import 'package:flutter/material.dart';
import '../models/record.dart';
import '../services/database_service.dart';
import '../widgets/statistics/view_selector.dart';
import '../widgets/statistics/monthly_overview.dart';
import '../widgets/statistics/daily_chart.dart';
import '../widgets/statistics/category_chart.dart';
import '../widgets/statistics/daily_report.dart';

class StatisticsPage extends StatefulWidget {
  const StatisticsPage({Key? key}) : super(key: key);

  @override
  State<StatisticsPage> createState() => _StatisticsPageState();
}

class _StatisticsPageState extends State<StatisticsPage> {
  final _dbService = DatabaseService();
  bool _isMonthView = true;  // true为月视图，false为年视图
  DateTime _selectedDate = DateTime.now();
  List<Record> _records = [];

  @override
  void initState() {
    super.initState();
    _loadRecords();
  }

  /// 加载记录数据
  Future<void> _loadRecords() async {
    DateTime startDate;
    DateTime endDate;

    if (_isMonthView) {
      startDate = DateTime(_selectedDate.year, _selectedDate.month, 1);
      endDate = DateTime(_selectedDate.year, _selectedDate.month + 1, 0, 23, 59, 59);
    } else {
      startDate = DateTime(_selectedDate.year, 1, 1);
      endDate = DateTime(_selectedDate.year, 12, 31, 23, 59, 59);
    }

    final records = await _dbService.getRecordsByDateRange(startDate, endDate);
    setState(() => _records = records);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('统计'),
      ),
      body: Column(
        children: [
          // 视图选择器
          ViewSelector(
            isMonthView: _isMonthView,
            selectedDate: _selectedDate,
            onViewChanged: (isMonth) {
              setState(() {
                _isMonthView = isMonth;
                _loadRecords();
              });
            },
            onDateChanged: (date) {
              setState(() {
                _selectedDate = date;
                _loadRecords();
              });
            },
          ),
          // 数据详情
          Expanded(
            child: _isMonthView ? _buildMonthView() : _buildYearView(),
          ),
        ],
      ),
    );
  }

  /// 构建月视图
  Widget _buildMonthView() {
    if (_records.isEmpty) {
      return const Center(
        child: Text('暂无数据'),
      );
    }

    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        children: [
          // 月度总览
          MonthlyOverview(records: _records),
          const SizedBox(height: 16),
          // 每日统计图表
          if (_hasValidRecords) ...[
            DailyChart(records: _records),
            const SizedBox(height: 16),
          ],
          // 分类统计图表
          if (_hasValidRecords) ...[
            CategoryChart(records: _records),
            const SizedBox(height: 16),
          ],
          // 日报表
          if (_hasValidRecords)
            DailyReport(records: _records),
        ],
      ),
    );
  }

  /// 构建年视图
  Widget _buildYearView() {
    return const Center(
      child: Text('年度统计功能开发中...'),
    );
  }

  /// 检查是否有有效记录
  bool get _hasValidRecords => _records.isNotEmpty;
}