body = document.getElementsByTagName('body')[0];

if (navigator.userAgent.indexOf('Mac') >= 0 && navigator.appName.charAt(0) == "M") {
	false;
} else {
	document.write('<p id="previewTitle">Preview Area</p><p id="preview">ここでコメントが確認できます。</p><p class="postedalone">from <span id="previewName" class="poster">No Name</span><span id="authorURL"></span></p>');
}

if (navigator.userAgent.indexOf('Mac') >= 0 && navigator.appName.charAt(0) == "M") {
	false;
} else {
	if(body.getAttribute("style") == body.style) {
		document.getElementById('author').setAttribute('onkeyup',new Function('namePrev();'));
		document.getElementById('url').setAttribute('onkeyup',new Function('URLPrev();'));
		document.getElementById('text').setAttribute('onkeyup',new Function('commentPrev();'));
		document.getElementById('text').setAttribute('onblur',new Function('commentPrev();'));
		document.getElementById('text').setAttribute('onfocus',new Function('clearText();'));
	} else {
		document.getElementById('author').setAttribute('onkeyup','namePrev();');
		document.getElementById('url').setAttribute('onkeyup','URLPrev();');
		document.getElementById('text').setAttribute('onkeyup','commentPrev();');
		document.getElementById('text').setAttribute('onblur','commentPrev();');
		document.getElementById('text').setAttribute('onfocus','clearText();');
	
	}
}


function commentPrev(){
	Comment = document.getElementById('text').value;
	for(i = 0; i < Comment.length; i++){
		Comment = Comment.replace('\n', '<br />');
	}
	document.getElementById('preview').innerHTML = Comment;
	
	if (document.getElementById('author').value != '') {
			document.getElementById('previewName').innerHTML = document.getElementById('author').value;
	}
	if(Comment == ''){
		document.getElementById('preview').innerHTML = '&nbsp;';
	}
}

function namePrev(){
	Name = document.getElementById('author').value;
	if(Name == ''){
		Name = 'No Name'
	}
	document.getElementById('previewName').innerHTML = Name;
}

function URLPrev(){
	textURL = document.getElementById('url').value;
	if(textURL == ''){
		document.getElementById('authorURL').innerHTML = '';
	} else {
		document.getElementById('authorURL').innerHTML = ' &lt;' + textURL + '&gt;';
	}
}

function clearText(){
	if(document.getElementById('text').value == 'Comment! Comment!'){
		document.getElementById('text').value='';
		document.getElementById('preview').innerHTML = '&nbsp;';
	}
}