<?php
// $Id: taxonomy_other.module,v 1.6 2009-12-22 23:42:00 rellis Exp $

/**
 * @file
 * Add '- Other -' to taxonomy select lists.
 */

/**
 * Implementation of hook_help().
 */
function taxonomy_other_help($path, $arg) {
  switch ($path) {
    case 'admin/help#taxonomy_other':

      // Filter README.txt to get help text.
      $help = filter_filter('process', 1, NULL, file_get_contents(dirname(__FILE__) . "/README.txt") );

      // Make admin/... strings into links.
      $help = preg_replace('#(admin/[\w/]+)#e', 'l("$1", "$1")', $help);
      $help = str_replace('admin/user/permissions"', 'admin/user/permissions#module-taxonomy_other"', $help);

      // Make '= Headline' into '<strong>Headline</strong>'
      $help = preg_replace('#^<p>=\s(.*?)</p>$#m', '<p><strong>$1</strong></p>', $help);

      // Make '*' bulleted list items into an HTML unordered list.
      $help = preg_replace('#<p>\*\s(.*?)</p>#s', '<li><p>$1</p></li>', $help);
      $help = preg_replace('#<li>#', '<ul><li>', $help, 1);
      $help = strrev(preg_replace(strrev('#</li>#'), strrev('</li>'), strrev($help), 1));

      return $help;
  }
}

/**
 * Implementation of hook_perm().
 */
function taxonomy_other_perm() {
  return array('add other terms');
}

/**
 * Implementation of hook_form_{taxonomy_form_vocabulary}_alter().
 */
function taxonomy_other_form_taxonomy_form_vocabulary_alter (&$form, &$form_state) {

  // Add new taxonomy_other vocabulary setting.
  $form['settings']['taxonomy_other'] = array(
    '#type' => 'checkbox',
    '#title' => t('Users can add terms'),
    '#default_value' => (int) in_array($form['vid']['#value'], variable_get('taxonomy_other_vids', array())),
    '#description' => t('Allows users to add new terms. Adds \'- Other -\' to select lists.'),
  );

  // Add setting to hide taxonomy_other-created terms.
  $form['settings']['taxonomy_other_show_terms'] = array(
    '#type' => 'checkbox',
    '#title' => t('Show user-added terms'),
    '#default_value' => (int) in_array($form['vid']['#value'], variable_get('taxonomy_other_show_terms_vids', array())),
    '#description' => t('Allows users to select terms added by other users.'),
  );

  // Sink 'weight' to the bottom of the settings.
  if (!isset($form['settings']['weight']['#weight'])) {
    $form['settings']['weight']['#weight'] = 1;
  }

  // Register form callbacks.
  $form['#validate'][] = 'taxonomy_other_taxonomy_form_vocabulary_validate';
  $form['#submit'][]   = 'taxonomy_other_taxonomy_form_vocabulary_submit';
}

/**
 * Validate callback for 'taxonomy_form_vocabulary'.
 */
function taxonomy_other_taxonomy_form_vocabulary_validate($form, &$form_state) {
  // Don't allow both 'Multiple select' and taxonomy_other.
  if (!empty($form_state['values']['multiple']) && !empty($form_state['values']['taxonomy_other'])) {
    form_set_error('taxonomy_other', t('Sorry, %mtitle and %ttitle cannot both be checked.',
      array('%mtitle' => $form['settings']['multiple']['#title'], '%ttitle' => $form['settings']['taxonomy_other']['#title'])));
    $form_state['values']['taxonomy_other'] = 0;
    $form_state['rebuild'] = true;
  }
}

/**
 * Submit callback for 'taxonomy_form_vocabulary'.
 * Saves settings to variables 'taxonomy_other_vids' and 'taxonomy_other_show_terms_vids'.
 */
function taxonomy_other_taxonomy_form_vocabulary_submit($form, &$form_state) {
  $vid = $form_state['values']['vid'];
  foreach (array('taxonomy_other', 'taxonomy_other_show_terms') as $setting) {
    $vids = variable_get($setting . '_vids', array());
    if (!empty($form_state['values'][$setting])) {
      $vids[$vid] = $vid;
    }
    else {
      unset($vids[$vid]);
    }
    variable_set($setting . '_vids', $vids);
  }
}

/**
 * Implementation of hook_form_alter().
*/
function taxonomy_other_form_alter(&$form, &$form_state, $form_id) {

  // Alter node forms.
  if ($form_id == $form['type']['#value'] . '_node_form') {
    $new_fields = 0;

    // For taxonomy vocabularies that use taxonomy_other...
    foreach(variable_get('taxonomy_other_vids', array()) as $vid) {

      // Vocabulary in use on this form?
      if (isset($form['taxonomy'][$vid])) {

        // Hide terms?
        if (!in_array($vid, variable_get('taxonomy_other_show_terms_vids', array()))) {
          $hide = array_flip(taxonomy_other_get_tids($vid));
          if (isset($form['taxonomy'][$vid]['#default_value'][0])) {
            unset($hide[$form['taxonomy'][$vid]['#default_value'][0]]);
          }
          // Remove the options from the select list.
          foreach ($form['taxonomy'][$vid]['#options'] as $opt_key => $opt) {
            if (is_object($opt) && isset($opt->option) && is_array($opt->option)) {
              foreach (array_keys($opt->option) as $opt_tid) {
                if (isset($hide[$opt_tid])) {
                  unset($form['taxonomy'][$vid]['#options'][$opt_key]);
                }
              }
            }
          }
        }

        // For users with permissions, add '- Other -' select option and a text field for a new term.
        if (user_access('add other terms')) {

          // Add the select option.
          $form['taxonomy'][$vid]['#options'][] =  (object) array('option' => array('taxonomy_other' => t('- Other -')));

          // Add a specific weight for the select list, so we can make the text field follow immediately after.
          $form['taxonomy'][$vid]['#weight'] = $form['taxonomy'][$vid]['#weight'] += 0.1 * $vid;

          // Handle preview.
          if (!empty($form_state['clicked_button']['#post']['taxonomy']['taxonomy_other_' . $vid])) {
            $taxonomy_other = $form_state['clicked_button']['#post']['taxonomy']['taxonomy_other_' . $vid];
            $form['taxonomy'][$vid]['#default_value'] = 'taxonomy_other';
          }

          // Add the text field.
          $form['taxonomy']['taxonomy_other_' . $vid] = array(
            '#type' => 'textfield',
            '#size' => 128,
            '#title' => t('Other %title', array('%title' => $form['taxonomy'][$vid]['#title'])),
            '#id' => 'taxonomy-other-' . $vid,
            '#default_value' => empty($taxonomy_other) ? '' : $taxonomy_other,
            '#description' => t('Add your own category.'),
            '#weight' => $form['taxonomy'][$vid]['#weight'] + 0.01,
          );

          // Get any previously queued new term.
          if (!empty($form['nid']['#value'])) {
            if ($name = taxonomy_other_queue($form['nid']['#value'], $vid)) {
              $form['taxonomy']['taxonomy_other_' . $vid]['#default_value'] = $name;
              $form['taxonomy'][$vid]['#value'] = 'taxonomy_other';
            }
          }

          // Count.
          $new_fields++;
        }
      }
    }

    // If we've added fields, register the submit and validate callbacks and add javascript.
    if ($new_fields) {
      $form['#validate'][] = 'taxonomy_other_node_form_validate';
      $form['#submit'][]   = 'taxonomy_other_node_form_submit';
      drupal_add_js(drupal_get_path('module', 'taxonomy_other') . '/taxonomy_other.js');
    }
  }
}

/**
 * Validation callback for '*_node_form'.
 */
function taxonomy_other_node_form_validate(&$form, &$form_state) {

  // If a term is required and taxonomy_other is selected but empty,
  //  generate a form error like the form API would...
  foreach ($form_state['values']['taxonomy'] as $vid => $tid) {
    if ($tid == 'taxonomy_other' && !empty($form['taxonomy'][$vid]['#required']) 
          && empty($form_state['values']['taxonomy']['taxonomy_other_' . $vid])) {
      form_set_error('taxonomy][' . $vid, t('!name field is required.', array('!name' => $form['taxonomy'][$vid]['#title'])));
    }
  }

  // Re-add the javascript for cached forms.
  if (form_get_errors()) {
    drupal_add_js(drupal_get_path('module', 'taxonomy_other') . '/taxonomy_other.js');
  }
}

/**
 * Submit callback for '*_node_form'.
 */
function taxonomy_other_node_form_submit($form, &$form_state) {

  // Loop through through vocabularies with 'taxonomy_other' set.
  foreach(variable_get('taxonomy_other_vids', array()) as $vid) {

    // New term posted?
    if (!empty($form_state['values']['taxonomy']['taxonomy_other_' . $vid])) {
      $term = array();
      $name = $form_state['values']['taxonomy']['taxonomy_other_' . $vid];

      // Queue the term for creation.
      if (empty($term)) {
        taxonomy_other_queue('', $vid, $name);
      }

      // Remove our taxonomy_other form value so it doesn't interfere with the taxonomy module.
      unset($form_state['values']['taxonomy']['taxonomy_other_' . $vid]);

      // For created terms, let taxonomy module handle term<->node associations.
      if ($term['tid']) {
        $form_state['values']['taxonomy'][$vid] = $term['tid'];
      }
      else {
        // Hide queued terms from the taxonomy module.
        unset($form_state['values']['taxonomy'][$vid]);
      }
    }
  }
}

/**
 * Keep track of new terms for unpublished nodes.
 *
 * - If $nid, $vid and $name are specified, save the term in the database queue.
 * - If $vid and $name are specified, save the term in the static queue.
 * - If $nid and $vid are specified, retrieve the term from the queue.
 * - If only $nid is specified, retrieve all the terms from the static and database queue.
 *
 * @param $nid
 *   Node id.
 * @param $vid
 *   Vocabulary id.
 * @param $name
 *   Name of the new term.
 *
 * @return
 *   Depends on the arguments.
 */
function taxonomy_other_queue($nid = '', $vid = '', $name = '') {
  static $q = array();

  if ($nid && $vid && $name) {
    db_query("DELETE FROM {taxonomy_other_queue} WHERE nid = %d AND vid = %d", $nid, $vid);
    return db_query("INSERT INTO {taxonomy_other_queue} (nid, vid, name) values(%d, %d, '%s')", $nid, $vid, $name);
  }
  elseif ($vid && $name) {
    $q[$vid] = $name;
  }
  elseif ($nid && $vid) {
    return db_result(db_query("SELECT name FROM {taxonomy_other_queue} WHERE nid = %d AND vid = %d", $nid, $vid));
  }
  elseif ($nid) {
    $result = db_query("SELECT vid, name FROM {taxonomy_other_queue} WHERE nid = %d", $nid);
    while ($term = db_fetch_object($result)) {
      if (!isset($q[$term->vid])) {
        $q[$term->vid] = $term->name;
      }
    }
    return $q;
  }
}

/**
 * Remove queued terms for a node.
 */
function taxonomy_other_dequeue($nid) {
  return db_query("DELETE FROM {taxonomy_other_queue} WHERE nid = %d", $nid);
}

/**
 * Create the term and assign it to the node.
 */
function taxonomy_other_save(&$node, $vid, $name) {

  // Check for duplicates because taxonomy_save_term() doesn't.
  foreach (taxonomy_get_term_by_name($name) as $t) {
    if ($vid == $t->vid) {
       $term = (array) $t;
       break;
    }
  }

  // Not a duplicate?
  if (empty($term)) {

    // Create term.
    $term = array('vid' => $vid, 'name' => $name, 'tid' => 0, 'description' => '', 'weight' => 0);
    taxonomy_save_term($term);

    // Remember this module created it.
    $record = (object) array('tid' => $term['tid']);
    drupal_write_record('taxonomy_other_term', $record);
  }

  // Assign to node.
  $node->taxonomy[$vid] = $term['tid'];
  taxonomy_node_save($node, $node->taxonomy);

  return $term;
}

/**
 * Get the terms for a vocabulary that were created by this module.
 *
 * @param $vid
 *   A vocabulary id.
 * @return
 *   An array of terms.
 */
function taxonomy_other_get_tids($vid) {
  $tids = array();
  $result = db_query("SELECT t.tid FROM {term_data} t INNER JOIN {taxonomy_other_term} ot ON (t.tid = ot.tid) WHERE t.vid = %d", $vid);
  while ($term = db_fetch_object($result)) {
    $tids[] = $term->tid;
  }
  return $tids;
}

/**
 * Implementation of hook_nodeapi().
 */
function taxonomy_other_nodeapi(&$node, $op) {
  if ($op == 'insert' || $op == 'update') {
    foreach (taxonomy_other_queue($node->nid) as $vid => $name) {
      if ($node->status) {
        taxonomy_other_save($node, $vid, $name);
        taxonomy_other_dequeue($node->nid);
      }
      else { // Not published, just queue...
        taxonomy_other_queue($node->nid, $vid, $name); // Add to db queue.
      }
    }
  }
  elseif ($op == 'delete') {
    taxonomy_other_dequeue($node->nid); // Delete from db queue.
  }
}

/**
 * Implementation of hook_taxonomy().
 */
function taxonomy_other_taxonomy($op, $type, $array) {
  if ($op == 'delete') {
    if ($type == 'vocabulary') {
      $terms = taxonomy_other_get_tids($array['vid']);
      if (!empty($terms)) {
        $d = implode(',', array_pad(array(), count($terms), '%d'));
        db_query("DELETE FROM {taxonomy_other_term} WHERE tid IN (" . $d . ")", $terms);
      }
    }
    elseif ($type == 'term') {
      db_query("DELETE FROM {taxonomy_other_term} WHERE tid = '%d'", $array['tid']);
    }
  }
}