<?php
// $Id: xmlsitemap_taxonomy.module,v 1.9 2010/01/20 03:34:29 davereid Exp $

/**
 * Implements hook_cron().
 *
 * Process old taxonomy terms not found in the {xmlsitemap} table.
 */
function xmlsitemap_taxonomy_cron() {
  xmlsitemap_taxonomy_xmlsitemap_index_links(xmlsitemap_var('batch_limit'));
}

/**
 * Implements hook_xmlsitemap_index_links().
 */
function xmlsitemap_taxonomy_xmlsitemap_index_links($limit) {
  if ($vids = xmlsitemap_taxonomy_get_vids()) {
    $tids = db_query_range("SELECT t.tid FROM {term_data} t LEFT JOIN {xmlsitemap} x ON x.type = 'taxonomy_term' AND t.tid = x.id WHERE x.id IS NULL AND t.vid IN (:vids) ORDER BY t.tid DESC", 0, $limit, array(':vids' => $vids));
    foreach ($tids as $tid) {
      $term = xmlsitemap_taxonomy_taxonomy_term_load($tid);
      $link = xmlsitemap_taxonomy_create_link($term);
      xmlsitemap_save_link($link);
    }
  }
}

/**
 * Implements hook_xmlsitemap_links().
 */
function xmlsitemap_taxonomy_xmlsitemap_links($offset = 0, $limit = 0) {
  $links = array();

  if ($vids = xmlsitemap_taxonomy_get_vids()) {
    $sql = "SELECT t.tid FROM {term_data} t WHERE t.tid > :tid AND t.vid IN (:vids) ORDER BY t.tid";
    $args = array(':tid' => $offset, ':vids' => $vids);
    $tids = ($limit ? db_query_range($sql, 0, $limit, $args) : db_query($sql, $args));

    foreach ($tids as $tid) {
      $term = xmlsitemap_taxonomy_taxonomy_term_load($tid);
      $links[] = xmlsitemap_taxonomy_create_link($term);
    }
  }

  return $links;
}

/**
 * Implements hook_xmlsitemap_links_batch_info().
 */
function xmlsitemap_taxonomy_xmlsitemap_links_batch_info() {
  $vids = xmlsitemap_taxonomy_get_vids();
  return array(
    'max' => $vids ? db_query("SELECT COUNT(t.tid) FROM {term_data} t WHERE t.vid IN (:vids)", array(':vids' => $vids))->fetchField() : 0,
  );
}

/**
 * Implements hook_xmlsitemap_link_info().
 */
function xmlsitemap_taxonomy_xmlsitemap_link_info() {
  return array(
    'taxononomy' => array(
      'purge' => TRUE,
      'table' => 'term_data',
      'id' => 'tid',
      'subtype' => 'vid',
      'subtypes' => xmlsitemap_taxonomy_get_vids(),
    ),
  );
}

/**
 * Load a taxonomy term and its associated sitemap link data.
 *
 * Use this instead of taxonomy_get_term().
 *
 * @todo Convert this to hook_taxonomy_term_load() in Drupal 7.
 */
function xmlsitemap_taxonomy_taxonomy_term_load($tid) {
  $term = taxonomy_get_term($tid);
  if ($data = xmlsitemap_load_link(array('type' => 'taxonomy_term', 'id' => $tid))) {
    $term->xmlsitemap = $data;
  }
  return $term;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Show a summary of vocabularies on the XML sitemap settings page.
 */
function xmlsitemap_taxonomy_form_xmlsitemap_settings_form_alter(&$form, $form_state) {
  $type = array(
    'type' => 'taxonomy_term',
    'title' => t('Taxonomy'),
    'item_title' => t('Vocabulary'),
    'access' => user_access('administer taxonomy'),
  );

  $vocabularies = taxonomy_get_vocabularies();
  foreach ($vocabularies as $vid => $vocabulary) {
    $vocabularies[$vid] = array(
      'name' => $vocabulary->name,
      'link' => 'admin/content/taxonomy/edit/vocabulary/' . $vid,
      'status' => xmlsitemap_taxonomy_var('status_' . $vid),
      'priority' => xmlsitemap_taxonomy_var('priority_' . $vid),
    );
  }

  xmlsitemap_add_form_type_summary($form, $type, $vocabularies);
  $form['taxonomy_term']['#weight'] = 40;
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * @see taxonomy_form_vocabulary()
 * @see xmlsitemap_add_form_type_options()
 */
function xmlsitemap_taxonomy_form_taxonomy_form_vocabulary_alter(&$form, $form_state) {
  $vid = isset($form['vid']['#value']) ? $form['vid']['#value'] : 0;

  module_load_include('inc', 'xmlsitemap', 'xmlsitemap.admin');
  $options = array(
    'status' => variable_get('xmlsitemap_taxonomy_status_' . $vid, 0),
    'priority' => variable_get('xmlsitemap_taxonomy_priority_' . $vid, 0.5),
  );
  xmlsitemap_add_form_type_options($form, 'taxonomy', $options);

  // @todo Enable these features:
  //$form['xmlsitemap']['xmlsitemap_taxonomy_calculate_priority'] = array(
  //  '#type' => 'checkbox',
  //  '#title' => t('Calculate priority based on term depth and weight.'),
  //  '#default_value' => xmlsitemap_taxonomy_var('calculate_priority_' . $vid),
  //);
  //$form['xmlsitemap']['xmlsitemap_taxonomy_include_empty_terms'] = array(
  //  '#type' => 'checkbox',
  //  '#title' => t('Include terms that do not have any associated content.'),
  //  '#default_value' => xmlsitemap_taxonomy_var('include_empty_terms_' . $vid),
  //);

  // The submit and delete buttons need to be weighted down.
  $form['submit'] += array('#weight' => 50);
  if (isset($form['delete'])) {
    $form['delete'] += array('#weight' => 51);
  }

  $form['#submit'][] = 'xmlsitemap_taxonomy_taxonomy_form_vocabulary_submit';
}

/**
 * Form submit handler; update settings when a taxonomy vocabulary is saved.
 */
function xmlsitemap_taxonomy_taxonomy_form_vocabulary_submit($form, $form_state) {
  $vid = $form_state['values']['vid'];
  $new_status = $form_state['values']['xmlsitemap_taxonomy_status'];
  $new_priority = $form_state['values']['xmlsitemap_taxonomy_priority'];

  if ($new_status != variable_get('xmlsitemap_taxonomy_status_' . $vid, 0)) {
    xmlsitemap_update_links(array('status' => $new_status), array('type' => 'taxonomy_term', 'subtype' => $vid, 'status_override' => 0));
  }
  if ($new_priority != variable_get('xmlsitemap_taxonomy_priority_' . $vid, 0.5)) {
    xmlsitemap_update_links(array('priority' => $new_priority), array('type' => 'taxonomy_term', 'subtype' => $vid, 'priority_override' => 0));
  }

  variable_set('xmlsitemap_taxonomy_status_' . $vid, $new_status);
  variable_set('xmlsitemap_taxonomy_priority_' . $vid, $new_priority);
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function xmlsitemap_taxonomy_form_taxonomy_form_term_alter(&$form, $form_state) {
  // Because the same form is used for deletion in confirm_form, we must check
  // if the normal editing form elements are present. Hopefully this is fixed
  // in Drupal 7.
  if (isset($form['identification'])) {
    if ($form['#term']['tid']) {
      $term = xmlsitemap_taxonomy_taxonomy_term_load($form['#term']['tid']);
    }
    else {
      $term = (object) $form['#term'];
    }
    $term->vid = $form['vid']['#value'];
    $link = xmlsitemap_taxonomy_create_link($term);

    // Add the link options.
    module_load_include('inc', 'xmlsitemap', 'xmlsitemap.admin');
    xmlsitemap_add_form_link_options($form, $link);

    $form['xmlsitemap']['#access'] |= user_access('administer taxonomy');
    if (user_access('administer taxonomy')) {
      $form['xmlsitemap']['#description'] = t('The default priority for this vocabulary can be changed <a href="@link-type">here</a>.', array('@link-type' => url('admin/content/taxonomy/edit/vocabulary/' . $term->vid, array('query' => drupal_get_destination()))));
    }

    // The submit and delete buttons need to be weighted down.
    $form['submit'] += array('#weight' => 50);
    if (isset($form['delete'])) {
      $form['delete'] += array('#weight' => 51);
    }
  }
}

/**
 * Implements hook_taxonomy().
 */
function xmlsitemap_taxonomy_taxonomy($op, $type, $array = NULL) {
  if ($type == 'vocabulary') {
    $vid = $array['vid'];
    // Insert and update actions handled by xmlsitemap_taxonomy_taxonomy_form_vocabulary_submit().
    if ($op == 'delete') {
      xmlsitemap_delete_link(array('type' => 'taxonomy_term', 'subtype' => $vid));
      variable_del('xmlsitemap_taxonomy_status_' . $vid);
      variable_del('xmlsitemap_taxonomy_priority_' . $vid);
    }
  }
  if ($type == 'term') {
    $tid = $array['tid'];
    if ($op == 'insert' || $op == 'update') {
      $link = xmlsitemap_taxonomy_create_link((object) $array);
      xmlsitemap_save_link($link);
    }
    elseif ($op == 'delete') {
      xmlsitemap_delete_link(array('type' => 'taxonomy_term', 'id' => $tid));
    }
  }
}

/**
 * Create a sitemap link from a taxonomy term.
 *
 * @param $term
 *   A taxonomy term object.
 * @return
 *   An array representing a sitemap link.
 */
function xmlsitemap_taxonomy_create_link(stdClass $term) {
  if (!isset($term->xmlsitemap)) {
    $term->xmlsitemap = array();
  }

  $term->xmlsitemap += array(
    'id' => $term->tid,
    'type' => 'taxonomy_term',
    'subtype' => $term->vid,
    'loc' => taxonomy_term_path($term),
    'status' => variable_get('xmlsitemap_taxonomy_status_' . $term->vid, 0),
    'status_default' => variable_get('xmlsitemap_taxonomy_status_' . $term->vid, 0),
    'status_override' => 0,
    'priority' => variable_get('xmlsitemap_taxonomy_priority_' . $term->vid, 0.5),
    'priority_default' => variable_get('xmlsitemap_taxonomy_priority_' . $term->vid, 0.5),
    'priority_override' => 0,
  );

  // The following values must always be checked because they are volatile.
  // @todo How can/should we check taxonomy term access?
  $term->xmlsitemap['access'] = 1;
  $term->xmlsitemap['language'] = isset($term->language) ? $term->language : LANGUAGE_NONE;

  return $term->xmlsitemap;
}

/**
 * Calculate the priority of a taxonomy term based on depth and weight.
 */
function xmlsitemap_taxonomy_calculate_term_priority($term) {
  // Calculate priority.
  // Min weight = -128
  // Max weight = 127
  // Max depth = ?
  return NULL;
}

/**
 * Find the tree depth of a taxonomy term.
 *
 * @param $tid
 *   A term ID.
 * @return
 *   The tree depth of the term.
 */
function xmlsitemap_taxonomy_get_term_depth($tid) {
  static $depths = array();

  if (!isset($depths[$tid])) {
    if ($parent = db_query("SELECT parent FROM {term_hierarchy} WHERE tid = %d", $tid)->fetchField()) {
      // If the term has a parent, the term's depth is the parent's depth + 1.
      if (!isset($depths[$parent])) {
        $depths[$parent] = xmlsitemap_taxonomy_get_term_depth($parent);
      }
      $depths[$tid] = $depths[$parent] + 1;
    }
    else {
      // Term has no parents, so depth is 0.
      $depths[$tid] = 0;
    }
  }

  return $depths[$tid];
}

function xmlsitemap_taxonomy_get_node_count($term) {
  // @todo Use db_rewrite_sql() w/ switch user.
  return db_query_range("SELECT COUNT(tn.nid) FROM {term_node} tn LEFT JOIN {node n} USING (nid) WHERE tn.tid = :tid AND n.status = 1", 0, 1, array(':tid' => $term->tid))->fetchField();
}

/**
 * Fetch an array of vocabulary IDs to be included in the sitemap.
 */
function xmlsitemap_taxonomy_get_vids() {
  $vids = array_keys(taxonomy_get_vocabularies());
  foreach ($vids as $index => $vid) {
    if (!variable_get('xmlsitemap_taxonomy_status_' . $vid, 0)) {
      unset($vids[$index]);
    }
  }
  return $vids;
}

/**
 * Internal default variables for template_var().
 */
function xmlsitemap_taxonomy_variables() {
  $defaults = array(
    // Removed variables set to NULL.
    'xmlsitemap_taxonomy_include_empty_terms' => NULL,
    'xmlsitemap_taxonomy_calculate_priority' => NULL,
  );
  $vids = array_keys(taxonomy_get_vocabularies());
  foreach ($vids as $vid) {
    $defaults['xmlsitemap_taxonomy_status_' . $vid] = 0;
    $defaults['xmlsitemap_taxonomy_priority_' . $vid] = '0.5';
    $defaults['xmlsitemap_taxonomy_calculate_priority_' . $vid] = FALSE;
    $defaults['xmlsitemap_taxonomy_include_empty_terms_' . $vid] = FALSE;
    //$defaults += _xmlsitemap_taxonomy_variables_vid($vid);
  }
  return $defaults;
}

//function _xmlsitemap_taxonomy_variables_vid($vid) {
//  $defaults = array();
//  $defaults['xmlsitemap_taxonomy_status_' . $vid] = 0;
//  $defaults['xmlsitemap_taxonomy_priority_' . $vid] = 0.5;
//  $defaults['xmlsitemap_taxonomy_calculate_priority_' . $vid] = FALSE;
//  $defaults['xmlsitemap_taxonomy_include_empty_terms_' . $vid] = TRUE;
//  return $defaults;
//}

/**
 * Internal implementation of variable_get().
 */
function xmlsitemap_taxonomy_var($name, $default = NULL) {
  static $defaults = NULL;
  if (!isset($defaults)) {
    $defaults = xmlsitemap_taxonomy_variables();
  }

  $name = 'xmlsitemap_taxonomy_' . $name;

  // @todo Remove when stable.
  if (!isset($defaults[$name])) {
    trigger_error(t('Default variable for %variable not found.', array('%variable' => $name)));
  }

  return variable_get($name, isset($default) || !isset($defaults[$name]) ? $default : $defaults[$name]);
}