<?php
// $Id: custom_breadcrumbs.module,v 1.5.2.13 2009-09-19 06:53:18 mgn Exp $

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

  if ($may_cache) {
    $access = user_access('administer custom breadcrumbs');
    $items[] = array(
      'path' => 'admin/build/custom_breadcrumbs',
      'title' => t('Custom breadcrumbs'),
      'description' => t('Add custom breadcrumb trails for content types.'),
      'callback' => 'custom_breadcrumbs_page',
      'access' => $access
    );

    $items[] = array(
      'path' => 'admin/build/custom_breadcrumbs/add',
      'title' => t('Add custom breadcrumb'),
      'type' => MENU_CALLBACK,
      'callback' => 'drupal_get_form',
      'callback arguments' => array('custom_breadcrumbs_form'),
      'access' => $access
    );

    $items[] = array(
      'path' => 'admin/build/custom_breadcrumbs/edit',
      'title' => t('Edit custom breadcrumb'),
      'type' => MENU_CALLBACK,
      'callback' => 'drupal_get_form',
      'callback arguments' => array('custom_breadcrumbs_form'),
      'access' => $access
    );
  }

  return $items;
}

function custom_breadcrumbs_perm() {
  return array('administer custom breadcrumbs', 'use php in custom breadcrumbs');
}

function custom_breadcrumbs_nodeapi($node, $op, $teaser, $page) {
  if ($op == 'view' && !$teaser && $page) {
    if ($breadcrumb = _custom_breadcrumbs_load_for_type($node)) {
      $titles = preg_split("/[\n]+/", $breadcrumb->titles);
      $paths = preg_split("/[\n]+/", $breadcrumb->paths);
      $titles = module_exists('token') ? token_replace($titles, 'node', $node) : $titles;
      $paths = module_exists('token') ? token_replace($paths, 'node', $node) : $paths;

      $trail = array(l(t('Home'), ''));
      $location = array();
      for ($i = 0; $i < count($titles); $i++) {
        // Skip empty titles
        if ($title = trim($titles[$i])) {
          $title = ($title == '<none>') ? ' ' : decode_entities($title);
          // Output plaintext instead of a link if there is a title without a path.
          $path = trim($paths[$i]);
          if (strlen($path) > 0 && $path != '<none>') {
            $parsed = parse_url($path);
            $trail[] = l($title, $parsed['path'], array(), $parsed['query']);
          }
          else {
            $trail[] = check_plain($title);
          }
          $location[] = array ('title' => $title, 'path' => drupal_get_normal_path($path));
        }
      }
      drupal_set_breadcrumb($trail);
      menu_set_location($location);
    }
  }
}

// Lists all current custom breadcrumbs, and provides a link to the edit page.
function custom_breadcrumbs_page() {
  $breadcrumbs = _custom_breadcrumbs_load_all_breadcrumbs(TRUE);

  $header = array(t('node type'), '');

  $rows = array();
  foreach ($breadcrumbs as $breadcrumb) {
    $row = array();
    $row[] = $breadcrumb->node_type . (!empty($breadcrumb->visibility_php) ? t(' with PHP snippet') : '');
    $row[] =  l(t('edit'), 'admin/build/custom_breadcrumbs/edit/' . $breadcrumb->bid);
    $rows[] = $row;
  }
  if (count($rows) == 0) {
    $rows[] = array(array('data' => t('No custom breadcrumbs have been defined.'), 'colspan' => 2));
  }

  $rows[] = array(array('data' => l(t('Add a new custom breadcrumb'), 'admin/build/custom_breadcrumbs/add'), 'colspan' => 2));

  return theme('table', $header, $rows);
}

// Displays an edit form for a custom breadcrumb record.
function custom_breadcrumbs_form() {
  $bid = arg(4);
  if (isset($bid)) {
    $breadcrumb = _custom_breadcrumbs_load_breadcrumb($bid);
    $form['bid'] = array(
      '#type' => 'hidden',
      '#value' => $bid,
    );
  }

  $options = array();
  foreach (node_get_types('names') as $type => $name) {
    $options[$type] = $name;
  }

  $form['node_type'] = array(
    '#type' => 'select',
    '#title' => t('Node type'),
    '#required' => TRUE,
    '#options' => $options,
    '#description' => t('The node type this custom breadcrumb trail will apply to.'),
    '#default_value' => $bid ? $breadcrumb->node_type : NULL,
  );

  $form['visibility_php'] = array(
    '#type' => 'textarea',
    '#title' => t('Breadcrumb visibility'),
    '#access' => user_access('use php in custom breadcrumbs'),
    '#description' => t('Determine whether this breadcrumb should be displayed by using a snippet of PHP to return TRUE or FALSE. Note that this code has access to the $node variable, and can check its type or any other property.'),
    '#default_value' => $bid ? $breadcrumb->visibility_php : '',
  );

  $form['titles'] = array(
    '#type' => 'textarea',
    '#title' => t('Titles'),
    '#required' => TRUE,
    '#description' => t('A list of titles for the breadcrumb links, one on each line.'),
    '#default_value' => $bid ? $breadcrumb->titles : NULL
  );

  $form['paths'] = array(
    '#type' => 'textarea',
    '#title' => t('Paths'),
    '#required' => TRUE,
    '#description' => t('A list of Drupal paths for the breadcrumb links, one on each line.'),
    '#default_value' => $bid ? $breadcrumb->paths : NULL
  );

  $form['help'] = array(
    '#type' => 'fieldset',
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#title' => t('Placeholder tokens'),
    '#description' => t("The following placeholder tokens can be used in both paths and titles. When used in a path or title, they will be replaced with the appropriate values."),
  );

  if (module_exists('token')) {
    $form['help']['tokens'] = array(
      '#value' => theme('token_help', 'node'),
    );
  }
  else {
    $form['help']['#description'] = t("To use dynamic placeholder tokens in your breadcrumb trails (the ID or title of the current node, for example), download and install the <a href='@token'>Token module</a> from Drupal.org.", array('@token' => 'http://www.drupal.org/project/token'));
    $form['help']['#collapsible'] = FALSE;
    $form['help']['#collapsed'] = FALSE;
  }

  $form['buttons']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  if ($bid) {
    $form['buttons']['delete'] = array(
      '#type' => 'submit',
      '#value' => t('Delete'),
    );
  }

  return $form;
}

function custom_breadcrumbs_form_validate($form_id, $form_values) {
  $path_count = count(explode("\n", $form_values['paths']));
  $title_count = count(explode("\n", $form_values['titles']));
  if ($title_count != $path_count) {
    $error_field = ($title_count > $path_count) ? 'paths' : 'titles';
    form_set_error($error_field, t('Every link path must have a matching title. There are !paths paths, and !titles titles.', array('!paths' => $path_count, '!titles' => $title_count)));
  }
}

function custom_breadcrumbs_form_submit($form_id, $form_values) {
  if ($form_values['op'] == t('Delete')) {
    _custom_breadcrumbs_delete_breadcrumb($form_values['bid']);
  }
  else {
    $breadcrumb = (object)$form_values;
    custom_breadcrumbs_save_breadcrumb($breadcrumb);
  }
  return 'admin/build/custom_breadcrumbs';
}

function _custom_breadcrumbs_load_breadcrumb($bid) {
  $sql = 'SELECT * FROM {custom_breadcrumb} WHERE bid = %d';
  $result = db_query($sql, $bid);
  $breadcrumb = db_fetch_object($result);
  return $breadcrumb;
}

function _custom_breadcrumbs_load_for_type($node) {
  $sql = "SELECT * FROM {custom_breadcrumb} WHERE node_type = '%s'";
  $result = db_query($sql, $node->type);
  while ($breadcrumb = db_fetch_object($result)) {
    if (!empty($breadcrumb->visibility_php)) {
      // Use PHP code to check the visibility.
      ob_start();
      $visibility = eval(trim($breadcrumb->visibility_php));
      ob_end_clean();
      if ($visibility == TRUE) {
        return $breadcrumb;
      }
    }
    else {
      return $breadcrumb;
    }
  }
}

function _custom_breadcrumbs_load_all_breadcrumbs($refresh = FALSE) {
  static $breadcrumbs;
  if ($refresh || !isset($breadcrumbs)) {
    $sql = 'SELECT * FROM {custom_breadcrumb} ORDER BY node_type';
    $result = db_query($sql);

    $breadcrumbs = array();
    while($breadcrumb = db_fetch_object($result)) {
      $breadcrumbs[] = $breadcrumb;
    }
  }
  return $breadcrumbs;
}

function custom_breadcrumbs_save_breadcrumb($breadcrumb = NULL) {
  if (is_array($breadcrumb->paths)) {
    $breadcrumb->paths = implode("\n", $breadcrumb->paths);
  }
  if (is_array($breadcrumb->titles)) {
    $breadcrumb->titles = implode("\n", $breadcrumb->titles);
  }

  if (isset($breadcrumb->bid)) {
    $sql  = "UPDATE {custom_breadcrumb} SET";
    $sql .= " titles = '%s', paths = '%s', visibility_php = '%s', node_type = '%s'";
    $sql .= " WHERE bid = %d";
    db_query($sql, $breadcrumb->titles, $breadcrumb->paths, $breadcrumb->visibility_php, $breadcrumb->node_type, $breadcrumb->bid);
  }
  else {
    $sql  = "INSERT INTO {custom_breadcrumb}";
    $sql .= " (titles, paths, visibility_php, node_type)";
    $sql .= " VALUES ('%s',  '%s',  '%s', '%s')";
    db_query($sql, $breadcrumb->titles, $breadcrumb->paths, $breadcrumb->visibility_php, $breadcrumb->node_type);
  }
}

function _custom_breadcrumbs_delete_breadcrumb($bid) {
  $sql = 'DELETE FROM {custom_breadcrumb} WHERE bid = %d';
  db_query($sql, $bid);
}