import { useEffect } from 'react';
import { useNavigate, useLocation } from 'react-router-dom';
import { onMqttMessage, connectMqtt, publishMqtt, getClientId, useMqttStatus } from './mqtt';
import { MQTT_TOPIC_HEARTBEAT, MQTT_TOPIC_COMMAND, MQTT_TOPIC_BIND, getApiBase as API_BASE } from '../config';
import { getTenantId, clearBinding } from './tenant';
import { Sfx } from './sounds';
import { PAGE_ORDER } from './pageNav';
import { aiStatus } from './statusBus';
import { invoke } from '@tauri-apps/api/core';
import { getCurrentWindow } from '@tauri-apps/api/window';

// 当前窗口标识：主屏 'main' / 双屏副窗 'secondary'
// 优先用 Rust 注入的 __DPM_WINDOW_LABEL__（副窗初始化脚本），再回退 getCurrentWindow().label
const WINDOW_LABEL = (() => {
  try {
    if (window.__DPM_WINDOW_LABEL__) return window.__DPM_WINDOW_LABEL__;
    return getCurrentWindow().label || 'main';
  } catch { return 'main'; }
})();

/* =========================================================
   MQTT 控制 —— 后端通过 opc/display/command 控制大屏
   · navigate / navigate_rel：页面切换（与方向键同一通道）
   · play / pause / next / prev / set_mode：媒体控制
   · alert：全局通知
   · show_card：展示信息卡片（AI 工具调用 / 管理端指令）
   · 心跳：定时上报 opc/display/heartbeat（后端统计在线大屏）
   ========================================================= */

const PAGE_ALIAS = {
  home: '/', '数据大屏': '/', '首页': '/',
  twin: '/twin', '数字孪生': '/twin', '3d': '/twin',
  ai: '/ai', 'ai助手': '/ai',
  tasks: '/tasks', '任务展示': '/tasks', task: '/tasks',
  screen: '/screen', '媒体轮播': '/screen', media: '/screen',
  wall: '/wall', '企业展示墙': '/wall', '企业墙': '/wall', '展示墙': '/wall',
};

function resolvePage(page) {
  if (!page) return null;
  if (PAGE_ALIAS[String(page).toLowerCase()] !== undefined) return PAGE_ALIAS[String(page).toLowerCase()];
  if (PAGE_ORDER.some((p) => p.path === page)) return page;
  return null;
}

export function useMqttControl() {
  const navigate = useNavigate();
  const location = useLocation();
  const mqttStatus = useMqttStatus();

  // 设备注册：MQTT 连接后向后端上报「唯一 device_id + 角色 + 从属主屏」，供后端精准控制
  useEffect(() => {
    if (mqttStatus !== 'connected' || !getClientId()) return;
    fetch(`${API_BASE()}/api/display/register`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        device_id: getClientId(),
        role: WINDOW_LABEL,
        parent_id: window.__DPM_PARENT_ID__ || '',   // 副屏标识从属的主屏 device_id
      }),
    }).catch(() => {});
  }, [mqttStatus]);

  // 后端主动解绑：监听绑定频道，收到 unbound 事件 → 清理本地绑定并退出到待绑定页
  // （大屏已绑定后仍订阅 bind/<clientId>，见 mqtt.js subscribe；unbind 后 main.jsx 见
  //   isDeviceBound()=false 渲染 BindScreen）
  useEffect(() => {
    connectMqtt();
    const off = onMqttMessage((topic, data) => {
      if (topic === `${MQTT_TOPIC_BIND}/${getClientId()}` && data && data.event === 'unbound') {
        clearBinding();
      }
    });
    return off;
  }, []);

  // 大屏在线心跳（后端据此统计在线大屏数）
  useEffect(() => {
    connectMqtt();
    const sendHeartbeat = () => {
      if (mqttStatus === 'connected') {
        publishMqtt(MQTT_TOPIC_HEARTBEAT, {
          client_id: getClientId(),
          tenant_id: getTenantId(),
          page: location.pathname,
          ts: Date.now(),
        });
      }
    };
    sendHeartbeat();
    const hb = setInterval(sendHeartbeat, 10000);
    return () => clearInterval(hb);
  }, [mqttStatus, location.pathname]);

  // 页面状态即时上报：路由变化即通知服务端当前所在页面
  useEffect(() => {
    connectMqtt();
    if (mqttStatus === 'connected') {
      publishMqtt('opc/frontend/state', {
        client_id: getClientId(),
        page: location.pathname,
        ts: Date.now(),
      });
    }
  }, [mqttStatus, location.pathname]);

  // 控制指令订阅
  useEffect(() => {
    connectMqtt();
    const off = onMqttMessage((topic, cmd) => {
      // 接收全局控制 topic 或本客户端独有 topic（后端按屏幕终端分别下发）
      const isCmd = topic === MQTT_TOPIC_COMMAND || topic.startsWith(`${MQTT_TOPIC_COMMAND}/`);
      if (!isCmd || !cmd || !cmd.action) return;
      // 屏幕终端精准控制：后端按 client_id 路由到独有 topic。
      // 兜底：命令若带 screen_id，只有本客户端 client_id 匹配才处理（防误收全局）。
      const sc = cmd.screen;
      console.warn(`[dual] 命令 action=${cmd.action} screen_id=${cmd.screen_id || '(无)'} screen_role=${cmd.screen_role || '(无)'} 本窗口=${WINDOW_LABEL} 本client=${getClientId()}`);
      if (cmd.screen_id && cmd.screen_id !== getClientId()) return;
      if (sc && sc !== 'both' && sc !== WINDOW_LABEL) return;

      switch (cmd.action) {
        case 'navigate': {
          const path = resolvePage(cmd.params?.page);
          if (path) { Sfx.page(); aiStatus('正在切换页面', { icon: 'page' }); navigate(path); }
          break;
        }
        case 'navigate_rel': {
          const delta = Number(cmd.params?.delta ?? 1) || 1;
          const idx = PAGE_ORDER.findIndex((p) => p.path === location.pathname);
          if (idx >= 0) {
            const n = PAGE_ORDER.length;
            aiStatus('正在切换页面', { icon: 'page' });
            navigate(PAGE_ORDER[(idx + delta + n) % n].path);
          }
          break;
        }
        case 'dual_screen':
          // 双屏：仅主窗口执行（只有主屏能开启/关闭副屏），把主屏 device_id 传给副窗作 parent_id
          if (WINDOW_LABEL !== 'main') break;
          aiStatus(cmd.params?.on === false ? '正在关闭双屏' : '正在启动双屏', { icon: 'page' });
          invoke('set_dual_screen', { on: cmd.params?.on !== false, parentId: getClientId() })
            .catch((err) => {
              const msg = String((err && err.message) || err || '操作失败');
              aiStatus(`双屏失败：${msg}`, { state: 'error', icon: 'error' });
              console.error('[dual]', err);
            });
          break;
        case 'alert':
          // 通知本身即展示，无需再弹「正在发送通知」状态提示
          window.dispatchEvent(new CustomEvent('dpm:alert', { detail: cmd.params || {} }));
          break;
        case 'show_card':
          aiStatus('正在展示信息卡片', { icon: 'tool' });
          window.dispatchEvent(new CustomEvent('dpm:show-card', { detail: cmd.params || {} }));
          break;
        case 'play':
        case 'pause':
        case 'next':
        case 'prev':
          Sfx.tick();
        case 'set_mode':
        case 'play_target':
        case 'minimize':
        case 'settings_changed':
        case 'playlist_changed':
          window.dispatchEvent(new CustomEvent('dpm:media-control', { detail: cmd }));
          break;

        // ── 全局人物识别开关 ──
        case 'vision_set':
          window.dispatchEvent(new CustomEvent('dpm:vision-control', {
            detail: { enabled: Boolean(cmd.params?.enabled) },
          }));
          break;

        // ── AI 助手页操作 ──
        case 'ai_input':
        case 'ai_preset':
        case 'ai_company':
        case 'ai_zone':
          window.dispatchEvent(new CustomEvent('dpm:ai-action', {
            detail: { type: cmd.action.replace('ai_', ''), ...(cmd.params || {}) },
          }));
          break;

        // ── 任务展示页操作（语音页已暂时关闭，voice_* 指令不再处理） ──
        case 'task_refresh':
          window.dispatchEvent(new CustomEvent('dpm:task-control', {
            detail: { action: 'refresh', ...(cmd.params || {}) },
          }));
          break;

        // ── 企业展示墙（/wall）操作 ──
        case 'wall_pause':
        case 'wall_resume':
        case 'wall_speed':
          window.dispatchEvent(new CustomEvent('dpm:wall-control', {
            detail: { action: cmd.action.replace('wall_', ''), ...(cmd.params || {}) },
          }));
          break;

        default:
          break;
      }
    });

    // 离线兜底：AI 对话返回的工具调用在 MQTT 未连接时本地执行
    const onLocal = (e) => {
      const { action, params } = e.detail || {};
      if (action === 'navigate') {
        const path = resolvePage(params?.page);
        if (path) { aiStatus('正在切换页面', { icon: 'page' }); navigate(path); }
      } else if (action === 'control') {
        aiStatus('正在控制媒体播放', { icon: 'tool' });
        window.dispatchEvent(new CustomEvent('dpm:media-control', { detail: { action: params?.action } }));
      } else if (action === 'alert') {
        // 通知本身即展示，无需状态提示
        window.dispatchEvent(new CustomEvent('dpm:alert', { detail: params || {} }));
      } else if (action === 'show_card') {
        aiStatus('正在展示信息卡片', { icon: 'tool' });
        window.dispatchEvent(new CustomEvent('dpm:show-card', { detail: params || {} }));
      }
    };
    window.addEventListener('dpm:mqtt-local', onLocal);
    return () => {
      off();
      window.removeEventListener('dpm:mqtt-local', onLocal);
    };
  }, [navigate, location.pathname]);

  return null;
}