import 'dart:convert';
import 'dart:io';
import 'package:dio/dio.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:image_picker/image_picker.dart';
import '../../core/navigation_provider.dart';
import '../../core/app_colors.dart';
import '../../core/app_theme.dart';
import '../../providers/auth_provider.dart';
import '../../utils/sse_handler.dart';

final dietProvider = NotifierProvider<DietNotifier, DietState>(DietNotifier.new);

class DietState {
  final String? imagePath;
  final List<FoodItem> foods;
  final String mealType;
  final bool isAnalyzing;
  final int? healthScore;
  final String? errorMessage;
  final String? commentary;

  DietState({
    this.imagePath,
    this.foods = const [],
    this.mealType = 'lunch',
    this.isAnalyzing = false,
    this.healthScore,
    this.errorMessage,
    this.commentary,
  });

  DietState copyWith({
    String? imagePath,
    List<FoodItem>? foods,
    String? mealType,
    bool? isAnalyzing,
    int? healthScore,
    String? errorMessage,
    String? commentary,
  }) {
    return DietState(
      imagePath: imagePath ?? this.imagePath,
      foods: foods ?? this.foods,
      mealType: mealType ?? this.mealType,
      isAnalyzing: isAnalyzing ?? this.isAnalyzing,
      healthScore: healthScore ?? this.healthScore,
      errorMessage: errorMessage ?? this.errorMessage,
      commentary: commentary ?? this.commentary,
    );
  }
}

class FoodItem {
  final String id;
  String name;
  String portion;
  int calories;
  bool selected;

  FoodItem({
    required this.id,
    required this.name,
    required this.portion,
    required this.calories,
    this.selected = true,
  });
}

class DietNotifier extends Notifier<DietState> {
  @override
  DietState build() => DietState();

  void setImage(String path) {
    state = state.copyWith(imagePath: path);
  }

  Future<void> analyzeImage() async {
    state = state.copyWith(isAnalyzing: true, errorMessage: null);
    try {
      final api = ref.read(apiClientProvider);
      final path = state.imagePath!;
      final imageFile = File(path);
      final formData = FormData.fromMap({
        'images': await MultipartFile.fromFile(imageFile.path, filename: imageFile.path.split('/').last),
      });
      final res = await api.dio.post('/api/ai/analyze-food-image', data: formData);
      final data = res.data;
      if (data['code'] != 0) {
        state = state.copyWith(isAnalyzing: false, errorMessage: data['message'] ?? '识别失败');
        return;
      }
      final raw = data['data'] as String? ?? '[]';
      final foods = _parseFoodItems(raw);
      state = state.copyWith(foods: foods, isAnalyzing: false, healthScore: foods.isNotEmpty ? 3 : null);
      if (foods.isNotEmpty) _fetchCommentary(foods);
    } catch (e) {
      state = state.copyWith(isAnalyzing: false, errorMessage: '识别失败，请重试');
    }
  }

  Future<void> _fetchCommentary(List<FoodItem> foods) async {
    try {
      final api = ref.read(apiClientProvider);
      final token = await api.accessToken;
      if (token == null) return;
      final names = foods.map((f) => '${f.name}(${f.portion},${f.calories}kcal)').join('、');
      final stream = SseHandler.connect(
        agentType: 'default',
        message: '我刚才吃了这些：$names。请结合我的健康档案，给我简短的饮食评价和建议（50字以内）。',
        token: token,
      );
      String text = '';
      await for (final event in stream) {
        if (event['action'] == 'answer') text += (event['data'] as String?) ?? '';
        if (event['action'] == 'status') {
          if (text.isNotEmpty) state = state.copyWith(commentary: text.trim());
        }
      }
    } catch (e) {
      debugPrint('[Diet] 获取饮食点评失败: $e');
    }
  }

  List<FoodItem> _parseFoodItems(String raw) {
    var json = raw.trim();
    if (json.startsWith('```')) {
      final start = json.indexOf('\n');
      if (start != -1) json = json.substring(start + 1);
      final end = json.lastIndexOf('```');
      if (end != -1) json = json.substring(0, end);
      json = json.trim();
    }
    try {
      final list = jsonDecode(json) as List;
      return list.asMap().entries.map((e) {
        final item = e.value as Map<String, dynamic>;
        return FoodItem(
          id: 'food_${DateTime.now().millisecondsSinceEpoch}_${e.key}',
          name: item['name']?.toString() ?? '未知食物',
          portion: item['portion']?.toString() ?? '',
          calories: (item['calories'] as num?)?.toInt() ?? 0,
          selected: true,
        );
      }).toList();
    } catch (_) {
      return [
        FoodItem(id: 'food_${DateTime.now().millisecondsSinceEpoch}', name: '识别结果（手动编辑）', portion: raw.length > 50 ? raw.substring(0, 50) : raw, calories: 0, selected: true),
      ];
    }
  }

  void updateFoodName(String id, String name) { final foods = state.foods.map((f) => f.id == id ? FoodItem(id: f.id, name: name, portion: f.portion, calories: f.calories, selected: f.selected) : f).toList(); state = state.copyWith(foods: foods); }
  void updateFoodPortion(String id, String portion) { final foods = state.foods.map((f) => f.id == id ? FoodItem(id: f.id, name: f.name, portion: portion, calories: f.calories, selected: f.selected) : f).toList(); state = state.copyWith(foods: foods); }
  void updateFoodCalories(String id, int calories) { final foods = state.foods.map((f) => f.id == id ? FoodItem(id: f.id, name: f.name, portion: f.portion, calories: calories, selected: f.selected) : f).toList(); state = state.copyWith(foods: foods); }
  void toggleFood(String id) { final foods = state.foods.map((f) => f.id == id ? FoodItem(id: f.id, name: f.name, portion: f.portion, calories: f.calories, selected: !f.selected) : f).toList(); state = state.copyWith(foods: foods); }
  void addFood() { final newId = '${DateTime.now().millisecondsSinceEpoch}'; state = state.copyWith(foods: [...state.foods, FoodItem(id: newId, name: '新食物', portion: '', calories: 100)]); }
  void removeFood(String id) { state = state.copyWith(foods: state.foods.where((f) => f.id != id).toList()); }
  void setMealType(String type) { state = state.copyWith(mealType: type); }
  void reset() { state = DietState(); }

  Future<void> saveRecord() async {
    final selectedFoods = state.foods.where((f) => f.selected).toList();
    if (selectedFoods.isEmpty) return;
    final api = ref.read(apiClientProvider);
    final mealMap = {'breakfast': 'Breakfast', 'lunch': 'Lunch', 'dinner': 'Dinner', 'snack': 'Snack'};
    final totalCal = selectedFoods.fold<int>(0, (s, f) => s + f.calories);
    await api.post('/api/diet-records', data: {
      'mealType': mealMap[state.mealType] ?? 'Lunch',
      'totalCalories': totalCal,
      'healthScore': state.healthScore ?? 3,
      'recordedAt': DateTime.now().toIso8601String().substring(0, 10),
      'foodItems': selectedFoods.asMap().entries.map((e) => {'name': e.value.name, 'portion': e.value.portion, 'calories': e.value.calories, 'sortOrder': e.key}).toList(),
    });
  }
}

// ─────────── 饮食主题色（暖橙系，不再用紫色）───────────
const _dietAccent = Color(0xFFF0A060);
const _dietAccentLight = Color(0xFFFFF2E8);
const _dietBg = Color(0xFFFFFBF7);

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

class _DietCapturePageState extends ConsumerState<DietCapturePage> {
  @override void initState() { super.initState(); }

  @override
  Widget build(BuildContext context) {
    final state = ref.watch(dietProvider);
    return Scaffold(
      backgroundColor: _dietBg,
      appBar: AppBar(
        backgroundColor: Colors.white,
        title: const Text('饮食分析', style: TextStyle(fontSize: 20, fontWeight: FontWeight.w600)),
        centerTitle: true,
      ),
      body: state.imagePath == null
          ? const Center(child: Text('请从首页拍摄或选择食物照片', style: TextStyle(color: AppColors.textSecondary, fontSize: 16)))
          : _buildResultView(context, ref),
    );
  }

  Widget _buildResultView(BuildContext context, WidgetRef ref) {
    final state = ref.watch(dietProvider);
    final screenW = MediaQuery.of(context).size.width;

    return Container(
      decoration: const BoxDecoration(gradient: LinearGradient(colors: [_dietBg, Color(0xFFFFF8F2)])),
      child: SingleChildScrollView(
        padding: const EdgeInsets.fromLTRB(16, 12, 16, 24),
        child: Column(children: [
          // 图片自适应显示
          ClipRRect(
            borderRadius: BorderRadius.circular(16),
            child: Image.file(
              File(state.imagePath!),
              width: screenW - 32,
              height: 220,
              fit: BoxFit.cover,
            ),
          ),
          const SizedBox(height: 16),
          _buildMealSelector(ref),
          const SizedBox(height: 16),
          if (state.isAnalyzing)
            _buildAnalyzing(state)
          else ...[
            if (state.foods.isNotEmpty) ...[
              _buildFoodList(ref),
              const SizedBox(height: 16),
              _buildNutritionCard(ref),
              if (state.commentary != null && state.commentary!.isNotEmpty) ...[
                const SizedBox(height: 16),
                _buildAiCommentary(state.commentary!),
              ],
            ],
            const SizedBox(height: 20),
            _buildSaveButton(),
          ],
        ]),
      ),
    );
  }

  // ─────────── 餐次选择器 ───────────
  Widget _buildMealSelector(WidgetRef ref) {
    final state = ref.watch(dietProvider);
    final meals = [
      ('🌅', '早餐', 'breakfast'),
      ('☀️', '午餐', 'lunch'),
      ('🌙', '晚餐', 'dinner'),
      ('🍪', '加餐', 'snack'),
    ];
    return Container(
      padding: const EdgeInsets.all(4),
      decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(14)),
      child: Row(
        children: meals.map((m) {
          final sel = state.mealType == m.$3;
          return Expanded(
            child: GestureDetector(
              onTap: () => ref.read(dietProvider.notifier).setMealType(m.$3),
              child: AnimatedContainer(
                duration: const Duration(milliseconds: 200),
                padding: const EdgeInsets.symmetric(vertical: 12),
                decoration: BoxDecoration(
                  color: sel ? _dietAccentLight : Colors.white,
                  borderRadius: BorderRadius.circular(12),
                ),
                child: Column(mainAxisSize: MainAxisSize.min, children: [
                  Text(m.$1, style: const TextStyle(fontSize: 22)),
                  const SizedBox(height: 2),
                  Text(m.$2, style: TextStyle(fontSize: 14, fontWeight: FontWeight.w600, color: sel ? _dietAccent : AppColors.textHint)),
                ]),
              ),
            ),
          );
        }).toList(),
      ),
    );
  }

  // ─────────── 分析中 ───────────
  Widget _buildAnalyzing(DietState state) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 40),
      child: Column(children: [
        const SizedBox(width: 48, height: 48, child: CircularProgressIndicator(strokeWidth: 3, color: _dietAccent)),
        const SizedBox(height: 16),
        const Text('正在识别食物...', style: TextStyle(fontSize: 16, color: AppColors.textSecondary)),
        if (state.errorMessage != null) ...[
          const SizedBox(height: 8),
          Text(state.errorMessage!, style: const TextStyle(fontSize: 14, color: AppColors.error), textAlign: TextAlign.center),
        ],
      ]),
    );
  }

  // ─────────── 食物列表 ───────────
  Widget _buildFoodList(WidgetRef ref) {
    final state = ref.watch(dietProvider);
    final totalCal = state.foods.where((f) => f.selected).fold(0, (s, f) => s + f.calories);
    return Container(
      padding: const EdgeInsets.all(14),
      decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16), boxShadow: AppColors.cardShadowLight),
      child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
        Row(children: [
          Container(width: 4, height: 16, decoration: BoxDecoration(color: _dietAccent, borderRadius: BorderRadius.circular(2))),
          const SizedBox(width: 8),
          const Text('识别结果', style: TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: AppColors.textPrimary)),
          const Spacer(),
          Container(
            padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
            decoration: BoxDecoration(color: const Color(0xFFFFF3E0), borderRadius: BorderRadius.circular(8)),
            child: Text('共 $totalCal kcal', style: const TextStyle(fontSize: 15, fontWeight: FontWeight.w600, color: Color(0xFFE68A00))),
          ),
        ]),
        const SizedBox(height: 10),
        ...state.foods.map((food) => _foodItemTile(ref, food)),
        const SizedBox(height: 4),
        Center(
          child: TextButton.icon(
            onPressed: () => ref.read(dietProvider.notifier).addFood(),
            icon: const Icon(Icons.add_circle_outline, size: 20, color: _dietAccent),
            label: const Text('添加食物', style: TextStyle(fontSize: 15, color: _dietAccent)),
          ),
        ),
      ]),
    );
  }

  Widget _foodItemTile(WidgetRef ref, FoodItem food) {
    return Container(
      margin: const EdgeInsets.only(bottom: 8),
      padding: const EdgeInsets.all(10),
      decoration: BoxDecoration(
        color: AppColors.background,
        borderRadius: BorderRadius.circular(12),
        border: Border.all(color: food.selected ? _dietAccent.withAlpha(60) : AppColors.borderLight),
      ),
      child: Row(children: [
        GestureDetector(
          onTap: () => ref.read(dietProvider.notifier).toggleFood(food.id),
          child: Container(
            width: 22, height: 22,
            decoration: BoxDecoration(
              shape: BoxShape.circle,
              color: food.selected ? _dietAccent : Colors.white,
              border: Border.all(color: food.selected ? _dietAccent : AppColors.border, width: 2),
            ),
            child: food.selected ? const Icon(Icons.check, size: 14, color: Colors.white) : null,
          ),
        ),
        const SizedBox(width: 10),
        Expanded(
          child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
            _compactField(food.name, (v) => ref.read(dietProvider.notifier).updateFoodName(food.id, v), style: const TextStyle(fontSize: 17, fontWeight: FontWeight.w600)),
            const SizedBox(height: 4),
            Row(children: [
              Expanded(flex: 3, child: _compactField(food.portion, (v) => ref.read(dietProvider.notifier).updateFoodPortion(food.id, v), hint: '份量', style: const TextStyle(fontSize: 14, color: AppColors.textSecondary))),
              const SizedBox(width: 8),
              Expanded(flex: 2, child: Row(children: [
                Expanded(child: _compactField(food.calories.toString(), (v) => ref.read(dietProvider.notifier).updateFoodCalories(food.id, int.tryParse(v) ?? 0), hint: '0', style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w600, color: Color(0xFFE68A00)), align: TextAlign.right, keyboardType: TextInputType.number)),
                const SizedBox(width: 2),
                const Text('kcal', style: TextStyle(fontSize: 13, color: AppColors.textHint)),
              ])),
            ]),
          ]),
        ),
        GestureDetector(
          onTap: () => ref.read(dietProvider.notifier).removeFood(food.id),
          child: const Icon(Icons.close, size: 18, color: AppColors.textHint),
        ),
      ]),
    );
  }

  Widget _compactField(String value, ValueChanged<String> cb, {String? hint, TextStyle? style, TextAlign align = TextAlign.start, TextInputType? keyboardType}) {
    return TextField(
      controller: TextEditingController(text: value),
      onChanged: cb,
      keyboardType: keyboardType,
      textAlign: align,
      style: style ?? const TextStyle(fontSize: 15),
      decoration: InputDecoration(isDense: true, contentPadding: EdgeInsets.zero, border: InputBorder.none, hintText: hint, hintStyle: const TextStyle(fontSize: 14, color: AppColors.textHint)),
    );
  }

  // ─────────── 营养摘要 ───────────
  Widget _buildNutritionCard(WidgetRef ref) {
    final state = ref.watch(dietProvider);
    final totalCal = state.foods.where((f) => f.selected).fold(0, (s, f) => s + f.calories);
    return Container(
      padding: const EdgeInsets.all(18),
      decoration: BoxDecoration(
        color: const Color(0xFFFFF8F0),
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: const Color(0xFFFFE8D0)),
      ),
      child: Row(children: [
        SizedBox(
          width: 56, height: 56,
          child: Stack(alignment: Alignment.center, children: [
            SizedBox(width: 56, height: 56, child: CircularProgressIndicator(value: (totalCal / 700).clamp(0.0, 1.0), strokeWidth: 4, backgroundColor: const Color(0xFFFFE8D0), color: _dietAccent)),
            Column(mainAxisSize: MainAxisSize.min, children: [
              Text('$totalCal', style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w800, color: _dietAccent)),
              const Text('kcal', style: TextStyle(fontSize: 12, color: AppColors.textSecondary)),
            ]),
          ]),
        ),
        const SizedBox(width: 16),
        Expanded(
          child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
            const Text('本餐热量', style: TextStyle(fontSize: 16, fontWeight: FontWeight.w600, color: AppColors.textPrimary)),
            const SizedBox(height: 6),
            Row(children: [
              _macro('碳水', 0.55, const Color(0xFFF5A623)),
              const SizedBox(width: 8),
              _macro('蛋白', 0.25, const Color(0xFF4A90D9)),
              const SizedBox(width: 8),
              _macro('脂肪', 0.20, const Color(0xFFE8686A)),
            ]),
          ]),
        ),
      ]),
    );
  }

  Widget _macro(String label, double ratio, Color color) {
    return Expanded(
      child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
        Row(children: [Container(width: 6, height: 6, decoration: BoxDecoration(color: color, shape: BoxShape.circle)), const SizedBox(width: 4), Text(label, style: const TextStyle(fontSize: 12, color: AppColors.textSecondary))]),
        const SizedBox(height: 3),
        ClipRRect(borderRadius: BorderRadius.circular(2), child: LinearProgressIndicator(value: ratio, minHeight: 4, backgroundColor: AppColors.borderLight, color: color)),
      ]),
    );
  }

  // ─────────── AI 点评 ───────────
  Widget _buildAiCommentary(String text) {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: const Color(0xFFFFFBF5),
        borderRadius: BorderRadius.circular(16),
        border: Border.all(color: const Color(0xFFFFE8C0)),
      ),
      child: Row(crossAxisAlignment: CrossAxisAlignment.start, children: [
        Container(
          width: 36, height: 36,
          decoration: BoxDecoration(color: _dietAccentLight, borderRadius: BorderRadius.circular(10)),
          child: const Icon(Icons.auto_awesome, size: 20, color: _dietAccent),
        ),
        const SizedBox(width: 12),
        Expanded(child: Text(text, style: const TextStyle(fontSize: 16, color: AppColors.textPrimary, height: 1.6))),
      ]),
    );
  }

  // ─────────── 保存按钮 ───────────
  Widget _buildSaveButton() {
    return SizedBox(
      width: double.infinity,
      height: 52,
      child: ElevatedButton.icon(
        onPressed: () async {
          try {
            await ref.read(dietProvider.notifier).saveRecord();
            if (mounted) popRoute(ref);
          } catch (e) { debugPrint('[Diet] 保存记录失败: $e'); }
        },
        icon: const Icon(Icons.check_circle_outline, size: 22),
        label: const Text('保存记录', style: TextStyle(fontSize: 17, fontWeight: FontWeight.w600)),
        style: ElevatedButton.styleFrom(
          backgroundColor: _dietAccent,
          foregroundColor: Colors.white,
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(14)),
        ),
      ),
    );
  }
}