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/api_client.dart';
import '../../core/navigation_provider.dart';
import '../../providers/auth_provider.dart';
import '../../providers/chat_provider.dart';
import '../../providers/data_providers.dart';
import '../../widgets/agent_bar.dart';
import '../../widgets/health_drawer.dart';
import 'widgets/chat_messages_view.dart';

/// 首页——主界面
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;
  bool _showExpandButton = false;

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

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

  void _onScroll() {
    if (_scrollCtrl.offset > 50 && !_showExpandButton) {
      setState(() => _showExpandButton = true);
    } else if (_scrollCtrl.offset <= 50 && _showExpandButton) {
      setState(() => _showExpandButton = false);
    }
  }

  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 selectedAgent = ref.watch(selectedAgentProvider);

    return Scaffold(
      drawer: const HealthDrawer(),
      body: SafeArea(
        child: Stack(children: [
          Column(children: [
            _buildHeader(context),
            if (_taskCardsExpanded) _buildTaskCards(),
            Expanded(child: ChatMessagesView(scrollCtrl: _scrollCtrl, messages: chatState.messages)),
            _buildAgentPanel(context, selectedAgent),
            const AgentBar(),
            _buildInputBar(),
          ]),
          _buildExpandButton(),
        ]),
      ),
    );
  }

  Widget _buildExpandButton() {
    if (!_showExpandButton || _taskCardsExpanded) return const SizedBox.shrink();
    
    return Positioned(
      top: 60,
      right: 16,
      child: AnimatedOpacity(
        opacity: _showExpandButton ? 1.0 : 0.0,
        duration: const Duration(milliseconds: 300),
        child: FloatingActionButton(
          onPressed: () => setState(() => _taskCardsExpanded = true),
          mini: true,
          backgroundColor: const Color(0xFF635BFF),
          child: const Icon(Icons.keyboard_arrow_down, size: 20),
        ),
      ),
    );
  }

  Widget _buildHeader(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
      child: Row(children: [
        Builder(builder: (ctx) => IconButton(
          icon: const Icon(Icons.menu, size: 24),
          onPressed: () => Scaffold.of(ctx).openDrawer(),
        )),
        const Spacer(),
        Text('健康管家', style: Theme.of(context).textTheme.titleLarge),
        const Spacer(),
        const SizedBox(width: 48),
      ]),
    );
  }

  Widget _buildTaskCards() {
    final latestHealth = ref.watch(latestHealthProvider);
    
    return latestHealth.when(
      data: (data) {
        final tasks = _getTaskCards(data);
        if (tasks.isEmpty) return const SizedBox.shrink();
        
        return Container(
          margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
          padding: const EdgeInsets.all(16),
          decoration: BoxDecoration(
            color: const Color(0xFFFEFEFF),
            borderRadius: BorderRadius.circular(24),
            boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(10), blurRadius: 8, offset: const Offset(0, 2))],
          ),
          child: Column(children: [
            Row(children: [
              const Icon(Icons.wb_sunny, size: 20, color: Color(0xFFFFB800)),
              const SizedBox(width: 8),
              Text(_getGreeting(), style: const TextStyle(fontSize: 18, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
              const Spacer(),
              GestureDetector(
                onTap: () => setState(() => _taskCardsExpanded = false),
                child: const Icon(Icons.keyboard_arrow_down, size: 22, color: Color(0xFF999999)),
              ),
            ]),
            const SizedBox(height: 12),
            Column(children: tasks),
          ]),
        );
      },
      loading: () => const SizedBox.shrink(),
      error: (_, __) {
        final tasks = _getTaskCards(const {});
        if (tasks.isEmpty) return const SizedBox.shrink();
        return Container(
          margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
          padding: const EdgeInsets.all(16),
          decoration: BoxDecoration(
            color: const Color(0xFFFEFEFF),
            borderRadius: BorderRadius.circular(24),
            boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(10), blurRadius: 8, offset: const Offset(0, 2))],
          ),
          child: Column(children: [
            Row(children: [
              const Icon(Icons.wb_sunny, size: 20, color: Color(0xFFFFB800)),
              const SizedBox(width: 8),
              Text(_getGreeting(), style: const TextStyle(fontSize: 18, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
              const Spacer(),
              GestureDetector(
                onTap: () => setState(() => _taskCardsExpanded = false),
                child: const Icon(Icons.keyboard_arrow_down, size: 22, color: Color(0xFF999999)),
              ),
            ]),
            const SizedBox(height: 12),
            Column(children: tasks),
          ]),
        );
      },
    );
  }

  String _getGreeting() {
    final hour = DateTime.now().hour;
    if (hour < 6) return '夜深了';
    if (hour < 9) return '早上好';
    if (hour < 12) return '上午好';
    if (hour < 14) return '中午好';
    if (hour < 18) return '下午好';
    if (hour < 22) return '晚上好';
    return '夜深了';
  }

  List<Widget> _getTaskCards(Map<String, dynamic> healthData) {
    final cards = <Widget>[];
    
    cards.add(_buildMedicationCard());
    cards.add(_buildExerciseCard());
    cards.add(_buildMeasurementCard());
    
    final abnormalCards = _buildAbnormalCards(healthData);
    cards.addAll(abnormalCards);
    
    final summaryCard = _buildSummaryCard(healthData);
    if (summaryCard != null) cards.add(summaryCard);
    
    return cards;
  }

  Widget _buildMedicationCard() {
    return _buildTaskCard(
      '💊', 
      '计划 8:00 吃 阿司匹林 100mg', 
      Icons.check_circle_outline, 
      () => _handleMedicationCheck(),
      type: 'medication',
    );
  }

  Widget _buildExerciseCard() {
    return _buildTaskCard(
      '🏃', 
      '今日待运动：散步 30 分钟', 
      Icons.check_circle_outline, 
      () => _handleExerciseCheck(),
      type: 'exercise',
    );
  }

  Widget _buildMeasurementCard() {
    return _buildTaskCard(
      '🩺', 
      '今日待测量：血压', 
      Icons.arrow_forward_ios, 
      () => _textCtrl.text = '血压 ',
      type: 'measurement',
    );
  }

  List<Widget> _buildAbnormalCards(Map<String, dynamic> healthData) {
    final cards = <Widget>[];
    
    final bp = healthData['BloodPressure'];
    if (bp != null && bp is Map) {
      final systolic = bp['systolic'];
      final diastolic = bp['diastolic'];
      if (systolic != null && systolic >= 140) {
        cards.add(_buildTaskCard(
          '⚠️', 
          '昨日血压 ${systolic}/${diastolic ?? '--'}，偏高', 
          Icons.arrow_forward_ios, 
          () => pushRoute(ref, 'trend', params: {'type': 'blood_pressure'}),
          type: 'warning',
          highlight: true,
        ));
      }
    }
    
    final hr = healthData['HeartRate'];
    if (hr != null && hr is Map) {
      final value = hr['value'];
      if (value != null && (value > 100 || value < 60)) {
        cards.add(_buildTaskCard(
          '⚠️', 
          '昨日心率 $value，${value > 100 ? '偏高' : '偏低'}', 
          Icons.arrow_forward_ios, 
          () => pushRoute(ref, 'trend', params: {'type': 'heart_rate'}),
          type: 'warning',
          highlight: true,
        ));
      }
    }
    
    return cards;
  }

  Widget? _buildSummaryCard(Map<String, dynamic> healthData) {
    final values = <String>[];
    
    final bp = healthData['BloodPressure'];
    if (bp != null && bp is Map) {
      final sys = bp['systolic'];
      final dia = bp['diastolic'];
      if (sys != null && dia != null) values.add('血压 $sys/$dia');
    }
    
    final hr = healthData['HeartRate'];
    if (hr != null && hr is Map && hr['value'] != null) {
      values.add('心率 ${hr['value']}');
    }
    
    final glucose = healthData['Glucose'];
    if (glucose != null && glucose is Map && glucose['value'] != null) {
      values.add('血糖 ${glucose['value']}');
    }
    
    if (values.isEmpty) return null;
    
    return _buildTaskCard(
      '📊', 
      '今日已记录：${values.join('、')}', 
      Icons.arrow_forward_ios, 
      () => pushRoute(ref, 'trend', params: {'type': 'blood_pressure'}),
      type: 'summary',
    );
  }

  Widget _buildTaskCard(String icon, String text, IconData actionIcon, VoidCallback onTap, {String type = '', bool highlight = false}) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 6),
      child: Container(
        padding: const EdgeInsets.symmetric(vertical: 8),
        decoration: highlight ? BoxDecoration(
          color: const Color(0xFFFDF2F2),
          borderRadius: BorderRadius.circular(12),
        ) : null,
        child: Row(children: [
          Text(icon, style: const TextStyle(fontSize: 20)),
          const SizedBox(width: 10),
          Expanded(child: Text(text, style: TextStyle(
            fontSize: 14, 
            color: highlight ? const Color(0xFFDC2626) : const Color(0xFF333333),
          ))),
          GestureDetector(
            onTap: onTap,
            child: Icon(actionIcon, size: 20, color: highlight ? const Color(0xFFDC2626) : const Color(0xFF635BFF)),
          ),
        ]),
      ),
    );
  }

  void _handleMedicationCheck() async {
    await ref.read(medicationServiceProvider).confirm('');
    ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
      content: Text('已记录服药 ✅'),
      backgroundColor: Color(0xFF635BFF),
      duration: Duration(seconds: 2),
    ));
  }

  void _handleExerciseCheck() async {
    ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
      content: Text('已完成运动 ✅'),
      backgroundColor: Color(0xFF635BFF),
      duration: Duration(seconds: 2),
    ));
  }

  Widget _buildAgentPanel(BuildContext context, ActiveAgent? agent) {
    if (agent == null) return const SizedBox.shrink();
    
    return AnimatedContainer(
      duration: const Duration(milliseconds: 300),
      curve: Curves.easeInOut,
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFFFEFEFF),
        borderRadius: const BorderRadius.vertical(top: Radius.circular(24)),
        boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(20), blurRadius: 12, offset: const Offset(0, -4))],
      ),
      child: Column(mainAxisSize: MainAxisSize.min, children: [
        _buildAgentPanelHeader(agent),
        const SizedBox(height: 12),
        ..._getAgentButtons(agent),
      ]),
    );
  }

  Widget _buildAgentPanelHeader(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 Column(children: [
      Text(titles[agent] ?? '', style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
      const SizedBox(height: 4),
      Text(tips[agent] ?? '', style: const TextStyle(fontSize: 12, color: Color(0xFF999999))),
    ]);
  }

  List<Widget> _getAgentButtons(ActiveAgent agent) {
    final buttons = <Widget>[];
    if (agent == ActiveAgent.health) {
      buttons.add(_panelBtn('手动录入血压', Icons.favorite));
      buttons.add(_panelBtn('手动录入血糖', Icons.bloodtype));
      buttons.add(_panelBtn('手动录入心率', Icons.monitor_heart));
      buttons.add(_panelBtn('手动录入血氧', Icons.air));
      buttons.add(_panelBtn('手动录入体重', Icons.monitor_weight));
    } else if (agent == ActiveAgent.diet) {
      buttons.add(_panelBtn('拍照', Icons.camera_alt));
      buttons.add(_panelBtn('上传照片', Icons.photo_library));
    } else if (agent == ActiveAgent.medication) {
      buttons.add(_panelBtn('用药管理', Icons.medication));
      buttons.add(_panelBtn('用药提醒', Icons.alarm));
    } else if (agent == ActiveAgent.consultation) {
      buttons.add(_panelBtn('找医生', Icons.person_search));
    } else if (agent == ActiveAgent.exercise) {
      buttons.add(_panelBtn('查看本周计划', Icons.calendar_view_week));
      buttons.add(_panelBtn('创建新计划', Icons.add_circle_outline));
    }
    return buttons;
  }

  Widget _panelBtn(String label, IconData icon) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8),
      child: SizedBox(
        width: double.infinity,
        child: ElevatedButton.icon(
          onPressed: () => _onAgentAction(label),
          icon: Icon(icon, size: 18),
          label: Text(label, style: const TextStyle(fontSize: 14)),
          style: ElevatedButton.styleFrom(
            backgroundColor: const Color(0xFFF5F3FF),
            foregroundColor: const Color(0xFF635BFF),
            elevation: 0,
            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
            padding: const EdgeInsets.symmetric(vertical: 12, horizontal: 16),
          ),
        ),
      ),
    );
  }

  void _onAgentAction(String label) {
    switch (label) {
      case '拍照':
        pushRoute(ref, 'dietCapture');
        break;
      case '上传照片':
        pushRoute(ref, 'dietCapture');
        break;
      case '手动录入血压':
        _textCtrl.text = '血压 ';
        break;
      case '手动录入血糖':
        _textCtrl.text = '血糖 ';
        break;
      case '手动录入心率':
        _textCtrl.text = '心率 ';
        break;
      case '手动录入血氧':
        _textCtrl.text = '血氧 ';
        break;
      case '手动录入体重':
        _textCtrl.text = '体重 ';
        break;
      case '用药管理':
        pushRoute(ref, 'medications');
        break;
      case '找医生':
        pushRoute(ref, 'doctors');
        break;
      case '查看本周计划':
        pushRoute(ref, 'exercisePlan');
        break;
      case '创建新计划':
        pushRoute(ref, 'exercisePlan');
        break;
    }
  }

  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] $baseUrl/api/files/${picked.path.split('/').last}';
      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}';
                  setState(() {});
                }
              },
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildInputBar() {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
      decoration: BoxDecoration(
        color: Colors.white,
        border: Border(top: BorderSide(color: Colors.grey.shade200)),
      ),
      child: Row(children: [
        IconButton(icon: const Icon(Icons.attach_file, size: 24, color: Color(0xFF666666)), onPressed: () => _showAttachmentPicker(context)),
        Expanded(
          child: TextField(
            controller: _textCtrl,
            decoration: const InputDecoration(hintText: '输入你想说的...', contentPadding: EdgeInsets.symmetric(horizontal: 12), border: InputBorder.none),
            onSubmitted: (_) => _sendMessage(),
          ),
        ),
        IconButton(icon: const Icon(Icons.send, size: 24, color: Color(0xFF635BFF)), onPressed: _sendMessage),
      ]),
    );
  }
}