/*
画像リストのスクロール処理
*/
var frame_obj;
var content_obj;

var frame_width;
var frame_offset;
var content_width;

var timer_left;
var timer_right;
var timer_auto;

var scroll_step;
var is_moving_left = false;
var is_moving_right = false;

var firefox_evt;

function init_event(){
	frame_obj = $("image_frame");
	frame_width = parseInt(frame_obj.style.width);
	frame_offset = get_offset(frame_obj);
	content_obj = $("image_content");
	content_width = parseInt(content_obj.style.width);
	
//	frame_obj.onmousemove = function(evt){
//		start_scroll(evt);
//	}
//	frame_obj.onmouseout = function(evt){
//		stop_scroll(evt);
//	}
	timer_auto = setInterval("auto_scroll()",50);	//	自動スクロール開始

	if (!window.event) {
		window.onmousemove = getMouseXY;
	}
}


function getMouseXY(evt){
	firefox_evt = evt;
}


//	スクロール開始
function start_scroll(evt){
	if(timer_auto){
		clearInterval(timer_auto);
	}
	var page_offset = (window.pageXOffset) ? pageXOffset: get_body_element().scrollLeft;
	var mouse_x = window.event ? event.clientX : (firefox_evt.clientX ? firefox_evt.clientX : 0);
	var mouse_pos = mouse_x - frame_offset - page_offset;
	var hit_area_left = (frame_width - 10) / 2;	//	10は非反応領域幅
	var hit_area_right = (frame_width + 10) / 2;	//	10は非反応領域幅
	
	if(mouse_pos > hit_area_right){
//		scroll_step = (mouse_pos - hit_area_right) / hit_area_right * 5;	//	5は最大増幅値
		scroll_step = 3;	//スクロール速度
		if(timer_right){
			clearTimeout(timer_right);
		}
		if(!is_moving_left){
			scroll_left();
		}
	} else if(mouse_pos < hit_area_left){
//		scroll_step = (hit_area_left - mouse_pos) / hit_area_left * 5;	//	5は最大増幅値
		scroll_step = 3;	//スクロール速度
		if(timer_left){
			clearTimeout(timer_left);
		}
		if(!is_moving_right){
			scroll_right();
		}
	}
	else {
		scrollspeed = 0;
	}
}
//	スクロール停止
function stop_scroll(evt){
	if(timer_left){
		clearTimeout(timer_left);
	}
	if(timer_right){
		clearTimeout(timer_right);
	}
	is_moving_right = false;
	is_moving_left = false;
}
//	自動スクロール
function auto_scroll(){
	if(parseInt(content_obj.style.left) > (frame_width - content_width)){
		content_obj.style.left = parseInt(content_obj.style.left) - 1 + "px";
		is_moving_right = true;
	} else {
		clearInterval(timer_auto);
		is_moving_right = false;
	}
}
//	右へクスロール
function scroll_right(){
	is_moving_right = true;
	if(parseInt(content_obj.style.left) < 0){
		content_obj.style.left = parseInt(content_obj.style.left) + scroll_step + "px";
	}
	timer_right = setTimeout("scroll_right()",10);
}
//	左へスクロール
function scroll_left(){
	is_moving_left = true;
	if(parseInt(content_obj.style.left) > (frame_width - content_width)){
		content_obj.style.left = parseInt(content_obj.style.left) - scroll_step + "px";
	}
	timer_left = setTimeout("scroll_left()",10);
}

function get_offset(obj){
	var offset = obj.offsetLeft;
	var parent_obj = obj.offsetParent;
	while (parent_obj != null){
		offset += parent_obj.offsetLeft;
		parent_obj = parent_obj.offsetParent;
	}
	return offset;
}
function get_body_element(){
	return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body;
}