<?php

/*
Part of the auto-tag plugin for wordpress

Copyright 2009-2012 Jonathan Foucher

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

*/

class AutoTag {

    protected $rmtags;
    protected $addtags;

    public static function forbidden_tag($forbidden,$tag)
    {
    if (is_array($forbidden) && !empty($forbidden)){
      foreach($forbidden as $forbid){
        if ($forbid !='')
          if(strpos(strtolower($tag), strtolower($forbid))!==false)
            return true;
      }
    }
    return false;
  }

  function auto_tag_yahoo($content, $num, $remove_tags)
  {

    $tags = array();

    try {

      $response = wp_remote_get( 'http://query.yahooapis.com/v1/public/yql?q='
        . urlencode( sprintf('select * from contentanalysis.analyze where text = "%s"',
            utf8_decode(strip_tags($content)) ) )
        . '&format=json&diagnostics=true&callback=' );

      $data = wp_remote_retrieve_body( $response );

      if ( empty($data) ) {
        throw new ErrorException( 'No response from remote.' );
      }

      $json = json_decode( $data );

      if ( ! isset($json->query->results->entities->entity) ) {
        throw new ErrorException( 'No tags returned.' );
      }

      foreach ( $json->query->results->entities->entity as $entity ) {
        $tag = $entity->text->content;
        if ( self::forbidden_tag( $remove_tags, $tag ) OR strlen( $tag ) < 3 ) continue;
        $tags[] = $tag;
      }

      if ( count($tags) > $num ) {
        $tags = array_slice( $tags, 0, $num );
      }

    } catch (ErrorException $e) {

    }

    return join(',', $tags);
  }


  public function __construct()
  {
    add_action('save_post', array($this, 'tag_posts'), 1);
    /** feedwordpress **/
    if ( function_exists( 'is_syndicated' ) ) {
      add_action('post_syndicated_item', array($this, 'tag_posts'), 1 );
    }
  }

  public static function trim_tags(&$item, $k)
    {
    $item = trim($item);
  }

    public function remove_tags($tag)
    {
        if(in_array($tag, explode(',', $this->rmtags))) {
            return false;
        }
        return true;
    }

  public function tag_posts($postid)
  {
        $removed_tags = @filter_input(INPUT_POST, 'auto_tag_removed_tags', FILTER_SANITIZE_STRING);
        $removed_tag = @filter_input(INPUT_POST, 'auto_tag_removed_tag', FILTER_SANITIZE_STRING);
        $added_tags = @filter_var( $_POST['tax_input']['post_tag'], FILTER_SANITIZE_STRING);
        $added_tag = @filter_var($_POST['new_tag']['post_tag'], FILTER_SANITIZE_STRING);
        $disable = @filter_var($_POST['autotag_disabled_on_post'], FILTER_SANITIZE_NUMBER_INT);

        $this->rmtags = $removed_tags . ($removed_tag ? ',' . $removed_tag : '');
        $this->addtags = $added_tags . ($added_tag ? ',' . $added_tag : '');

        $removed = explode(',', strtolower(get_option('autotag_remove_tags')) .
        ($this->rmtags ? ',' . $this->rmtags : ''));

        update_post_meta($postid, '_auto_tag_removed_tags', $this->rmtags);
        update_post_meta($postid, '_auto_tag_disabled', $disable);

        if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
            return;

        $post = get_post($postid, ARRAY_A);

        if ( 'page' == $post['post_type'] ) {
            if (!current_user_can( 'edit_page', $postid ) || !get_option('autotag_tag_pages'))
                return;
        }else{
            if (!current_user_can( 'edit_post', $postid ) || !get_option('autotag_tag_posts'))
                return;
        }

        $tags = array_merge(
            wp_get_post_tags($postid, array( 'fields' => 'name' )),
            explode(',', $this->addtags)
        );

        $tags = array_filter($tags, array($this, 'remove_tags'));
        $old_tags = join(',', $tags);
        $keywords = $old_tags;
        if(!$disable) {
            $yahoo_num = (get_option('autotag_number') ? get_option('autotag_number') : 5);
            array_walk($removed, 'AutoTag::trim_tags');

            $content = $post['post_title']." ".$post['post_content'];

            $num_tags_to_add = $yahoo_num - count($tags);
            $old_tags = join(',', $tags);
            $keywords = AutoTag::auto_tag_yahoo($content, $num_tags_to_add, $removed).($old_tags ? ','.$old_tags : '');
        }

        remove_action('save_post', array($this, 'tag_posts'));

        wp_set_post_tags( $postid, $keywords, false);
  }

}