From 0f65ba7f133a932bb228705c09ef22f495c7576c Mon Sep 17 00:00:00 2001
From: Sergey Krylov <ksv741@mail.ru>
Date: Wed, 4 Nov 2026 14:52:38 +0300
Subject: [PATCH] refactor: move category persistence into bank repository
 (WealthLedger/backend#171)

---
 .../application/expense-categories.service.ts | 67 ++-----------------
 .../infrastructure/bank-cards.repository.ts   | 63 +++++++++++++++++
 2 files changed, 68 insertions(+), 62 deletions(-)

diff --git a/src/modules/banking/bank-cards/application/expense-categories.service.ts b/src/modules/banking/bank-cards/application/expense-categories.service.ts
index 4dbad85..65dadef 100644
--- a/src/modules/banking/bank-cards/application/expense-categories.service.ts
+++ b/src/modules/banking/bank-cards/application/expense-categories.service.ts
@@ -1,81 +1,24 @@
 import { Injectable } from '@nestjs/common';
-import { randomUUID } from 'node:crypto';
 
-import { PrismaService } from '../../../../prisma/prisma.service';
 import { MAX_CATEGORY_NAME_LENGTH } from '../domain/bank-card-limits';
 import { BankCardsRepository } from '../infrastructure/bank-cards.repository';
-import { conflict, missing, name } from './bank-card-input';
-
-const EXPECTED_UPDATED_CATEGORIES = 1;
-const VERSION_INCREMENT = 1;
+import { name } from './bank-card-input';
 
 @Injectable()
 export class ExpenseCategoriesService {
-  constructor(
-    private readonly prisma: PrismaService,
-    private readonly repository: BankCardsRepository,
-  ) {}
+  constructor(private readonly repository: BankCardsRepository) {}
 
   async categories(userId: string) {
-    return (
-      await this.prisma.expenseCategory.findMany({
-        where: { userId },
-        orderBy: [{ name: 'asc' }, { id: 'asc' }],
-      })
-    ).map(({ id, name, seedKey, version }) => ({
-      id,
-      name,
-      isDefault: seedKey === 'other',
-      version,
-    }));
+    return this.repository.categories(userId);
   }
 
   createCategory(userId: string, value: string) {
     const label = name(value, MAX_CATEGORY_NAME_LENGTH);
-    return this.repository.write(async (tx) => {
-      await this.repository.seed(tx, userId);
-      const row = await tx.expenseCategory.create({
-        data: {
-          id: randomUUID(),
-          userId,
-          name: label,
-          nameKey: label.toLocaleLowerCase('ru-RU'),
-        },
-      });
-      return {
-        id: row.id,
-        name: row.name,
-        isDefault: false,
-        version: row.version,
-      };
-    });
+    return this.repository.createCategory(userId, label);
   }
 
   updateCategory(userId: string, id: string, value: string, version: number) {
     const label = name(value, MAX_CATEGORY_NAME_LENGTH);
-    return this.repository.write(async (tx) => {
-      const row = await tx.expenseCategory.findFirst({ where: { id, userId } });
-      if (!row) missing();
-      if (
-        (
-          await tx.expenseCategory.updateMany({
-            where: { id, userId, version },
-            data: {
-              name: label,
-              nameKey: label.toLocaleLowerCase('ru-RU'),
-              version: { increment: 1 },
-            },
-          })
-        ).count !== EXPECTED_UPDATED_CATEGORIES
-      ) {
-        conflict();
-      }
-      return {
-        id,
-        name: label,
-        isDefault: row.seedKey === 'other',
-        version: version + VERSION_INCREMENT,
-      };
-    });
+    return this.repository.updateCategory(userId, id, label, version);
   }
 }
diff --git a/src/modules/banking/bank-cards/infrastructure/bank-cards.repository.ts b/src/modules/banking/bank-cards/infrastructure/bank-cards.repository.ts
index 4f33ba9..488dd68 100644
--- a/src/modules/banking/bank-cards/infrastructure/bank-cards.repository.ts
+++ b/src/modules/banking/bank-cards/infrastructure/bank-cards.repository.ts
@@ -13,6 +13,8 @@ import { BankOperationKind } from '../domain/bank-operation-kind';
 
 const INITIAL_RETRY_COUNT = 0;
 const LAST_SEED_OFFSET = 1;
+const EXPECTED_UPDATED_CATEGORIES = 1;
+const VERSION_INCREMENT = 1;
 
 type Tx = Prisma.TransactionClient;
 const TRANSACTION_MAX_WAIT_MS = 10_000;
@@ -32,6 +34,67 @@ const seeds = [
 @Injectable()
 export class BankCardsRepository {
   constructor(private readonly prisma: PrismaService) {}
+  async categories(userId: string) {
+    return (
+      await this.prisma.expenseCategory.findMany({
+        where: { userId },
+        orderBy: [{ name: 'asc' }, { id: 'asc' }],
+      })
+    ).map(({ id, name, seedKey, version }) => ({
+      id,
+      name,
+      isDefault: seedKey === 'other',
+      version,
+    }));
+  }
+
+  createCategory(userId: string, label: string) {
+    return this.write(async (tx) => {
+      await this.seed(tx, userId);
+      const row = await tx.expenseCategory.create({
+        data: {
+          id: randomUUID(),
+          userId,
+          name: label,
+          nameKey: label.toLocaleLowerCase('ru-RU'),
+        },
+      });
+      return {
+        id: row.id,
+        name: row.name,
+        isDefault: false,
+        version: row.version,
+      };
+    });
+  }
+
+  updateCategory(userId: string, id: string, label: string, version: number) {
+    return this.write(async (tx) => {
+      const row = await tx.expenseCategory.findFirst({ where: { id, userId } });
+      if (!row) missing();
+      if (
+        (
+          await tx.expenseCategory.updateMany({
+            where: { id, userId, version },
+            data: {
+              name: label,
+              nameKey: label.toLocaleLowerCase('ru-RU'),
+              version: { increment: 1 },
+            },
+          })
+        ).count !== EXPECTED_UPDATED_CATEGORIES
+      ) {
+        conflict();
+      }
+      return {
+        id,
+        name: label,
+        isDefault: row.seedKey === 'other',
+        version: version + VERSION_INCREMENT,
+      };
+    });
+  }
+
   async write<T>(run: (tx: Tx) => Promise<T>): Promise<T> {
     for (let attempt = INITIAL_RETRY_COUNT; ; attempt++) {
       try {