<?php
/*
  Copyright (C) 2008 by Phase2 Technology.
  Author(s): Frank Febbraro, Irakli Nadareishvili

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License.
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY. See the LICENSE.txt file for more details.

  $Id: calais_tagmods.module,v 1.1.4.3 2008-05-13 14:19:03 febbraro Exp $
*/

/**
 * Implementation of hook_menu().
 */
function calais_tagmods_menu($may_cache) {
  $items = array();
  if ($may_cache) {
    $items[] = array(
      'path' => 'admin/settings/calais/calais-tagmods',
      'title' => t('Calais Tag Modifications'),
      'description' => t('Configurations for Calais Tag Modifications'),
      'callback' => 'drupal_get_form',
      'callback arguments' => array('calais_tagmods_settings'),
      'type' => MENU_LOCAL_TASK,
    );
  }
  return $items;
}

/**
 * Build the admin settings form.
 */
function calais_tagmods_settings() {
  $form = array();
  
  $form['calais_tag_blacklist'] = array(
    '#type' => 'textarea',
    '#title' => t('Calais Blacklist'),
    '#default_value' => variable_get('calais_tag_blacklist', NULL),
    '#rows' => 6,
    '#description' => t('A comma-separated list of terms to be removed from the Calais response. Example: funny, bungee jumping, "Company, Inc.".'),
  );
  
  $form['calais_tag_substitution'] = array(
    '#type' => 'textarea',
    '#title' => t('Calais Substitutions'),
    '#default_value' => variable_get('calais_tag_substitution', NULL),
    '#rows' => 6,
    '#description' => t('A list of substitutions. One option per line. Key-value pairs may be entered separated by an equals. i.e. Calais Term=Some Local Substitution'),
  );
  
  $form = system_settings_form($form);
  return $form;
}

/**
 * Implementation of hook_calais_preprocess.
 *
 * Make sure that a vocabulary exists for all entities returned, if not, create it.
 */
function calais_tagmods_calais_preprocess($node, &$keywords) {
  _calais_tagmods_apply_blacklist(&$keywords);
  _calais_tagmods_apply_substitutions(&$keywords);
}

/**
 * Filter out unwanted keywords
 */
function _calais_tagmods_apply_blacklist(&$keywords) {  
  $bl_string = variable_get('calais_tag_blacklist', NULL);
  $blacklist = calais_explode_tags($bl_string);

  foreach ($keywords as $cat => $terms) {
    $diff = array_diff($terms, $blacklist);
    $keywords->$cat = array_values($diff);
  }
}

/**
 * Substitute keywords with others.
 */
function _calais_tagmods_apply_substitutions(&$keywords) {

  $sub_string = variable_get('calais_tag_substitution', NULL);
  $rows = explode("\n", $sub_string);
  $subs = array();
  foreach ($rows as $row) {
    $row = trim($row);
    if (!empty($row)) {
      preg_match('/^(.*)=(.*)$/', $row, $matches);
      $subs[$matches[1]] = $matches[2];
    }
  }

  foreach ($keywords as $cat => $terms) {
    foreach ($terms as $key => $term) {
      if (array_key_exists($term, $subs)) {
        $terms[$key] = $subs[$term];
        $keywords->$cat = $terms;
      }
    }
  }
}