// JavaScript Document


function xmlhttpPost() 
{
    var xmlHttpReq = false;
    var self = this;
    
	// Mozilla/Safari
    if (window.XMLHttpRequest) 
	{
        self.xmlHttpReq = new XMLHttpRequest();
    }
    else if (window.ActiveXObject)     // IE
	{
        self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
    }
	else
	{
		return false;
	}
	
	return self;
}

function dbQuery()
{
	ajaxPost = xmlhttpPost();
	if(!ajaxPost)
	{
		alert('Error setting up XMLHttpRequest');
	}

    ajaxPost.xmlHttpReq.open('POST', 'release_filter_query.php', true);
    ajaxPost.xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    
	ajaxPost.xmlHttpReq.onreadystatechange = function() 
	{
        if (ajaxPost.xmlHttpReq.readyState == 4) 
		{
            updatedbquery(ajaxPost.xmlHttpReq.responseText);
        }
    }
    
	ajaxPost.xmlHttpReq.send(getquerystring());
}


function getquerystring() 
{
    var artist = document.filter_releases.artist.value;
    var format = document.filter_releases.format.value;
    var mode = document.filter_releases.mode.value;	
	
	var checked_format;
		
    qstr = 'artist=' + escape(artist) + '&' + 'format=' + escape(format) + '&' + 'mode=' + escape(mode);
    return qstr;
}

function updatedbquery(str)
{
    document.getElementById("filter_results").innerHTML = str;
}