feat: [loan] 상품권 접대비 자동 연동 기능 추가

- ExpenseAccount: loan_id 필드 + SUB_TYPE_GIFT_CERTIFICATE 상수 추가
- LoanService: 상품권 used+접대비해당 시 expense_accounts 자동 upsert/삭제
- 마이그레이션: expense_accounts에 loan_id 컬럼 추가

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Models/Tenants/ExpenseAccount.php

@@ -34,6 +34,7 @@ class ExpenseAccount extends Model
         'vendor_name',
         'payment_method',
         'card_no',
+        'loan_id',
         'created_by',
         'updated_by',
         'deleted_by',
@@ -53,6 +54,9 @@ class ExpenseAccount extends Model
 
     public const TYPE_OFFICE = 'office';
 
+    // 세부 유형 상수 (접대비)
+    public const SUB_TYPE_GIFT_CERTIFICATE = 'gift_certificate';
+
     // 세부 유형 상수 (복리후생)
     public const SUB_TYPE_MEAL = 'meal';
 

app/Services/LoanService.php

@@ -2,6 +2,7 @@
 
 namespace App\Services;
 
+use App\Models\Tenants\ExpenseAccount;
 use App\Models\Tenants\Loan;
 use App\Models\Tenants\Withdrawal;
 use Illuminate\Contracts\Pagination\LengthAwarePaginator;
@@ -261,9 +262,56 @@ public function update(int $id, array $data): Loan
 
         $loan->save();
 
+        // 상품권 → 접대비 자동 연동
+        if ($loan->category === Loan::CATEGORY_GIFT_CERTIFICATE) {
+            $this->syncGiftCertificateExpense($loan);
+        }
+
         return $loan->fresh(['user:id,name,email', 'creator:id,name']);
     }
 
+    /**
+     * 상품권 → 접대비 자동 연동
+     *
+     * 상태가 'used' + entertainment_expense='applicable' → expense_accounts에 INSERT
+     * 그 외 → 기존 연결된 expense_accounts 삭제
+     */
+    private function syncGiftCertificateExpense(Loan $loan): void
+    {
+        $metadata = $loan->metadata ?? [];
+        $isEntertainment = ($loan->status === Loan::STATUS_USED)
+            && ($metadata['entertainment_expense'] ?? '') === 'applicable';
+
+        if ($isEntertainment) {
+            // upsert: loan_id 기준으로 있으면 업데이트, 없으면 생성
+            ExpenseAccount::query()
+                ->updateOrCreate(
+                    [
+                        'tenant_id' => $loan->tenant_id,
+                        'loan_id' => $loan->id,
+                    ],
+                    [
+                        'account_type' => ExpenseAccount::TYPE_ENTERTAINMENT,
+                        'sub_type' => ExpenseAccount::SUB_TYPE_GIFT_CERTIFICATE,
+                        'expense_date' => $loan->settlement_date ?? $loan->loan_date,
+                        'amount' => $loan->amount,
+                        'description' => ($metadata['cert_name'] ?? '상품권') . ' 접대비 전환',
+                        'vendor_name' => $metadata['vendor_name'] ?? null,
+                        'vendor_id' => ! empty($metadata['vendor_id']) ? (int) $metadata['vendor_id'] : null,
+                        'payment_method' => ExpenseAccount::PAYMENT_CASH,
+                        'created_by' => $loan->updated_by ?? $loan->created_by,
+                        'updated_by' => $loan->updated_by ?? $loan->created_by,
+                    ]
+                );
+        } else {
+            // 접대비 해당이 아니면 연결된 레코드 삭제
+            ExpenseAccount::query()
+                ->where('tenant_id', $loan->tenant_id)
+                ->where('loan_id', $loan->id)
+                ->delete();
+        }
+    }
+
     /**
      * 가지급금 삭제
      */
@@ -280,6 +328,14 @@ public function destroy(int $id): bool
             throw new BadRequestHttpException(__('error.loan.not_deletable'));
         }
 
+        // 상품권 연결 접대비 레코드도 삭제
+        if ($loan->category === Loan::CATEGORY_GIFT_CERTIFICATE) {
+            ExpenseAccount::query()
+                ->where('tenant_id', $tenantId)
+                ->where('loan_id', $loan->id)
+                ->delete();
+        }
+
         $loan->deleted_by = $userId;
         $loan->save();
         $loan->delete();

database/migrations/2026_03_05_210000_add_loan_id_to_expense_accounts_table.php

@@ -0,0 +1,32 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('expense_accounts', function (Blueprint $table) {
+            $table->unsignedBigInteger('loan_id')->nullable()->after('card_no')
+                ->comment('연결된 가지급금 ID (상품권→접대비 전환 시)');
+
+            $table->index('loan_id');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('expense_accounts', function (Blueprint $table) {
+            $table->dropIndex(['loan_id']);
+            $table->dropColumn('loan_id');
+        });
+    }
+};