/* Lowe's offline clone — progressive enhancement only.
 *
 * Every control this file touches already works without JavaScript: the search
 * box is a GET form, the account drawer has a same-origin page fallback, the
 * quantity stepper wraps a number input inside a POST form, and each filter is
 * a checkbox inside the results form with its own submit button. Nothing here
 * contacts a remote origin; the only network call is the same-origin
 * autocomplete endpoint.
 */
(function () {
  "use strict";

  function ready(fn) {
    if (document.readyState !== "loading") {
      fn();
    } else {
      document.addEventListener("DOMContentLoaded", fn);
    }
  }

  /* ----------------------------------------------------------------- */
  /* account drawer                                                     */
  /* ----------------------------------------------------------------- */

  function setupDrawer() {
    var drawer = document.querySelector("[data-account-drawer]");
    var overlay = document.querySelector("[data-account-overlay]");
    if (!drawer || !overlay) {
      return;
    }
    var lastFocus = null;

    function open() {
      lastFocus = document.activeElement;
      drawer.hidden = false;
      overlay.hidden = false;
      document.body.style.overflow = "hidden";
      var focusable = drawer.querySelector(
        "input, button, select, textarea, a[href]"
      );
      if (focusable) {
        focusable.focus();
      }
    }

    function close() {
      drawer.hidden = true;
      overlay.hidden = true;
      document.body.style.overflow = "";
      if (lastFocus && typeof lastFocus.focus === "function") {
        lastFocus.focus();
      }
    }

    document.querySelectorAll("[data-account-open]").forEach(function (trigger) {
      trigger.addEventListener("click", function (event) {
        event.preventDefault();
        open();
      });
    });
    document.querySelectorAll("[data-account-close]").forEach(function (trigger) {
      trigger.addEventListener("click", function (event) {
        event.preventDefault();
        close();
      });
    });
    overlay.addEventListener("click", close);
    document.addEventListener("keydown", function (event) {
      if (event.key === "Escape" && !drawer.hidden) {
        close();
      }
    });
    if (drawer.getAttribute("data-account-drawer") === "open") {
      open();
    }
  }

  /* ----------------------------------------------------------------- */
  /* primary category flyouts                                          */
  /* ----------------------------------------------------------------- */

  function setupCatnav() {
    var menus = Array.prototype.slice.call(
      document.querySelectorAll("[data-catnav-menu]")
    );
    if (!menus.length) {
      return;
    }

    function closeOthers(active) {
      menus.forEach(function (menu) {
        if (menu !== active) {
          menu.open = false;
        }
      });
    }

    menus.forEach(function (menu) {
      var item = menu.closest(".catnav__item") || menu;
      var summary = menu.querySelector("summary");
      var openedByHover = false;
      var pinnedByClick = false;
      item.addEventListener("mouseenter", function () {
        closeOthers(menu);
        if (!menu.open) {
          menu.open = true;
          openedByHover = true;
        }
      });
      item.addEventListener("mouseleave", function () {
        if (!pinnedByClick) {
          menu.open = false;
        }
        openedByHover = false;
      });
      if (summary) {
        summary.addEventListener("click", function (event) {
          // Pointer entry can open the flyout before the native <details>
          // toggle runs. Own the click transition so pointer and keyboard
          // activation cannot immediately reverse the hover-open state.
          event.preventDefault();
          var shouldOpen = openedByHover || !menu.open;
          closeOthers(menu);
          menu.open = shouldOpen;
          pinnedByClick = shouldOpen;
          openedByHover = false;
        });
      }
      menu.addEventListener("toggle", function () {
        if (menu.open) {
          closeOthers(menu);
        } else {
          pinnedByClick = false;
        }
      });
    });

    document.addEventListener("keydown", function (event) {
      if (event.key === "Escape") {
        closeOthers(null);
      }
    });
  }

  /* ----------------------------------------------------------------- */
  /* search autocomplete                                                */
  /* ----------------------------------------------------------------- */

  function escapeHtml(value) {
    return String(value).replace(/[&<>"']/g, function (character) {
      return {
        "&": "&amp;",
        "<": "&lt;",
        ">": "&gt;",
        '"': "&quot;",
        "'": "&#39;"
      }[character];
    });
  }

  function highlight(label, query) {
    var safe = escapeHtml(label);
    var needle = query.trim();
    if (!needle) {
      return safe;
    }
    var index = safe.toLowerCase().indexOf(escapeHtml(needle).toLowerCase());
    if (index < 0) {
      return safe;
    }
    var end = index + needle.length;
    return (
      safe.slice(0, index) +
      "<mark>" +
      safe.slice(index, end) +
      "</mark>" +
      safe.slice(end)
    );
  }

  function setupSuggest() {
    var form = document.querySelector("[data-suggest-form]");
    if (!form) {
      return;
    }
    var input = form.querySelector("[data-suggest-input]");
    var panel = document.querySelector("[data-suggest-panel]");
    if (!input || !panel) {
      return;
    }
    var items = [];
    var cursor = -1;
    var timer = null;

    function hide() {
      panel.hidden = true;
      panel.innerHTML = "";
      items = [];
      cursor = -1;
      input.setAttribute("aria-expanded", "false");
    }

    function render(payload) {
      var groups = payload && payload.groups ? payload.groups : [];
      var html = "";
      items = [];
      groups.forEach(function (group) {
        if (!group.items || !group.items.length) {
          return;
        }
        html += '<div class="suggestions__group">';
        html += '<div class="suggestions__label">' + escapeHtml(group.label) + "</div>";
        group.items.forEach(function (item) {
          var index = items.length;
          items.push(item);
          html +=
            '<button type="button" class="suggestions__item" role="option"' +
            ' aria-selected="false" data-suggest-index="' +
            index +
            '">' +
            highlight(item.label, input.value) +
            "</button>";
        });
        html += "</div>";
      });
      if (!items.length) {
        hide();
        return;
      }
      panel.innerHTML = html;
      panel.hidden = false;
      input.setAttribute("aria-expanded", "true");
      cursor = -1;
    }

    function move(delta) {
      if (!items.length) {
        return;
      }
      var buttons = panel.querySelectorAll("[data-suggest-index]");
      if (cursor >= 0 && buttons[cursor]) {
        buttons[cursor].setAttribute("aria-selected", "false");
      }
      cursor = (cursor + delta + items.length) % items.length;
      if (buttons[cursor]) {
        buttons[cursor].setAttribute("aria-selected", "true");
        buttons[cursor].scrollIntoView({ block: "nearest" });
      }
    }

    function choose(index) {
      var item = items[index];
      if (!item) {
        return;
      }
      if (item.href) {
        window.location.assign(item.href);
        return;
      }
      input.value = item.label;
      form.submit();
    }

    function request() {
      var query = input.value.trim();
      if (query.length < 2) {
        hide();
        return;
      }
      fetch("/api/suggest?q=" + encodeURIComponent(query), {
        headers: { Accept: "application/json" },
        credentials: "same-origin"
      })
        .then(function (response) {
          return response.ok ? response.json() : { groups: [] };
        })
        .then(render)
        .catch(hide);
    }

    input.addEventListener("input", function () {
      window.clearTimeout(timer);
      timer = window.setTimeout(request, 90);
    });
    input.addEventListener("keydown", function (event) {
      if (panel.hidden) {
        return;
      }
      if (event.key === "ArrowDown") {
        event.preventDefault();
        move(1);
      } else if (event.key === "ArrowUp") {
        event.preventDefault();
        move(-1);
      } else if (event.key === "Enter" && cursor >= 0) {
        event.preventDefault();
        choose(cursor);
      } else if (event.key === "Escape") {
        hide();
      }
    });
    panel.addEventListener("click", function (event) {
      var target = event.target.closest("[data-suggest-index]");
      if (target) {
        choose(Number(target.getAttribute("data-suggest-index")));
      }
    });
    document.addEventListener("click", function (event) {
      if (!form.contains(event.target) && !panel.contains(event.target)) {
        hide();
      }
    });
  }

  /* ----------------------------------------------------------------- */
  /* quantity steppers + auto-submitting selects                        */
  /* ----------------------------------------------------------------- */

  function setupSteppers() {
    document.querySelectorAll("[data-quantity]").forEach(function (widget) {
      var input = widget.querySelector("input[type=number]");
      if (!input) {
        return;
      }
      widget.querySelectorAll("[data-quantity-step]").forEach(function (button) {
        button.addEventListener("click", function () {
          var step = Number(button.getAttribute("data-quantity-step"));
          var min = Number(input.getAttribute("min") || 1);
          var max = Number(input.getAttribute("max") || 99);
          var next = Math.min(max, Math.max(min, Number(input.value || min) + step));
          input.value = String(next);
          input.dispatchEvent(new Event("change", { bubbles: true }));
        });
      });
    });
  }

  function setupAutoSubmit() {
    document.querySelectorAll("[data-autosubmit]").forEach(function (control) {
      control.addEventListener("change", function () {
        var form = control.form;
        if (form) {
          form.requestSubmit ? form.requestSubmit() : form.submit();
        }
      });
    });
  }

  /* ----------------------------------------------------------------- */
  /* product gallery                                                    */
  /* ----------------------------------------------------------------- */

  function setupGallery() {
    var stage = document.querySelector("[data-gallery-stage]");
    if (!stage) {
      return;
    }
    document.querySelectorAll("[data-gallery-thumb]").forEach(function (thumb) {
      thumb.addEventListener("click", function () {
        document.querySelectorAll("[data-gallery-thumb]").forEach(function (other) {
          other.setAttribute("aria-current", "false");
        });
        thumb.setAttribute("aria-current", "true");
        stage.setAttribute("src", thumb.getAttribute("data-gallery-thumb"));
        stage.setAttribute("alt", thumb.getAttribute("data-gallery-alt") || "");
      });
    });
  }

  ready(function () {
    setupDrawer();
    setupCatnav();
    setupSuggest();
    setupSteppers();
    setupAutoSubmit();
    setupGallery();
  });
})();