feat: link deposits to bill payment

apps/server/src/deposits/deposits.controller.ts

@@ -170,7 +170,7 @@ export class DepositsController {
       action: '退还押金',
       targetId: +id,
       targetType: 'deposit',
-      detail: `退还¥${result.refundAmount}, 扣除¥${result.deductionAmount}`,
+      detail: `退还全部可用押金 ¥${result.refundAmount}`,
       ipAddress,
       userAgent,
     });
@@ -182,7 +182,7 @@ export class DepositsController {
           recipientIds: [student.userId],
           type: 'deposit_refunded',
           title: '押金已退还',
-          content: `您的押金已退还,退还¥${result.refundAmount},扣除¥${result.deductionAmount}`,
+          content: `您的剩余押金已全部退还,金额: ¥${result.refundAmount}`,
         });
       }
     } catch (_) { /* don't block response */ }

apps/server/src/deposits/deposits.service.ts

@@ -46,16 +46,28 @@ export class DepositsService {
   async create(dto: CreateDepositDto, userId?: number) {
     const student = await this.studentRepo.findOne({ where: { id: dto.studentId } });
     if (!student) throw new NotFoundException('学生不存在');
-    const deposit = this.repo.create({
-      studentId: dto.studentId,
-      amount: dto.amount,
-      paidDate: dto.paidDate,
-      notes: dto.notes,
-      status: 'paid',
-      recordedBy: userId,
-    });
+    if (Number(dto.amount) <= 0) throw new BadRequestException('收取金额必须大于0');
 
-    return this.repo.save(deposit);
+    const existing = await this.repo.findOne({ where: { studentId: dto.studentId } });
+    if (existing) {
+      existing.amount = Number((Number(existing.amount || 0) + Number(dto.amount)).toFixed(2));
+      existing.paidDate = dto.paidDate;
+      existing.status = 'paid';
+      existing.recordedBy = userId ?? null;
+      if (dto.notes) existing.notes = dto.notes;
+      return this.repo.save(existing);
+    }
+
+    return this.repo.save(
+      this.repo.create({
+        studentId: dto.studentId,
+        amount: dto.amount,
+        paidDate: dto.paidDate,
+        notes: dto.notes,
+        status: 'paid',
+        recordedBy: userId,
+      }),
+    );
   }
 
   async addInstallment(depositId: number, amount: number, dueDate: string) {
@@ -90,18 +102,16 @@ export class DepositsService {
   async refund(id: number, dto: RefundDepositDto, userId?: number) {
     const deposit = await this.repo.findOne({ where: { id } });
     if (!deposit) throw new NotFoundException('押金记录不存在');
-    if (deposit.status !== 'paid') throw new BadRequestException('该押金已处理');
+    if (deposit.status !== 'paid' || Number(deposit.amount) <= 0) {
+      throw new BadRequestException('该学生当前没有可退押金');
+    }
 
-    const deduction = dto.deductionAmount || 0;
-    const refundAmount = Number(deposit.amount) - deduction;
-    if (refundAmount < 0) throw new BadRequestException('扣除金额不能大于押金金额');
+    const refundAmount = Number(deposit.amount);
 
     deposit.refundDate = dto.refundDate;
-    deposit.deductionAmount = deduction;
-    deposit.deductionReason = dto.deductionReason || '';
     deposit.refundAmount = refundAmount;
-    deposit.status =
-      deduction > 0 ? (refundAmount > 0 ? 'partial_refund' : 'deducted') : 'refunded';
+    deposit.amount = 0;
+    deposit.status = 'refunded';
     if (dto.notes) deposit.notes = dto.notes;
     deposit.refundedBy = userId ?? null;
     deposit.refundedAt = new Date();

apps/server/src/deposits/dto/deposit.dto.ts

@@ -19,14 +19,6 @@ export class RefundDepositDto {
   @IsString()
   refundDate: string;
 
-  @IsOptional()
-  @IsNumber()
-  deductionAmount?: number;
-
-  @IsOptional()
-  @IsString()
-  deductionReason?: string;
-
   @IsOptional()
   @IsString()
   notes?: string;