/* ObsiGate — generic themed context menu for the XLSX grid (#155, #179).
 *
 * Builds a small menu anchored at a screen position. Labels, icons and
 * callbacks come from the caller, so no i18n lives here.
 *
 * #179 — every menu entry carries a representative Lucide icon, the menu
 * closes as soon as the focus leaves it (outside click, focusout, Escape,
 * window blur, scroll, resize) and arrow keys walk through the entries.
 * trackDismissable() exposes the same dismissal contract to the other
 * spreadsheet menus (Structure, Mise en forme, Export), which keep their
 * own markup.
 */
import { safeCreateIcons } from '../utils.js';

let _menu = null;
let _openedAt = 0;
// Only a touch long-press can emit a click right after the menu opened.
let _openedByTouch = false;
let _dismissBound = false;

export function closeContextMenu() {
  // Drop the reference BEFORE touching the DOM: removing a menu that holds
  // the focus fires blur/focusout synchronously, which re-enters this very
  // function — a second remove() on the mid-flight node throws NotFoundError
  // and aborts the caller's click handler before its action runs.
  const menu = _menu;
  _menu = null;
  if (menu) menu.remove();
}

export function isContextMenuOpen() {
  return _menu !== null;
}

function bindDismiss() {
  if (_dismissBound) return;
  _dismissBound = true;
  document.addEventListener("click", (e) => {
    if (!_menu) return;
    // Ignore the very gesture that opened the menu — but only for a touch
    // long-press, which is the one that emits a trailing click. A mouse
    // right-click does not, so a deliberate outside click made right after
    // must close the menu instead of being swallowed.
    if (_openedByTouch && Date.now() - _openedAt < 250) return;
    if (e.target && e.target.closest && e.target.closest(".xlsx-context-menu")) return;
    closeContextMenu();
  });
  document.addEventListener("keydown", (e) => {
    if (e.key === "Escape") closeContextMenu();
  });
  // #179 — never linger once the focus moves outside the menu (toolbar
  // button, editor, another panel…). A null relatedTarget (click on a
  // non-focusable cell) is already covered by the click-outside handler.
  document.addEventListener("focusout", (e) => {
    if (!_menu) return;
    const next = e.relatedTarget;
    if (next && _menu.contains(next)) return;
    closeContextMenu();
  });
  if (typeof window !== "undefined") {
    window.addEventListener("blur", closeContextMenu);
    // A scroll detaches the viewport-anchored menu from its cell — except the
    // tail of the smooth scroll that revealed the right-clicked cell (global
    // `scroll-behavior: smooth` keeps firing after the menu opened).
    window.addEventListener("scroll", () => {
      if (Date.now() - _openedAt > 400) closeContextMenu();
    }, true);
    window.addEventListener("resize", closeContextMenu);
  }
}

/**
 * Walk through a menu's buttons with the keyboard (#179).
 * @param {HTMLElement} menuEl - menu container
 * @param {string} itemSelector - CSS selector of the navigable entries
 */
export function enableArrowNav(menuEl, itemSelector) {
  menuEl.addEventListener("keydown", (e) => {
    const items = [...menuEl.querySelectorAll(itemSelector)].filter((b) => !b.disabled);
    if (!items.length) return;
    const idx = items.indexOf(document.activeElement);
    let next = -1;
    if (e.key === "ArrowDown") next = idx < 0 ? 0 : (idx + 1) % items.length;
    else if (e.key === "ArrowUp") next = idx < 0 ? items.length - 1 : (idx - 1 + items.length) % items.length;
    else if (e.key === "Home") next = 0;
    else if (e.key === "End") next = items.length - 1;
    else return;
    e.preventDefault();
    items[next].focus();
  });
}

/**
 * Dismissal contract shared by the spreadsheet's other menus (#179).
 * Closes on outside click (the toggle button owns its own clicks), Escape,
 * focus leaving both the menu and its toggle, scroll and resize.
 * @param {HTMLElement} menuEl - menu element to watch
 * @param {object} opts
 * @param {HTMLElement|null} opts.toggle - button opening the menu (exempt)
 * @param {Function|null} opts.onClose - called once on dismissal (default: remove the element)
 * @returns {Function} dismiss() — idempotent manual close (unbinds + onClose)
 */
export function trackDismissable(menuEl, { toggle = null, onClose = null } = {}) {
  let done = false;
  const unbind = () => {
    document.removeEventListener("click", onDocClick);
    document.removeEventListener("keydown", onKey);
    document.removeEventListener("focusout", onFocusOut);
    if (typeof window !== "undefined") {
      window.removeEventListener("scroll", onScroll, true);
      window.removeEventListener("resize", onScroll);
    }
  };
  const dismiss = () => {
    if (done) return;
    done = true;
    unbind();
    if (onClose) onClose();
    else menuEl.remove();
  };
  // A re-render can detach the menu without dismissing it: unbind silently
  // instead of leaking listeners on a dead node.
  const dropIfDetached = () => {
    if (!menuEl.isConnected) {
      if (!done) { done = true; unbind(); }
      return true;
    }
    return false;
  };
  const onDocClick = (e) => {
    if (done || dropIfDetached()) return;
    const t = e.target;
    if (menuEl.contains(t)) return;
    if (toggle && (toggle === t || toggle.contains(t))) return;
    dismiss();
  };
  const onKey = (e) => {
    if (dropIfDetached()) return;
    if (e.key === "Escape") dismiss();
  };
  const onFocusOut = (e) => {
    if (done || dropIfDetached()) return;
    const next = e.relatedTarget;
    if (next && (menuEl.contains(next) || (toggle && toggle.contains(next)))) return;
    dismiss();
  };
  // Toolbar-anchored menus travel WITH their button: a scroll inside the
  // hosting toolbar (focus scroll-into-view, horizontal scroll, the menu's
  // own overflow) must not dismiss them — only an outside scroll detaches.
  // Same grace as the grid menu for the smooth-scroll tail of the opening.
  // A body-level menu has no travelling anchor: every scroll detaches it.
  const rawAnchor = (toggle && toggle.closest && toggle.closest(".xlsx-toolbar"))
    || menuEl.parentElement
    || null;
  const anchor = rawAnchor && rawAnchor !== document && rawAnchor !== document.body
    ? rawAnchor
    : null;
  const openedAt = Date.now();
  const onScroll = (e) => {
    if (dropIfDetached()) return;
    if (Date.now() - openedAt < 400) return;
    const t = e && e.target;
    if (t && anchor && (t === anchor || (anchor.contains && anchor.contains(t)))) return;
    dismiss();
  };
  document.addEventListener("click", onDocClick);
  document.addEventListener("keydown", onKey);
  document.addEventListener("focusout", onFocusOut);
  if (typeof window !== "undefined") {
    window.addEventListener("scroll", onScroll, true);
    window.addEventListener("resize", onScroll);
  }
  return dismiss;
}

/**
 * @param {number} x - viewport X of the pointer
 * @param {number} y - viewport Y of the pointer
 * @param {Array<{label?: string, icon?: string, separator?: boolean, danger?: boolean, disabled?: boolean, onClick?: Function}>} items
 * @returns {HTMLElement} the menu element
 */
export function openContextMenu(x, y, items, { byTouch = false } = {}) {
  bindDismiss();
  closeContextMenu();
  const menu = document.createElement("div");
  menu.className = "xlsx-context-menu";
  menu.setAttribute("role", "menu");
  for (const item of items) {
    if (item.separator) {
      const sep = document.createElement("div");
      sep.className = "xlsx-context-sep";
      sep.setAttribute("aria-hidden", "true");
      menu.appendChild(sep);
      continue;
    }
    const btn = document.createElement("button");
    btn.type = "button";
    btn.className = `btn-action xlsx-context-item${item.danger ? " xlsx-context-danger" : ""}`;
    btn.setAttribute("role", "menuitem");
    if (item.icon) {
      const ic = document.createElement("i");
      ic.setAttribute("data-lucide", item.icon);
      ic.className = "xlsx-menu-icon";
      ic.setAttribute("aria-hidden", "true");
      btn.appendChild(ic);
    }
    const lab = document.createElement("span");
    lab.className = "xlsx-menu-label";
    lab.textContent = item.label;
    btn.appendChild(lab);
    btn.disabled = Boolean(item.disabled);
    btn.addEventListener("click", () => {
      closeContextMenu();
      if (!item.disabled && item.onClick) item.onClick();
    });
    menu.appendChild(btn);
  }
  enableArrowNav(menu, ".xlsx-context-item");
  document.body.appendChild(menu);

  // Keep the menu inside the viewport (getBoundingClientRect is 0 in JSDOM,
  // which simply leaves the requested position).
  const rect = menu.getBoundingClientRect();
  const vw = (typeof window !== "undefined" && window.innerWidth) || 1024;
  const vh = (typeof window !== "undefined" && window.innerHeight) || 768;
  const left = Math.max(4, Math.min(x, vw - rect.width - 4));
  const top = Math.max(4, Math.min(y, vh - rect.height - 4));
  menu.style.left = `${left}px`;
  menu.style.top = `${top}px`;

  _menu = menu;
  _openedAt = Date.now();
  _openedByTouch = byTouch;
  // Keyboard users land on the first entry right away; mouse users are
  // unaffected (hover/click still work). preventScroll avoids yanking the grid.
  const first = menu.querySelector(".xlsx-context-item:not(:disabled)");
  if (first && typeof first.focus === "function") {
    try { first.focus({ preventScroll: true }); } catch (_) { first.focus(); }
  }
  if (typeof safeCreateIcons === "function") safeCreateIcons();
  return menu;
}