var chart_gmusic = 1;
var chart_hot100 = 1;

function changechart(chart, next){
	//$('.alert').append(chart_gmusic+'/'+chart_hot100);
	var q;
	if(chart == 'gmusic')
		q = chart_gmusic;
	else if(chart == 'hot100')
		q = chart_hot100;

	query(q, chart, next, 20);
}

function query(query, chart, next, rank_max, callback){
	/*$('#questionnaire').fadeOut();
	var preresult = $('#result > tbody').html();
	//var preresult;
	$('#result > tbody').html("<tr><td colspan=\"6\"><img src=\"image/loading.gif\" border=\"0\" /><br />Loading...</td></tr>");
	
	var year = $('#select_exam').val();
	var query;
	
	if (type=='name')
		query = $('#name').val();
	else if (type=='number')
		query = $('#number').val();
	else if (type=='senior')
		query = $('#select_highschool').val();
	else if (type=='dept')
		query = $('#select_dept').val();
	else
		return;
	*/
	
	if(next)
			query--;
		else
			query++;
		
	if(chart == 'gmusic'){
		$.post("/page/chart/ajax_gmusic.php", { "week": query, "rank_max": rank_max },
			function(records){
				load_result(records, chart, next, callback);
			}, "json"
		);
	}else if(chart == 'hot100'){
		$.post("/page/chart/ajax_hot100.php", { "week": query, "rank_max": rank_max },
			function(records){
				load_result(records, chart, next, callback);
			}, "json"
		);
	}
}

function load_result(records, chart, next, callback){
	if(records['date']==null || records['date']=='undefined'){
		//$('.alert').append('no data');
		return;
	}else{
		if(chart == 'gmusic'){
			if(next)
				chart_gmusic--;
			else
				chart_gmusic++;
		}else if(chart == 'hot100'){
			if(next)
				chart_hot100--;
			else
				chart_hot100++;
		}
	}
	$('.'+chart+' .chartdate').html(records['date']);
	var buf = '';
	/*if(chart == 'hot100')
		buf += '<table><tr><td>名次</td><td>歌手</td><td>單曲</td></tr>';*/
	buf += '<table class="chart_table">';
	for (var i=0; i < records['data'].length; i++) {
		if(chart == 'gmusic'){
			buf += '<tr><td><div class="chart_rank">'+records['data'][i].rank+'</div><div class="chart_icon">';
			
			if(records['data'][i].last == 0)
				buf += '<img src="/image/chart/new.png" alt="new">';
			else if(records['data'][i].rank < records['data'][i].last)
				buf += '<img src="/image/chart/up.png" alt="up">';
			else if(records['data'][i].rank > records['data'][i].last)
				buf += '<img src="/image/chart/down.png" alt="down">';
			else
				buf += '<img src="/image/chart/stay.png" alt="stay">';
			
			buf += '</div></td><td><div class="chart_avatar"><img src="http://www.g-music.com.tw'+records['data'][i].image+'" alt="avatar" width="100" /></div></td><td><div class="chart_info"><span class="chart_title">'+records['data'][i].album+'</span><br /><span class="chart_desc">'+records['data'][i].artist+'</span></div></td></tr>';
		}
		else if(chart == 'hot100'){
			buf += '<tr><td><div class="chart_rank">'+records['data'][i].rank+'</div><div class="chart_icon">';

			if(records['data'][i].last == 0)
				buf += '<img src="/image/chart/new.png" alt="new">';
			else if(records['data'][i].rank < records['data'][i].last)
				buf += '<img src="/image/chart/up.png" alt="up">';
			else if(records['data'][i].rank > records['data'][i].last)
				buf += '<img src="/image/chart/down.png" alt="down">';
			else
				buf += '<img src="/image/chart/stay.png" alt="stay">';

			buf += '</div></td><td><div class="chart_avatar"><img src="http://www.billboard.com'+records['data'][i].image+'" alt="avatar" width="100" /></div></td><td><div class="chart_info"><span class="chart_title">'+records['data'][i].title+'</span><br /><span class="chart_desc">'+records['data'][i].artist+'</span></div></td></tr>';
		}
	}
	buf += '</table>';
	/*if(chart == 'hot100')
		buf += '</table>';*/
	
	$('.'+chart+' .chartdata').html(buf);
	
	//alert($('.'+chart+' .chartdata').html());
	//buf += '</div>';
	//alert(records['date']);
	if(callback!=null)
		callback();
	//$('.'+chart+' .chartdata').fadeIn('slow');
	return;
}