// fontsize.js

var sizeData = new Cookie(document, "fontSize");

if (!sizeData.load()) {
	if (!sizeData.size) {
		sizeData.size = 0;
	}
}

var sizeArray = new Array("12px", "14px", "18px", "24px");

function setFontSize(state) {
	if (state == "plus") {
		if (sizeData.size < sizeArray.length) {
			sizeData.size++;
		}
	} else if (state == "minus") {
		if (sizeData.size > 0) {
			sizeData.size--;
		}
	}
	
	// クロスブラウザ導入予定
	document.getElementById("Body").style.fontSize = sizeArray[sizeData.size];
	
	// ボタンの状態を変更
	setButton();
	
	sizeData.store();
}

function setButton() {
	
	if (sizeData.size < sizeArray.length - 1) {
		document.getElementById("fontsize").getElementsByTagName("div")[0].getElementsByTagName("a")[0].style.display = "block";
		document.getElementById("fontsize").getElementsByTagName("div")[0].style.backgroundPosition = "left -63px";
		
	} else {
		document.getElementById("fontsize").getElementsByTagName("div")[0].getElementsByTagName("a")[0].style.display = "none";
		document.getElementById("fontsize").getElementsByTagName("div")[0].style.backgroundPosition = "left -42px";
	}
	
	if (sizeData.size > 0) {
		document.getElementById("fontsize").getElementsByTagName("div")[2].getElementsByTagName("a")[0].style.display = "block";
		document.getElementById("fontsize").getElementsByTagName("div")[2].style.backgroundPosition = "left -63px";
		
	} else {
		document.getElementById("fontsize").getElementsByTagName("div")[2].getElementsByTagName("a")[0].style.display = "none";
		document.getElementById("fontsize").getElementsByTagName("div")[2].style.backgroundPosition = "left -42px";
	}
	
	var height = sizeData.size * 21;
	document.getElementById("fontsize").getElementsByTagName("div")[1].style.backgroundPosition = "left -" + height + "px";
}