var dragElement = null;
var startX = null;
var mouseShift = 0;
var sliderTopY = 0;
var slideBarX = 0;
var id;

var phrases = new Array();

function preparePhrases() {
	var args = preparePhrases.arguments;
	var i;
	for(i = 0; i < args.length; i++) {
		phrases[i] = document.getElementById(args[i]);
	}
}

function hideAllPhrases() {
	for(i = 0; i < phrases.length; i++) {
		phrases[i].style.display = 'none';
	}
}

function drag(event) {
	if(!event) event = window.event; 
	var slider = document.getElementById('slider');
	dragElement = true;
	startX = slider.offsetLeft;
	var forShift = 0;
	while(slider != null) { forShift += slider.offsetLeft; slider = slider.offsetParent; }
	mouseShift = event.clientX + document.body.scrollLeft - forShift;
}

document.onmouseup=function() {
	dragElement = null;
	startX = null;
}

document.onmousedown=function() {
	if(dragElement) return false;
	return true;
}

document.onselectstart=function() {
	if(dragElement) return false;
	return true;
}

var mouseX = 0;
var mouseY = 0;

document.onmousemove=function(event) {
	if(!event) event = window.event; 
	sliderTopY = 0;
	slideBarX=0;
	var slideBar = document.getElementById('slidebar');
	var obj = slideBar;
	while(obj != null) { slideBarX += obj.offsetLeft; sliderTopY += obj.offsetTop; obj = obj.offsetParent; }
	var slider = document.getElementById('slider');

    mouseX = event.clientX + document.documentElement.scrollLeft;
    mouseY = event.clientY + document.documentElement.scrollTop;
	if (dragElement) {
		document.body.style.cursor = 'pointer';
		if((mouseY > (sliderTopY - 40)) && (mouseY < (sliderTopY + 63))) {
			if(mouseX - mouseShift < slideBarX) { slider.style.left = "0px"; }
			else if((mouseX - mouseShift) > (slideBar.offsetWidth + slideBarX - 24)) slider.style.left = slideBar.offsetWidth - 24 + "px";
			else slider.style.left = mouseX - slideBarX - mouseShift + "px";
		}
		id=Math.floor(slider.offsetLeft/(slideBar.offsetWidth/phrases.length));
		if(id==phrases.length) id--;
		if(phrases[id].style.display!='block') {
			hideAllPhrases();
			phrases[id].style.display='block';
		}
	} else {
		document.body.style.cursor = 'auto';
	}
}