_comment']['#default_value'] = isset($node->print_mail_display_comment) ? $node->print_mail_display_comment : variable_get('print_mail_display_comment_' . $node->type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
      $form['print']['print_mail_display_urllist']['#default_value'] = isset($node->print_mail_display_urllist) ? $node->print_mail_display_urllist : variable_get('print_mail_display_urllist_' . $node->type, PRINT_TYPE_URLLIST_DEFAULT);
    }
  }
}

/**
 * Implements hook_job_queue_functions().
 */
function print_mail_job_queue_functions() {
  $functions['print_mail'] = array(
   'title' => t('Send to friend'),
  );
  return $functions;
}

/**
 * Access callback to check a combination of user_acess() and page access
 *
 * @param $permission
 *   permission required to view the page
 * @return
 *   TRUE if the user has permission to view the page, FALSE otherwise
 */
function _print_mail_access($permission) {
  $page_access = TRUE;
  $parts = explode('/', $_GET['q']);
  if (count($parts) > 1) {
    unset($parts[0]);
    $path = implode('/', $parts);
    if (is_numeric($parts[1])) {
      $path = 'node/' . $path;
    }
    // If the destination page is not accessible, don't show the form
    if (!($router_item = menu_get_item($path)) || (!$router_item['access'])) {
      $page_access = FALSE;
    }
  }

  return (user_access($permission) && $page_access);
}

/**
 * Auxiliary function to assign the per-node settings to the node object fields
 *
 * @param $node
 *   node to be modified
 */
function _print_mail_set_node_fields(&$node) {
  if (isset($node->nid)) {
    $res = db_query("SELECT link, comments, url_list FROM {print_mail_node_conf} WHERE nid = :nid", array(':nid' => $node->nid))
              ->fetch();
  }
  else {
    $res = FALSE;
  }
  $node->print_mail_display = $res ? intval($res->link) : variable_get('print_mail_display_' . $node->type, PRINT_TYPE_SHOW_LINK_DEFAULT);
  $node->print_mail_display_comment = $res ? intval($res->comments) : variable_get('print_mail_display_comment_' . $node->type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
  $node->print_mail_display_urllist = $res ? intval($res->url_list) : variable_get('print_mail_display_urllist_' . $node->type, PRINT_TYPE_URLLIST_DEFAULT);
}

/**
 * Update the print_mail_node_conf table to reflect the given attributes
 * If updating to the default values, delete the record.
 *
 * @param $nid
 *   value of the nid field (primary key)
 * @param $link
 *   value of the link field (0 or 1)
 * @param $comments
 *   value of the comments field (0 or 1)
 * @param $url_list
 *   value of the url_list field (0 or 1)
 */
function _print_mail_node_conf_modify($nid, $link, $comments, $url_list) {
    db_merge('print_mail_node_conf')
      ->key(array('nid' => $nid))
      ->fields(array(
        'link' => $link,
        'comments' => $comments,
        'url_list' => $url_list,
      ))
      ->execute();
}

/**
 * Format the send by e-mail link
 *
 * @return
 *   array of formatted attributes
 * @ingroup themeable
 */
function theme_print_mail_format_link() {
  $print_mail_link_class  = variable_get('print_mail_link_class', PRINT_MAIL_LINK_CLASS_DEFAULT);
  $print_mail_show_link = variable_get('print_mail_show_link', PRINT_MAIL_SHOW_LINK_DEFAULT);
  $print_mail_link_text = filter_xss(variable_get('print_mail_link_text', t('Send to friend')));

  $img = drupal_get_path('module', 'print') . '/icons/mail_icon.gif';
  $title = t('Send this page by e-mail.');
  $class = strip_tags($print_mail_link_class);
  $new_window = FALSE;
  $format = _print_format_link_aux($print_mail_show_link, $print_mail_link_text, $img);

  return array('text' => $format['text'],
               'html' => $format['html'],
               'attributes' => print_fill_attributes($title, $class, $new_window),
              );
}

/**
 * Auxiliary function to display a formatted send by e-mail link
 *
 * Function made available so that developers may call this function from
 * their defined pages/blocks.
 *
 * @param $path
 *   path of the original page (optional). If not specified, the current URL
 *   is used
 * @param $node
 *   an optional node object, to be used in defining the path, if used, the
 *   path argument is irrelevant
 * @return
 *   string with the HTML link to the printer-friendly page
 */
function print_mail_insert_link($path = NULL, $node = NULL) {
  if ($node !== NULL) {
    $nid = $node->nid;
    $path = 'node/' . $nid;
    $allowed_type = print_mail_link_allowed(array('node' => $node));
  }
  else {
    if ($path === NULL) {
      $nid = preg_replace('!^node/!', '', $_GET['q']);
      $path = $_GET['q'];
    }
    else {
      $nid = NULL;
    }
    $allowed_type = print_mail_link_allowed(array('path' => $path));
  }

  if ($allowed_type) {
    if ($nid !== NULL) {
      if ($allowed_type === PRINT_ALLOW_BOOK_LINK) {
        $path = 'book/export/html/' . $nid;
      }
      else {
        if (variable_get('print_mail_link_use_alias', PRINT_MAIL_LINK_USE_ALIAS_DEFAULT)) {
          $path = drupal_get_path_alias($path);
        }
        else {
          $path = $nid;
        }
      }
      $path = PRINTMAIL_PATH . '/' . $path;
      $query = print_query_string_encode($_GET, array('q'));
      if (empty($query)) {
        $query = NULL;
      }
    }
    else {
      $query = NULL;
    }
    drupal_add_css(drupal_get_path('module', 'print') . '/css/printlinks.css');
    $format = theme('print_mail_format_link');
    return '<span class="print_mail">' . l($format['text'], $path, array('attributes' => $format['attributes'], 'query' => $query, 'absolute' => TRUE, 'html' => $format['html'])) . '</span>';
  }
  else {
    return FALSE;
  }
}

/**
 * Determine a the link to send by e-mail is allowed depending on all possible settings
 *
 * @param $args
 *   array containing the possible parameters:
 *    teaser, node, type, path
 * @return
 *   FALSE if not allowed
 *   PRINT_ALLOW_NORMAL_LINK if a normal link is allowed
 *   PRINT_ALLOW_BOOK_LINK if a link is allowed in a book node
 */
function print_mail_link_allowed($args) {
  if ((!empty($args['teaser']) && !variable_get('print_mail_link_teaser', PRINT_MAIL_LINK_TEASER_DEFAULT))
      || !user_access('access send to friend')) {
    // If the teaser link is disabled or the user is not allowed
    return FALSE;
  }
  if (!empty($args['path'])) {
    $nid = preg_replace('!^node/!', '', drupal_get_normal_path($args['path']));
    if (is_numeric($nid)) {
      $args['node'] = node_load($nid);
    }
  }
  if (!empty($args['node'])) {
    static $node_type = FALSE;

    $node = $args['node'];
    if (isset($node->type)) {
      $node_type = $node->type;
    }
    // Node
    $print_mail_node_link_visibility = variable_get('print_mail_node_link_visibility', PRINT_MAIL_NODE_LINK_VISIBILITY_DEFAULT);
    $print_mail_node_link_pages = variable_get('print_mail_node_link_pages', PRINT_MAIL_NODE_LINK_PAGES_DEFAULT);

    if (!_print_page_match($print_mail_node_link_visibility, "node/" . $node->nid, $print_mail_node_link_pages)) {
      // Page not in visibility list
      return FALSE;
    }
    elseif (isset($args['type']) && ($args['type'] == 'comment') && isset($node_type)) {
      // Link is for a comment, return the configured setting
      $res = db_query("SELECT comments FROM {print_mail_node_conf} WHERE nid = :nid", array(':nid' => $node->nid))
                ->fetch();
      $print_display_comment = $res ? intval($res->comments) : variable_get('print_mail_display_comment_' . $node_type, PRINT_TYPE_COMMENT_LINK_DEFAULT);
      if ($print_display_comment) {
        return PRINT_ALLOW_NORMAL_LINK;
      }
    }
    else {
      // Node link
      if (!$node->print_mail_display) {
        // Link for this node is disabled
        return FALSE;
      }
      elseif (isset($node->book)) {
        // Node is a book;
        $print_mail_book_link = variable_get('print_mail_book_link', PRINT_MAIL_BOOK_LINK_DEFAULT);
        switch ($print_mail_book_link) {
          case 1:
            if (user_access('access printer-friendly version')) {
              return PRINT_ALLOW_BOOK_LINK;
            }
            break;
          case 2:
            return PRINT_ALLOW_NORMAL_LINK;
        }
      }
      else {
        return PRINT_ALLOW_NORMAL_LINK;
      }
    }
  }
  else {
    // 'System' page
    $print_mail_sys_link_visibility = variable_get('print_mail_sys_link_visibility', PRINT_MAIL_SYS_LINK_VISIBILITY_DEFAULT);
    $print_mail_sys_link_pages = variable_get('print_mail_sys_link_pages', PRINT_MAIL_SYS_LINK_PAGES_DEFAULT);

    return _print_page_match($print_mail_sys_link_visibility, $_GET['q'], $print_mail_sys_link_pages);
  }
  return FALSE;
}