function image_upload_check() {
	var ext = document.photos_upload.photo.value;
	ext = ext.substring(ext.length-3,ext.length);
	ext = ext.toLowerCase();
	if(ext != 'jpg') {
		alert('You selected a .'+ext+' file; please select a .jpg file instead!');
		return false;
	} else {
		return true; 
	}
} 

function avatar_upload_check() {
	var ext = document.useravatar.avatar.value;
	ext = ext.substring(ext.length-3,ext.length);
	ext = ext.toLowerCase();
	if(ext != 'jpg') {
		alert('You selected a .'+ext+' file; please select a .jpg file instead!');
		return false;
	} else {
		return true;
	}
}

function insert_text_at_cursor(tfield, tstring) {
	if (document.selection) {
		tfield.focus();
		sel = document.selection.createRange();
		sel.text = tstring;
	} else if (tfield.selectionStart || tfield.selectionStart == '0') {
		var startPos = tfield.selectionStart;
		var endPos = tfield.selectionEnd;
		tfield.value = tfield.value.substring(0, startPos)+ tstring+ tfield.value.substring(endPos, tfield.value.length);
	} else {
		tfield.value += tstring;
	}
}

function insert_thumbnail(ifield,istring,iurl) {
	ifield.value=istring;
	opener.document.getElementById('blog_thumbnail').innerHTML = '<img src="'+ iurl+'/' + istring + '">';
}