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 '../../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;

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

  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: Column(children: [
          _buildHeader(context),
          if (_taskCardsExpanded) _buildTaskCards(chatState),
          Expanded(child: ChatMessagesView(scrollCtrl: _scrollCtrl, messages: chatState.messages)),
          if (selectedAgent != null) _buildAgentPanel(context, selectedAgent),
          const AgentBar(),
          _buildInputBar(),
        ]),
      ),
    );
  }

  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(ChatState chatState) {
    return GestureDetector(
      onVerticalDragUpdate: (d) { if (d.delta.dy < -10) setState(() => _taskCardsExpanded = false); },
      child: Container(
        margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
        padding: const EdgeInsets.all(12),
        decoration: BoxDecoration(
          color: const Color(0xFFEDEBFF),
          borderRadius: BorderRadius.circular(12),
        ),
        child: Column(children: [
          Row(children: [
            const Icon(Icons.wb_sunny, size: 18, color: Color(0xFF635BFF)),
            const SizedBox(width: 8),
            const Text('早上好！', style: TextStyle(fontSize: 18, fontWeight: FontWeight.w600)),
            const Spacer(),
            GestureDetector(
              onTap: () => setState(() => _taskCardsExpanded = false),
              child: const Icon(Icons.keyboard_arrow_up, size: 20, color: Color(0xFF666666)),
            ),
          ]),
          if (chatState.noticeText != null)
            Padding(
              padding: const EdgeInsets.only(top: 8),
              child: Text(chatState.noticeText!, style: const TextStyle(fontSize: 14, color: Color(0xFF666666))),
            ),
        ]),
      ),
    );
  }

  Widget _buildAgentPanel(BuildContext context, ActiveAgent agent) {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: Colors.white,
        borderRadius: const BorderRadius.vertical(top: Radius.circular(16)),
        boxShadow: [BoxShadow(color: const Color(0xFF635BFF).withAlpha(20), blurRadius: 8, offset: const Offset(0, -2))],
      ),
      child: Column(mainAxisSize: MainAxisSize.min, children: _getAgentButtons(agent)),
    );
  }

  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));
    } 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: OutlinedButton.icon(
          onPressed: () => _onAgentAction(label),
          icon: Icon(icon, size: 20),
          label: Text(label),
          style: OutlinedButton.styleFrom(
            foregroundColor: const Color(0xFF635BFF),
            side: const BorderSide(color: Color(0xFF635BFF)),
            shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(24)),
            padding: const EdgeInsets.symmetric(vertical: 12),
          ),
        ),
      ),
    );
  }

  void _onAgentAction(String label) {
    switch (label) {
      case '拍照':
        _pickImage(ImageSource.camera);
        break;
      case '上传照片':
        _pickImage(ImageSource.gallery);
        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 '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),
      ]),
    );
  }
}