// RecordService 单测（AC-11）：开始/结束上课状态机、结课单事务联动、幂等、失败整体回滚。
//
// 测试栈：glebarez/sqlite 文件库（真实事务）。分账与课酬用可注入的 fake（断言调用参数与 tx 透传）。
package service

import (
	"context"
	"errors"
	"testing"
	"time"

	"gorm.io/gorm"

	"yuansiwei/unified-backend/internal/academic/apperr"
	"yuansiwei/unified-backend/internal/academic/model"
	"yuansiwei/unified-backend/internal/academic/money"
	"yuansiwei/unified-backend/internal/academic/repository"
	infraerrors "yuansiwei/unified-backend/internal/infra/errors"
)

// dividerCall 一次分账调用记录。
//
// 字段：findUserID 起点用户；stuID 学生；recordID 上课记录；hasTx ctx 中是否带事务（§10.3 红线断言）。
type dividerCall struct {
	findUserID string
	stuID      string
	recordID   int64
	hasTx      bool
}

// fakeDivider 分账入口测试替身（可注入失败，用于验证"整体回滚"）。
type fakeDivider struct {
	calls []dividerCall
	err   error
}

// AddLog 实现 DivideLogGranter。
func (f *fakeDivider) AddLog(ctx context.Context, findUserID, stuID string, recordID int64, _ string) error {
	f.calls = append(f.calls, dividerCall{
		findUserID: findUserID,
		stuID:      stuID,
		recordID:   recordID,
		hasTx:      repository.TxFromContext(ctx) != nil,
	})
	return f.err
}

// fakeQuoter 课酬试算测试替身。
type fakeQuoter struct {
	reward money.Amount
	err    error
	calls  int
}

// QuoteRecordReward 实现 TeacherRewardQuoter。
func (f *fakeQuoter) QuoteRecordReward(_ context.Context, _ RewardQuoteInput) (money.Amount, error) {
	f.calls++
	return f.reward, f.err
}

// learningFixture 结课用例的公共数据（课程 + 2 学生 + 账户 + 一节课）。
type learningFixture struct {
	course   *model.Courses
	record   *model.CoursesRecord
	student1 *model.CoursesStudent // 有推荐人 R1，课费 100.00
	student2 *model.CoursesStudent // 无推荐人，课费 50.00
}

// seedLearningFixture 造结课数据。
//
// 数据口径：S1 lesson_cost=100.00 / 剩余 10 次 / 剩余费用 1000.00，推荐人 R1；
// S2 lesson_cost=50.00 / 剩余 10 次 / 剩余费用 500.00，无推荐人。
func seedLearningFixture(t *testing.T, db *gorm.DB) *learningFixture {
	t.Helper()
	course := seedCourse(t, db, "结课数学", "-1", "1.0", 20)
	start := time.Date(2026, 4, 6, 9, 0, 0, 0, time.Local)
	end := start.Add(time.Hour)
	teacher := "01HTEACHER0000000000001"
	record := &model.CoursesRecord{
		BizNo: "REC-FINISH-1", CoursesID: course.ID, ClassID: 1, TeacherID: &teacher,
		InstitutionID: 1, CampusID: 10, Status: model.CoursesRecordStatusNotStarted,
		StartTime: &start, EndTime: &end,
	}
	if err := db.Create(record).Error; err != nil {
		t.Fatalf("seed 排班实例失败: %v", err)
	}
	recommender := "01HRECOMMENDER000000001"
	s1 := &model.CoursesStudent{
		BizNo: "CS-1", CoursesID: course.ID, ClassID: 1, InstitutionID: 1, CampusID: 10,
		StudentID: "01HSTUDENT0000000000001", Type: model.CoursesStudentTypeNormal,
		Status:     model.CoursesStudentStatusNormal,
		Receivable: "1000.00", NetReceipts: "1000.00", LessonCost: "100.00",
		Number: 10, RemainderNumber: 10, RemainderCost: "1000.00", RemainderReceivable: "0.00",
		RecommenderUserID: &recommender,
	}
	s2 := &model.CoursesStudent{
		BizNo: "CS-2", CoursesID: course.ID, ClassID: 1, InstitutionID: 1, CampusID: 10,
		StudentID: "01HSTUDENT0000000000002", Type: model.CoursesStudentTypeNormal,
		Status:     model.CoursesStudentStatusNormal,
		Receivable: "500.00", NetReceipts: "500.00", LessonCost: "50.00",
		Number: 10, RemainderNumber: 10, RemainderCost: "500.00", RemainderReceivable: "0.00",
	}
	for _, row := range []*model.CoursesStudent{s1, s2} {
		if err := db.Create(row).Error; err != nil {
			t.Fatalf("seed 报课记录(%s) 失败: %v", row.BizNo, err)
		}
		// 资金账户（spend 累加需要账户已建户；全局 + 校区各一行）
		if err := db.Create(&model.UserExpense{UserID: row.StudentID}).Error; err != nil {
			t.Fatalf("seed 全局账户(%s) 失败: %v", row.StudentID, err)
		}
		if err := db.Create(&model.UserExpenseSchool{
			UserID: row.StudentID, InstitutionID: 1, CampusID: 10,
		}).Error; err != nil {
			t.Fatalf("seed 校区账户(%s) 失败: %v", row.StudentID, err)
		}
	}
	return &learningFixture{course: course, record: record, student1: s1, student2: s2}
}

// loadRecord 读排班实例。
func loadRecord(t *testing.T, db *gorm.DB, id int64) model.CoursesRecord {
	t.Helper()
	var row model.CoursesRecord
	if err := db.Where("id = ?", id).First(&row).Error; err != nil {
		t.Fatalf("读取排班实例失败: %v", err)
	}
	return row
}

// loadStudentCourse 读报课记录。
func loadStudentCourse(t *testing.T, db *gorm.DB, id int64) model.CoursesStudent {
	t.Helper()
	var row model.CoursesStudent
	if err := db.Where("id = ?", id).First(&row).Error; err != nil {
		t.Fatalf("读取报课记录失败: %v", err)
	}
	return row
}

// loadSpend 读账户 spend 列（全局 / 校区）。
func loadSpend(t *testing.T, db *gorm.DB, userID string) (global, campus int64) {
	t.Helper()
	var g model.UserExpense
	if err := db.Where("user_id = ?", userID).First(&g).Error; err != nil {
		t.Fatalf("读取全局账户失败: %v", err)
	}
	var s model.UserExpenseSchool
	if err := db.Where("user_id = ? AND campus_id = ?", userID, 10).First(&s).Error; err != nil {
		t.Fatalf("读取校区账户失败: %v", err)
	}
	return cents(t, g.Spend), cents(t, s.Spend)
}

// countRecordStudents 统计某节课的打卡明细行数。
func countRecordStudents(t *testing.T, db *gorm.DB, recordID int64) int64 {
	t.Helper()
	var n int64
	if err := db.Model(&model.CoursesRecordStudent{}).Where("record_id = ?", recordID).Count(&n).Error; err != nil {
		t.Fatalf("统计打卡明细失败: %v", err)
	}
	return n
}

// TestStartRecordStateMachine 开始上课状态机：0→1 成功；重复开始 3121；已结束再开始 3121。
func TestStartRecordStateMachine(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{})
	ctx := context.Background()

	first, err := svc.StartRecord(ctx, fx.record.ID)
	if err != nil {
		t.Fatalf("首次开始上课失败: %v", err)
	}
	if first.Status != model.CoursesRecordStatusOngoing || first.Repeated {
		t.Fatalf("首次开始上课 status=%d repeated=%v，期望 (1,false)", first.Status, first.Repeated)
	}
	rec := loadRecord(t, db, fx.record.ID)
	if rec.ActualStartTime == nil {
		t.Fatal("开始上课后 actual_start_time 应非空")
	}

	// 反向断言：重复开始 → 3121（不是幂等成功：actual_start_time 只写一次）
	_, err = svc.StartRecord(ctx, fx.record.ID)
	requireAppCode(t, err, apperr.CodeRecordStateInvalid)

	// 结束后再开始 → 3121
	if _, ferr := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID}); ferr != nil {
		t.Fatalf("结课失败: %v", ferr)
	}
	_, err = svc.StartRecord(ctx, fx.record.ID)
	requireAppCode(t, err, apperr.CodeRecordStateInvalid)
}

// TestFinishRecordLinkedTransaction 结束上课 = 单事务联动（AC-11 ② 正向断言）。
//
// 断言链（同一事务内的 7 个动作全部生效）：
//  1. record：status=2 + actual_end_time + student_number + income(=Σcost) + teacher_reward；
//  2. record_student：逐学生一行，cost/give_cost/teacher_reward/end_time 落库；
//  3. courses_student：finished_number+1、remainder_number-1、remainder_cost-cost；
//  4. spend：全局 + 校区双写（统计口径，**不动 balance**）；
//  5. 分账：仅"有推荐人且真扣费"的学生触发一次，orderID=recordID，且 ctx 带事务；
//  6. 课酬：按行均分，Σ record_student.teacher_reward == record.teacher_reward。
func TestFinishRecordLinkedTransaction(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	divide := &fakeDivider{}
	quoter := &fakeQuoter{reward: money.FromCents(10000)} // 100.00 一节课
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{Divide: divide, Quoter: quoter})
	ctx := context.Background()

	if _, err := svc.StartRecord(ctx, fx.record.ID); err != nil {
		t.Fatalf("开始上课失败: %v", err)
	}
	out, err := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID})
	if err != nil {
		t.Fatalf("结课失败: %v", err)
	}

	// ① record 汇总
	rec := loadRecord(t, db, fx.record.ID)
	if rec.Status != model.CoursesRecordStatusFinished {
		t.Fatalf("status=%d，期望 2（已结束）", rec.Status)
	}
	if rec.ActualEndTime == nil {
		t.Fatal("actual_end_time 应非空")
	}
	if rec.StudentNumber != 2 {
		t.Fatalf("student_number=%d，期望 2", rec.StudentNumber)
	}
	if got := cents(t, rec.Income); got != 15000 {
		t.Fatalf("income=%d 分，期望 15000（100.00+50.00）", got)
	}
	if got := cents(t, rec.TeacherReward); got != 10000 {
		t.Fatalf("teacher_reward=%d 分，期望 10000", got)
	}
	if out.Repeated {
		t.Fatal("首次结课 Repeated=true，期望 false")
	}

	// ② 打卡明细
	if n := countRecordStudents(t, db, fx.record.ID); n != 2 {
		t.Fatalf("打卡明细=%d 行，期望 2", n)
	}
	var rows []model.CoursesRecordStudent
	if err := db.Where("record_id = ?", fx.record.ID).Order("student_id ASC").Find(&rows).Error; err != nil {
		t.Fatalf("读取打卡明细失败: %v", err)
	}
	rewardSum := int64(0)
	for i := range rows {
		if rows[i].EndTime == nil {
			t.Fatalf("打卡明细(%s) end_time 应非空", rows[i].StudentID)
		}
		rewardSum += cents(t, rows[i].TeacherReward)
	}
	if rewardSum != 10000 {
		t.Fatalf("Σ record_student.teacher_reward=%d 分，期望 10000（= record.teacher_reward）", rewardSum)
	}

	// ③ 扣课时
	s1 := loadStudentCourse(t, db, fx.student1.ID)
	if s1.FinishedNumber != 1 {
		t.Fatalf("S1 finished_number=%d，期望 1", s1.FinishedNumber)
	}
	if s1.RemainderNumber != 9 {
		t.Fatalf("S1 remainder_number=%d，期望 9", s1.RemainderNumber)
	}
	if got := cents(t, s1.RemainderCost); got != 90000 {
		t.Fatalf("S1 remainder_cost=%d 分，期望 90000（1000.00-100.00）", got)
	}
	s2 := loadStudentCourse(t, db, fx.student2.ID)
	if s2.FinishedNumber != 1 || s2.RemainderNumber != 9 {
		t.Fatalf("S2 课次未扣：finished=%d remainder=%d", s2.FinishedNumber, s2.RemainderNumber)
	}
	if got := cents(t, s2.RemainderCost); got != 45000 {
		t.Fatalf("S2 remainder_cost=%d 分，期望 45000（500.00-50.00）", got)
	}

	// ④ spend：全局 + 校区双写，balance 不动
	if g, c := loadSpend(t, db, fx.student1.StudentID); g != 10000 || c != 10000 {
		t.Fatalf("S1 spend 全局/校区=(%d,%d) 分，期望 (10000,10000)", g, c)
	}
	if g, c := loadSpend(t, db, fx.student2.StudentID); g != 5000 || c != 5000 {
		t.Fatalf("S2 spend 全局/校区=(%d,%d) 分，期望 (5000,5000)", g, c)
	}
	var acc model.UserExpense
	if err := db.Where("user_id = ?", fx.student1.StudentID).First(&acc).Error; err != nil {
		t.Fatalf("读取全局账户失败: %v", err)
	}
	if cents(t, acc.Balance) != 0 {
		t.Fatalf("spend 累加不应改 balance，实际 balance=%s", acc.Balance)
	}

	// ⑤ 分账：只有 S1 有推荐人 → 恰好 1 次，orderID=recordID，ctx 带 tx
	if len(divide.calls) != 1 {
		t.Fatalf("分账调用=%d 次，期望 1（仅 S1 有推荐人）", len(divide.calls))
	}
	call := divide.calls[0]
	if call.stuID != fx.student1.StudentID || call.findUserID != "01HRECOMMENDER000000001" || call.recordID != fx.record.ID {
		t.Fatalf("分账入参错误: %+v", call)
	}
	if !call.hasTx {
		t.Fatal("分账调用 ctx 未携带事务（违反 §10.3：事务内跨服务必须 WithTxContext 透传）")
	}
	if quoter.calls != 1 {
		t.Fatalf("课酬试算=%d 次，期望 1（一节课只算一次，再按行均分）", quoter.calls)
	}
}

// TestFinishRecordIdempotent 重复结课 → 幂等成功（不重复扣课时/不重复分账/不新增明细）。
func TestFinishRecordIdempotent(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	divide := &fakeDivider{}
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{Divide: divide})
	ctx := context.Background()

	if _, err := svc.StartRecord(ctx, fx.record.ID); err != nil {
		t.Fatalf("开始上课失败: %v", err)
	}
	if _, err := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID}); err != nil {
		t.Fatalf("首次结课失败: %v", err)
	}
	second, err := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID})
	if err != nil {
		t.Fatalf("重复结课应成功（幂等），实际: %v", err)
	}
	if !second.Repeated {
		t.Fatal("重复结课 Repeated=false，期望 true")
	}
	if second.StudentNumber != 2 || second.Income.Cents() != 15000 {
		t.Fatalf("幂等回读 student_number=%d income=%d，期望 (2,15000)", second.StudentNumber, second.Income.Cents())
	}
	// 反向断言：不重复扣课时、不重复分账、不新增明细
	if s1 := loadStudentCourse(t, db, fx.student1.ID); s1.FinishedNumber != 1 {
		t.Fatalf("重复结课后 S1 finished_number=%d，期望仍为 1", s1.FinishedNumber)
	}
	if n := countRecordStudents(t, db, fx.record.ID); n != 2 {
		t.Fatalf("重复结课后打卡明细=%d 行，期望仍为 2", n)
	}
	if len(divide.calls) != 1 {
		t.Fatalf("重复结课后分账调用=%d 次，期望仍为 1", len(divide.calls))
	}
	if g, _ := loadSpend(t, db, fx.student1.StudentID); g != 10000 {
		t.Fatalf("重复结课后 S1 spend=%d 分，期望仍为 10000", g)
	}
}

// TestFinishRecordRollbackOnDivideFailure 分账失败 → **整笔回滚**（AC-11 ② 反向断言）。
//
// 关键：分账在链路末端（课时已扣、spend 已加、record 已置 2），一旦失败必须全部回滚，
// 否则出现"课时扣了、分成没给"的静默不一致。
func TestFinishRecordRollbackOnDivideFailure(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	boom := errors.New("divide boom")
	divide := &fakeDivider{err: boom}
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{Divide: divide})
	ctx := context.Background()

	if _, err := svc.StartRecord(ctx, fx.record.ID); err != nil {
		t.Fatalf("开始上课失败: %v", err)
	}
	_, err := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID})
	if err == nil {
		t.Fatal("分账失败时结课应返回错误")
	}
	if !errors.Is(err, boom) {
		t.Fatalf("错误应包含底层原因，实际 %v", err)
	}

	rec := loadRecord(t, db, fx.record.ID)
	if rec.Status != model.CoursesRecordStatusOngoing {
		t.Fatalf("回滚后 status=%d，期望 1（仍在上课中）", rec.Status)
	}
	if rec.ActualEndTime != nil {
		t.Fatal("回滚后 actual_end_time 应为空")
	}
	if n := countRecordStudents(t, db, fx.record.ID); n != 0 {
		t.Fatalf("回滚后打卡明细=%d 行，期望 0", n)
	}
	if s1 := loadStudentCourse(t, db, fx.student1.ID); s1.FinishedNumber != 0 {
		t.Fatalf("回滚后 S1 finished_number=%d，期望 0（课时未扣）", s1.FinishedNumber)
	}
	if got := cents(t, loadStudentCourse(t, db, fx.student1.ID).RemainderCost); got != 100000 {
		t.Fatalf("回滚后 S1 remainder_cost=%d 分，期望 100000（未扣）", got)
	}
	if g, c := loadSpend(t, db, fx.student1.StudentID); g != 0 || c != 0 {
		t.Fatalf("回滚后 S1 spend=(%d,%d)，期望 (0,0)", g, c)
	}
}

// TestFinishRecordExplicitAttendance 显式打卡名单：插班生（未报课）可上课但不扣课时。
func TestFinishRecordExplicitAttendance(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{})
	ctx := context.Background()
	if _, err := svc.StartRecord(ctx, fx.record.ID); err != nil {
		t.Fatalf("开始上课失败: %v", err)
	}
	cost := money.FromCents(2000)
	zero := money.Amount(0)
	out, err := svc.FinishRecord(ctx, FinishRecordInput{
		RecordID: fx.record.ID,
		Items: []AttendanceItem{
			{StudentID: "01HSTUDENT0000000000001", Cost: &cost},
			{StudentID: "01HSTUDENT0000000000003", Type: model.CoursesRecordStudentTypeTransfer, Cost: &zero},
		},
	})
	if err != nil {
		t.Fatalf("结课失败: %v", err)
	}
	if out.StudentNumber != 2 || out.Income.Cents() != 2000 {
		t.Fatalf("student_number=%d income=%d，期望 (2,2000)", out.StudentNumber, out.Income.Cents())
	}
	// 插班生（未报课）不扣课时：只有 S1 的 finished_number 变化
	if s1 := loadStudentCourse(t, db, fx.student1.ID); s1.FinishedNumber != 1 {
		t.Fatalf("S1 finished_number=%d，期望 1", s1.FinishedNumber)
	}
	// 未出现在名单里的 S2 不扣课时
	if s2 := loadStudentCourse(t, db, fx.student2.ID); s2.FinishedNumber != 0 {
		t.Fatalf("S2 未上课却被扣课时：finished_number=%d", s2.FinishedNumber)
	}
}

// TestFinishRecordDuplicatedStudentRejected 同一学生在名单里出现两次 → 3140（不静默合并）。
func TestFinishRecordDuplicatedStudentRejected(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{})
	_, err := svc.FinishRecord(context.Background(), FinishRecordInput{
		RecordID: fx.record.ID,
		Items: []AttendanceItem{
			{StudentID: fx.student1.StudentID},
			{StudentID: fx.student1.StudentID},
		},
	})
	requireAppCode(t, err, apperr.CodeBusinessParam)
}

// TestMarkAttendanceUpsertAndGuard 打卡幂等 upsert；已结课不可补打卡（3121）。
func TestMarkAttendanceUpsertAndGuard(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{})
	ctx := context.Background()

	cost := money.FromCents(10000)
	out, err := svc.MarkAttendance(ctx, MarkAttendanceInput{
		RecordID: fx.record.ID,
		Items:    []AttendanceItem{{StudentID: fx.student1.StudentID, Cost: &cost}},
	})
	if err != nil {
		t.Fatalf("打卡失败: %v", err)
	}
	if out.StudentNumber != 1 || out.Income.Cents() != 10000 {
		t.Fatalf("打卡汇总 student_number=%d income=%d，期望 (1,10000)", out.StudentNumber, out.Income.Cents())
	}
	// 重复打卡 → 覆盖同行（不新增）
	cost2 := money.FromCents(12000)
	if _, err := svc.MarkAttendance(ctx, MarkAttendanceInput{
		RecordID: fx.record.ID,
		Items:    []AttendanceItem{{StudentID: fx.student1.StudentID, Cost: &cost2}},
	}); err != nil {
		t.Fatalf("重复打卡失败: %v", err)
	}
	if n := countRecordStudents(t, db, fx.record.ID); n != 1 {
		t.Fatalf("重复打卡后行数=%d，期望 1（按 record+student 幂等）", n)
	}
	// 打卡**不扣课时**（扣课时只发生在结课）
	if s1 := loadStudentCourse(t, db, fx.student1.ID); s1.FinishedNumber != 0 {
		t.Fatalf("打卡不应扣课时，finished_number=%d", s1.FinishedNumber)
	}

	// 结课后补打卡 → 3121
	if _, err := svc.FinishRecord(ctx, FinishRecordInput{RecordID: fx.record.ID}); err != nil {
		t.Fatalf("结课失败: %v", err)
	}
	_, err = svc.MarkAttendance(ctx, MarkAttendanceInput{
		RecordID: fx.record.ID,
		Items:    []AttendanceItem{{StudentID: fx.student2.StudentID, Cost: &cost}},
	})
	requireAppCode(t, err, apperr.CodeRecordStateInvalid)
}

// TestQuoteRewardPlanMissingDoesNotBlock 课酬方案未配置（3112）→ 不阻断结课，课酬记 0.00。
func TestQuoteRewardPlanMissingDoesNotBlock(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	quoter := &fakeQuoter{err: apperr.ErrPayrollPlanMissing}
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{Quoter: quoter})
	out, err := svc.FinishRecord(context.Background(), FinishRecordInput{RecordID: fx.record.ID})
	if err != nil {
		t.Fatalf("3112 不应阻断结课，实际: %v", err)
	}
	if out.TeacherReward.Cents() != 0 {
		t.Fatalf("课酬=%d 分，期望 0", out.TeacherReward.Cents())
	}
	// 反向断言：其他错误必须阻断（整体回滚）
	boom := infraerrors.WithCause(infraerrors.ErrDBError, errors.New("quote db down"))
	db2 := newLearningDB(t)
	fx2 := seedLearningFixture(t, db2)
	svc2 := NewRecordService(db2, campusScope(), RecordServiceOptions{Quoter: &fakeQuoter{err: boom}})
	if _, err := svc2.FinishRecord(context.Background(), FinishRecordInput{RecordID: fx2.record.ID}); err == nil {
		t.Fatal("课酬试算 DB 异常时结课应失败（整体回滚）")
	}
	if n := countRecordStudents(t, db2, fx2.record.ID); n != 0 {
		t.Fatalf("回滚后打卡明细=%d 行，期望 0", n)
	}
}

// TestRecordServiceSingleTransaction 单事务形状：内层失败 → 外层整体回滚（§10.3 单测要求）。
//
// 用一个"分账失败"的注入点验证：若 Repository/下游 service 各自开事务，
// 结课前的扣课时与 spend 会先提交、无法回滚；能全回滚即证明**只开 1 个事务**。
func TestRecordServiceSingleTransaction(t *testing.T) {
	db := newLearningDB(t)
	fx := seedLearningFixture(t, db)
	divide := &fakeDivider{err: errors.New("boom")}
	svc := NewRecordService(db, campusScope(), RecordServiceOptions{Divide: divide})

	_, err := svc.FinishRecord(context.Background(), FinishRecordInput{RecordID: fx.record.ID})
	if err == nil {
		t.Fatal("期望结课失败")
	}
	// 断言"全部无残留"（任何一项非零都说明有过独立提交）
	if n := countRecordStudents(t, db, fx.record.ID); n != 0 {
		t.Fatalf("残留打卡明细 %d 行", n)
	}
	if got := loadRecord(t, db, fx.record.ID); got.Status != model.CoursesRecordStatusNotStarted || got.ActualEndTime != nil {
		t.Fatalf("残留状态 status=%d actual_end=%v", got.Status, got.ActualEndTime)
	}
	if s1 := loadStudentCourse(t, db, fx.student1.ID); s1.FinishedNumber != 0 || cents(t, s1.RemainderCost) != 100000 {
		t.Fatalf("残留课时扣减: finished=%d remainder_cost=%s", s1.FinishedNumber, s1.RemainderCost)
	}
	if g, c := loadSpend(t, db, fx.student1.StudentID); g != 0 || c != 0 {
		t.Fatalf("残留 spend=(%d,%d)", g, c)
	}
	if !divide.calls[0].hasTx {
		t.Fatal("分账调用未携带事务")
	}
}