feat(diary): 手写引擎 + 日记 CRUD + 同步 API (Phase F3 + B2)

Flutter 手写引擎 (Phase F3):
- stroke_model.dart: 笔画数据模型 (StrokePoint/Stroke/BrushType)
- stroke_renderer.dart: perfect_freehand 渲染管线 + 四画笔参数
- handwriting_canvas.dart: Listener 输入 + 掌心抑制 + 去抖过滤
- editor_bloc.dart: BLoC 状态管理 + 撤销/重做 (50步)

Rust 日记 CRUD + 同步 (Phase B2):
- journal_service.rs: CRUD + 软删除 + 分页列表 + 事件发布
- sync_service.rs: 版本号同步 + 冲突检测
- journal_handler.rs: 5个API端点 + utoipa注解 + 权限守卫
- sync_handler.rs: 同步API端点
- error.rs: From<DiaryError> for AppError + 8个单元测试
- 路由注册: /diary/journals + /diary/sync

验证:
- cargo check: 0 error
- cargo test: 433 测试全通过
- flutter analyze: 1 warning (unused private param)

app/lib/features/editor/bloc/editor_bloc.dart

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+// 编辑器 BLoC — 手写状态管理 + 撤销/重做
+
+import 'package:flutter_bloc/flutter_bloc.dart';
+import '../widgets/stroke_model.dart';
+
+// ===== Events =====
+
+abstract class EditorEvent {}
+
+class BrushChanged extends EditorEvent {
+  final BrushType type;
+  final String color;
+  final double width;
+  BrushChanged({required this.type, required this.color, required this.width});
+}
+
+class StrokeCompleted extends EditorEvent {
+  final Stroke stroke;
+  StrokeCompleted(this.stroke);
+}
+
+class Undo extends EditorEvent {}
+
+class Redo extends EditorEvent {}
+
+class ClearCanvas extends EditorEvent {}
+
+class StrokesLoaded extends EditorEvent {
+  final List<Stroke> strokes;
+  StrokesLoaded(this.strokes);
+}
+
+// ===== State =====
+
+class EditorState {
+  final List<Stroke> strokes;
+  final List<Stroke> redoStack;
+  final BrushType brushType;
+  final String brushColor;
+  final double brushWidth;
+  final int maxUndoSteps;
+
+  const EditorState({
+    this.strokes = const [],
+    this.redoStack = const [],
+    this.brushType = BrushType.pen,
+    this.brushColor = '#2D2420',
+    this.brushWidth = 3.0,
+    this.maxUndoSteps = 50,
+  });
+
+  EditorState copyWith({
+    List<Stroke>? strokes,
+    List<Stroke>? redoStack,
+    BrushType? brushType,
+    String? brushColor,
+    double? brushWidth,
+  }) =>
+      EditorState(
+        strokes: strokes ?? this.strokes,
+        redoStack: redoStack ?? this.redoStack,
+        brushType: brushType ?? this.brushType,
+        brushColor: brushColor ?? this.brushColor,
+        brushWidth: brushWidth ?? this.brushWidth,
+        maxUndoSteps: maxUndoSteps,
+      );
+}
+
+// ===== BLoC =====
+
+class EditorBloc extends Bloc<EditorEvent, EditorState> {
+  EditorBloc() : super(const EditorState()) {
+    on<BrushChanged>(_onBrushChanged);
+    on<StrokeCompleted>(_onStrokeCompleted);
+    on<Undo>(_onUndo);
+    on<Redo>(_onRedo);
+    on<ClearCanvas>(_onClearCanvas);
+    on<StrokesLoaded>(_onStrokesLoaded);
+  }
+
+  void _onBrushChanged(BrushChanged event, Emitter<EditorState> emit) {
+    emit(state.copyWith(
+      brushType: event.type,
+      brushColor: event.color,
+      brushWidth: event.width,
+    ));
+  }
+
+  void _onStrokeCompleted(StrokeCompleted event, Emitter<EditorState> emit) {
+    final updatedStrokes = List<Stroke>.from(state.strokes)..add(event.stroke);
+
+    // 超过最大撤销步数时移除最旧的
+    if (updatedStrokes.length > state.maxUndoSteps) {
+      updatedStrokes.removeAt(0);
+    }
+
+    emit(state.copyWith(
+      strokes: updatedStrokes,
+      redoStack: [], // 新笔画清空重做栈
+    ));
+  }
+
+  void _onUndo(Undo event, Emitter<EditorState> emit) {
+    if (state.strokes.isEmpty) return;
+
+    final updatedStrokes = List<Stroke>.from(state.strokes);
+    final lastStroke = updatedStrokes.removeLast();
+    final updatedRedoStack = List<Stroke>.from(state.redoStack)..add(lastStroke);
+
+    emit(state.copyWith(
+      strokes: updatedStrokes,
+      redoStack: updatedRedoStack,
+    ));
+  }
+
+  void _onRedo(Redo event, Emitter<EditorState> emit) {
+    if (state.redoStack.isEmpty) return;
+
+    final updatedRedoStack = List<Stroke>.from(state.redoStack);
+    final stroke = updatedRedoStack.removeLast();
+    final updatedStrokes = List<Stroke>.from(state.strokes)..add(stroke);
+
+    emit(state.copyWith(
+      strokes: updatedStrokes,
+      redoStack: updatedRedoStack,
+    ));
+  }
+
+  void _onClearCanvas(ClearCanvas event, Emitter<EditorState> emit) {
+    emit(state.copyWith(strokes: [], redoStack: []));
+  }
+
+  void _onStrokesLoaded(StrokesLoaded event, Emitter<EditorState> emit) {
+    emit(state.copyWith(strokes: event.strokes, redoStack: []));
+  }
+}

app/lib/features/editor/widgets/handwriting_canvas.dart

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+/// 手写 Canvas 主组件 — 暖记手写引擎的用户交互层。
+///
+/// 核心设计决策：
+/// - 使用 [Listener] 而非 [GestureDetector] 处理指针事件（降低延迟）
+/// - 支持触控笔模式下的掌心抑制（palm rejection）
+/// - 轻量去抖：±1px 移动平均过滤，消除手指微小抖动
+/// - [RepaintBoundary] 隔离重绘范围，避免影响父组件
+///
+/// 性能目标：p99 延迟 < 16ms（满足 60fps 要求）。
+library;
+
+import 'package:flutter/gestures.dart';
+import 'package:flutter/material.dart';
+import 'package:uuid/uuid.dart';
+
+import 'stroke_model.dart';
+import 'stroke_renderer.dart';
+
+// ============================================================
+// 手写 Canvas 组件
+// ============================================================
+
+/// 手写画布，接收用户输入并实时渲染笔画。
+///
+/// 使用方式：
+/// ```dart
+/// HandwritingCanvas(
+///   brushType: BrushType.pen,
+///   brushColor: '#2D2420',
+///   brushWidth: 3.0,
+///   strokes: editorState.strokes,
+///   onStrokeCompleted: (stroke) => context.read<EditorBloc>().add(
+///     StrokeCompleted(stroke),
+///   ),
+/// )
+/// ```
+class HandwritingCanvas extends StatefulWidget {
+  const HandwritingCanvas({
+    super.key,
+    this.brushType = BrushType.pen,
+    this.brushColor = '#2D2420',
+    this.brushWidth = 3.0,
+    this.onStrokeCompleted,
+    this.strokes = const [],
+  });
+
+  /// 当前选中的画笔类型。
+  final BrushType brushType;
+
+  /// 当前画笔颜色（CSS 十六进制格式，如 '#2D2420'）。
+  final String brushColor;
+
+  /// 当前画笔宽度（基准 3.0）。
+  final double brushWidth;
+
+  /// 笔画完成时的回调，将新笔画传递给上层（通常是 BLoC）。
+  final ValueChanged<Stroke>? onStrokeCompleted;
+
+  /// 已有的笔画列表（用于重绘历史内容）。
+  final List<Stroke> strokes;
+
+  @override
+  State<HandwritingCanvas> createState() => _HandwritingCanvasState();
+}
+
+class _HandwritingCanvasState extends State<HandwritingCanvas> {
+  // ============================================================
+  // 状态
+  // ============================================================
+
+  /// 正在绘制中的笔画采样点。
+  List<StrokePoint> _currentPoints = const [];
+
+  /// RepaintBoundary 的 key，用于隔离重绘。
+  final GlobalKey _repaintBoundaryKey = GlobalKey();
+
+  /// UUID 生成器实例。
+  static const _uuid = Uuid();
+
+  // ============================================================
+  // 掌心抑制
+  // ============================================================
+
+  /// 是否启用掌心抑制。
+  ///
+  /// 当设备支持触控笔 (stylus) 时启用：只响应 stylus 输入，
+  /// 忽略触摸 (touch) 输入，防止手掌误触。
+  bool _palmRejectionEnabled = false;
+
+  // ============================================================
+  // 去抖
+  // ============================================================
+
+  /// 上一个有效采样点的坐标（用于去抖计算）。
+  Offset? _lastAcceptedPoint;
+
+  /// 去抖阈值（像素）：移动距离小于此值的点将被过滤。
+  static const double _debounceThreshold = 1.0;
+
+  // ============================================================
+  // 指针事件处理
+  // ============================================================
+
+  /// 指针按下：开始新笔画。
+  ///
+  /// 掌心抑制逻辑：如果已检测到触控笔设备，则只响应 stylus 事件，
+  /// 忽略 touch 事件。首次检测到 stylus 时自动启用抑制。
+  void _onPointerDown(PointerDownEvent event) {
+    // 检测触控笔设备并启用掌心抑制
+    if (event.kind == PointerDeviceKind.stylus) {
+      _palmRejectionEnabled = true;
+    }
+
+    // 掌心抑制：如果已启用且当前非 stylus 输入，忽略
+    if (_palmRejectionEnabled && event.kind != PointerDeviceKind.stylus) {
+      return;
+    }
+
+    // 开始新笔画
+    final point = StrokePoint(
+      x: event.localPosition.dx,
+      y: event.localPosition.dy,
+      pressure: event.pressure,
+      timestamp: DateTime.now().millisecondsSinceEpoch,
+    );
+
+    _currentPoints = [point];
+    _lastAcceptedPoint = Offset(point.x, point.y);
+  }
+
+  /// 指针移动：添加采样点（带去抖过滤）。
+  void _onPointerMove(PointerMoveEvent event) {
+    if (_currentPoints.isEmpty) return;
+
+    // 掌心抑制
+    if (_palmRejectionEnabled && event.kind != PointerDeviceKind.stylus) {
+      return;
+    }
+
+    final candidate = Offset(event.localPosition.dx, event.localPosition.dy);
+
+    // 轻量去抖：移动距离 < 阈值时忽略（消除手指微抖）
+    if (_lastAcceptedPoint != null) {
+      final distance = (candidate - _lastAcceptedPoint!).distance;
+      if (distance < _debounceThreshold) return;
+    }
+
+    final point = StrokePoint(
+      x: candidate.dx,
+      y: candidate.dy,
+      pressure: event.pressure,
+      timestamp: DateTime.now().millisecondsSinceEpoch,
+    );
+
+    setState(() {
+      _currentPoints = [..._currentPoints, point];
+    });
+    _lastAcceptedPoint = candidate;
+  }
+
+  /// 指针抬起：完成笔画并通过回调传递给上层。
+  void _onPointerUp(PointerUpEvent event) {
+    if (_currentPoints.isEmpty) return;
+
+    // 掌心抑制
+    if (_palmRejectionEnabled && event.kind != PointerDeviceKind.stylus) {
+      return;
+    }
+
+    // 至少需要 2 个点才能构成有意义的笔画
+    if (_currentPoints.length < 2) {
+      _currentPoints = const [];
+      _lastAcceptedPoint = null;
+      return;
+    }
+
+    // 创建不可变的 Stroke 对象
+    final stroke = Stroke(
+      id: _uuid.v4(),
+      points: List.unmodifiable(_currentPoints),
+      brushType: widget.brushType,
+      color: widget.brushColor,
+      width: widget.brushWidth,
+    );
+
+    // 通知上层
+    widget.onStrokeCompleted?.call(stroke);
+
+    // 重置当前绘制状态
+    setState(() {
+      _currentPoints = const [];
+      _lastAcceptedPoint = null;
+    });
+  }
+
+  /// 指针取消（如来电打断）：丢弃当前笔画。
+  void _onPointerCancel(PointerCancelEvent event) {
+    setState(() {
+      _currentPoints = const [];
+      _lastAcceptedPoint = null;
+    });
+  }
+
+  // ============================================================
+  // 构建
+  // ============================================================
+
+  @override
+  Widget build(BuildContext context) {
+    // 构造当前正在绘制的笔画（用于实时预览）
+    final currentStroke = _currentPoints.length >= 2
+        ? Stroke(
+            id: '__current__', // 临时 ID，不会被持久化
+            points: _currentPoints,
+            brushType: widget.brushType,
+            color: widget.brushColor,
+            width: widget.brushWidth,
+          )
+        : null;
+
+    return RepaintBoundary(
+      key: _repaintBoundaryKey,
+      child: ClipRect(
+        child: Listener(
+          behavior: HitTestBehavior.opaque,
+          onPointerDown: _onPointerDown,
+          onPointerMove: _onPointerMove,
+          onPointerUp: _onPointerUp,
+          onPointerCancel: _onPointerCancel,
+          child: CustomPaint(
+            painter: StrokePainter(
+              completedStrokes: widget.strokes,
+              currentStroke: currentStroke,
+            ),
+            // 占满父组件可用空间
+            size: Size.infinite,
+          ),
+        ),
+      ),
+    );
+  }
+}

app/lib/features/editor/widgets/stroke_model.dart

@@ -0,0 +1,111 @@
+// 笔画数据模型 — 手写不可变类（避免 build_runner 依赖）
+
+import 'dart:collection';
+
+/// 画笔类型
+enum BrushType {
+  pen('pen'),
+  pencil('pencil'),
+  marker('marker'),
+  eraser('eraser');
+
+  const BrushType(this.value);
+  final String value;
+}
+
+/// 笔画点
+class StrokePoint {
+  const StrokePoint({
+    required this.x,
+    required this.y,
+    this.pressure = 0.5,
+    this.timestamp = 0,
+  });
+
+  final double x;
+  final double y;
+  final double pressure;
+  final int timestamp;
+
+  StrokePoint copyWith({
+    double? x,
+    double? y,
+    double? pressure,
+    int? timestamp,
+  }) =>
+      StrokePoint(
+        x: x ?? this.x,
+        y: y ?? this.y,
+        pressure: pressure ?? this.pressure,
+        timestamp: timestamp ?? this.timestamp,
+      );
+
+  Map<String, dynamic> toJson() => {
+        'x': x,
+        'y': y,
+        'pressure': pressure,
+        'timestamp': timestamp,
+      };
+
+  factory StrokePoint.fromJson(Map<String, dynamic> json) => StrokePoint(
+        x: (json['x'] as num).toDouble(),
+        y: (json['y'] as num).toDouble(),
+        pressure: (json['pressure'] as num?)?.toDouble() ?? 0.5,
+        timestamp: (json['timestamp'] as int?) ?? 0,
+      );
+}
+
+/// 笔画
+class Stroke {
+  const Stroke({
+    required this.id,
+    required this.points,
+    this.brushType = BrushType.pen,
+    this.color = '#2D2420',
+    this.width = 3.0,
+  });
+
+  final String id;
+  final List<StrokePoint> points;
+  final BrushType brushType;
+  final String color;
+  final double width;
+
+  Stroke copyWith({
+    String? id,
+    List<StrokePoint>? points,
+    BrushType? brushType,
+    String? color,
+    double? width,
+  }) =>
+      Stroke(
+        id: id ?? this.id,
+        points: points ?? this.points,
+        brushType: brushType ?? this.brushType,
+        color: color ?? this.color,
+        width: width ?? this.width,
+      );
+
+  Map<String, dynamic> toJson() => {
+        'id': id,
+        'points': points.map((p) => p.toJson()).toList(),
+        'brushType': brushType.value,
+        'color': color,
+        'width': width,
+      };
+
+  factory Stroke.fromJson(Map<String, dynamic> json) => Stroke(
+        id: json['id'] as String,
+        points: UnmodifiableListView(
+          (json['points'] as List)
+              .map((p) => StrokePoint.fromJson(p as Map<String, dynamic>))
+              .toList(),
+        ),
+        brushType: BrushType.values.firstWhere(
+          (b) => b.value == json['brushType'],
+          orElse: () => BrushType.pen,
+        ),
+        color: (json['color'] as String?) ?? '#2D2420',
+        width: (json['width'] as num?)?.toDouble() ?? 3.0,
+      );
+}

app/lib/features/editor/widgets/stroke_renderer.dart

@@ -0,0 +1,235 @@
+// 笔画渲染器 — 将 StrokePoint 列表转换为 Flutter 可绘制路径。
+//
+// 核心流程：
+//   StrokePoint[] → perfect_freehand.getStroke() → Point[] (轮廓多边形)
+//   → buildStrokePath() → Path → CustomPainter.drawPath()
+//
+// 每种画笔（pen/pencil/marker/eraser）拥有独立的 perfect_freehand 参数，
+// 产生不同的视觉效果。
+
+import 'package:flutter/widgets.dart';
+import 'package:perfect_freehand/perfect_freehand.dart' as pf;
+
+import 'stroke_model.dart';
+
+// ============================================================
+// 画笔参数配置
+// ============================================================
+
+/// perfect_freehand 参数集，按画笔类型区分。
+///
+/// 参考设计规格 v1.2：钢笔细致、铅笔柔和、马克笔粗半透明、橡皮擦大范围。
+class _BrushConfig {
+  final double size;
+  final double thinning;
+  final double smoothing;
+  final double streamline;
+  final bool simulatePressure;
+
+  const _BrushConfig({
+    required this.size,
+    required this.thinning,
+    required this.smoothing,
+    this.streamline = 0.5,
+    required this.simulatePressure,
+  });
+}
+
+/// 各画笔的渲染参数。
+const Map<BrushType, _BrushConfig> _brushConfigs = {
+  /// 钢笔：中等粗细，强压感变化，模拟毛笔效果
+  BrushType.pen: _BrushConfig(
+    size: 8,
+    thinning: 0.7,
+    smoothing: 0.5,
+    simulatePressure: true,
+  ),
+
+  /// 铅笔：细线，轻微压感，高平滑度产生自然线条
+  BrushType.pencil: _BrushConfig(
+    size: 4,
+    thinning: 0.3,
+    smoothing: 0.7,
+    simulatePressure: true,
+  ),
+
+  /// 马克笔：粗线，几乎无压感变化，不模拟压力
+  BrushType.marker: _BrushConfig(
+    size: 16,
+    thinning: 0.1,
+    smoothing: 0.5,
+    simulatePressure: false,
+  ),
+
+  /// 橡皮擦：最大范围，无压感变化
+  BrushType.eraser: _BrushConfig(
+    size: 32,
+    thinning: 0,
+    smoothing: 0.5,
+    simulatePressure: false,
+  ),
+};
+
+// ============================================================
+// 点转换工具函数
+// ============================================================
+
+/// 将 [StrokePoint] 列表转换为 perfect_freehand 轮廓点列表。
+///
+/// [brushType] 决定渲染参数，[width] 作为乘数影响最终笔画大小。
+/// 当 [points] 少于 2 个时返回空列表（无法构成笔画）。
+List<Offset> pointsToOutline(
+  List<StrokePoint> points,
+  BrushType brushType,
+  double width,
+) {
+  if (points.length < 2) return const [];
+
+  final config = _brushConfigs[brushType]!;
+  final widthMultiplier = width / 3.0; // 3.0 是默认宽度，缩放到用户选择
+
+  // 转换为 perfect_freehand 的 Point 格式
+  final pfPoints = points
+      .map((p) => pf.Point(p.x, p.y, p.pressure))
+      .toList(growable: false);
+
+  // 调用 getStroke 获取轮廓多边形
+  final outline = pf.getStroke(
+    pfPoints,
+    size: config.size * widthMultiplier,
+    thinning: config.thinning,
+    smoothing: config.smoothing,
+    streamline: config.streamline,
+    simulatePressure: config.simulatePressure,
+    isComplete: true, // 已完成笔画，启用端点处理
+  );
+
+  // 转换为 Flutter Offset
+  return outline.map((p) => Offset(p.x, p.y)).toList(growable: false);
+}
+
+// ============================================================
+// 路径构建
+// ============================================================
+
+/// 将轮廓点列表构建为 Flutter [Path]。
+///
+/// 使用 [Path.addPolygon] 直接构建闭合多边形，
+/// 比 lineTo 逐点连接更高效，且自动闭合。
+Path buildStrokePath(List<Offset> outlinePoints) {
+  if (outlinePoints.isEmpty) return Path();
+
+  final path = Path();
+  path.addPolygon(outlinePoints, true); // true = 自动闭合
+  return path;
+}
+
+// ============================================================
+// 颜色解析工具
+// ============================================================
+
+/// 将 CSS 十六进制颜色字符串 (#RRGGBB) 解析为 Flutter [Color]。
+///
+/// 如果解析失败，回退到默认的深色文字色 #2D2420。
+Color _parseHexColor(String hex) {
+  final hexStr = hex.replaceFirst('#', '');
+  if (hexStr.length != 6) return const Color(0xFF2D2420);
+
+  final value = int.tryParse(hexStr, radix: 16);
+  if (value == null) return const Color(0xFF2D2420);
+
+  return Color(0xFF000000 + value);
+}
+
+// ============================================================
+// 笔画绘制器
+// ============================================================
+
+/// 自定义 [CustomPainter]，负责将所有笔画渲染到 Canvas。
+///
+/// 接收 [completedStrokes]（已完成笔画列表）和可选的 [currentStroke]
+/// （正在绘制中的笔画），分别渲染。
+///
+/// 渲染策略：
+/// - 钢笔/铅笔：正常不透明绘制
+/// - 马克笔：半透明 (0.4 opacity) 模拟荧光笔效果
+/// - 橡皮擦：使用 [BlendMode.dstOut] 擦除底层内容
+class StrokePainter extends CustomPainter {
+  final List<Stroke> completedStrokes;
+  final Stroke? currentStroke;
+
+  StrokePainter({
+    required this.completedStrokes,
+    this.currentStroke,
+  });
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    // 先绘制已完成的笔画
+    for (final stroke in completedStrokes) {
+      _drawStroke(canvas, stroke);
+    }
+
+    // 再绘制正在进行的笔画（覆盖在已完成笔画之上）
+    if (currentStroke != null) {
+      _drawStroke(canvas, currentStroke!);
+    }
+  }
+
+  /// 渲染单条笔画。
+  void _drawStroke(Canvas canvas, Stroke stroke) {
+    final outlinePoints = pointsToOutline(
+      stroke.points,
+      stroke.brushType,
+      stroke.width,
+    );
+    if (outlinePoints.isEmpty) return;
+
+    final path = buildStrokePath(outlinePoints);
+
+    // 根据画笔类型选择不同的绘制策略
+    final paint = _createPaint(stroke);
+    canvas.drawPath(path, paint);
+  }
+
+  /// 根据画笔类型创建对应的 [Paint] 对象。
+  Paint _createPaint(Stroke stroke) {
+    final color = _parseHexColor(stroke.color);
+
+    switch (stroke.brushType) {
+      case BrushType.pen:
+      case BrushType.pencil:
+        // 钢笔和铅笔：不透明实心绘制
+        return Paint()
+          ..color = color
+          ..style = PaintingStyle.fill
+          ..isAntiAlias = true;
+
+      case BrushType.marker:
+        // 马克笔：半透明模拟荧光笔
+        return Paint()
+          ..color = color.withValues(alpha: 0.4)
+          ..style = PaintingStyle.fill
+          ..isAntiAlias = true;
+
+      case BrushType.eraser:
+        // 橡皮擦：使用 dstOut 混合模式擦除底层像素
+        return Paint()
+          ..color = const Color(0xFFFFFFFF) // 颜色无关紧要，blendMode 决定效果
+          ..style = PaintingStyle.fill
+          ..blendMode = BlendMode.dstOut
+          ..isAntiAlias = true;
+    }
+  }
+
+  /// 判断是否需要重绘。
+  ///
+  /// 始终比较引用：当 strokes 列表或 currentStroke 发生变化时重绘。
+  /// 这是最安全的策略，因为笔画数据是不可变的（freezed），
+  /// 引用变化意味着内容一定变化。
+  @override
+  bool shouldRepaint(StrokePainter oldDelegate) {
+    return !identical(completedStrokes, oldDelegate.completedStrokes) ||
+        !identical(currentStroke, oldDelegate.currentStroke);
+  }
+}

crates/erp-diary/src/error.rs

@@ -4,6 +4,8 @@ use axum::http::StatusCode;
 use axum::response::{IntoResponse, Response};
 use serde::Serialize;
 
+use erp_core::error::AppError;
+
 #[derive(Debug, thiserror::Error)]
 pub enum DiaryError {
     #[error("日记未找到: {0}")]
@@ -35,8 +37,37 @@ pub enum DiaryError {
 
     #[error("内部错误: {0}")]
     Internal(String),
+
+    #[error("{0}")]
+    Validation(String),
 }
 
+/// DiaryError -> AppError 转换
+///
+/// Handler 层统一返回 AppError，Service 层统一返回 DiaryError。
+/// 这个 impl 让 Handler 中的 `?` 操作符自动完成转换。
+impl From<DiaryError> for AppError {
+    fn from(err: DiaryError) -> Self {
+        match err {
+            DiaryError::NotFound(msg) => AppError::NotFound(msg),
+            DiaryError::VersionConflict { .. } => AppError::VersionMismatch,
+            DiaryError::InvalidClassCode | DiaryError::ClassCodeExpired => {
+                AppError::Validation(err.to_string())
+            }
+            DiaryError::ClassCodeLocked { .. } => AppError::TooManyRequests,
+            DiaryError::Forbidden => AppError::Forbidden("权限不足".to_string()),
+            DiaryError::ContentSafetyViolation => AppError::Validation(err.to_string()),
+            DiaryError::SyncFailed(_) => AppError::Internal(err.to_string()),
+            DiaryError::BadRequest(msg) => AppError::Validation(msg),
+            DiaryError::Internal(_) => AppError::Internal(err.to_string()),
+            DiaryError::Validation(msg) => AppError::Validation(msg),
+        }
+    }
+}
+
+/// Diary 模块 Result 类型别名
+pub type DiaryResult<T> = Result<T, DiaryError>;
+
 #[derive(Serialize)]
 struct ErrorBody {
     error: String,
@@ -57,6 +88,7 @@ impl IntoResponse for DiaryError {
             DiaryError::SyncFailed(_) => (StatusCode::INTERNAL_SERVER_ERROR, self.to_string()),
             DiaryError::BadRequest(_) => (StatusCode::BAD_REQUEST, self.to_string()),
             DiaryError::Internal(_) => (StatusCode::INTERNAL_SERVER_ERROR, self.to_string()),
+            DiaryError::Validation(_) => (StatusCode::BAD_REQUEST, self.to_string()),
         };
 
         let body = ErrorBody {
@@ -73,3 +105,89 @@ impl From<sea_orm::DbErr> for DiaryError {
         DiaryError::Internal(err.to_string())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use erp_core::error::AppError;
+
+    #[test]
+    fn diary_error_not_found_maps_to_app_not_found() {
+        let app: AppError = DiaryError::NotFound("journal-123".to_string()).into();
+        match app {
+            AppError::NotFound(msg) => assert_eq!(msg, "journal-123"),
+            other => panic!("Expected NotFound, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_version_conflict_maps_to_version_mismatch() {
+        let app: AppError = DiaryError::VersionConflict {
+            local: 1,
+            server: 2,
+        }
+        .into();
+        match app {
+            AppError::VersionMismatch => {}
+            other => panic!("Expected VersionMismatch, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_forbidden_maps_to_app_forbidden() {
+        let app: AppError = DiaryError::Forbidden.into();
+        match app {
+            AppError::Forbidden(_) => {}
+            other => panic!("Expected Forbidden, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_internal_maps_to_app_internal() {
+        let app: AppError = DiaryError::Internal("db error".to_string()).into();
+        match app {
+            AppError::Internal(_) => {}
+            other => panic!("Expected Internal, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_validation_maps_to_app_validation() {
+        let app: AppError = DiaryError::Validation("标题不能为空".to_string()).into();
+        match app {
+            AppError::Validation(msg) => assert_eq!(msg, "标题不能为空"),
+            other => panic!("Expected Validation, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_bad_request_maps_to_app_validation() {
+        let app: AppError = DiaryError::BadRequest("参数错误".to_string()).into();
+        match app {
+            AppError::Validation(msg) => assert_eq!(msg, "参数错误"),
+            other => panic!("Expected Validation, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn diary_error_class_code_locked_maps_to_too_many_requests() {
+        let app: AppError = DiaryError::ClassCodeLocked {
+            lockout_minutes: 30,
+        }
+        .into();
+        match app {
+            AppError::TooManyRequests => {}
+            other => panic!("Expected TooManyRequests, got {:?}", other),
+        }
+    }
+
+    #[test]
+    fn db_err_maps_to_diary_internal() {
+        let err = sea_orm::DbErr::Custom("connection failed".to_string());
+        let diary_err: DiaryError = err.into();
+        match diary_err {
+            DiaryError::Internal(msg) => assert!(msg.contains("connection failed")),
+            other => panic!("Expected Internal, got {:?}", other),
+        }
+    }
+}

crates/erp-diary/src/handler/journal_handler.rs

@@ -0,0 +1,263 @@
+// 日记 API 处理器 — CRUD + 列表
+
+use axum::extract::{Extension, FromRef, Path, Query, State};
+use axum::response::Json;
+use serde::Deserialize;
+use utoipa::IntoParams;
+use uuid::Uuid;
+
+use erp_core::error::AppError;
+use erp_core::rbac::require_permission;
+use erp_core::types::{ApiResponse, PaginatedResponse, TenantContext};
+
+use crate::dto::{CreateJournalReq, JournalResp, UpdateJournalReq};
+use crate::service::journal_service::JournalService;
+use crate::state::DiaryState;
+
+/// 日记列表查询参数
+#[derive(Debug, Deserialize, IntoParams)]
+pub struct JournalListParams {
+    /// 按作者筛选
+    pub author_id: Option<Uuid>,
+    /// 按心情筛选 (happy/calm/sad/angry/thinking)
+    pub mood: Option<String>,
+    /// 日期范围起始
+    pub date_from: Option<chrono::NaiveDate>,
+    /// 日期范围结束
+    pub date_to: Option<chrono::NaiveDate>,
+    /// 按班级筛选
+    pub class_id: Option<Uuid>,
+    /// 页码（默认 1）
+    pub page: Option<u64>,
+    /// 每页条数（默认 20，最大 100）
+    pub page_size: Option<u64>,
+}
+
+#[utoipa::path(
+    post,
+    path = "/api/v1/diary/journals",
+    request_body = CreateJournalReq,
+    responses(
+        (status = 200, description = "创建成功", body = ApiResponse<JournalResp>),
+        (status = 400, description = "验证失败"),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记管理"
+)]
+/// POST /api/v1/diary/journals
+///
+/// 创建日记条目。需要 `diary.journal.create` 权限。
+pub async fn create_journal<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Json(req): Json<CreateJournalReq>,
+) -> Result<Json<ApiResponse<JournalResp>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.create")?;
+
+    // 基础验证
+    if req.title.trim().is_empty() {
+        return Err(AppError::Validation("标题不能为空".to_string()));
+    }
+
+    let resp = JournalService::create(
+        ctx.tenant_id,
+        ctx.user_id,
+        &req,
+        &state.db,
+        &state.event_bus,
+    )
+    .await?;
+
+    Ok(Json(ApiResponse::ok(resp)))
+}
+
+#[utoipa::path(
+    get,
+    path = "/api/v1/diary/journals/{id}",
+    params(("id" = Uuid, Path, description = "日记ID")),
+    responses(
+        (status = 200, description = "成功", body = ApiResponse<JournalResp>),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+        (status = 404, description = "日记不存在"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记管理"
+)]
+/// GET /api/v1/diary/journals/:id
+///
+/// 获取日记详情。需要 `diary.journal.read` 权限。
+pub async fn get_journal<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Path(id): Path<Uuid>,
+) -> Result<Json<ApiResponse<JournalResp>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.read")?;
+
+    let resp = JournalService::get_by_id(ctx.tenant_id, id, &state.db).await?;
+    Ok(Json(ApiResponse::ok(resp)))
+}
+
+#[utoipa::path(
+    put,
+    path = "/api/v1/diary/journals/{id}",
+    params(("id" = Uuid, Path, description = "日记ID")),
+    request_body = UpdateJournalReq,
+    responses(
+        (status = 200, description = "更新成功", body = ApiResponse<JournalResp>),
+        (status = 400, description = "验证失败"),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+        (status = 404, description = "日记不存在"),
+        (status = 409, description = "版本冲突"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记管理"
+)]
+/// PUT /api/v1/diary/journals/:id
+///
+/// 更新日记。需要 `diary.journal.update` 权限。
+/// 请求体中必须包含 `version` 字段用于乐观锁检查。
+pub async fn update_journal<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Path(id): Path<Uuid>,
+    Json(req): Json<UpdateJournalReq>,
+) -> Result<Json<ApiResponse<JournalResp>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.update")?;
+
+    let resp = JournalService::update(
+        ctx.tenant_id,
+        ctx.user_id,
+        id,
+        &req,
+        &state.db,
+        &state.event_bus,
+    )
+    .await?;
+
+    Ok(Json(ApiResponse::ok(resp)))
+}
+
+/// 删除日记请求体（包含版本号）
+#[derive(Debug, Deserialize, utoipa::ToSchema)]
+pub struct DeleteJournalReq {
+    /// 当前版本号（乐观锁）
+    pub version: i32,
+}
+
+#[utoipa::path(
+    delete,
+    path = "/api/v1/diary/journals/{id}",
+    params(("id" = Uuid, Path, description = "日记ID")),
+    request_body = DeleteJournalReq,
+    responses(
+        (status = 200, description = "删除成功"),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+        (status = 404, description = "日记不存在"),
+        (status = 409, description = "版本冲突"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记管理"
+)]
+/// DELETE /api/v1/diary/journals/:id
+///
+/// 软删除日记。需要 `diary.journal.delete` 权限。
+/// 请求体中必须包含 `version` 字段用于乐观锁检查。
+pub async fn delete_journal<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Path(id): Path<Uuid>,
+    Json(req): Json<DeleteJournalReq>,
+) -> Result<Json<ApiResponse<()>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.delete")?;
+
+    JournalService::delete(
+        ctx.tenant_id,
+        ctx.user_id,
+        id,
+        req.version,
+        &state.db,
+        &state.event_bus,
+    )
+    .await?;
+
+    Ok(Json(ApiResponse {
+        success: true,
+        data: None,
+        message: Some("日记已删除".to_string()),
+    }))
+}
+
+#[utoipa::path(
+    get,
+    path = "/api/v1/diary/journals",
+    params(JournalListParams),
+    responses(
+        (status = 200, description = "成功", body = ApiResponse<PaginatedResponse<JournalResp>>),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记管理"
+)]
+/// GET /api/v1/diary/journals
+///
+/// 获取日记列表（分页 + 筛选）。需要 `diary.journal.read` 权限。
+/// 支持按作者、心情、日期范围、班级筛选。
+pub async fn list_journals<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Query(params): Query<JournalListParams>,
+) -> Result<Json<ApiResponse<PaginatedResponse<JournalResp>>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.read")?;
+
+    let page = params.page.unwrap_or(1);
+    let page_size = params.page_size.unwrap_or(20).min(100);
+
+    let (items, total) = JournalService::list(
+        ctx.tenant_id,
+        params.author_id,
+        params.mood,
+        params.date_from,
+        params.date_to,
+        params.class_id,
+        page,
+        page_size,
+        &state.db,
+    )
+    .await?;
+
+    let total_pages = total.div_ceil(page_size);
+
+    Ok(Json(ApiResponse::ok(PaginatedResponse {
+        data: items,
+        total,
+        page,
+        page_size,
+        total_pages,
+    })))
+}

crates/erp-diary/src/handler/mod.rs

@@ -1,2 +1,4 @@
-// erp-diary API 处理器占位
-// 后续 Phase B2-B7 会实现 ~10 个处理器
+// erp-diary API 处理器
+
+pub mod journal_handler;
+pub mod sync_handler;

crates/erp-diary/src/handler/sync_handler.rs

@@ -0,0 +1,53 @@
+// 日记同步 API 处理器
+
+use axum::extract::{Extension, FromRef, State};
+use axum::response::Json;
+
+use erp_core::error::AppError;
+use erp_core::rbac::require_permission;
+use erp_core::types::{ApiResponse, TenantContext};
+
+use crate::dto::SyncReq;
+use crate::dto::SyncResp;
+use crate::service::sync_service::SyncService;
+use crate::state::DiaryState;
+
+#[utoipa::path(
+    post,
+    path = "/api/v1/diary/sync",
+    request_body = SyncReq,
+    responses(
+        (status = 200, description = "同步成功", body = ApiResponse<SyncResp>),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+        (status = 409, description = "存在版本冲突"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "日记同步"
+)]
+/// POST /api/v1/diary/sync
+///
+/// 日记同步端点。客户端提交本地变更，服务端返回服务端变更和冲突列表。
+/// 需要 `diary.journal.read` 权限。
+pub async fn sync_journals<S>(
+    State(state): State<DiaryState>,
+    Extension(ctx): Extension<TenantContext>,
+    Json(req): Json<SyncReq>,
+) -> Result<Json<ApiResponse<SyncResp>>, AppError>
+where
+    DiaryState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "diary.journal.read")?;
+
+    let resp = SyncService::sync(
+        ctx.tenant_id,
+        ctx.user_id,
+        req.last_sync_time,
+        req.changes,
+        &state.db,
+    )
+    .await?;
+
+    Ok(Json(ApiResponse::ok(resp)))
+}

crates/erp-diary/src/lib.rs

@@ -10,6 +10,8 @@ pub use state::DiaryState;
 
 use erp_core::module::ErpModule;
 
+use crate::handler::{journal_handler, sync_handler};
+
 /// 暖记日记业务模块
 pub struct DiaryModule;
 
@@ -108,5 +110,22 @@ impl DiaryModule {
         S: Clone + Send + Sync + 'static,
     {
         axum::Router::new()
+            // 日记 CRUD
+            .route(
+                "/diary/journals",
+                axum::routing::get(journal_handler::list_journals)
+                    .post(journal_handler::create_journal),
+            )
+            .route(
+                "/diary/journals/{id}",
+                axum::routing::get(journal_handler::get_journal)
+                    .put(journal_handler::update_journal)
+                    .delete(journal_handler::delete_journal),
+            )
+            // 日记同步
+            .route(
+                "/diary/sync",
+                axum::routing::post(sync_handler::sync_journals),
+            )
     }
 }

crates/erp-diary/src/service/journal_service.rs

@@ -0,0 +1,306 @@
+// 日记 CRUD 服务
+
+use chrono::Utc;
+use sea_orm::{
+    ActiveModelTrait, ColumnTrait, Condition, DatabaseConnection, EntityTrait, PaginatorTrait,
+    QueryFilter, QueryOrder, Set,
+};
+use uuid::Uuid;
+
+use crate::dto::{CreateJournalReq, JournalResp, UpdateJournalReq};
+use crate::entity::journal_entry;
+use crate::error::{DiaryError, DiaryResult};
+use erp_core::error::check_version;
+use erp_core::events::{DomainEvent, EventBus};
+
+/// 日记 CRUD 服务 — 创建、读取、更新、软删除日记条目
+pub struct JournalService;
+
+impl JournalService {
+    /// 创建日记
+    ///
+    /// 构建包含所有标准字段的 ActiveModel，插入后发布 diary.created 事件。
+    pub async fn create(
+        tenant_id: Uuid,
+        author_id: Uuid,
+        req: &CreateJournalReq,
+        db: &DatabaseConnection,
+        event_bus: &EventBus,
+    ) -> DiaryResult<JournalResp> {
+        let now = Utc::now();
+        let id = Uuid::now_v7();
+
+        let model = journal_entry::ActiveModel {
+            id: Set(id),
+            tenant_id: Set(tenant_id),
+            author_id: Set(author_id),
+            class_id: Set(req.class_id),
+            title: Set(req.title.clone()),
+            date: Set(req.date),
+            mood: Set(serde_json::to_string(&req.mood).unwrap_or_else(|_| "happy".to_string())),
+            weather: Set(
+                serde_json::to_string(&req.weather).unwrap_or_else(|_| "sunny".to_string()),
+            ),
+            tags: Set(Some(serde_json::json!(req.tags))),
+            is_private: Set(req.is_private),
+            shared_to_class: Set(false),
+            assigned_topic_id: Set(req.assigned_topic_id),
+            created_at: Set(now),
+            updated_at: Set(now),
+            created_by: Set(author_id),
+            updated_by: Set(author_id),
+            deleted_at: Set(None),
+            version: Set(1),
+        };
+        let inserted = model.insert(db).await?;
+
+        // 发布领域事件
+        event_bus
+            .publish(
+                DomainEvent::new(
+                    "diary.created",
+                    tenant_id,
+                    serde_json::json!({
+                        "journal_id": id,
+                        "author_id": author_id,
+                        "class_id": req.class_id,
+                    }),
+                ),
+                db,
+            )
+            .await;
+
+        Ok(model_to_resp(inserted))
+    }
+
+    /// 获取日记详情
+    ///
+    /// 按 id + tenant_id + 未删除 查询，找不到返回 NotFound。
+    pub async fn get_by_id(
+        tenant_id: Uuid,
+        id: Uuid,
+        db: &DatabaseConnection,
+    ) -> DiaryResult<JournalResp> {
+        let model = journal_entry::Entity::find()
+            .filter(journal_entry::Column::Id.eq(id))
+            .filter(journal_entry::Column::TenantId.eq(tenant_id))
+            .filter(journal_entry::Column::DeletedAt.is_null())
+            .one(db)
+            .await?
+            .ok_or_else(|| DiaryError::NotFound(format!("日记 {} 不存在", id)))?;
+
+        Ok(model_to_resp(model))
+    }
+
+    /// 更新日记（带版本检查）
+    ///
+    /// 乐观锁：请求中的 version 必须匹配当前数据库记录的 version，
+    /// 否则返回 VersionConflict 错误。
+    pub async fn update(
+        tenant_id: Uuid,
+        operator_id: Uuid,
+        id: Uuid,
+        req: &UpdateJournalReq,
+        db: &DatabaseConnection,
+        event_bus: &EventBus,
+    ) -> DiaryResult<JournalResp> {
+        // 查找现有记录
+        let model = journal_entry::Entity::find()
+            .filter(journal_entry::Column::Id.eq(id))
+            .filter(journal_entry::Column::TenantId.eq(tenant_id))
+            .filter(journal_entry::Column::DeletedAt.is_null())
+            .one(db)
+            .await?
+            .ok_or_else(|| DiaryError::NotFound(format!("日记 {} 不存在", id)))?;
+
+        // 版本检查
+        let new_version = check_version(req.version, model.version)
+            .map_err(|_| DiaryError::VersionConflict {
+                local: req.version,
+                server: model.version,
+            })?;
+
+        let now = Utc::now();
+
+        // 构建更新模型
+        let mut active: journal_entry::ActiveModel = model.into();
+        if let Some(ref title) = req.title {
+            active.title = Set(title.clone());
+        }
+        if let Some(ref mood) = req.mood {
+            active.mood = Set(serde_json::to_string(mood).unwrap_or_else(|_| "happy".to_string()));
+        }
+        if let Some(ref weather) = req.weather {
+            active.weather = Set(
+                serde_json::to_string(weather).unwrap_or_else(|_| "sunny".to_string()),
+            );
+        }
+        if let Some(ref tags) = req.tags {
+            active.tags = Set(Some(serde_json::json!(tags)));
+        }
+        if let Some(is_private) = req.is_private {
+            active.is_private = Set(is_private);
+        }
+        if let Some(shared_to_class) = req.shared_to_class {
+            active.shared_to_class = Set(shared_to_class);
+        }
+        active.updated_at = Set(now);
+        active.updated_by = Set(operator_id);
+        active.version = Set(new_version);
+
+        let updated = active.update(db).await?;
+
+        // 发布领域事件
+        event_bus
+            .publish(
+                DomainEvent::new(
+                    "diary.updated",
+                    tenant_id,
+                    serde_json::json!({
+                        "journal_id": id,
+                        "author_id": operator_id,
+                        "version": new_version,
+                    }),
+                ),
+                db,
+            )
+            .await;
+
+        Ok(model_to_resp(updated))
+    }
+
+    /// 软删除日记
+    ///
+    /// 设置 deleted_at = now, version + 1，发布 diary.deleted 事件。
+    pub async fn delete(
+        tenant_id: Uuid,
+        operator_id: Uuid,
+        id: Uuid,
+        version: i32,
+        db: &DatabaseConnection,
+        event_bus: &EventBus,
+    ) -> DiaryResult<()> {
+        let model = journal_entry::Entity::find()
+            .filter(journal_entry::Column::Id.eq(id))
+            .filter(journal_entry::Column::TenantId.eq(tenant_id))
+            .filter(journal_entry::Column::DeletedAt.is_null())
+            .one(db)
+            .await?
+            .ok_or_else(|| DiaryError::NotFound(format!("日记 {} 不存在", id)))?;
+
+        // 版本检查
+        let new_version = check_version(version, model.version)
+            .map_err(|_| DiaryError::VersionConflict {
+                local: version,
+                server: model.version,
+            })?;
+
+        let now = Utc::now();
+        let mut active: journal_entry::ActiveModel = model.into();
+        active.deleted_at = Set(Some(now));
+        active.updated_at = Set(now);
+        active.updated_by = Set(operator_id);
+        active.version = Set(new_version);
+        active.update(db).await?;
+
+        // 发布领域事件
+        event_bus
+            .publish(
+                DomainEvent::new(
+                    "diary.deleted",
+                    tenant_id,
+                    serde_json::json!({
+                        "journal_id": id,
+                        "author_id": operator_id,
+                    }),
+                ),
+                db,
+            )
+            .await;
+
+        Ok(())
+    }
+
+    /// 日记列表（分页 + 筛选）
+    ///
+    /// 支持按作者、心情、日期范围、班级筛选。
+    /// 返回 (items, total)。
+    pub async fn list(
+        tenant_id: Uuid,
+        author_id: Option<Uuid>,
+        mood: Option<String>,
+        date_from: Option<chrono::NaiveDate>,
+        date_to: Option<chrono::NaiveDate>,
+        class_id: Option<Uuid>,
+        page: u64,
+        page_size: u64,
+        db: &DatabaseConnection,
+    ) -> DiaryResult<(Vec<JournalResp>, u64)> {
+        let mut condition = Condition::all()
+            .add(journal_entry::Column::TenantId.eq(tenant_id))
+            .add(journal_entry::Column::DeletedAt.is_null());
+
+        if let Some(aid) = author_id {
+            condition = condition.add(journal_entry::Column::AuthorId.eq(aid));
+        }
+        if let Some(ref m) = mood {
+            condition = condition.add(journal_entry::Column::Mood.eq(m));
+        }
+        if let Some(from) = date_from {
+            condition = condition.add(journal_entry::Column::Date.gte(from));
+        }
+        if let Some(to) = date_to {
+            condition = condition.add(journal_entry::Column::Date.lte(to));
+        }
+        if let Some(cid) = class_id {
+            condition = condition.add(journal_entry::Column::ClassId.eq(cid));
+        }
+
+        let page_size = page_size.min(100).max(1);
+        let page = page.max(1);
+
+        let paginator = journal_entry::Entity::find()
+            .filter(condition)
+            .order_by_desc(journal_entry::Column::Date)
+            .order_by_desc(journal_entry::Column::CreatedAt)
+            .paginate(db, page_size);
+
+        let total = paginator.num_items().await?;
+
+        let models = paginator
+            .fetch_page(page.saturating_sub(1))
+            .await?;
+
+        let items = models.into_iter().map(model_to_resp).collect();
+
+        Ok((items, total))
+    }
+}
+
+/// Entity Model -> JournalResp DTO 转换
+fn model_to_resp(model: journal_entry::Model) -> JournalResp {
+    use crate::dto::{Mood, Weather};
+
+    let mood: Mood = serde_json::from_str(&model.mood).unwrap_or(Mood::Happy);
+    let weather: Weather = serde_json::from_str(&model.weather).unwrap_or(Weather::Sunny);
+    let tags: Vec<String> = model
+        .tags
+        .and_then(|v| serde_json::from_value(v).ok())
+        .unwrap_or_default();
+
+    JournalResp {
+        id: model.id,
+        author_id: model.author_id,
+        class_id: model.class_id,
+        title: model.title,
+        date: model.date,
+        mood,
+        weather,
+        tags,
+        is_private: model.is_private,
+        shared_to_class: model.shared_to_class,
+        version: model.version,
+        created_at: model.created_at,
+        updated_at: model.updated_at,
+    }
+}

crates/erp-diary/src/service/mod.rs

@@ -1,2 +1,4 @@
-// erp-diary 业务服务占位
-// 后续 Phase B2-B6 会实现 ~12 个服务
+// erp-diary 业务服务
+
+pub mod journal_service;
+pub mod sync_service;

crates/erp-diary/src/service/sync_service.rs

@@ -0,0 +1,236 @@
+// 日记同步服务 — 版本号冲突检测 + 增量同步
+
+use chrono::{DateTime, Utc};
+use sea_orm::{ColumnTrait, Condition, DatabaseConnection, EntityTrait, QueryFilter, Set};
+use uuid::Uuid;
+
+use crate::dto::{ConflictInfo, SyncChange, SyncResp};
+use crate::entity::journal_entry;
+use crate::error::{DiaryError, DiaryResult};
+
+/// 同步服务 — 处理客户端变更上传和服务端变更下发
+pub struct SyncService;
+
+impl SyncService {
+    /// 同步：客户端提交变更，服务端返回服务端变更 + 冲突
+    ///
+    /// 流程：
+    /// 1. 逐条处理客户端变更（create/update/delete）
+    /// 2. 获取 last_sync_time 之后服务端更新的记录
+    /// 3. 检测版本冲突
+    /// 4. 返回 (server_changes, conflicts, sync_time)
+    pub async fn sync(
+        tenant_id: Uuid,
+        user_id: Uuid,
+        last_sync_time: Option<DateTime<Utc>>,
+        client_changes: Vec<SyncChange>,
+        db: &DatabaseConnection,
+    ) -> DiaryResult<SyncResp> {
+        let mut conflicts = Vec::new();
+
+        // 1. 处理客户端变更
+        for change in client_changes {
+            if let Err(e) = Self::apply_client_change(tenant_id, user_id, change, db).await {
+                // 版本冲突收集到冲突列表，其他错误直接返回
+                match e {
+                    DiaryError::VersionConflict {
+                        local,
+                        server,
+                    } => {
+                        conflicts.push(ConflictInfo {
+                            journal_id: Uuid::nil(), // ID 在 apply_client_change 内部处理
+                            local_version: local,
+                            server_version: server,
+                        });
+                    }
+                    _ => return Err(e),
+                }
+            }
+        }
+
+        // 2. 获取服务端变更（last_sync_time 之后更新的）
+        let mut condition = Condition::all()
+            .add(journal_entry::Column::TenantId.eq(tenant_id))
+            .add(journal_entry::Column::AuthorId.eq(user_id));
+
+        if let Some(since) = last_sync_time {
+            condition = condition.add(journal_entry::Column::UpdatedAt.gt(since));
+        }
+
+        let server_records = journal_entry::Entity::find()
+            .filter(condition)
+            .all(db)
+            .await?;
+
+        // 3. 转换为 JSON 格式的服务端变更
+        let server_changes: Vec<serde_json::Value> = server_records
+            .iter()
+            .map(|r| {
+                serde_json::json!({
+                    "id": r.id,
+                    "title": r.title,
+                    "date": r.date,
+                    "mood": r.mood,
+                    "weather": r.weather,
+                    "tags": r.tags,
+                    "is_private": r.is_private,
+                    "shared_to_class": r.shared_to_class,
+                    "version": r.version,
+                    "updated_at": r.updated_at,
+                    "deleted_at": r.deleted_at,
+                })
+            })
+            .collect();
+
+        // 4. 返回同步结果
+        Ok(SyncResp {
+            server_changes,
+            conflicts,
+            sync_time: Utc::now(),
+        })
+    }
+
+    /// 处理单条客户端变更
+    async fn apply_client_change(
+        tenant_id: Uuid,
+        user_id: Uuid,
+        change: SyncChange,
+        db: &DatabaseConnection,
+    ) -> DiaryResult<()> {
+        use sea_orm::ActiveModelTrait;
+
+        match change {
+            SyncChange::CreateJournal { data } => {
+                // 客户端创建 — 直接插入
+                let id = data
+                    .get("id")
+                    .and_then(|v| v.as_str())
+                    .and_then(|s| Uuid::parse_str(s).ok())
+                    .unwrap_or_else(Uuid::now_v7);
+
+                let title = data
+                    .get("title")
+                    .and_then(|v| v.as_str())
+                    .unwrap_or("")
+                    .to_string();
+
+                let now = Utc::now();
+                let model = journal_entry::ActiveModel {
+                    id: Set(id),
+                    tenant_id: Set(tenant_id),
+                    author_id: Set(user_id),
+                    class_id: Set(None),
+                    title: Set(title),
+                    date: Set(
+                        data.get("date")
+                            .and_then(|v| v.as_str())
+                            .and_then(|s| s.parse().ok())
+                            .unwrap_or_else(|| now.date_naive()),
+                    ),
+                    mood: Set(
+                        data.get("mood")
+                            .and_then(|v| v.as_str())
+                            .unwrap_or("happy")
+                            .to_string(),
+                    ),
+                    weather: Set(
+                        data.get("weather")
+                            .and_then(|v| v.as_str())
+                            .unwrap_or("sunny")
+                            .to_string(),
+                    ),
+                    tags: Set(data.get("tags").cloned()),
+                    is_private: Set(
+                        data.get("is_private")
+                            .and_then(|v| v.as_bool())
+                            .unwrap_or(true),
+                    ),
+                    shared_to_class: Set(false),
+                    assigned_topic_id: Set(None),
+                    created_at: Set(now),
+                    updated_at: Set(now),
+                    created_by: Set(user_id),
+                    updated_by: Set(user_id),
+                    deleted_at: Set(None),
+                    version: Set(1),
+                };
+                model.insert(db).await?;
+            }
+            SyncChange::UpdateJournal {
+                id,
+                version,
+                data,
+            } => {
+                // 客户端更新 — 带版本检查
+                let existing = journal_entry::Entity::find()
+                    .filter(journal_entry::Column::Id.eq(id))
+                    .filter(journal_entry::Column::TenantId.eq(tenant_id))
+                    .filter(journal_entry::Column::DeletedAt.is_null())
+                    .one(db)
+                    .await?
+                    .ok_or_else(|| DiaryError::NotFound(format!("日记 {} 不存在", id)))?;
+
+                if existing.version != version {
+                    return Err(DiaryError::VersionConflict {
+                        local: version,
+                        server: existing.version,
+                    });
+                }
+
+                let now = Utc::now();
+                let mut active: journal_entry::ActiveModel = existing.into();
+
+                if let Some(title) = data.get("title").and_then(|v| v.as_str()) {
+                    active.title = Set(title.to_string());
+                }
+                if let Some(mood) = data.get("mood").and_then(|v| v.as_str()) {
+                    active.mood = Set(mood.to_string());
+                }
+                if let Some(weather) = data.get("weather").and_then(|v| v.as_str()) {
+                    active.weather = Set(weather.to_string());
+                }
+                if let Some(tags) = data.get("tags").cloned() {
+                    active.tags = Set(Some(tags));
+                }
+                if let Some(is_private) = data.get("is_private").and_then(|v| v.as_bool()) {
+                    active.is_private = Set(is_private);
+                }
+                if let Some(shared) = data.get("shared_to_class").and_then(|v| v.as_bool()) {
+                    active.shared_to_class = Set(shared);
+                }
+
+                active.updated_at = Set(now);
+                active.updated_by = Set(user_id);
+                active.version = Set(version + 1);
+                active.update(db).await?;
+            }
+            SyncChange::DeleteJournal { id, version } => {
+                // 客户端删除 — 软删除带版本检查
+                let existing = journal_entry::Entity::find()
+                    .filter(journal_entry::Column::Id.eq(id))
+                    .filter(journal_entry::Column::TenantId.eq(tenant_id))
+                    .filter(journal_entry::Column::DeletedAt.is_null())
+                    .one(db)
+                    .await?
+                    .ok_or_else(|| DiaryError::NotFound(format!("日记 {} 不存在", id)))?;
+
+                if existing.version != version {
+                    return Err(DiaryError::VersionConflict {
+                        local: version,
+                        server: existing.version,
+                    });
+                }
+
+                let now = Utc::now();
+                let mut active: journal_entry::ActiveModel = existing.into();
+                active.deleted_at = Set(Some(now));
+                active.updated_at = Set(now);
+                active.updated_by = Set(user_id);
+                active.version = Set(version + 1);
+                active.update(db).await?;
+            }
+        }
+
+        Ok(())
+    }
+}