import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:lucide_icons_flutter/lucide_icons.dart';
import '../../../core/theme/app_theme.dart';
import '../../../core/theme/app_spacing.dart';
import '../../../core/theme/app_theme_extension.dart';
import '../../../data/services/asset_service.dart';

/// 盈亏分析页面 - 月度盈亏日历
class ProfitAnalysisPage extends StatefulWidget {
  const ProfitAnalysisPage({super.key});

  @override
  State<ProfitAnalysisPage> createState() => _ProfitAnalysisPageState();
}

class _ProfitAnalysisPageState extends State<ProfitAnalysisPage> {
  late DateTime _currentMonth;
  Map<String, dynamic>? _profitData;
  bool _isLoading = false;

  @override
  void initState() {
    super.initState();
    _currentMonth = DateTime.now();
    WidgetsBinding.instance.addPostFrameCallback((_) => _loadProfit());
  }

  // ============================================
  // 数据加载
  // ============================================

  Future<void> _loadProfit() async {
    setState(() => _isLoading = true);
    try {
      final assetService = context.read<AssetService>();
      final response = await assetService.getDailyProfit(
        year: _currentMonth.year,
        month: _currentMonth.month,
      );
      if (mounted) {
        setState(() {
          _profitData = response.data;
          _isLoading = false;
        });
      }
    } catch (_) {
      if (mounted) setState(() => _isLoading = false);
    }
  }

  void _previousMonth() {
    setState(() {
      _currentMonth = DateTime(_currentMonth.year, _currentMonth.month - 1);
    });
    _loadProfit();
  }

  void _nextMonth() {
    setState(() {
      _currentMonth = DateTime(_currentMonth.year, _currentMonth.month + 1);
    });
    _loadProfit();
  }

  // ============================================
  // 盈亏数据解析
  // ============================================

  double? _getDayProfit(int day) {
    if (_profitData == null) return null;
    final daily = _profitData!['daily'] as Map<String, dynamic>?;
    if (daily == null) return null;
    final dateStr =
        '${_currentMonth.year}-${_currentMonth.month.toString().padLeft(2, '0')}-${day.toString().padLeft(2, '0')}';
    final value = daily[dateStr];
    if (value == null) return null;
    return (value is num) ? value.toDouble() : double.tryParse(value.toString());
  }

  double get _monthProfit {
    if (_profitData == null) return 0;
    final value = _profitData!['totalProfit'];
    if (value == null) return 0;
    return (value is num) ? value.toDouble() : double.tryParse(value.toString()) ?? 0;
  }

  // ============================================
  // 构建 UI
  // ============================================

  @override
  Widget build(BuildContext context) {
    final now = DateTime.now();
    final isCurrentMonth =
        _currentMonth.year == now.year && _currentMonth.month == now.month;

    return Scaffold(
      backgroundColor: context.colors.surface,
      appBar: AppBar(
        title: const Text('盈亏分析'),
        backgroundColor: context.colors.surface,
        elevation: 0,
        scrolledUnderElevation: 0,
        centerTitle: true,
      ),
      body: SingleChildScrollView(
        padding: EdgeInsets.all(AppSpacing.lg),
        child: Container(
          padding: EdgeInsets.all(AppSpacing.lg),
          decoration: BoxDecoration(
            color: context.appColors.surfaceCard,
            borderRadius: BorderRadius.circular(AppRadius.xl),
            border: Border.all(color: context.appColors.ghostBorder),
          ),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              // 月度盈亏摘要
              _buildSummarySection(),
              SizedBox(height: AppSpacing.md),

              // 月份导航
              _buildMonthNavigation(isCurrentMonth),
              SizedBox(height: AppSpacing.sm),

              // 星期标题
              _buildWeekdayHeaders(),
              SizedBox(height: AppSpacing.xs),

              // 日历网格
              if (_isLoading)
                _buildLoadingIndicator()
              else
                ..._buildCalendarGrid(
                  now,
                  isCurrentMonth,
                ),
            ],
          ),
        ),
      ),
    );
  }

  /// 月度盈亏摘要
  Widget _buildSummarySection() {
    final upColor = context.appColors.up;
    final downColor = context.appColors.down;
    final isProfit = _monthProfit >= 0;
    final color = _isLoading ? context.colors.onSurfaceVariant : (isProfit ? upColor : downColor);

    return Column(
      children: [
        Text(
          '月度盈亏',
          style: AppTextStyles.bodyMedium(context).copyWith(
            color: context.colors.onSurfaceVariant,
          ),
        ),
        SizedBox(height: AppSpacing.xs),
        Text(
          _isLoading
              ? '--'
              : '${isProfit ? '+' : ''}${_monthProfit.toStringAsFixed(2)} USDT',
          style: AppTextStyles.displaySmall(context).copyWith(
            fontWeight: FontWeight.bold,
            color: color,
          ),
        ),
      ],
    );
  }

  /// 月份导航行
  Widget _buildMonthNavigation(bool isCurrentMonth) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        // 上一月
        GestureDetector(
          onTap: _previousMonth,
          child: Container(
            padding: EdgeInsets.all(AppSpacing.xs + 1),
            decoration: BoxDecoration(
              color: context.colors.surfaceContainerHigh,
              borderRadius: BorderRadius.circular(AppRadius.sm),
            ),
            child: Icon(
              LucideIcons.chevronLeft,
              size: 16,
              color: context.colors.onSurfaceVariant,
            ),
          ),
        ),
        // 当前年月
        Text(
          '${_currentMonth.year}年${_currentMonth.month}月',
          style: AppTextStyles.headlineMedium(context).copyWith(
            fontWeight: FontWeight.bold,
          ),
        ),
        // 下一月（当前月禁用）
        GestureDetector(
          onTap: isCurrentMonth ? null : _nextMonth,
          child: Container(
            padding: EdgeInsets.all(AppSpacing.xs + 1),
            decoration: BoxDecoration(
              color: isCurrentMonth
                  ? context.colors.surfaceContainerHigh.withValues(alpha: 0.5)
                  : context.colors.surfaceContainerHigh,
              borderRadius: BorderRadius.circular(AppRadius.sm),
            ),
            child: Icon(
              LucideIcons.chevronRight,
              size: 16,
              color: isCurrentMonth
                  ? context.colors.onSurfaceVariant.withValues(alpha: 0.4)
                  : context.colors.onSurfaceVariant,
            ),
          ),
        ),
      ],
    );
  }

  /// 星期标题行
  Widget _buildWeekdayHeaders() {
    return Row(
      children: ['一', '二', '三', '四', '五', '六', '日'].map((d) {
        return Expanded(
          child: Center(
            child: Text(
              d,
              style: AppTextStyles.bodySmall(context).copyWith(
                fontWeight: FontWeight.w500,
                color: context.colors.onSurfaceVariant.withValues(alpha: 0.6),
              ),
            ),
          ),
        );
      }).toList(),
    );
  }

  /// 加载指示器
  Widget _buildLoadingIndicator() {
    return Padding(
      padding: EdgeInsets.symmetric(vertical: AppSpacing.xxl),
      child: Center(
        child: SizedBox(
          width: 20,
          height: 20,
          child: CircularProgressIndicator(
            strokeWidth: 2,
            color: context.colors.primary,
          ),
        ),
      ),
    );
  }

  /// 日历网格
  List<Widget> _buildCalendarGrid(
    DateTime now,
    bool isCurrentMonth,
  ) {
    final upColor = context.appColors.up;
    final downColor = context.appColors.down;
    final firstDayOfMonth = DateTime(_currentMonth.year, _currentMonth.month, 1);
    final daysInMonth =
        DateTime(_currentMonth.year, _currentMonth.month + 1, 0).day;
    final startWeekday = firstDayOfMonth.weekday;

    final List<Widget> rows = [];
    List<Widget> cells = [];

    // 填充月初空白
    for (int i = 1; i < startWeekday; i++) {
      cells.add(const Expanded(child: SizedBox.shrink()));
    }

    // 填充每天
    for (int day = 1; day <= daysInMonth; day++) {
      final profit = _getDayProfit(day);
      final isToday = isCurrentMonth && day == now.day;
      final hasProfit = profit != null && profit != 0;

      cells.add(
        Expanded(
          child: AspectRatio(
            aspectRatio: 1,
            child: Container(
              margin: EdgeInsets.all(1),
              decoration: BoxDecoration(
                color: isToday
                    ? context.colors.primary.withValues(alpha: 0.12)
                    : hasProfit
                        ? (profit! > 0
                            ? upColor.withValues(alpha: 0.08)
                            : downColor.withValues(alpha: 0.08))
                        : Colors.transparent,
                borderRadius: BorderRadius.circular(AppRadius.sm),
                border: isToday
                    ? Border.all(
                        color: context.colors.primary.withValues(alpha: 0.4),
                        width: 1,
                      )
                    : null,
              ),
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Text(
                    '$day',
                    style: AppTextStyles.bodySmall(context).copyWith(
                      fontSize: 10,
                      fontWeight: isToday ? FontWeight.bold : FontWeight.w400,
                      color: isToday
                          ? context.colors.primary
                          : context.colors.onSurface,
                    ),
                  ),
                  if (hasProfit) ...[
                    SizedBox(height: 1),
                    Text(
                      '${profit! > 0 ? '+' : ''}${profit.abs() < 10 ? profit.toStringAsFixed(2) : profit.toStringAsFixed(1)}',
                      style: TextStyle(
                        fontSize: 7,
                        fontWeight: FontWeight.w600,
                        color: profit > 0 ? upColor : downColor,
                      ),
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                    ),
                  ],
                ],
              ),
            ),
          ),
        ),
      );

      if (cells.length == 7) {
        rows.add(Row(children: cells));
        cells = [];
      }
    }

    // 填充月末空白
    if (cells.isNotEmpty) {
      while (cells.length < 7) {
        cells.add(const Expanded(child: SizedBox.shrink()));
      }
      rows.add(Row(children: cells));
    }

    return rows;
  }
}