if (typeof susan == 'undefined') susan = {};

susan.overlayCanvas = function(canvasId, points, parentId, parentKey) {
	if ($('strokes').value != '' && !window.confirm('Is it ok to modify the current sketch?')) return;
	$('strokes').value += '|' + points;
	susan.drawCanvas(canvasId, points);
}
susan.copyToCanvas = function(canvasId, points, parentId, parentKey) {
	if ($('strokes').value != '' && !window.confirm('Is it ok to delete the current sketch?')) return;
	$('strokes').value = points;
	$(parentId + '-strokes').value = points;
	$(parentId + '-key').value = parentKey;
	susan.initializeCanvas(canvasId, points);
}
susan.checkSave = function() {
	if ($('strokes').value == $('parent-strokes').value) {
		alert('You are not allowed to save another sketch as it is.');
		return false;
	}
	else {
		return true;
	}
}