<?php
/* $Id$ */

/**
 * @file
 * Display printer friendly versions of nodes (except books)
 */

/********************************************************************
 * Drupal Hooks :: Overview
 ********************************************************************/

/**
 * Implementation of hook_menu().
 */
function print_menu($may_cache) {
  $items = array();

  if ($may_cache) {
    $items[] = array(
      'path' => 'print',
      'title' => t('Printer friendly'),
      'callback' => 'print_controller',
      'access' => user_access('access content'),
      'type' => MENU_CALLBACK
    );
    $items[] = array(
      'path' => 'admin/settings/print',
      'title' => t('Printer friendly'),
      'description' => t('Adds a printer-friendly version link to node pages.'),
      'callback' => 'drupal_get_form',
      'callback arguments' => array('print_main_settings')
    );
  }
  else {
    $nid = arg(1);
    if (is_numeric($nid)) {
      $items[] = array(
        'path' => 'print/'. $nid,
        'title' => t('Printer friendly'),
        'callback' => 'print_node_controller',
        'callback arguments' => array($nid),
        'type' => MENU_CALLBACK
      );
    }
  }

  return $items;
}

/********************************************************************
 * Drupal Hooks :: Core
 ********************************************************************/

/**
 * Implementation of hook_link().
 */
function print_link($type, $node = 0, $main) {
  $links = array();

  if ($node->type == 'book' && function_exists('book_link'))  {
    return;
  }

  if ($type == 'node' && variable_get('print_show_link', 1) && $main == 0) {
    $links['print'] = theme('print_link', $node);
  }

  return $links;
}

function print_main_settings() {
  $form['print_show_link'] = array(
    '#type' => 'radios',
    '#title' => t('Printer friendly page link'),
    '#default_value' => variable_get('print_show_link', 1),
    '#options' => array(t("Disabled"), t("Enabled")),
    '#description' => t("Enable or disable the printer friendly page link for each node. Even if the link is disabled, you can still view the print version of a node by going to print/nid where nid is the numeric id of the node."),
  );

  $print_settings = variable_get('print_settings', NULL);

  $form['print_settings'] = array(
      '#type' => 'fieldset',
      '#title' => t('Print settings'),
      '#tree' => TRUE,
    );

  $form['print_settings']['logo_url'] = array(
    '#type' => 'textfield',
    '#title' => t('Logo URL'),
    '#default_value' => !isset($print_settings['logo_url']) ? '' : $print_settings['logo_url'],
    '#size' => 60,
    '#maxlength' => 250,
    '#description' => t('An alternative logo to display on the printer friendly version'),
  );

  $form['print_settings']['css'] = array(
    '#type' => 'textfield',
    '#title' => t('Stylesheet URL'),
    '#default_value' => !isset($print_settings['css']) ? 'misc/print.css' : $print_settings['css'],
    '#size' => 60,
    '#maxlength' => 64,
    '#description' => t('The URL to your print cascading stylesheet.'),
  );

  $form['print_settings']['urls'] = array(
    '#type' => 'checkbox',
    '#title' => t('Printer friendly URLs'),
    '#return_value' => 1,
    '#default_value' => !isset($print_settings['urls']) ? 1 : $print_settings['urls'],
  );

  $print_robot_settings = variable_get('print_robot_settings', NULL);

  $form['print_robot_settings'] = array(
      '#type' => 'fieldset',
      '#title' => t('Robots META tags'),
      '#tree' => TRUE,
  );

  $form['print_robot_settings']['noindex'] = array(
    '#type' => 'checkbox',
    '#title' => t('Add noindex'),
    '#return_value' => 1,
    '#default_value' => empty($print_robot_settings['noindex']) ? 0 : 1,
    '#description' => t('Instruct robots to not index printer friendly pages')
  );

  $form['print_robot_settings']['nofollow'] = array(
    '#type' => 'checkbox',
    '#title' => t('Add nofollow'),
    '#return_value' => 1,
    '#default_value' => empty($print_robot_settings['nofollow']) ? 0 : 1,
    '#description' => t('Instruct robots to not follow outgoing links on printer friendly pages')
  );

  $form['print_robot_settings']['noarchive'] = array(
    '#type' => 'checkbox',
    '#title' => t('Add noarchive'),
    '#return_value' => 1,
    '#default_value' => empty($print_robot_settings['noarchive']) ? 0 : 1,
    '#description' => t('Non-standard tag to instruct search engines to not show a "Cached" link for your printer friendly pages. Recognized by Googlebot.')
  );

  $form['print_robot_settings']['nocache'] = array(
    '#type' => 'checkbox',
    '#title' => t('Add nocache'),
    '#return_value' => 1,
    '#default_value' => empty($print_robot_settings['nocache']) ? 0 : 1,
    '#description' => t('Non-standard tag to instruct search engines to not show a "Cached" link for your printer friendly pages')
  );

  return system_settings_form($form);
}

/********************************************************************
 * Module Functions :: Controllers
 ********************************************************************/

function print_node_controller($nid) {
  print_generate_node($nid);
}

function print_controller($module) {
  $f = 'print_generate_'. $module;

  if (function_exists($f)) {
    $f();
  }
}

/********************************************************************
 * Module Functions
 ********************************************************************/

/**
 * Generates a meta tag to tell robots what they may index based on module settings
 *
 * @return string
 */
function _print_robots_meta_generator() {
  $robots_settings = variable_get('print_robot_settings', NULL);
  $robots_meta = array();

  if(!empty($robots_settings['noindex'])) {
    $robots_meta[] = 'noindex';
  }
  if(!empty($robots_settings['nofollow'])) {
    $robots_meta[] = 'nofollow';
  }
  if(!empty($robots_settings['noarchive'])) {
    $robots_meta[] = 'noarchive';
  }
  if(!empty($robots_settings['nocache'])) {
    $robots_meta[] = 'nocache';
  }

  if(sizeof($robots_meta) > 0) {
    $robots_meta = isset($robots_meta[1]) ? implode(', ', $robots_meta) : $robots_meta[0];
    $robots_meta = '<meta name="robots" content="'. $robots_meta ."\" />\n";
  } else {
    $robots_meta = '';
  }

  return $robots_meta;
}

function print_convert_abspath($matches) {
  $path = $matches[2];
  if (strpos($path, '://') || preg_match("/^mailto:.*?@.*?\..*?$/iu", $path) || ((substr($path, 0, 1) == "#")) ) {
    // URL is OK, do not touch
  } else {
    $path = url(trim($path, "/"), NULL, NULL, TRUE);
  }
  
  return $matches[1].$path.$matches[3];
}

/**
 * Outputs a printer friendly page.
 */
function print_generate_node($title) {
  global $base_url;

  /* We can take a node id or a node title */
  $node = (is_numeric($title)) ? node_load(array('nid' => $title)) : node_load(array('title' => $title));
  if (!$node->title) return false;

  $teaser = false;
  $page = true;

  // To work with other node types, use drupal's render engine instead of the old node_view method
  $node->body = drupal_render(node_build_content($node)->content);

  // Relative links need to be changed to absolute paths since we the printer friendly page is not in the original URL
  // First the href links
  $pattern ="@(<a[^>]*?href=[\']?[\"]?)([^\"|^\'|^|^>]*)(.+?</a>)@is";
  $node->body = preg_replace_callback($pattern, "print_convert_abspath", $node->body);
  // Now the src links
  $pattern ="@(<[^>]*?src=[\']?[\"]?)([^\"|^\'|^|^>]*)(.+?>)@is";
  $node->body = preg_replace_callback($pattern, "print_convert_abspath", $node->body);

  // associative array settings
  $print_settings = variable_get('print_settings', NULL);

  if (!isset($print_settings['urls']) || !empty($print_settings['urls'])) {
    /* Collect links and display them at the bottom of the page. Code once taken from Kjartan Mannes' project.module  */
    $pattern = "@<a[^>]*?href=([\']?[\"]?)([^\"|^\'|^|^>]*)([^>]*)>(.+?)</a>@ise";
    $node->body = preg_replace($pattern, "'<span style=\'text-decoration:underline\'>'.stripslashes('\\4').'</span> ['. print_friendly_urls(trim(stripslashes('\\2')), $node->nid) .']'", $node->body);
    $urls = print_friendly_urls();
    if (count($urls)) {
      $node->pfp_links = '';
      $max = count($urls);
      for ($i = 0; $i < $max; $i++) {
        $node->pfp_links .= '['. ($i + 1) .'] '. $urls[$i] ."<br />\n";
      }
    }
  }

  init_theme();
  $node->logo = !empty($print_settings['logo_url']) ? $print_settings['logo_url'] : theme_get_setting('logo');

  /* Grab and format the src URL */
  $node->source_url = url("node/$node->nid", NULL, NULL, TRUE);
  $node->language = $GLOBALS['locale'];
  $node->printcss = empty($print_settings['css']) ? 'misc/print.css' : $print_settings['css'];

  $robots_meta = _print_robots_meta_generator();

  include_once('print.node.tpl.php');
}


function print_friendly_urls($url = 0, $nid) {
  static $urls = array();
  if ($url) {
    if(strpos($url, '://') || preg_match("/^mailto:.*?@.*?\..*?$/iu", $url)) {
      $urls[] = $url;
    } else {
      // Convert into absolute URL, removing extra beginning and end '/'
      if (substr($url, 0, 1) == "#") {
        // Handle <a name> tags
        $urls[] = url("node/" . $nid, NULL, substr($url,1), TRUE);
      } else {
        $urls[] = url(trim($url,"/"), NULL, NULL, TRUE);
      }
    }
    return count($urls);
  }
  return $urls;
}

/********************************************************************
 * Module Functions :: Themeable Functions
 ********************************************************************/

function theme_print_link($node) {
  return array('title' => t('Printer friendly version'),
           'href' => "print/$node->nid",
           'attributes' => array('title' => t('Display a printer friendly version of this page.')),
         );
}