/** 工单后台：按需加载弹窗，写操作只使用工单 REST 接口。 */
(function () {
  'use strict';

  var root = document.querySelector('.aksrt-tickets-admin');
  var config = window.AKSRTAdminTickets;
  var createDialog = document.getElementById('aksrt-ticket-create-dialog');
  var detailDialog = document.getElementById('aksrt-ticket-detail-dialog');
  if (!root || !config || !createDialog || !detailDialog || typeof detailDialog.showModal !== 'function') return;

  var strings = config.strings;
  var panel = detailDialog.querySelector('[data-aksrt-ticket-panel]');
  var list = root.querySelector('[data-aksrt-ticket-list]');
  var detailTitle = document.getElementById('aksrt-ticket-detail-title');
  var initialTitle = detailTitle.textContent;
  var baselines = new WeakMap();
  var active = null;
  var opener = null;
  var ticketId = 0;
  var saving = false;
  var loading = false;
  var stale = false;
  var retryPage = false;
  var savedMessage = '';
  var savedDrafts = {};
  var disabledControls = [];
  var readController = null;
  var generation = 0;
  var pointerOutside = false;
  var feedbackTimer = 0;

  function values(form) {
    var result = {};
    form.querySelectorAll('input[name], select[name], textarea[name]').forEach(function (field) {
      result[field.name] = field.value;
    });
    return result;
  }

  function drafts(except) {
    var result = {};
    if (!active) return result;
    active.querySelectorAll('[data-aksrt-ticket-form]').forEach(function (form) {
      if (form === except) return;
      var base = baselines.get(form) || {};
      var changed = {};
      var current = values(form);
      Object.keys(current).forEach(function (key) {
        if (current[key] !== base[key]) changed[key] = current[key];
      });
      if (Object.keys(changed).length) result[form.dataset.aksrtTicketForm] = changed;
    });
    return result;
  }

  function dirty() {
    return Object.keys(drafts()).length > 0 || Object.keys(savedDrafts).length > 0;
  }

  function counter(field) {
    var output = root.querySelector('[data-aksrt-ticket-counter="' + field.id + '"]');
    if (!output) return;
    output.textContent = field.value.length + ' / ' + field.maxLength;
    output.classList.toggle('is-over', field.value.length >= field.maxLength);
  }

  function validateText(field) {
    if (field.required && (field.tagName === 'TEXTAREA' || field.type === 'text')) {
      field.setCustomValidity(field.value.trim() ? '' : strings.required);
    }
  }

  function syncStatus(form) {
    var select = form.querySelector('[data-aksrt-ticket-status]');
    if (!select) return;
    var option = select.options[select.selectedIndex];
    var closed = !!option && option.dataset.closed === '1';
    var warning = form.querySelector('[data-aksrt-ticket-close-warning]');
    var confirm = form.querySelector('[data-aksrt-ticket-close-confirm]');
    warning.hidden = !closed;
    confirm.required = closed;
    if (!closed) confirm.checked = false;
  }

  function setupForms(container, restore) {
    container.querySelectorAll('[data-aksrt-ticket-form]').forEach(function (form) {
      baselines.set(form, values(form));
      var changes = (restore || {})[form.dataset.aksrtTicketForm] || {};
      form.querySelectorAll('[name]').forEach(function (field) {
        if (Object.prototype.hasOwnProperty.call(changes, field.name)) field.value = changes[field.name];
        validateText(field);
      });
      syncStatus(form);
    });
    container.querySelectorAll('[data-aksrt-ticket-editor]').forEach(counter);
  }

  /** 成功与可忽略的错误提示自动消失；加载/保存中与需重试的提示保留到状态变化。 */
  function feedback(dialog, message, error, retry) {
    var box = dialog.querySelector('[data-aksrt-ticket-feedback]');
    clearTimeout(feedbackTimer);
    box.hidden = !message;
    box.classList.toggle('is-error', !!error);
    box.querySelector('p').textContent = message || '';
    box.querySelector('[data-aksrt-ticket-retry]').hidden = !retry;
    if (!message || retry || message === strings.loading || message === strings.saving) return;
    feedbackTimer = setTimeout(function () { box.hidden = true; }, error ? 6000 : 3000);
  }

  function busy(value) {
    saving = value;
    if (!active) return;
    active.setAttribute('aria-busy', String(value));
    if (value) {
      disabledControls = [];
      active.querySelectorAll('input, select, textarea, button').forEach(function (control) {
        disabledControls.push([control, control.disabled]);
        control.disabled = true;
      });
    } else {
      disabledControls.forEach(function (entry) { entry[0].disabled = entry[1]; });
      disabledControls = [];
    }
  }

  function lockStaleForms() {
    if (!stale || !active) return;
    active.querySelectorAll('form input, form select, form textarea, form button[type="submit"]').forEach(function (control) {
      control.disabled = true;
    });
    active.querySelectorAll('[data-aksrt-ticket-assign]').forEach(function (button) { button.disabled = true; });
  }

  /** 会话已在底部或无需滚动时隐藏「查看最新记录」，避免点击无反应。 */
  function syncLatest() {
    var conversation = panel.querySelector('.aksrt-ticket-conversation__scroll');
    var button = panel.querySelector('[data-aksrt-ticket-latest]');
    if (!conversation || !button) return;
    button.hidden = conversation.scrollHeight - conversation.clientHeight - conversation.scrollTop <= 8;
  }

  /** 会话内滚到底部；手动触发时同时让弹窗正文露出会话底部。 */
  function showLatest(manual) {
    var conversation = panel.querySelector('.aksrt-ticket-conversation__scroll');
    if (!conversation) return;
    conversation.scrollTop = conversation.scrollHeight;
    if (manual) {
      var gap = conversation.getBoundingClientRect().bottom - panel.getBoundingClientRect().bottom;
      if (gap > 0) panel.scrollTop += gap;
      conversation.focus({ preventScroll: true });
    }
    syncLatest();
  }

  function updateUrl(id, page) {
    var url = new URL(window.location.href);
    if (id) url.searchParams.set('id', String(id));
    else url.searchParams.delete('id');
    if (page) {
      if (page > 1) url.searchParams.set('paged', String(page));
      else url.searchParams.delete('paged');
    }
    url.hash = '';
    window.history.replaceState(window.history.state, '', url.toString());
  }

  async function request(url, options) {
    var response = await fetch(url, Object.assign({ credentials: 'same-origin' }, options));
    var result = await response.json();
    if (!response.ok || !result || result.success !== true) {
      var error = new Error(result && (result.message || (result.data && result.data.message)) || strings.saveFailed);
      error.confirmed = !!result && (result.success === false || typeof result.code === 'string');
      error.status = response.status;
      throw error;
    }
    return result.data;
  }

  function readUrl(id, refresh) {
    var url = new URL(config.ajaxUrl, window.location.href);
    var current = new URL(window.location.href);
    ['status', 'ticket_type_id', 's', 'paged'].forEach(function (key) {
      if (current.searchParams.has(key)) url.searchParams.set(key, current.searchParams.get(key));
    });
    url.searchParams.set('action', 'aksrt_ticket_view');
    url.searchParams.set('nonce', config.readNonce);
    url.searchParams.set('id', String(id));
    if (refresh) url.searchParams.set('refresh_list', '1');
    return url.toString();
  }

  async function loadDetail(id, refresh, message, restore) {
    if (readController) readController.abort();
    var current = ++generation;
    var controller = new AbortController();
    readController = controller;
    var timer = setTimeout(function () { controller.abort(); }, 30000);
    loading = true;
    panel.setAttribute('aria-busy', 'true');
    feedback(detailDialog, strings.loading, false, false);
    try {
      var data = await request(readUrl(id, refresh), { signal: controller.signal, cache: 'no-store' });
      if (current !== generation || active !== detailDialog) return;
      panel.innerHTML = data.panel;
      detailTitle.textContent = data.title;
      if (typeof data.list === 'string') list.innerHTML = data.list;
      updateUrl(id, data.page);
      setupForms(panel, restore);
      showLatest(false);
      var notes = panel.querySelector('.aksrt-ticket-detail__notes');
      if (notes) notes.scrollTop = notes.scrollHeight;
      stale = false;
      savedDrafts = {};
      savedMessage = '';
      feedback(detailDialog, message, false, false);
      if (message) detailTitle.focus();
    } catch (error) {
      if (current !== generation || active !== detailDialog) return;
      stale = true;
      retryPage = [401, 403, 404].indexOf(error.status) !== -1;
      if (error.status === 404) updateUrl(0);
      savedDrafts = restore || {};
      savedMessage = message || '';
      feedback(detailDialog, message ? strings.refreshFailed : (error.confirmed ? error.message : strings.loadFailed), true, true);
    } finally {
      clearTimeout(timer);
      if (current === generation) {
        loading = false;
        panel.removeAttribute('aria-busy');
        readController = null;
        lockStaleForms();
      }
    }
  }

  function show(dialog, source) {
    active = dialog;
    opener = source || null;
    pointerOutside = false;
    stale = false;
    retryPage = false;
    feedback(dialog, '', false, false);
    dialog.showModal();
    document.documentElement.classList.add('aksrt-ticket-modal-open');
  }

  function openDetail(id, source, refresh, message) {
    ticketId = id;
    detailTitle.textContent = initialTitle;
    show(detailDialog, source);
    updateUrl(id);
    return loadDetail(id, !!refresh, message || '', {});
  }

  function close() {
    if (!active || saving) return;
    if (dirty() && !window.confirm(strings.discard)) return;
    active.close();
  }

  root.addEventListener('click', function (event) {
    var create = event.target.closest('[data-aksrt-dialog-open="aksrt-ticket-create-dialog"]');
    var view = event.target.closest('[data-aksrt-ticket-view]');
    if (create || view) {
      event.preventDefault();
      if (active) return;
      if (create) show(createDialog, create);
      else openDetail(parseInt(view.dataset.aksrtTicketView, 10), view);
      return;
    }
    if (!active || saving) return;
    var retry = event.target.closest('[data-aksrt-ticket-retry]');
    if (retry) {
      if (retryPage) { window.location.reload(); return; }
      if (!loading) loadDetail(ticketId, true, savedMessage, Object.assign({}, savedDrafts, drafts()));
      return;
    }
    if (stale || loading) return;
    var assign = event.target.closest('[data-aksrt-ticket-assign]');
    if (assign) {
      var statusForm = assign.closest('section').querySelector('form');
      statusForm.querySelector('[name="admin_id"]').value = String(config.currentUser);
      var statusSelect = statusForm.querySelector('[name="status"]');
      if (statusSelect.value === 'pending') statusSelect.value = 'handling';
      syncStatus(statusForm);
      statusForm.querySelector('[type="submit"]').focus();
    }
    if (event.target.closest('[data-aksrt-ticket-latest]')) showLatest(true);
  });

  root.addEventListener('input', function (event) {
    validateText(event.target);
    if (event.target.matches('[data-aksrt-ticket-editor]')) counter(event.target);
  });

  root.addEventListener('change', function (event) {
    var select = event.target;
    if (select.matches('[data-aksrt-ticket-status]')) {
      select.form.querySelector('[data-aksrt-ticket-close-confirm]').checked = false;
      syncStatus(select.form);
    }
    if (!select.matches('[data-aksrt-ticket-prereply]') || !select.value) return;
    var field = document.getElementById(select.dataset.aksrtTicketPrereply);
    if (!field) return;
    var start = field.selectionStart || 0;
    var end = field.selectionEnd || 0;
    var before = field.value.slice(0, start);
    var insert = (before && !/\n$/.test(before) ? '\n' : '') + select.value;
    var next = before + insert + field.value.slice(end);
    if (next.length > field.maxLength) {
      feedback(active, strings.tooLong, true, false);
    } else {
      field.value = next;
      field.focus();
      field.setSelectionRange(start + insert.length, start + insert.length);
      validateText(field);
      counter(field);
    }
    select.value = '';
  });

  root.addEventListener('submit', async function (event) {
    var form = event.target.closest('[data-aksrt-ticket-form]');
    if (!form) return;
    event.preventDefault();
    if (saving || loading || stale || !active) return;
    form.querySelectorAll('input, textarea').forEach(validateText);
    if (!form.reportValidity()) return;
    var kind = form.dataset.aksrtTicketForm;
    var body = JSON.stringify(values(form));
    var remaining = drafts(form);
    var controller = new AbortController();
    var timer = setTimeout(function () { controller.abort(); }, 30000);
    busy(true);
    feedback(active, strings.saving, false, false);
    try {
      var data = await request(form.action, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json', 'X-WP-Nonce': config.restNonce },
        body: body,
        signal: controller.signal,
      });
      clearTimeout(timer);
      baselines.set(form, values(form));
      if (kind === 'create') {
        var source = opener;
        busy(false);
        await new Promise(function (resolve) {
          createDialog.addEventListener('close', resolve, { once: true });
          createDialog.close();
        });
        await openDetail(data.id, source, true, strings.created);
      } else {
        if (kind !== 'status') form.reset();
        baselines.set(form, values(form));
        await loadDetail(ticketId, true, strings[kind], remaining);
      }
    } catch (error) {
      var reload = !error.confirmed || [401, 403, 404].indexOf(error.status) !== -1;
      stale = reload || error.status === 409;
      retryPage = reload || (kind === 'create' && stale);
      if (error.status === 404) updateUrl(0);
      feedback(active, error.confirmed ? error.message : strings.uncertain, true, stale);
    } finally {
      clearTimeout(timer);
      busy(false);
      lockStaleForms();
    }
  });

  [createDialog, detailDialog].forEach(function (dialog) {
    function outside(event) {
      var rect = dialog.getBoundingClientRect();
      return event.clientX < rect.left || event.clientX > rect.right || event.clientY < rect.top || event.clientY > rect.bottom;
    }
    dialog.addEventListener('pointerdown', function (event) { pointerOutside = event.target === dialog && outside(event); });
    dialog.addEventListener('pointercancel', function () { pointerOutside = false; });
    dialog.addEventListener('click', function (event) {
      if (event.target.closest('[data-aksrt-dialog-close]') || (pointerOutside && event.target === dialog && outside(event))) {
        event.preventDefault();
        close();
      }
      pointerOutside = false;
    });
    dialog.addEventListener('cancel', function (event) { event.preventDefault(); close(); });
    dialog.addEventListener('close', function () {
      var previous = opener;
      var previousId = ticketId;
      if (readController) readController.abort();
      generation += 1;
      readController = null;
      loading = false;
      stale = false;
      savedDrafts = {};
      savedMessage = '';
      if (dialog === detailDialog) {
        panel.replaceChildren();
        updateUrl(0);
      } else {
        var form = dialog.querySelector('form');
        if (form) form.reset();
        setupForms(dialog);
      }
      active = null;
      opener = null;
      ticketId = 0;
      document.documentElement.classList.remove('aksrt-ticket-modal-open');
      if (!previous || !previous.isConnected) previous = root.querySelector('[data-aksrt-ticket-view="' + previousId + '"]') || root.querySelector('[data-aksrt-dialog-open]');
      if (previous) previous.focus();
    });
  });

  // scroll 不冒泡，用捕获监听会话容器。
  panel.addEventListener('scroll', syncLatest, true);
  // 把正文可视高度写给 CSS，用于限制右侧栏高度。
  if (typeof ResizeObserver === 'function') {
    new ResizeObserver(function () {
      panel.style.setProperty('--aksrt-ticket-panel-height', panel.clientHeight + 'px');
    }).observe(panel);
  }

  window.addEventListener('beforeunload', function (event) {
    if (!saving && !dirty()) return;
    event.preventDefault();
    event.returnValue = '';
  });
  setupForms(createDialog);
  var initialId = parseInt(new URL(window.location.href).searchParams.get('id'), 10);
  if (initialId > 0) openDetail(initialId, root.querySelector('[data-aksrt-ticket-view="' + initialId + '"]'));
})();