<?php
class SearchHistoryService {
    var $db;
    var $tablename;
    var $sizeSearchHistory;

    function &getInstance(&$db) {
        static $instance;
        if (!isset($instance))
            $instance =& new SearchHistoryService($db);
        return $instance;
    }

    function SearchHistoryService(& $db) {
        $this->db =& $db;
        $this->tablename = $GLOBALS['tableprefix'] .'searchhistory';
	if(isset($GLOBALS['sizeSearchHistory'])) {
            $this->sizeSearchHistory = $GLOBALS['sizeSearchHistory'];
	} else {
	    $this->sizeSearchHistory = 10;
	}
    }

    function addSearch($terms, $range, $nbResults, $uId=0) {
	if(strlen($terms) == 0) {
	    return false;
	}
        $datetime = gmdate('Y-m-d H:i:s', time());

	//Insert values
	$values = array('shTerms'=>$terms, 'shRange'=>$range, 'shDatetime'=>$datetime, 'shNbResults'=>$nbResults, 'uId'=>$uId);
	$sql = 'INSERT INTO '. $this->getTableName() .' '. $this->db->sql_build_array('INSERT', $values);
        $this->db->sql_transaction('begin');
        if (!($dbresult = & $this->db->sql_query($sql))) {
            $this->db->sql_transaction('rollback');
            message_die(GENERAL_ERROR, 'Could not insert search history', '', __LINE__, __FILE__, $sql, $this->db);
            return false;
        }

	if($this->sizeSearchHistory != -1 && 
		$this->countSearches() > $this->sizeSearchHistory) {
	    $this->deleteOldestSearch();
	}
    }

    function getAllSearches($range = NULL, $uId = NULL, $nb = NULL, $start = NULL, $distinct = false, $withResults = false) {
	$sql = 'SELECT DISTINCT(shTerms), shId, shRange, shNbResults, shDatetime, uId';
	$sql.= ' FROM '. $this->getTableName();
	$sql.= ' WHERE 1=1';
	if($range != NULL) {
	    $sql.= ' AND shRange = "'.$range.'"';
	} else {
	    $sql.= ' AND shRange = "all"';
	}
	if($uId != NULL) {
	    $sql.= ' AND uId = '.$uId;
	}
	if($withResults = true) {
	    $sql.= ' AND shNbResults > 0';
	}
	if($distinct) {
	    $sql.= ' GROUP BY shTerms';
	}
	$sql.= ' ORDER BY shId DESC';

        if (!($dbresult = & $this->db->sql_query_limit($sql, $nb, $start))) {
            message_die(GENERAL_ERROR, 'Could not get searches', '', __LINE__, __FILE__, $sql, $this->db);
            return false;
        }

        $searches = array();
        while ($row = & $this->db->sql_fetchrow($dbresult)) {
            $searches[] = $row;
        }
        return $searches;
    }

    function countSearches() {
	$sql = 'SELECT COUNT(*) AS `total` FROM '. $this->getTableName();
        if (!($result = & $this->db->sql_query($sql)) || (!($row = & $this->db->sql_fetchrow($result)))) {
            message_die(GENERAL_ERROR, 'Could not get total searches', '', __LINE__, __FILE__, $sql, $this->db);
            return false;
        }

	return $row['total'];
    }

    /* This function allows to limit the number of saved searches
       by deleting the oldest one */
    function deleteOldestSearch() {
	$sql = 'DELETE FROM '.$this->getTableName();
	$sql.= ' ORDER BY shId ASC LIMIT 1';  // warning: here the limit is important

        $this->db->sql_transaction('begin');
        if (!($dbresult = & $this->db->sql_query($sql))) {
            $this->db->sql_transaction('rollback');
            message_die(GENERAL_ERROR, 'Could not delete bookmarks', '', __LINE__, __FILE__, $query, $this->db);
            return false;
        }
    }

    function deleteAll() {
	$query = 'TRUNCATE TABLE `'. $this->getTableName() .'`';
	$this->db->sql_query($query);
    }   

    // Properties
    function getTableName()       { return $this->tablename; }
    function setTableName($value) { $this->tablename = $value; }
}
?>
