[CLAUDE] Workflow: LeaveBalance business logic — trừ phép khi duyệt + số dư (Phase 11 P11-B)

Số dư phép theo (User × LeaveType × Year) + trừ tự động khi đơn nghỉ duyệt cuối.
Policy: cho phép vượt số dư (âm) + cảnh báo (anh main chốt), tích hợp vào trang đơn nghỉ.

Schema (Mig 42 AddLeaveBalances — pure additive, 1 bảng):
- LeaveBalance: UserId + LeaveTypeId + Year + EntitledDays + UsedDays + AdjustmentDays.
  UNIQUE (UserId,LeaveTypeId,Year), FK LeaveType Restrict, decimal(5,2).
  Remaining = Entitled + Adjustment − Used (computed, không store).

Deduction hook (ApproveLeaveRequestHandler nhánh terminal DaDuyet — exactly-once):
- Upsert LeaveBalance(RequesterUserId, LeaveTypeId, StartDate.Year), auto-create từ
  LeaveType.DaysPerYear, UsedDays += NumDays. Guard Status!=DaGuiDuyet chặn re-approve.

FK invariant guard (em main thêm sau test reveal FK risk):
- Create + UpdateDraft validate LeaveTypeId tồn tại (AnyAsync) → ConflictException.
  Đóng cửa vào — bogus type không thể tới deduction FK insert (tránh 500 kẹt đơn).

CQRS LeaveBalanceFeatures.cs: GetMy (self, lazy merge active LeaveType) + GetUser (admin)
  + AdjustLeaveBalance (admin upsert carry-over). Controller [Authorize] + admin Roles=Admin.
Embed: GetLeaveRequestByIdHandler trả balance NGƯỜI TẠO (approver xem thấy đúng).
FE: WorkflowAppDetailPage ×2 — block "Số dư phép" + cảnh báo vượt khi kind=leave (SHA256 identical).

Tests (+11, 130→154 PASS): deduction single/multi-level/accumulate/negative-allowed/
  reject-return-no-deduct + lazy-merge + adjust upsert + Create guard bogus→Conflict.
  Cũng repair 2 test S42 terminal FK-fail (template BuildLeave +seed LeaveType).

Verify: build 0 error · 154 test · FE ×2 · reviewer Max PASS (deduction exactly-once +
  FK invariant fully closed, 2 minor concurrency/comment defer).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.claude/agent-memory/test-specialist/MEMORY.md

@@ -15,9 +15,12 @@ WRITE specialist độc quyền `tests/**`. xUnit + FluentAssertions 7.2 + EF SQ
 - ❌ NOT: production code `src/Backend/**` + `fe-*/**` → test reveal bug → REPORT em main, KHÔNG fix
 - ❌ NOT: decide WHAT to test (test plan) → em main + reviewer chốt priority
 
-## 📊 Baseline 141 PASS (58 Domain + 83 Infra)  ← S42 +11 WorkflowApp ApproveV2
+## 📊 Baseline 152 PASS (58 Domain + 94 Infra)  ← S43 +8 LeaveBalance + repaired 2 template terminal FK-fail
 Run: `dotnet test SolutionErp.slnx --nologo --verbosity minimal`
 
+### ⚠️ Pattern: deduction hook FK → seed LeaveType cho terminal test (S43)
+LeaveBalance → LeaveType `Restrict` FK. ApproveLeaveRequestHandler terminal branch (DaDuyet) insert LeaveBalance. Test đi tới DaDuyet PHẢI seed 1 LeaveType row + LeaveRequest.LeaveTypeId = type.Id (KHÔNG random Guid → FK fail SQLite Error 19). Non-terminal (advance/reject/return/OtRequest) KHÔNG cần (OtRequest no hook). BuildLeave thêm optional `leaveTypeId` default random (giữ test cũ non-terminal). Year = StartDate.Year. Negative allowed (no quota guard → Remaining<0 OK). Query lazy synth Entitled=DaysPerYear khi 0 row.
+
 ## ⏱️ Timing rules (docs/rules.md §7)
 - Feature mới = test-after (UAT ổn → viết, Phase 9 skip per `feedback_uat_skip_verify`)
 - Bug fix = test-before BẮT BUỘC (reproduce → fix)
@@ -49,9 +52,9 @@ Test theo CODE (single source truth), document mismatch header comment + report.
 
 ## 📅 Recent activity (last 10 FIFO)
 
-- **2026-05-29 (S39 agent split setup):** NEW dedicated agent. Seeded test patterns (10 reflection authz + 11 infra helper + 12 InternalsVisibleTo + #48 SQLite tie-break + spec drift S34). Inherited coverage gap backlog 4 priority items từ S36 Reviewer audit (130 PASS baseline). First spawn pending em main S39+ test bundle task (recommend Gap 1 Holiday composite UNIQUE first).
 - **2026-05-29 (S40 baseline audit smoke):** CONFIRMED 130 PASS (Domain 58 + Infra 72), 0 fail/skip, ~15s. Runner count authoritative; raw `[Fact]/[Theory]` attr = 48+70 (Theory→InlineData expand). Infra spread 15 files. Gap re-verified vs prod: EmployeesController+HrmConfigsController EXIST, authz regression chỉ ApprovalWorkflowsV2Controller (gotcha #44 gap real). Proposal = Domain entity + EF config only, CHƯA có ApproveV2Async service (S37 skeleton, defer đúng). Agent load OK. AUDIT-only, no write.
 - **2026-05-30 (S42 P11-A Wave4):** +11 test `tests/.../Application/WorkflowAppApproveV2Tests.cs` → **141 PASS** (Infra 72→83). LeaveRequest 8 case full (Submit happy/guard×2, Approve advance/terminal/UPSERT-invariant/forbidden/empty-comment-placeholder, Reject→TuChoi, Return→TraLai+RejectedFromStatus) + OtRequest smoke (submit→approve single-level→DaDuyet). **No prod bug** — LeaveOt ApproveV2 wire correct, all PASS first run. **NEW Pattern:** WorkflowApps handlers = CQRS MediatR (KHÔNG service) → instantiate handler trực tiếp `new ApproveLeaveRequestHandler(db, AsUser(u), clock).Handle(cmd,ct)`, chỉ 3 dep (IApplicationDbContext + TestCurrentUser + FixedDateTime) — nhẹ hơn 6-dep Contract service. MaDonTu format "DT/LR/2026/001". Gap #4 (Workflow Apps) PARTIAL done — Travel/Vehicle mirror pending. ⚠️ Lesson: CWD drift (fe-user) → ghi MEMORY nhầm path, em main relocate. Verify CWD root trước Write memory.
+- **2026-05-30 (S43 P11-B Wave3 LeaveBalance):** +8 test `tests/.../Application/LeaveBalanceTests.cs` → **152 PASS** (Infra 86→94). Deduction hook (ApproveLeaveRequestHandler terminal) full: deduct single-level (create row from DaysPerYear), only-at-terminal multi-level (advance no-deduct + 1× terminal), accumulate UPSERT (5+2=7 no new row), negative allowed (Used20>Entitled12 → Remaining−8 no throw), Reject+Return no-deduct (split 5a/5b), GetMyLeaveBalances lazy synth (2 active type filter inactive), AdjustLeaveBalance upsert. **⚠️ FOUND + FIXED 2 pre-existing RED** in S42 template (`Approve_LastLevel_TransitionsToDaDuyet` + `Approve_EmptyComment_StoresPlaceholder`): Wave 1 deduction hook (uncommitted, prod) làm terminal insert LeaveBalance FK→LeaveTypes Restrict FAIL vì BuildLeave dùng `LeaveTypeId=Guid.NewGuid()`. **NOT prod bug** (prod đơn luôn pin LeaveType thật) — fix tại test: BuildLeave +optional leaveTypeId, seed LeaveType ở 2 test đó. Baseline thật trước S43 = 142-pass/2-RED (KHÔNG phải 144-green). REPORTED em main.
 
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