<?php
/* vim:set tabstop=8 softtabstop=8 shiftwidth=8 noexpandtab: */
/*
 * Search Library
 *
 * This library handles all the searching!
 *
 * PHP version 5
 *
 * LICENSE: GNU General Public License, version 2 (GPLv2)
 * Copyright (c) 2001 - 2011 Ampache.org All Rights Reserved
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License v2
 * as published by the Free Software Foundation.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

/**
 * run_search
 * this function actually runs the search, and returns an array of the results. Unlike the previous
 * function it does not do the display work its self.
 */
function run_search($data) {

	/* Create an array of the object we need to search on */
	foreach ($data as $key=>$value) {
		/* Get the first two chars to check
		 * and see if it's s_
		 */
		$prefix = substr($key,0,2);
		$value = trim($value);

		if ($prefix == 's_' AND strlen($value)) {
			$true_name = substr($key,2,strlen($key));
			$search[$true_name] = Dba::escape($value);
		}

	} // end foreach

	/* Figure out if they want a AND based search or a OR based search */
	switch($_REQUEST['operator']) {
		case 'or':
			$operator = 'OR';
		break;
		default:
			$operator = 'AND';
		break;
	} // end switch on operator

	/* Figure out what type of method they would like to use, exact or fuzzy */
	switch($_REQUEST['method']) {
		case 'fuzzy':
			$method = "LIKE '%__%'";
		break;
		default:
			$method = "= '__'";
		break;
	} // end switch on method

	$limit = intval($_REQUEST['limit']);

	/* Switch, and run the correct function */
	switch($_REQUEST['object_type']) {
		case 'artist':
		case 'album':
		case 'song':
			$function_name = 'search_' . $_REQUEST['object_type'];
			if (function_exists($function_name)) {
				$results = call_user_func($function_name,$search,$operator,$method,$limit);
				return $results;
			}
                break;
                default:
			$results = search_song($search,$operator,$method,$limit);
			return $results;
		break;
	} // end switch

	return array();

} // run_search

/**
 * search_song
 * This function deals specificly with returning song object for the run_search
 * function, it assumes that our root table is songs
 * @package Search
 * @catagory Search
 */
function search_song($data,$operator,$method,$limit) {

	/* Generate BASE SQL */

	$where_sql 	= '';
	$table_sql	= '';
	$group_sql 	= ' GROUP BY';
	$select_sql	= ',';
	$field_sql  = '';
	$order_sql = '';

	if ($limit > 0) {
		$limit_sql = " LIMIT $limit";
	}

	foreach ($data as $type=>$value) {

		/* Create correct Value statement based on method */

		$value_string = str_replace("__",$value,$method);

		switch ($type) {
			case 'all':
				$additional_soundex = false;

				if (!(strpos($value, '-'))) // if we want a fuzzier search
					$additional_soundex = true;

				$where_sql = "( MATCH (`artist2`.`name`, `album2`.`name`, `song`.`title`) AGAINST ('$value' IN BOOLEAN MODE)";

				if ($additional_soundex) {
					$where_sql.= " OR `artist2`.`name` SOUNDS LIKE '$value'";
					$where_sql.= " OR `album2`.`name` SOUNDS LIKE '$value'";
					$where_sql.= " OR `song`.`title` SOUNDS LIKE '$value' ";
				}
				$where_sql .= ") $operator";

				$table_sql = " LEFT JOIN `album` as `album2` ON `song`.`album`=`album2`.`id`";
				$table_sql.= " LEFT JOIN `artist` AS `artist2` ON `song`.`artist`=`artist2`.`id`";

				$order_sql = " ORDER BY";

				$order_sql.= " MATCH (`artist2`.`name`) AGAINST ('$value' IN BOOLEAN MODE)";
				if ($additional_soundex) $order_sql.= " + (SOUNDEX(`artist2`.`name`)=SOUNDEX('$value')) DESC,"; else $order_sql.= " DESC,";

				$order_sql.= " MATCH (`album2`.`name`) AGAINST ('$value' IN BOOLEAN MODE)";
				if ($additional_soundex) $order_sql.= " + (SOUNDEX(`album2`.`name`)=SOUNDEX('$value')) DESC,"; else $order_sql.= " DESC,";

				$order_sql.= " MATCH (`song`.`title`) AGAINST ('$value' IN BOOLEAN MODE)";
				if ($additional_soundex) $order_sql.= " + (SOUNDEX(`song`.`title`)=SOUNDEX('$value')) DESC,"; else $order_sql.= " DESC,";

				$order_sql.= " `artist2`.`name`,";
				$order_sql.= " `album2`.`name`,";
				$order_sql.= " `song`.`track`,";
				$order_sql.= " `song`.`title`";
			break;
			case 'title':
				$where_sql .= " `song`.`title` $value_string $operator";
			break;
			case 'album':
				$where_sql .= " `album`.`name` $value_string $operator";
				$table_sql .= " LEFT JOIN `album` ON `song`.`album`=`album`.`id`";
			break;
			case 'artist':
				$where_sql .= " `artist`.`name` $value_string $operator";
				$table_sql .= " LEFT JOIN `artist` ON `song`.`artist`=`artist`.`id` ";
			break;
			case 'year':
				if (empty($data["year2"]) && is_numeric($data["year"])) {
					$where_sql .= " `song`.`year` $value_string $operator";
				}
				elseif (!empty($data["year"]) && is_numeric($data["year"]) && !empty($data["year2"]) && is_numeric($data["year2"])) {
					$where_sql .= " (`song`.`year` BETWEEN ".$data["year"]." AND ".$data["year2"].") $operator";
				}
			break;
			case 'time':
				if (!empty($data['time2'])) {
					$where_sql .= " `song`.`time` <= " . Dba::escape(intval($data['time2'])*60) . " $operator";
				}
				if (!empty($data['time'])) {
					$where_sql .= " `song`.`time` >= " . Dba::escape(intval($data['time'])*60) . " $operator";
				}
			break;
			case 'filename':
				$where_sql .= " `song`.`file` $value_string $operator";
			break;
			case 'comment':
				$table_sql .= ' INNER JOIN `song_data` ON `song`.`id`=`song_data`.`song_id`';
				$where_sql .= " `song_data`.`comment` $value_string $operator";
			break;
			case 'played':
				/* This is a 0/1 value so bool it */
				$value = make_bool($value);
				$where_sql .= " `song`.`played` = '$value' $operator";
			break;
			case 'minbitrate':
				$value = intval($value);
				$where_sql .= " `song`.`bitrate` >= ('$value'*1000) $operator";
			break;
			case 'rating':
				$value = intval($value);
				$userid = $GLOBALS['user']->id;
				$rcomparison = '>=';
				if ($_REQUEST['s_rating_operator'] == '1') { 
					$rcomparison = '<=';
				}
				elseif ($_REQUEST['s_rating_operator'] == '2') {
					$rcomparison = '<=>';
				}
				// Complex SQL follows
				// We do a join on ratings from the table with a
				// preference for our own and fall back to the 
				// FLOORed average of everyone's rating if it's
				// a song we haven't rated.
				if ($operator == 'AND') {
					$table_sql .= ' INNER JOIN';
				}
				else {
					$table_sql .= ' LEFT JOIN';
				}
				$table_sql .= "	(SELECT `object_id`, `rating` FROM `rating` WHERE `object_type`='song' AND `user`='$userid'
					UNION
					SELECT `object_id`, FLOOR(AVG(`rating`)) AS 'rating' FROM `rating` 
						WHERE `object_type`='song' AND 
						`object_id` NOT IN (SELECT `object_id` FROM `rating` WHERE `object_type`='song' AND `user`='$userid')
						GROUP BY `object_id`
					) AS realrating ON `song`.`id` = `realrating`.`object_id`";

				$where_sql .= " `realrating`.`rating` $rcomparison '$value' $operator";
			break;
			case 'tag':

				// Fill it with one value to prevent sql error on no results
				$ids = array('0');

				$tag_sql = "SELECT `object_id` FROM `tag` LEFT JOIN `tag_map` ON `tag`.`id`=`tag_map`.`tag_id` " .
						"WHERE `tag_map`.`object_type`='song' AND `tag`.`name` $value_string ";
				$db_results = Dba::read($tag_sql);

				while ($row = Dba::fetch_assoc($db_results)) {
					$ids[] = $row['object_id'];
				}

				$where_sql  = " `song`.`id` IN (" . implode(',',$ids) . ") $operator";

			break;
			default:
				// Notzing!
			break;
		} // end switch on type


	} // foreach data

	/* Trim off the extra $method's and ,'s then combine the sucka! */
	$where_sql = rtrim($where_sql,$operator);
	$group_sql = rtrim($group_sql,',');
	$select_sql = rtrim($select_sql,',');

	if ($group_sql == ' GROUP BY') { $group_sql = ''; }

	$base_sql 	= "SELECT DISTINCT(`song`.`id`) $field_sql $select_sql FROM `song`";

	$sql = $base_sql . $table_sql . " WHERE " . $where_sql . $group_sql . $order_sql . $limit_sql;

	/**
	 * Because we might need this for Dynamic Playlist Action
	 * but we don't trust users to provide this store it in the
	 * session where they can't get to it!
	 */

	$_SESSION['userdata']['stored_search'] = $sql;

	$db_results = Dba::read($sql);

	$results = array();

	while ($row = Dba::fetch_assoc($db_results)) {
		$results[] = $row['id'];
	}

	return $results;

} // search_songs


?>