import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:image_picker/image_picker.dart';
import 'package:file_picker/file_picker.dart';
import '../../core/navigation_provider.dart';
import '../../providers/auth_provider.dart';
import '../../providers/chat_provider.dart';
import '../../providers/data_providers.dart';
import '../../widgets/health_drawer.dart';
import 'widgets/chat_messages_view.dart';

class HomePage extends ConsumerStatefulWidget {
  const HomePage({super.key});
  @override ConsumerState<HomePage> createState() => _HomePageState();
}

class _HomePageState extends ConsumerState<HomePage> {
  final _textCtrl = TextEditingController();
  final _scrollCtrl = ScrollController();
  bool _taskCardsExpanded = true;

  @override void initState() { super.initState(); _scrollCtrl.addListener(_onScroll); }
  @override void dispose() { _textCtrl.dispose(); _scrollCtrl.dispose(); super.dispose(); }

  void _onScroll() {}

  void _sendMessage() {
    final text = _textCtrl.text.trim();
    if (text.isEmpty) return;
    _textCtrl.clear();
    ref.read(chatProvider.notifier).sendMessage(text);
  }

  @override Widget build(BuildContext context) {
    final chatState = ref.watch(chatProvider);
    final auth = ref.watch(authProvider);
    final user = auth.user;
    final selectedAgent = ref.watch(selectedAgentProvider);

    return Scaffold(
      drawer: const HealthDrawer(),
      backgroundColor: const Color(0xFFF8F7FF),
      body: SafeArea(
        bottom: false,
        child: Column(children: [
          // ── 顶部栏 ──
          _buildHeader(user),

          // ── 今日任务（可折叠） ──
          _buildTaskCardsArea(),

          // ── 聊天区域（弹性填充剩余空间） ──
          Expanded(child: ChatMessagesView(scrollCtrl: _scrollCtrl, messages: chatState.messages)),

          // ── 智能体选择器（常驻显示） ──
          _buildAgentBar(selectedAgent),

          // ── 选中智能体的操作面板 ──
          if (selectedAgent != null) _buildAgentPanel(context, selectedAgent),

          // ── 输入框 ──
          _buildInputBar(context),
        ]),
      ),
    );
  }

  // ═════════════════════ 顶部栏 ═════════════════════

  Widget _buildHeader(dynamic user) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
      child: Row(children: [
        Builder(builder: (ctx) => GestureDetector(
          onTap: () => Scaffold.of(ctx).openDrawer(),
          child: CircleAvatar(radius: 20, backgroundColor: const Color(0xFFEDEBFF), backgroundImage: user?.avatarUrl != null ? NetworkImage(user!.avatarUrl!) : null, child: user?.avatarUrl == null ? const Icon(Icons.person, size: 24, color: Color(0xFF635BFF)) : null),
        )),
        const SizedBox(width: 10),
        Expanded(child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
          Row(mainAxisSize: MainAxisSize.min, children: [Icon(Icons.smart_toy_outlined, size: 16, color: const Color(0xFF635BFF)), const SizedBox(width: 4), Text('AI 健康管家', style: TextStyle(fontSize: 13, fontWeight: FontWeight.w500, color: Colors.grey[600]))]),
          const SizedBox(height: 2),
          Text('${_getGreeting()}，${user?.name ?? '张三'}！', style: const TextStyle(fontSize: 17, fontWeight: FontWeight.bold, color: Color(0xFF1A1A1A))),
        ])),
        Icon(Icons.notifications_none, size: 22, color: Colors.grey[600]),
      ]),
    );
  }

  String _getGreeting() {
    final hour = DateTime.now().hour;
    if (hour < 9) return '早上好';
    if (hour < 12) return '上午好';
    if (hour < 18) return '下午好';
    return '晚上好';
  }

  // ═════════════════════ 今日任务（可折叠/展开） ═════════════════════

  Widget _buildTaskCardsArea() {
    final latestHealth = ref.watch(latestHealthProvider);

    if (_taskCardsExpanded) {
      return latestHealth.when(
        data: (data) => _taskCardContent(data),
        loading: () => _taskCardContent({}),
        error: (_, __) => _taskCardContent({}),
      );
    }

    // 折叠状态：只显示一行可点击的标题栏
    return GestureDetector(
      onTap: () => setState(() => _taskCardsExpanded = true),
      behavior: HitTestBehavior.opaque,
      child: Container(
        margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 6),
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
        decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16), boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(8), blurRadius: 6, offset: const Offset(0, 1))]),
        child: Row(children: [
          Icon(Icons.assignment_turned_in_outlined, size: 18, color: const Color(0xFF635BFF)),
          const SizedBox(width: 8),
          const Text('今日任务', style: TextStyle(fontSize: 15, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
          const Spacer(),
          Text('点击展开', style: TextStyle(fontSize: 12, color: const Color(0xFF635BFF))),
          Icon(Icons.keyboard_arrow_right, size: 18, color: const Color(0xFF635BFF)),
        ]),
      ),
    );
  }

  Widget _taskCardContent(Map<String, dynamic> healthData) {
    return Container(
      margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 6),
      padding: const EdgeInsets.all(14),
      decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16), boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(8), blurRadius: 6, offset: const Offset(0, 1))]),
      child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
        Row(children: [
          const Text('今日任务', style: TextStyle(fontSize: 15, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
          const Spacer(),
          GestureDetector(onTap: () => setState(() => _taskCardsExpanded = false), child: Row(mainAxisSize: MainAxisSize.min, children: [
            Text('收起', style: TextStyle(fontSize: 12, color: const Color(0xFF999999))),
            Icon(Icons.keyboard_arrow_up, size: 18, color: const Color(0xFF999999)),
          ])),
        ]),
        const SizedBox(height: 10),
        ..._getTodayTasks(healthData),
      ]),
    );
  }

  List<Widget> _getTodayTasks(Map<String, dynamic> healthData) {
    return [
      _taskRow(icon: Icons.medication_rounded, label: '计划 8:00 吃 阿司匹林 100mg', status: 'done', onTap: _handleMedicationCheck),
      _taskRow(icon: Icons.directions_run, label: '今日待运动：散步 30 分钟', status: 'pending', onTap: null),
      _taskRow(icon: Icons.today, label: '今日测量：血压', status: 'pending', onTap: () => _textCtrl.text = '血压 '),
      ..._buildAbnormalRows(healthData),
    ];
  }

  List<Widget> _buildAbnormalRows(Map<String, dynamic> healthData) {
    final rows = <Widget>[];
    final bp = healthData['BloodPressure'];
    if (bp is Map) { final s = bp['systolic']; if (s is int && s >= 140) rows.add(_taskRow(icon: Icons.warning_amber_rounded, label: '血压 $s/${bp['diastolic'] ?? '--'} 偏高', status: 'warning', onTap: () => pushRoute(ref, 'trend', params: {'type': 'blood_pressure'}))); }
    return rows;
  }

  Widget _taskRow({required IconData icon, required String label, required String status, VoidCallback? onTap}) {
    final colors = {'done': const Color(0xFF43A047), 'warning': const Color(0xFFFF9800), 'pending': const Color(0xFF9E9E9E)};
    final icons = {'done': Icons.check_circle, 'warning': Icons.warning, 'pending': Icons.circle_outlined};
    return Padding(
      padding: const EdgeInsets.only(bottom: 10),
      child: GestureDetector(
        behavior: HitTestBehavior.opaque,
        onTap: onTap,
        child: Row(children: [
          Container(width: 30, height: 30, decoration: BoxDecoration(color: const Color(0xFFF5F3FF), borderRadius: BorderRadius.circular(8)), child: Icon(icon, size: 15, color: const Color(0xFF635BFF))),
          const SizedBox(width: 10), Expanded(child: Text(label, style: const TextStyle(fontSize: 13, color: Color(0xFF333333)))),
          Icon(icons[status], size: 18, color: colors[status] ?? Colors.grey),
        ]),
      ),
    );
  }

  void _handleMedicationCheck() async {
    await ref.read(medicationServiceProvider).confirm('');
    if (!mounted) return;
    ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('已记录服药 ✅'), backgroundColor: Color(0xFF635BFF)));
  }

  // ═════════════════════ 智能体选择条（常驻） ═════════════════════

  static final _agentDefs = [
    (ActiveAgent.consultation, '问诊', Icons.chat_bubble_outline),
    (ActiveAgent.health, '记数据', Icons.favorite_border),
    (ActiveAgent.diet, '拍饮食', Icons.restaurant_outlined),
    (ActiveAgent.medication, '药管家', Icons.medication_outlined),
    (ActiveAgent.report, '看报告', Icons.description_outlined),
    (ActiveAgent.exercise, '运动', Icons.directions_run_outlined),
  ];

  Widget _buildAgentBar(ActiveAgent? selected) {
    return Container(
      height: 44,
      padding: const EdgeInsets.symmetric(horizontal: 12),
      child: ListView.separated(
        scrollDirection: Axis.horizontal,
        itemCount: _agentDefs.length,
        separatorBuilder: (_, __) => const SizedBox(width: 6),
        itemBuilder: (_, i) {
          final (agent, label, icon) = _agentDefs[i];
          final isActive = selected == agent;
          return GestureDetector(
            onTap: () {
              final notifier = ref.read(selectedAgentProvider.notifier);
              notifier.select(isActive ? null : agent);
              // 切换智能体时清空聊天
              if (!isActive) ref.read(chatProvider.notifier).setAgent(agent);
            },
            child: Container(
              padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
              decoration: BoxDecoration(
                color: isActive ? const Color(0xFF635BFF) : Colors.white,
                borderRadius: BorderRadius.circular(20),
                border: Border.all(color: isActive ? const Color(0xFF635BFF) : const Color(0xFFE0E0E0)),
              ),
              child: Row(mainAxisSize: MainAxisSize.min, children: [
                Icon(icon, size: 14, color: isActive ? Colors.white : const Color(0xFF666666)),
                const SizedBox(width: 4),
                Text(label, style: TextStyle(fontSize: 12, fontWeight: isActive ? FontWeight.w600 : FontWeight.w500, color: isActive ? Colors.white : const Color(0xFF666666))),
              ]),
            ),
          );
        },
      ),
    );
  }

  // ═════════════════════ 智能体操作面板（选中后显示） ═════════════════════

  Widget _buildAgentPanel(BuildContext context, ActiveAgent agent) {
    final titles = {ActiveAgent.consultation: 'AI 问诊', ActiveAgent.health: '记数据', ActiveAgent.diet: '拍饮食', ActiveAgent.medication: '药管家', ActiveAgent.report: '看报告', ActiveAgent.exercise: '运动计划'};
    final tips = {ActiveAgent.consultation: '或直接对我说你的症状', ActiveAgent.health: '或直接对我说："血压 135/85"', ActiveAgent.diet: '或直接对我说："中午吃了牛肉面"', ActiveAgent.medication: '或直接对我说："医生让我吃阿托伐他汀 20mg"', ActiveAgent.report: '或直接上传报告图片', ActiveAgent.exercise: '或直接对我说："每周一三五散步 30 分钟"'};

    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
      decoration: BoxDecoration(color: Colors.white, border: Border(top: BorderSide(color: const Color(0xFFEEEEEE)))),
      child: Column(mainAxisSize: MainAxisSize.min, children: [
        Row(children: [
          Text(titles[agent] ?? '', style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
          const SizedBox(width: 6),
          Expanded(child: Text(tips[agent] ?? '', style: TextStyle(fontSize: 11, color: Colors.grey[500]))),
          GestureDetector(onTap: () => ref.read(selectedAgentProvider.notifier).select(null), child: Icon(Icons.close, size: 18, color: Colors.grey[400])),
        ]),
        const SizedBox(height: 8),
        SingleChildScrollView(scrollDirection: Axis.horizontal, child: Row(children: _getAgentButtons(agent))),
      ]));
  }

  List<Widget> _getAgentButtons(ActiveAgent agent) {
    switch (agent) {
      case ActiveAgent.health: return [_agentBtn('录入血压', Icons.favorite), _agentBtn('录入血糖', Icons.bloodtype), _agentBtn('录入心率', Icons.monitor_heart), _agentBtn('录入血氧', Icons.air), _agentBtn('录入体重', Icons.monitor_weight)];
      case ActiveAgent.diet: return [_agentBtn('拍照识别', Icons.camera_alt), _agentBtn('上传照片', Icons.photo_library)];
      case ActiveAgent.medication: return [_agentBtn('用药管理', Icons.medication), _agentBtn('用药提醒', Icons.alarm)];
      case ActiveAgent.consultation: return [_agentBtn('找医生', Icons.person_search)];
      case ActiveAgent.exercise: return [_agentBtn('本周计划', Icons.calendar_view_week), _agentBtn('新建计划', Icons.add_circle_outline)];
      default: return [];
    }
  }

  Widget _agentBtn(String label, IconData icon) {
    return Padding(
      padding: const EdgeInsets.only(right: 8),
      child: ElevatedButton.icon(
        onPressed: () => _onAgentAction(label),
        icon: Icon(icon, size: 14),
        label: Text(label, style: const TextStyle(fontSize: 12)),
        style: ElevatedButton.styleFrom(backgroundColor: const Color(0xFFF5F3FF), foregroundColor: const Color(0xFF635BFF), elevation: 0, shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)), padding: const EdgeInsets.symmetric(vertical: 8, horizontal: 12)),
      ),
    );
  }

  void _onAgentAction(String label) {
    switch (label) {
      case '拍照识别': case '上传照片': pushRoute(ref, 'dietCapture');
      case '录入血压': _textCtrl.text = '血压 ';
      case '录入血糖': _textCtrl.text = '血糖 ';
      case '录入心率': _textCtrl.text = '心率 ';
      case '录入血氧': _textCtrl.text = '血氧 ';
      case '录入体重': _textCtrl.text = '体重 ';
      case '用药管理': pushRoute(ref, 'medications');
      case '找医生': pushRoute(ref, 'doctors');
      case '本周计划': case '新建计划': pushRoute(ref, 'exercisePlan');
    }
  }

  Future<void> _pickImage(ImageSource source) async {
    final picker = ImagePicker();
    final picked = await picker.pickImage(source: source, imageQuality: 85);
    if (picked != null) { final token = await ref.read(apiClientProvider).accessToken; if (token == null) return; _textCtrl.text = '[图片已上传]'; if (mounted) setState(() {}); }
  }

  void _showAttachmentPicker(BuildContext context) {
    showModalBottomSheet(context: context, builder: (ctx) => SafeArea(child: Wrap(children: [
      ListTile(leading: const Icon(Icons.camera_alt), title: const Text('拍照'), onTap: () { Navigator.pop(ctx); _pickImage(ImageSource.camera); }),
      ListTile(leading: const Icon(Icons.photo_library), title: const Text('从相册选'), onTap: () { Navigator.pop(ctx); _pickImage(ImageSource.gallery); }),
      ListTile(leading: const Icon(Icons.attach_file), title: const Text('传文件'), onTap: () async { Navigator.pop(ctx); final result = await FilePicker.platform.pickFiles(); if (result != null && result.files.isNotEmpty) { _textCtrl.text = '[文件已选择] ${result.files.first.name}'; if (mounted) setState(() {}); }}),
    ])));
  }

  Widget _buildInputBar(BuildContext context) {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
      decoration: BoxDecoration(color: Colors.white, border: Border(top: BorderSide(color: const Color(0xFFEEEEEE)))),
      child: Row(children: [
        IconButton(icon: const Icon(Icons.attach_file, size: 22, color: Color(0xFF666666)), onPressed: () => _showAttachmentPicker(context)),
        Expanded(child: TextField(controller: _textCtrl, decoration: InputDecoration(hintText: '输入你想说的...', contentPadding: const EdgeInsets.symmetric(horizontal: 10), border: InputBorder.none, isDense: true), onSubmitted: (_) => _sendMessage())),
        IconButton(icon: const Icon(Icons.send, size: 22, color: Color(0xFF635BFF)), onPressed: _sendMessage),
      ]),
    );
  }
}