import { apiClient, ApiError } from '/static/portal/common/api-client.js?v=20260913';
import { getAccessToken, getAuthContext } from '/static/portal/common/auth.js?v=20260913';
import { escapeHtml } from '/static/portal/common/formatters.js';
import { saveVisitorToken, visitorToken, visitorTokenExpired } from '/static/portal/common/visitor-token.js';

function mountMarkup(mode) {
  const isCustomer = mode === 'customer';
  document.body.insertAdjacentHTML('beforeend', `
    <aside class="cs-widget" data-cs-widget data-mode="${isCustomer ? 'customer' : 'visitor'}">
      <button class="cs-widget__launcher" type="button" aria-label="打开智能客服" aria-expanded="false" data-cs-launcher>
        <span class="cs-widget__orb" aria-hidden="true"><span></span></span>
        <span class="cs-widget__launcher-copy"><strong>南方小助</strong><small>${isCustomer ? '专属服务' : '基金问答'}</small></span>
      </button>
      <section class="cs-widget__panel" aria-label="智能客服对话" hidden data-cs-panel>
        <header class="cs-widget__header"><div><p class="cs-widget__eyebrow">${isCustomer ? '已登录客户' : '公开服务'}</p><h2>智能客服</h2></div><button class="cs-widget__close" type="button" aria-label="关闭客服" data-cs-close>×</button></header>
        <div class="cs-widget__notice">${isCustomer ? '可查询您的测评、账户与基金服务信息。' : '可查询公开基金与服务规则，账户问题请先登录。'}</div>
        <div class="cs-widget__messages" role="log" aria-live="polite" data-cs-messages><div class="cs-widget__message cs-widget__message--assistant">您好，我是南方小助。${isCustomer ? '可以帮您查询账户相关服务。' : '可以帮您了解公开基金与服务规则。'}</div></div>
        <form class="cs-widget__composer" data-cs-form><input name="message" maxlength="8000" autocomplete="off" placeholder="请输入您的问题" aria-label="输入问题" required><button type="submit" aria-label="发送问题">发送</button></form>
        <div class="cs-widget__footer"><button type="button" data-cs-login>${isCustomer ? '转人工客服' : '登录后查询账户'}</button><span data-cs-status>内容来自已发布知识与权限范围</span></div>
      </section>
    </aside>`);
}

export function mountCustomerServiceWidget(mode = 'public') {
  if (document.querySelector('[data-cs-widget]')) return;
  mountMarkup(mode);
  const root = document.querySelector('[data-cs-widget]');
  const launcher = root.querySelector('[data-cs-launcher]');
  const panel = root.querySelector('[data-cs-panel]');
  const messages = root.querySelector('[data-cs-messages]');
  const form = root.querySelector('[data-cs-form]');
  const input = form.elements.message;
  const status = root.querySelector('[data-cs-status]');
  const isCustomer = mode === 'customer';
  let sessionId = '';
  let busy = false;

  const setOpen = (open) => {
    panel.hidden = !open;
    launcher.setAttribute('aria-expanded', String(open));
    root.classList.toggle('cs-widget--open', open);
    if (open) window.setTimeout(() => input.focus(), 60);
  };
  const addMessage = (text, role = 'assistant') => {
    const item = document.createElement('div');
    item.className = `cs-widget__message cs-widget__message--${role}`;
    item.textContent = text;
    messages.appendChild(item);
    messages.scrollTop = messages.scrollHeight;
    return item;
  };
  const authHeaders = () => {
    const token = getAccessToken();
    return token ? {} : { Authorization: `Bearer ${visitorToken()}` };
  };
  async function ensureVisitorToken() {
    if (isCustomer) return '';
    let token = visitorToken();
    if (!token || visitorTokenExpired(token)) {
      const response = await apiClient.post('V001');
      token = response.data?.access_token || '';
      if (token) saveVisitorToken(token);
    }
    return token;
  }
  async function ensureSession() {
    if (sessionId) return sessionId;
    // Visitor tokens intentionally carry only agent:run + knowledge:query. They
    // use an ephemeral run session, while authenticated customers get a persisted
    // conversation resource with conversation:create permission.
    if (!isCustomer) {
      await ensureVisitorToken();
      sessionId = crypto.randomUUID();
      return sessionId;
    }
    await ensureVisitorToken();
    const response = await apiClient.post('C001', { agent_type: 'customer_service' }, { headers: authHeaders() });
    sessionId = response.data?.session_id || '';
    if (!sessionId) throw new ApiError('客服会话未建立');
    return sessionId;
  }
  async function waitForRun(runId) {
    // 实测（本机 + DeepSeek）：整条链路「受理 0.05s + 意图分类 + 知识检索 + 落库」
    // 约 4.1–4.8 秒。原参数是「350ms 后首次、之后每 700ms 一次、共 14 次」≈ 9.5 秒封顶，
    // 后端稍一抖动就撞上限；而且平均要多等半个轮询周期（350ms）才看到结果。
    // 改为「300ms 后首次、之后每 500ms 一次、共 40 次」≈ 20 秒：感知延迟压到半秒内，
    // 同时给模型/检索抖动留出余量。
    // ⚠️ 若这里仍然超时，先确认 Agent Worker 已启动（`python -m app.worker`）——
    //    没有 Worker 时 run 会一直停在 queued，任何轮询预算都不够。
    for (let attempt = 0; attempt < 40; attempt += 1) {
      await new Promise((resolve) => window.setTimeout(resolve, attempt ? 500 : 300));
      const response = await apiClient.get('R002', { pathParams: { runId }, headers: authHeaders() });
      const snapshot = response.data || {};
      if (snapshot.status === 'succeeded') return snapshot.result?.reply || snapshot.result?.content || '暂时没有可展示的回复。';
      if (snapshot.status === 'failed' || snapshot.status === 'cancelled') throw new ApiError('客服暂时无法完成回答，请稍后重试。');
    }
    throw new ApiError('客服繁忙，暂时没能给出答复，请稍后重试。');
  }
  form.addEventListener('submit', async (event) => {
    event.preventDefault();
    const message = String(input.value || '').trim();
    if (!message || busy) return;
    busy = true; input.value = ''; input.disabled = true;
    addMessage(message, 'user');
    const pending = addMessage('正在查询已发布资料…', 'assistant');
    status.textContent = '正在安全处理';
    try {
      const currentSession = await ensureSession();
      const accepted = await apiClient.post('R001', {
        agent_type: 'customer_service', session_id: currentSession, message,
        idempotency_key: crypto.randomUUID().replaceAll('-', ''),
      }, { headers: authHeaders() });
      pending.textContent = await waitForRun(accepted.data?.run_id);
      status.textContent = '已完成回答';
    } catch (error) {
      pending.remove();
      if (error.status === 401 || error.code === 'AUTHENTICATION_REQUIRED') {
        addMessage(isCustomer ? '登录状态已过期，请重新登录后继续。' : '访客服务已过期，请刷新页面后重试。');
      } else if (error.code === 'AGENT_PERMISSION_DENIED') {
        addMessage('当前问题超出该入口的服务范围，建议转人工客服。');
      } else {
        addMessage(error.message || '请求未完成，请稍后重试。');
      }
      status.textContent = '请求未完成';
      apiClient.reportError(error);
    } finally { busy = false; input.disabled = false; input.focus(); }
  });
  launcher.addEventListener('click', () => setOpen(panel.hidden));
  root.querySelector('[data-cs-close]').addEventListener('click', () => setOpen(false));
  root.querySelector('[data-cs-login]').addEventListener('click', async () => {
    if (!isCustomer) { window.location.assign(`/portal/customer/login/?next=${encodeURIComponent(window.location.pathname)}`); return; }
    if (!sessionId) { addMessage('您可以直接输入问题，我会先查询已发布资料。'); input.focus(); return; }
    try {
      const response = await apiClient.post('C005', { reason_code: 'user_requested', reason_detail: '客户通过智能客服浮窗申请人工协助' }, { pathParams: { sessionId } });
      addMessage(`已记录转人工请求（${response.data?.handover_id || '处理中'}），请稍候由客服人员接入。`);
    } catch (error) {
      addMessage(error.message || '转人工请求未完成，请稍后重试。');
      apiClient.reportError(error);
    }
  });
  // Keep the widget identity aligned with an account switch without exposing account data.
  window.addEventListener('portal:auth-changed', () => {
    const context = getAuthContext();
    if (!context && isCustomer) window.location.reload();
  });
}