/**

 * Django admin inlines

 *

 * Based on jQuery Formset 1.1

 * @author Stanislaus Madueke (stan DOT madueke AT gmail DOT com)

 * @requires jQuery 1.2.6 or later

 *

 * Copyright (c) 2009, Stanislaus Madueke

 * All rights reserved.

 *

 * Spiced up with Code from Zain Memon's GSoC project 2009

 * and modified for Django by Jannis Leidel

 *

 * Licensed under the New BSD License

 * See: http://www.opensource.org/licenses/bsd-license.php

 */

(function($) {

	$.fn.formset = function(opts) {

		var options = $.extend({}, $.fn.formset.defaults, opts);

		var updateElementIndex = function(el, prefix, ndx) {

			var id_regex = new RegExp("(" + prefix + "-\\d+)");

			var replacement = prefix + "-" + ndx;

			if ($(el).attr("for")) {

				$(el).attr("for", $(el).attr("for").replace(id_regex, replacement));

			}

			if (el.id) {

				el.id = el.id.replace(id_regex, replacement);

			}

			if (el.name) {

				el.name = el.name.replace(id_regex, replacement);

			}

		};

		var totalForms = $("#id_" + options.prefix + "-TOTAL_FORMS").attr("autocomplete", "off");

		var maxForms = $("#id_" + options.prefix + "-MAX_NUM_FORMS").attr("autocomplete", "off");

		// only show the add button if we are allowed to add more items,

        // note that max_num = None translates to a blank string.

		var showAddButton = maxForms.val() == '' || (maxForms.val()-totalForms.val()) > 0;

		$(this).each(function(i) {

			$(this).not("." + options.emptyCssClass).addClass(options.formCssClass);

		});

		if ($(this).length && showAddButton) {

			var addButton;

			if ($(this).attr("tagName") == "TR") {

				// If forms are laid out as table rows, insert the

				// "add" button in a new table row:

				var numCols = this.eq(0).children().length;

				$(this).parent().append('<tr class="' + options.addCssClass + '"><td colspan="' + numCols + '"><a href="javascript:void(0)">' + options.addText + "</a></tr>");

				addButton = $(this).parent().find("tr:last a");

			} else {

				// Otherwise, insert it immediately after the last form:

				$(this).filter(":last").after('<div class="' + options.addCssClass + '"><a href="javascript:void(0)">' + options.addText + "</a></div>");

				addButton = $(this).filter(":last").next().find("a");

			}

			addButton.click(function() {

				var totalForms = $("#id_" + options.prefix + "-TOTAL_FORMS");

				var nextIndex = parseInt(totalForms.val());

				var template = $("#" + options.prefix + "-empty");

				var row = template.clone(true);

				row.removeClass(options.emptyCssClass)

				    .addClass(options.formCssClass)

				    .attr("id", options.prefix + "-" + nextIndex)

				    .insertBefore($(template));

				row.find("*")

				    .filter(function() {

				        var el = $(this);

				        return el.attr("id") && el.attr("id").search(/__prefix__/) >= 0;

				    }).each(function() {

				        var el = $(this);

				        el.attr("id", el.attr("id").replace(/__prefix__/g, nextIndex));

				    })

				    .end()

				    .filter(function() {

				        var el = $(this);

				        return el.attr("name") && el.attr("name").search(/__prefix__/) >= 0;

				    }).each(function() {

				        var el = $(this);

				        el.attr("name", el.attr("name").replace(/__prefix__/g, nextIndex));

				    });

				if (row.is("tr")) {

					// If the forms are laid out in table rows, insert

					// the remove button into the last table cell:

					row.children(":last").append('<div><a class="' + options.deleteCssClass +'" href="javascript:void(0)">' + options.deleteText + "</a></div>");

				} else if (row.is("ul") || row.is("ol")) {

					// If they're laid out as an ordered/unordered list,

					// insert an <li> after the last list item:

					row.append('<li><a class="' + options.deleteCssClass +'" href="javascript:void(0)">' + options.deleteText + "</a></li>");

				} else {

					// Otherwise, just insert the remove button as the

					// last child element of the form's container:

					row.children(":first").append('<span><a class="' + options.deleteCssClass + '" href="javascript:void(0)">' + options.deleteText + "</a></span>");

				}

				row.find("input,select,textarea,label,a").each(function() {

					updateElementIndex(this, options.prefix, totalForms.val());

				});

				// Update number of total forms

				$(totalForms).val(nextIndex + 1);

				// Hide add button in case we've hit the max, except we want to add infinitely

				if ((maxForms.val() != '') && (maxForms.val() <= totalForms.val())) {

					addButton.parent().hide();

				}

				// The delete button of each row triggers a bunch of other things

				row.find("a." + options.deleteCssClass).click(function() {

					// Remove the parent form containing this button:

					var row = $(this).parents("." + options.formCssClass);

					row.remove();

					// If a post-delete callback was provided, call it with the deleted form:

					if (options.removed) {

						options.removed(row);

					}

					// Update the TOTAL_FORMS form count.

					var forms = $("." + options.formCssClass);

					$("#id_" + options.prefix + "-TOTAL_FORMS").val(forms.length);

					// Show add button again once we drop below max

					if ((maxForms.val() == '') || (maxForms.val() >= forms.length)) {

						addButton.parent().show();

					}

					// Also, update names and ids for all remaining form controls

					// so they remain in sequence:

					for (var i=0, formCount=forms.length; i<formCount; i++)

					{

						$(forms.get(i)).find("input,select,textarea,label,a").each(function() {

							updateElementIndex(this, options.prefix, i);

						});

					}

					return false;

				});

				// If a post-add callback was supplied, call it with the added form:

				if (options.added) {

					options.added(row);

				}

				return false;

			});

		}

		return this;

	}

	/* Setup plugin defaults */

	$.fn.formset.defaults = {

		prefix: "form",					// The form prefix for your django formset

		addText: "add another",			// Text for the add link

		deleteText: "remove",			// Text for the delete link

		addCssClass: "add-row",			// CSS class applied to the add link

		deleteCssClass: "delete-row",	// CSS class applied to the delete link

		emptyCssClass: "empty-row",		// CSS class applied to the empty row

		formCssClass: "dynamic-form",	// CSS class applied to each form in a formset

		added: null,					// Function called each time a new form is added

		removed: null					// Function called each time a form is deleted

	}

})(django.jQuery);