// MNote UI 基础运行时：全局 portal、toast、居中 confirm/alert。
(function initMnoteUiRuntime() {
  if (window.__mnoteUiRuntimeStarted) return;
  window.__mnoteUiRuntimeStarted = true;

  var nativeConfirm = typeof window.confirm === 'function' ? window.confirm.bind(window) : null;
  var nativeAlert = typeof window.alert === 'function' ? window.alert.bind(window) : null;
  var activeDialog = null;

  function ensurePortalRoot() {
    var root = document.getElementById('mnote-portal-root');
    if (root instanceof HTMLElement) return root;
    root = document.createElement('div');
    root.id = 'mnote-portal-root';
    root.setAttribute('data-mnote-portal-root', 'true');
    document.body.appendChild(root);
    return root;
  }

  function ensureToastRegion() {
    var root = ensurePortalRoot();
    var region = root.querySelector('[data-mnote-toast-region="true"]');
    if (region instanceof HTMLElement) return region;
    region = document.createElement('div');
    region.className = 'mnote-toast-region';
    region.setAttribute('data-mnote-toast-region', 'true');
    region.setAttribute('role', 'status');
    region.setAttribute('aria-live', 'polite');
    root.appendChild(region);
    return region;
  }

  function toast(message, options) {
    var text = String(message || '').trim();
    if (!text) return null;
    var config = options || {};
    var kind = String(config.kind || config.type || 'info').trim() || 'info';
    var timeoutMs = Number(config.timeoutMs || config.duration || 3200);
    if (!Number.isFinite(timeoutMs) || timeoutMs < 800) timeoutMs = 3200;
    var region = ensureToastRegion();
    var item = document.createElement('div');
    item.className = 'mnote-toast mnote-toast--' + kind;
    item.setAttribute('data-mnote-toast', 'true');
    item.setAttribute('data-kind', kind);
    item.textContent = text;
    region.appendChild(item);
    requestAnimationFrame(function showToast() {
      item.classList.add('mnote-toast--visible');
    });
    window.setTimeout(function hideToast() {
      item.classList.remove('mnote-toast--visible');
      window.setTimeout(function removeToast() {
        if (item.parentNode) item.parentNode.removeChild(item);
      }, 180);
    }, timeoutMs);
    return item;
  }

  function closeActiveDialog(result) {
    if (!activeDialog) return;
    var state = activeDialog;
    activeDialog = null;
    document.removeEventListener('keydown', state.onKeyDown, true);
    if (state.backdrop && state.backdrop.parentNode) {
      state.backdrop.parentNode.removeChild(state.backdrop);
    }
    if (typeof state.resolve === 'function') state.resolve(result);
  }

  /**
   * 居中对话框。
   * @param {object} options
   * @param {string} [options.title]
   * @param {string} options.message
   * @param {'confirm'|'alert'} [options.mode]
   * @param {string} [options.confirmLabel]
   * @param {string} [options.cancelLabel]
   * @param {'primary'|'danger'} [options.tone]
   * @returns {Promise<boolean>} confirm 模式：确定=true；alert 模式始终 true
   */
  function showDialog(options) {
    var config = options || {};
    var message = String(config.message || '').trim();
    if (!message) return Promise.resolve(config.mode === 'alert');

    return new Promise(function (resolve) {
      if (activeDialog) closeActiveDialog(false);

      var mode = config.mode === 'alert' ? 'alert' : 'confirm';
      var tone = String(config.tone || 'primary');
      var title =
        String(config.title || (mode === 'alert' ? '提示' : '确认')).trim() ||
        (mode === 'alert' ? '提示' : '确认');
      var confirmLabel = String(config.confirmLabel || (mode === 'alert' ? '知道了' : '确定')).trim();
      var cancelLabel = String(config.cancelLabel || '取消').trim();

      var backdrop = document.createElement('div');
      backdrop.className = 'mnote-dialog-backdrop';
      backdrop.setAttribute('data-mnote-dialog-backdrop', 'true');
      backdrop.setAttribute('data-mode', mode);

      var dialog = document.createElement('div');
      dialog.className =
        'mnote-dialog' + (tone === 'danger' ? ' mnote-dialog--danger' : '');
      dialog.setAttribute('role', 'dialog');
      dialog.setAttribute('aria-modal', 'true');
      dialog.setAttribute('data-mnote-dialog', 'true');

      var body = document.createElement('div');
      body.className = 'mnote-dialog__body';

      var titleEl = document.createElement('h2');
      titleEl.className = 'mnote-dialog__title';
      titleEl.textContent = title;
      body.appendChild(titleEl);

      var messageEl = document.createElement('p');
      messageEl.className = 'mnote-dialog__message';
      messageEl.textContent = message;
      body.appendChild(messageEl);
      dialog.appendChild(body);

      var actions = document.createElement('div');
      actions.className = 'mnote-dialog__actions';

      var confirmBtn = document.createElement('button');
      confirmBtn.type = 'button';
      confirmBtn.className =
        'mnote-dialog__btn ' +
        (tone === 'danger' ? 'mnote-dialog__btn--danger' : 'mnote-dialog__btn--primary');
      confirmBtn.setAttribute('data-role', 'confirm');
      confirmBtn.textContent = confirmLabel || '确定';

      if (mode === 'confirm') {
        var cancelBtn = document.createElement('button');
        cancelBtn.type = 'button';
        cancelBtn.className = 'mnote-dialog__btn';
        cancelBtn.setAttribute('data-role', 'cancel');
        cancelBtn.textContent = cancelLabel || '取消';
        cancelBtn.addEventListener('click', function () {
          closeActiveDialog(false);
        });
        actions.appendChild(cancelBtn);
      }

      confirmBtn.addEventListener('click', function () {
        closeActiveDialog(true);
      });
      actions.appendChild(confirmBtn);
      dialog.appendChild(actions);
      backdrop.appendChild(dialog);

      backdrop.addEventListener('click', function (event) {
        if (event.target === backdrop) {
          closeActiveDialog(mode === 'alert' ? true : false);
        }
      });

      var onKeyDown = function (event) {
        if (event.key === 'Escape') {
          event.preventDefault();
          closeActiveDialog(mode === 'alert' ? true : false);
        } else if (event.key === 'Enter') {
          var tag = (event.target && event.target.tagName) || '';
          if (tag === 'TEXTAREA' || tag === 'BUTTON') return;
          event.preventDefault();
          closeActiveDialog(true);
        }
      };

      activeDialog = {
        backdrop: backdrop,
        resolve: resolve,
        onKeyDown: onKeyDown,
      };
      document.addEventListener('keydown', onKeyDown, true);
      ensurePortalRoot().appendChild(backdrop);
      (mode === 'confirm' ? actions.querySelector('[data-role="cancel"]') || confirmBtn : confirmBtn).focus({
        preventScroll: true,
      });
    });
  }

  function confirmDialog(message, options) {
    var config = options && typeof options === 'object' ? options : {};
    return showDialog({
      mode: 'confirm',
      message: message,
      title: config.title,
      confirmLabel: config.confirmLabel || config.okText,
      cancelLabel: config.cancelLabel || config.cancelText,
      tone: config.tone || (config.danger ? 'danger' : 'primary'),
    });
  }

  function alertDialog(message, options) {
    var config = options && typeof options === 'object' ? options : {};
    return showDialog({
      mode: 'alert',
      message: message,
      title: config.title || '提示',
      confirmLabel: config.confirmLabel || config.okText || '知道了',
      tone: config.tone || (config.kind === 'error' || config.danger ? 'danger' : 'primary'),
    }).then(function () {
      return undefined;
    });
  }

  window.mnote = window.mnote || {};
  window.mnote.ensurePortalRoot = ensurePortalRoot;
  window.mnote.toast = toast;
  window.mnote.confirm = confirmDialog;
  window.mnote.alert = alertDialog;
  window.mnote.dialog = showDialog;

  // 全局替换：统一返回 Promise。调用点需 await（已在各 runtime 迁移）。
  window.alert = function mnoteWindowAlert(message) {
    if (!document.body) {
      if (nativeAlert) nativeAlert(message);
      return Promise.resolve();
    }
    return alertDialog(message);
  };

  window.confirm = function mnoteWindowConfirm(message) {
    if (!document.body) {
      return Promise.resolve(nativeConfirm ? !!nativeConfirm(message) : true);
    }
    return confirmDialog(message);
  };

  window.addEventListener('mnote:toast', function onMnoteToast(event) {
    var detail = event && event.detail ? event.detail : {};
    toast(detail.message, detail);
  });

  window.addEventListener('mnote:confirm', function onMnoteConfirm(event) {
    var detail = event && event.detail ? event.detail : {};
    var message = detail.message || '';
    confirmDialog(message, detail).then(function (ok) {
      if (typeof detail.onResult === 'function') detail.onResult(ok);
    });
  });

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', ensurePortalRoot, { once: true });
  } else {
    ensurePortalRoot();
  }
})();