(function ($) {
  /**
   * Generate an indented list of links from a nav. Meant for use with panel().
   * @return {jQuery} jQuery object.
   */
  $.fn.navList = function () {
    var $this = $(this);
    ($a = $this.find("a")), (b = []);

    $a.each(function () {
      var $this = $(this),
        indent = Math.max(0, $this.parents("li").length - 1),
        href = $this.attr("href"),
        target = $this.attr("target");

      b.push(
        "<a " +
          'class="link depth-' +
          indent +
          '"' +
          (typeof target !== "undefined" && target != ""
            ? ' target="' + target + '"'
            : "") +
          (typeof href !== "undefined" && href != ""
            ? ' href="' + href + '"'
            : "") +
          ">" +
          '<span class="indent-' +
          indent +
          '"></span>' +
          $this.text() +
          "</a>",
      );
    });

    return b.join("");
  };

  /**
   * Panel-ify an element.
   * @param {object} userConfig User config.
   * @return {jQuery} jQuery object.
   */
  $.fn.panel = function (userConfig) {
    // No elements?
    if (this.length == 0) return $this;

    // Multiple elements?
    if (this.length > 1) {
      for (var i = 0; i < this.length; i++) $(this[i]).panel(userConfig);

      return $this;
    }

    // Vars.
    var $this = $(this),
      $body = $("body"),
      $window = $(window),
      id = $this.attr("id"),
      config;

    // Config.
    config = $.extend(
      {
        // Delay.
        delay: 0,

        // Hide panel on link click.
        hideOnClick: false,

        // Hide panel on escape keypress.
        hideOnEscape: false,

        // Hide panel on swipe.
        hideOnSwipe: false,

        // Reset scroll position on hide.
        resetScroll: false,

        // Reset forms on hide.
        resetForms: false,

        // Side of viewport the panel will appear.
        side: null,

        // Target element for "class".
        target: $this,

        // Class to toggle.
        visibleClass: "visible",
      },
      userConfig,
    );

    // Expand "target" if it's not a jQuery object already.
    if (typeof config.target != "jQuery") config.target = $(config.target);

    // Panel.

    // Methods.
    $this._hide = function (event) {
      // Already hidden? Bail.
      if (!config.target.hasClass(config.visibleClass)) return;

      // If an event was provided, cancel it.
      if (event) {
        event.preventDefault();
        event.stopPropagation();
      }

      // Hide.
      config.target.removeClass(config.visibleClass);

      // Post-hide stuff.
      window.setTimeout(function () {
        // Reset scroll position.
        if (config.resetScroll) $this.scrollTop(0);

        // Reset forms.
        if (config.resetForms)
          $this.find("form").each(function () {
            this.reset();
          });
      }, config.delay);
    };

    // Vendor fixes.
    $this
      .css("-ms-overflow-style", "-ms-autohiding-scrollbar")
      .css("-webkit-overflow-scrolling", "touch");

    // Hide on click.
    if (config.hideOnClick) {
      $this.find("a").css("-webkit-tap-highlight-color", "rgba(0,0,0,0)");

      $this.on("click", "a", function (event) {
        var $a = $(this),
          href = $a.attr("href"),
          target = $a.attr("target");

        if (!href || href == "#" || href == "" || href == "#" + id) return;

        // Cancel original event.
        event.preventDefault();
        event.stopPropagation();

        // Hide panel.
        $this._hide();

        // Redirect to href.
        window.setTimeout(function () {
          if (target == "_blank") window.open(href);
          else window.location.href = href;
        }, config.delay + 10);
      });
    }

    // Event: Touch stuff.
    $this.on("touchstart", function (event) {
      $this.touchPosX = event.originalEvent.touches[0].pageX;
      $this.touchPosY = event.originalEvent.touches[0].pageY;
    });

    $this.on("touchmove", function (event) {
      if ($this.touchPosX === null || $this.touchPosY === null) return;

      var diffX = $this.touchPosX - event.originalEvent.touches[0].pageX,
        diffY = $this.touchPosY - event.originalEvent.touches[0].pageY,
        th = $this.outerHeight(),
        ts = $this.get(0).scrollHeight - $this.scrollTop();

      // Hide on swipe?
      if (config.hideOnSwipe) {
        var result = false,
          boundary = 20,
          delta = 50;

        switch (config.side) {
          case "left":
            result = diffY < boundary && diffY > -1 * boundary && diffX > delta;
            break;

          case "right":
            result =
              diffY < boundary && diffY > -1 * boundary && diffX < -1 * delta;
            break;

          case "top":
            result = diffX < boundary && diffX > -1 * boundary && diffY > delta;
            break;

          case "bottom":
            result =
              diffX < boundary && diffX > -1 * boundary && diffY < -1 * delta;
            break;

          default:
            break;
        }

        if (result) {
          $this.touchPosX = null;
          $this.touchPosY = null;
          $this._hide();

          return false;
        }
      }

      // Prevent vertical scrolling past the top or bottom.
      if (
        ($this.scrollTop() < 0 && diffY < 0) ||
        (ts > th - 2 && ts < th + 2 && diffY > 0)
      ) {
        event.preventDefault();
        event.stopPropagation();
      }
    });

    // Event: Prevent certain events inside the panel from bubbling.
    $this.on("click touchend touchstart touchmove", function (event) {
      event.stopPropagation();
    });

    // Event: Hide panel if a child anchor tag pointing to its ID is clicked.
    $this.on("click", 'a[href="#' + id + '"]', function (event) {
      event.preventDefault();
      event.stopPropagation();

      config.target.removeClass(config.visibleClass);
    });

    // Body.

    // Event: Hide panel on body click/tap.
    $body.on("click touchend", function (event) {
      $this._hide(event);
    });

    // Event: Toggle.
    $body.on("click", 'a[href="#' + id + '"]', function (event) {
      event.preventDefault();
      event.stopPropagation();

      config.target.toggleClass(config.visibleClass);
    });

    // Window.

    // Event: Hide on ESC.
    if (config.hideOnEscape)
      $window.on("keydown", function (event) {
        if (event.keyCode == 27) $this._hide(event);
      });

    return $this;
  };

  /**
   * Apply "placeholder" attribute polyfill to one or more forms.
   * @return {jQuery} jQuery object.
   */
  $.fn.placeholder = function () {
    // Browser natively supports placeholders? Bail.
    if (typeof document.createElement("input").placeholder != "undefined")
      return $(this);

    // No elements?
    if (this.length == 0) return $this;

    // Multiple elements?
    if (this.length > 1) {
      for (var i = 0; i < this.length; i++) $(this[i]).placeholder();

      return $this;
    }

    // Vars.
    var $this = $(this);

    // Text, TextArea.
    $this
      .find("input[type=text],textarea")
      .each(function () {
        var i = $(this);

        if (i.val() == "" || i.val() == i.attr("placeholder"))
          i.addClass("polyfill-placeholder").val(i.attr("placeholder"));
      })
      .on("blur", function () {
        var i = $(this);

        if (i.attr("name").match(/-polyfill-field$/)) return;

        if (i.val() == "")
          i.addClass("polyfill-placeholder").val(i.attr("placeholder"));
      })
      .on("focus", function () {
        var i = $(this);

        if (i.attr("name").match(/-polyfill-field$/)) return;

        if (i.val() == i.attr("placeholder"))
          i.removeClass("polyfill-placeholder").val("");
      });

    // Password.
    $this.find("input[type=password]").each(function () {
      var i = $(this);
      var x = $(
        $("<div>")
          .append(i.clone())
          .remove()
          .html()
          .replace(/type="password"/i, 'type="text"')
          .replace(/type=password/i, "type=text"),
      );

      if (i.attr("id") != "") x.attr("id", i.attr("id") + "-polyfill-field");

      if (i.attr("name") != "")
        x.attr("name", i.attr("name") + "-polyfill-field");

      x.addClass("polyfill-placeholder")
        .val(x.attr("placeholder"))
        .insertAfter(i);

      if (i.val() == "") i.hide();
      else x.hide();

      i.on("blur", function (event) {
        event.preventDefault();

        var x = i
          .parent()
          .find("input[name=" + i.attr("name") + "-polyfill-field]");

        if (i.val() == "") {
          i.hide();
          x.show();
        }
      });

      x.on("focus", function (event) {
        event.preventDefault();

        var i = x
          .parent()
          .find(
            "input[name=" + x.attr("name").replace("-polyfill-field", "") + "]",
          );

        x.hide();

        i.show().focus();
      }).on("keypress", function (event) {
        event.preventDefault();
        x.val("");
      });
    });

    // Events.
    $this
      .on("submit", function () {
        $this
          .find("input[type=text],input[type=password],textarea")
          .each(function (event) {
            var i = $(this);

            if (i.attr("name").match(/-polyfill-field$/)) i.attr("name", "");

            if (i.val() == i.attr("placeholder")) {
              i.removeClass("polyfill-placeholder");
              i.val("");
            }
          });
      })
      .on("reset", function (event) {
        event.preventDefault();

        $this.find("select").val($("option:first").val());

        $this.find("input,textarea").each(function () {
          var i = $(this),
            x;

          i.removeClass("polyfill-placeholder");

          switch (this.type) {
            case "submit":
            case "reset":
              break;

            case "password":
              i.val(i.attr("defaultValue"));

              x = i
                .parent()
                .find("input[name=" + i.attr("name") + "-polyfill-field]");

              if (i.val() == "") {
                i.hide();
                x.show();
              } else {
                i.show();
                x.hide();
              }

              break;

            case "checkbox":
            case "radio":
              i.attr("checked", i.attr("defaultValue"));
              break;

            case "text":
            case "textarea":
              i.val(i.attr("defaultValue"));

              if (i.val() == "") {
                i.addClass("polyfill-placeholder");
                i.val(i.attr("placeholder"));
              }

              break;

            default:
              i.val(i.attr("defaultValue"));
              break;
          }
        });
      });

    return $this;
  };

  /**
   * Moves elements to/from the first positions of their respective parents.
   * @param {jQuery} $elements Elements (or selector) to move.
   * @param {bool} condition If true, moves elements to the top. Otherwise, moves elements back to their original locations.
   */
  $.prioritize = function ($elements, condition) {
    var key = "__prioritize";

    // Expand $elements if it's not already a jQuery object.
    if (typeof $elements != "jQuery") $elements = $($elements);

    // Step through elements.
    $elements.each(function () {
      var $e = $(this),
        $p,
        $parent = $e.parent();

      // No parent? Bail.
      if ($parent.length == 0) return;

      // Not moved? Move it.
      if (!$e.data(key)) {
        // Condition is false? Bail.
        if (!condition) return;

        // Get placeholder (which will serve as our point of reference for when this element needs to move back).
        $p = $e.prev();

        // Couldn't find anything? Means this element's already at the top, so bail.
        if ($p.length == 0) return;

        // Move element to top of parent.
        $e.prependTo($parent);

        // Mark element as moved.
        $e.data(key, $p);
      }

      // Moved already?
      else {
        // Condition is true? Bail.
        if (condition) return;

        $p = $e.data(key);

        // Move element back to its original location (using our placeholder).
        $e.insertAfter($p);

        // Unmark element as moved.
        $e.removeData(key);
      }
    });
  };
})(jQuery);