MediaWiki:DetailToggle.js

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(function($) {
    "use strict";
    $(document).ready(function() {

        if (typeof(Storage) === "undefined") {
            return;
        }
        
        var ToggleStorage = function(property, property_default) {
            if (!localStorage[property]) {
                localStorage[property] = property_default;
            }
            return {
                toggle: function() {
                    localStorage[property] = localStorage[property] === "show" ? "hide" : "show";
                },
                on: function() {
                    return localStorage[property] === "show";
                }
            };
        }

        function update(toggle_element, toggle) {
            var property = toggle_element.data("target") || "default",
                property_default = toggle_element.data("default") || "show",
                target = "toggle-target-" + property,
                target_class = "." + target,
                toggleStorage = ToggleStorage(target, property_default);
            if (toggle) {
                toggleStorage.toggle();
            }
            if (toggleStorage.on()) {
                toggle_element.find(".toggle-show").show();
                toggle_element.find(".toggle-hide").hide();
                $(target_class).show();
            } else {
                toggle_element.find(".toggle-show").hide();
                toggle_element.find(".toggle-hide").show();
                $(target_class).hide();
            }
        }
        
        $(".toggle").each(function() {
            $(this).show();
            update($(this));
        });

        $(".toggle").click(function() {
            update($(this), true);
        });

    });
}(jQuery));