feat(wakatime_screen): 增加日期范围选择功能并显示每日编码时间图表(#5)

- 添加日期范围选择器，支持今天、近三天和近一周的快速选择
- 实现开始日期和结束日期的单独选择功能
- 新增每日编码时间图表，展示所选日期范围内的编码时间分布
- 优化界面布局，提升用户体验

lib/screens/wakatime_screen.dart

@@ -24,6 +24,9 @@ class _WakatimeScreenState extends State<WakatimeScreen>
   String? _touchedChartType;
   late AnimationController _animationController;
   late Animation<double> _animation;
+  DateTime _selectedStartDate = DateTime.now();
+  DateTime _selectedEndDate = DateTime.now();
+  int? _touchedDayIndex;
 
   // 预定义的颜色列表
   final List<Color> _colors = [
@@ -54,14 +57,19 @@ class _WakatimeScreenState extends State<WakatimeScreen>
     );
     _animationController.forward();
 
-    // 设置默认日期为今天和一周前
+    // 设置默认日期为今天
     final now = DateTime.now();
-    _startDateController.text =
+    _selectedStartDate = now;
-        _formatDate(now.subtract(const Duration(days: 7)));
+    _selectedEndDate = now;
-    _endDateController.text = _formatDate(now);
+    _updateDateControllers();
     _fetchData();
   }
 
+  void _updateDateControllers() {
+    _startDateController.text = _formatDate(_selectedStartDate);
+    _endDateController.text = _formatDate(_selectedEndDate);
+  }
+
   String _formatDate(DateTime date) {
     return '${date.year}-${date.month.toString().padLeft(2, '0')}-${date.day.toString().padLeft(2, '0')}';
   }
@@ -72,6 +80,26 @@ class _WakatimeScreenState extends State<WakatimeScreen>
     return '${hours}小时${minutes}分钟';
   }
 
+  void _selectDateRange(String range) {
+    final now = DateTime.now();
+    switch (range) {
+      case 'today':
+        _selectedStartDate = now;
+        _selectedEndDate = now;
+        break;
+      case '3days':
+        _selectedStartDate = now.subtract(const Duration(days: 2));
+        _selectedEndDate = now;
+        break;
+      case 'week':
+        _selectedStartDate = now.subtract(const Duration(days: 6));
+        _selectedEndDate = now;
+        break;
+    }
+    _updateDateControllers();
+    _fetchData();
+  }
+
   Future<void> _fetchData() async {
     final authService = Provider.of<AuthService>(context, listen: false);
     final token = authService.credentials['wakatime_token'];
@@ -328,6 +356,237 @@ class _WakatimeScreenState extends State<WakatimeScreen>
     );
   }
 
+  Widget _buildDateRangeSelector() {
+    return Column(
+      children: [
+        Row(
+          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+          children: [
+            _buildDateRangeButton('今天', 'today'),
+            _buildDateRangeButton('近三天', '3days'),
+            _buildDateRangeButton('近一周', 'week'),
+          ],
+        ),
+        const SizedBox(height: 16),
+        Row(
+          children: [
+            Expanded(
+              child: TextField(
+                controller: _startDateController,
+                readOnly: true,
+                decoration: const InputDecoration(
+                  labelText: '开始日期',
+                  hintText: 'YYYY-MM-DD',
+                  suffixIcon: Icon(Icons.calendar_today),
+                ),
+                onTap: () async {
+                  final DateTime? picked = await showDatePicker(
+                    context: context,
+                    initialDate: _selectedStartDate,
+                    firstDate:
+                        DateTime.now().subtract(const Duration(days: 365)),
+                    lastDate: DateTime.now(),
+                  );
+                  if (picked != null) {
+                    setState(() {
+                      _selectedStartDate = picked;
+                      if (picked.isAfter(_selectedEndDate)) {
+                        _selectedEndDate = picked;
+                        _endDateController.text = _formatDate(picked);
+                      }
+                      _startDateController.text = _formatDate(picked);
+                      _fetchData();
+                    });
+                  }
+                },
+              ),
+            ),
+            const SizedBox(width: 16),
+            Expanded(
+              child: TextField(
+                controller: _endDateController,
+                readOnly: true,
+                decoration: const InputDecoration(
+                  labelText: '结束日期',
+                  hintText: 'YYYY-MM-DD',
+                  suffixIcon: Icon(Icons.calendar_today),
+                ),
+                onTap: () async {
+                  final DateTime? picked = await showDatePicker(
+                    context: context,
+                    initialDate: _selectedEndDate,
+                    firstDate: _selectedStartDate,
+                    lastDate: DateTime.now(),
+                  );
+                  if (picked != null) {
+                    setState(() {
+                      _selectedEndDate = picked;
+                      if (picked.isBefore(_selectedStartDate)) {
+                        _selectedStartDate = picked;
+                        _startDateController.text = _formatDate(picked);
+                      }
+                      _endDateController.text = _formatDate(picked);
+                      _fetchData();
+                    });
+                  }
+                },
+              ),
+            ),
+          ],
+        ),
+      ],
+    );
+  }
+
+  Widget _buildDateRangeButton(String text, String range) {
+    final isSelected =
+        (range == 'today' && _selectedStartDate == _selectedEndDate) ||
+            (range == '3days' &&
+                _selectedEndDate.difference(_selectedStartDate).inDays == 2) ||
+            (range == 'week' &&
+                _selectedEndDate.difference(_selectedStartDate).inDays == 6);
+
+    return ElevatedButton(
+      onPressed: () => _selectDateRange(range),
+      style: ElevatedButton.styleFrom(
+        backgroundColor: isSelected ? Theme.of(context).primaryColor : null,
+        foregroundColor: isSelected ? Colors.white : null,
+      ),
+      child: Text(text),
+    );
+  }
+
+  Widget _buildDailyChart() {
+    if (_summary == null || _summary!.data.length <= 1)
+      return const SizedBox.shrink();
+
+    final dailyData = _summary!.data;
+    final maxSeconds = dailyData
+        .map((d) => d.grandTotal.totalSeconds)
+        .reduce((a, b) => a > b ? a : b);
+
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        const Text(
+          '每日编码时间',
+          style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
+        ),
+        const SizedBox(height: 16),
+        SizedBox(
+          height: 200,
+          child: BarChart(
+            BarChartData(
+              alignment: BarChartAlignment.spaceAround,
+              maxY: maxSeconds.toDouble(),
+              barTouchData: BarTouchData(
+                touchCallback: (FlTouchEvent event, response) {
+                  if (event.isInterestedForInteractions &&
+                      response != null &&
+                      response.spot != null) {
+                    setState(() {
+                      _touchedDayIndex = response.spot!.touchedBarGroupIndex;
+                    });
+                  } else {
+                    setState(() {
+                      _touchedDayIndex = null;
+                    });
+                  }
+                },
+                handleBuiltInTouches: false,
+                touchTooltipData: BarTouchTooltipData(
+                  tooltipBgColor: Colors.blueGrey,
+                  getTooltipItem: (group, groupIndex, rod, rodIndex) {
+                    final date =
+                        DateTime.parse(dailyData[groupIndex].range.date);
+                    final seconds = rod.toY.toInt();
+                    return BarTooltipItem(
+                      '${_formatDate(date)}\n${_formatDuration(seconds)}',
+                      const TextStyle(
+                        color: Colors.white,
+                        fontWeight: FontWeight.bold,
+                      ),
+                    );
+                  },
+                ),
+              ),
+              titlesData: FlTitlesData(
+                show: true,
+                topTitles: const AxisTitles(
+                  sideTitles: SideTitles(showTitles: false),
+                ),
+                leftTitles: const AxisTitles(
+                  sideTitles: SideTitles(showTitles: false),
+                ),
+                bottomTitles: AxisTitles(
+                  sideTitles: SideTitles(
+                    showTitles: true,
+                    getTitlesWidget: (value, meta) {
+                      if (value >= 0 && value < dailyData.length) {
+                        final date =
+                            DateTime.parse(dailyData[value.toInt()].range.date);
+                        return Padding(
+                          padding: const EdgeInsets.only(top: 8.0),
+                          child: Text(
+                            '${date.month}/${date.day}',
+                            style: const TextStyle(fontSize: 10),
+                          ),
+                        );
+                      }
+                      return const Text('');
+                    },
+                  ),
+                ),
+                rightTitles: AxisTitles(
+                  sideTitles: SideTitles(
+                    showTitles: true,
+                    getTitlesWidget: (value, meta) {
+                      return Text(
+                        '${(value / 3600).round()}h',
+                        style: const TextStyle(fontSize: 10),
+                      );
+                    },
+                  ),
+                ),
+              ),
+              borderData: FlBorderData(show: false),
+              gridData: FlGridData(show: false),
+              barGroups: dailyData.asMap().entries.map((entry) {
+                final index = entry.key;
+                final day = entry.value;
+                final isTouched = index == _touchedDayIndex;
+                return BarChartGroupData(
+                  x: index,
+                  barRods: [
+                    BarChartRodData(
+                      toY: day.grandTotal.totalSeconds.toDouble(),
+                      width: 20,
+                      color: isTouched
+                          ? Theme.of(context).primaryColor
+                          : Theme.of(context).primaryColor.withOpacity(0.5),
+                    ),
+                  ],
+                );
+              }).toList(),
+            ),
+          ),
+        ),
+        if (_touchedDayIndex != null) ...[
+          const SizedBox(height: 16),
+          Center(
+            child: Text(
+              '${_formatDate(DateTime.parse(dailyData[_touchedDayIndex!].range.date))}: ${_formatDuration(dailyData[_touchedDayIndex!].grandTotal.totalSeconds.toInt())}',
+              style: const TextStyle(
+                fontSize: 16,
+                fontWeight: FontWeight.bold,
+              ),
+            ),
+          ),
+        ],
+      ],
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -339,30 +598,7 @@ class _WakatimeScreenState extends State<WakatimeScreen>
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
-            // 日期选择
+            _buildDateRangeSelector(),
-            Row(
-              children: [
-                Expanded(
-                  child: TextField(
-                    controller: _startDateController,
-                    decoration: const InputDecoration(
-                      labelText: '开始日期',
-                      hintText: 'YYYY-MM-DD',
-                    ),
-                  ),
-                ),
-                const SizedBox(width: 16),
-                Expanded(
-                  child: TextField(
-                    controller: _endDateController,
-                    decoration: const InputDecoration(
-                      labelText: '结束日期',
-                      hintText: 'YYYY-MM-DD',
-                    ),
-                  ),
-                ),
-              ],
-            ),
             const SizedBox(height: 16),
 
             // 获取数据按钮
@@ -388,6 +624,10 @@ class _WakatimeScreenState extends State<WakatimeScreen>
               _buildTotalTime(),
               const SizedBox(height: 24),
 
+              // 每日编码时间图表
+              _buildDailyChart(),
+              const SizedBox(height: 24),
+
               // 项目时间分布
               _buildProjectList(),
               const SizedBox(height: 24),