// Chops off the last string segment designated by delimiter. If no delimiter is found then the original string is
// returned instead. The following attributes are accepted:
// string = Required. The string to chop.
// delimiter = Optional. The delimiter used to chop up the string. Defaults to '_'.
function stringChop(string, delimiter) {
	var chopped = string;
	if (delimiter == undefined) {delimiter = '_';}
	var endIndex = string.lastIndexOf(delimiter);
	if (endIndex > 1) {chopped = string.slice(0, endIndex);}
	return chopped;
};

// Increments a number embedded in the text by one. If no number is found then the original text is returned.
function incrementText(text) {
  if (text != undefined) {
	  var match = text.match(/\d+/);
	  if (match != null) {
		var number = new Number(match);
		var newNumber = number + 1;
		text = text.replace(number, newNumber);
	  }
  }
  return text;
};

// Increments the input field ID number by one so ActiveRecord can save new record attributes.
function incrementInputId(input) {
  id = $(input).attr("id");
  id = incrementText(id);
  $(input).attr("id", id);
};

// Increments the input field name number by one so ActiveRecord can save new record attributes.
function incrementInputName(input) {
  name = $(input).attr("name");
  name = incrementText(name);
  $(input).attr("name", name);
};

// Generates a hidden input field based off original input field data that instructs ActiveRecord to delete
// a record based on the ID of the input field.
function generateDestroyInput(input) {
	$(input).attr("id", stringChop($(input).attr("id")) + "__delete");
	$(input).attr("name", stringChop($(input).attr("name"), '[') + "[_delete]");
	$(input).attr("type", "hidden");
	$(input).attr("value", 1);
	return input;
};

// Animates the removal of a DOM element.
function animateDestroy(id) {
	$(id).animate({backgroundColor: "#FF0000", border: "0.2em solid #FF0000"}, 500);
	$(id).fadeOut(500);
};

// UJS
$(document).ready(function(){
	// Nested New
	$("a.new-nested").click(function(){
		var parentId = '#' + stringChop($(this).attr("id"));
		var child = $(parentId).children(":last").clone(true);
		var childId = child.attr("id");
		child.attr("id", incrementText(childId));
		$(parentId).append(child);
		// Ensure the cloned input fields are unique.
		$('#' + child.attr("id") + " :input").each(function(){
		  	incrementInputId(this);
		  	incrementInputName(this);
			$(this).attr("value", '');
			return this;
		});
		// Ensure the cloned destroy link is unique.
		destroyLink = $("a.destroy-nested:last");
		destroyLink.attr("id", incrementText(destroyLink.attr("id")));
		// Ensure that the default event does not fire.
		return false;
	});
	
	// Nested Destroy
    $("a.destroy-nested").click(function(){
		try {
			var id = $(this).attr("id");
			var parentId = stringChop(id);
			if (parentId != id) {
				parentId = '#' + parentId;
				$(parentId).prepend(generateDestroyInput($(parentId + " input:first").clone()));
				animateDestroy(parentId);
			} else {
				throw "Invalid ID";
			}
		} catch (e) {
			alert("Error: " + e + ". Check that parent ID is defined and/or the link ID includes parent ID as part of the link ID.");
		}
		// Ensure that the default event does not fire.
		return false;
    });

	// Destroy
    $("a.destroy").click(function(){
        var result = confirm("Are you sure you want to delete this?");
        if (result) {
			try {
				var id = $(this).attr("id");
				var parentId = stringChop(id);
				if (parentId != id) {
					animateDestroy('#' + parentId);
				} else {
					throw "Invalid ID";
				}
				// Finally, call the destroy action.
	            $.post($(this).attr("href"), "_method=delete");
			} catch (e) {
				alert("Error: " + e + ". Check that parent ID is defined and/or the link ID includes parent ID as part of the link ID.");
			}
        }
		// Ensure that the default event does not fire.
		return false;
    });
});