feat(saving-goals): add saving goals and contribution management

.agents/memory.md

@@ -23,6 +23,10 @@ File này chỉ lưu sự thật và quyết định dài hạn giúp các phiê
   `CUSTOM`, `WEEKLY`, `MONTHLY`, `YEARLY` và archive để giữ lịch sử. Mức sử dụng,
   phần trăm cùng cảnh báo ngưỡng được tổng hợp trực tiếp từ Transaction `EXPENSE`
   trong khoảng thời gian `[startDate, endDate)` khi đọc API.
+- Saving Goal có trạng thái `ACTIVE`, `PAUSED`, `COMPLETED`, dùng archive để giữ lịch sử
+  và tổng hợp tiến độ từ Saving Contribution. Trạng thái hoàn thành được đồng bộ tự
+  động trong transaction Serializable khi contribution hoặc số tiền mục tiêu thay đổi;
+  contribution không tự động thay đổi số dư Wallet.
 
 ## Trạng thái đã biết
 
@@ -37,7 +41,9 @@ File này chỉ lưu sự thật và quyết định dài hạn giúp các phiê
   `20260728190000_add_category_management` đồng bộ thay đổi của Wallet và Category;
   `20260728210000_add_transaction_management` đồng bộ Decimal, receipt/location và index
   của Transaction; `20260729100000_add_budget_management` đồng bộ Decimal, loại,
-  chu kỳ, ngưỡng cảnh báo, archive và index của Budget.
+  chu kỳ, ngưỡng cảnh báo, archive và index của Budget;
+  `20260731100000_add_saving_goals_management` thêm Saving Goal, Saving Contribution,
+  lifecycle, constraint và index phục vụ theo dõi tiến độ.
   Migration history cũ vẫn chưa phản ánh đầy đủ các thay đổi schema của auth đã
   được commit trước đó.
 

prisma/migrations/20260731100000_add_saving_goals_management/migration.sql

+-- Add saving goals and their contribution history.
+CREATE TYPE "SavingGoalStatus" AS ENUM ('ACTIVE', 'PAUSED', 'COMPLETED');
+
+CREATE TABLE "saving_goals" (
+  "id" UUID NOT NULL,
+  "user_id" UUID NOT NULL,
+  "name" TEXT NOT NULL,
+  "target_amount" DECIMAL(18, 2) NOT NULL,
+  "currency" VARCHAR(3) NOT NULL DEFAULT 'VND',
+  "target_date" TIMESTAMP(3) NOT NULL,
+  "description" TEXT,
+  "icon" TEXT,
+  "color" TEXT,
+  "status" "SavingGoalStatus" NOT NULL DEFAULT 'ACTIVE',
+  "completed_at" TIMESTAMP(3),
+  "is_archived" BOOLEAN NOT NULL DEFAULT false,
+  "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  "updated_at" TIMESTAMP(3) NOT NULL,
+
+  CONSTRAINT "saving_goals_pkey" PRIMARY KEY ("id"),
+  CONSTRAINT "saving_goals_target_amount_positive_check"
+    CHECK ("target_amount" > 0),
+  CONSTRAINT "saving_goals_currency_format_check"
+    CHECK ("currency" ~ '^[A-Z]{3}$'),
+  CONSTRAINT "saving_goals_completion_check"
+    CHECK (
+      ("status" = 'COMPLETED' AND "completed_at" IS NOT NULL)
+      OR ("status" <> 'COMPLETED' AND "completed_at" IS NULL)
+    )
+);
+
+CREATE TABLE "saving_contributions" (
+  "id" UUID NOT NULL,
+  "saving_goal_id" UUID NOT NULL,
+  "amount" DECIMAL(18, 2) NOT NULL,
+  "contributed_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  "note" TEXT,
+  "created_at" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  "updated_at" TIMESTAMP(3) NOT NULL,
+
+  CONSTRAINT "saving_contributions_pkey" PRIMARY KEY ("id"),
+  CONSTRAINT "saving_contributions_amount_positive_check"
+    CHECK ("amount" > 0)
+);
+
+CREATE INDEX "saving_goals_user_id_is_archived_idx"
+ON "saving_goals"("user_id", "is_archived");
+
+CREATE INDEX "saving_goals_user_id_status_idx"
+ON "saving_goals"("user_id", "status");
+
+CREATE INDEX "saving_goals_user_id_target_date_idx"
+ON "saving_goals"("user_id", "target_date");
+
+CREATE INDEX "saving_contributions_saving_goal_id_contributed_at_idx"
+ON "saving_contributions"("saving_goal_id", "contributed_at");
+
+ALTER TABLE "saving_goals"
+ADD CONSTRAINT "saving_goals_user_id_fkey"
+FOREIGN KEY ("user_id") REFERENCES "users"("id")
+ON DELETE CASCADE ON UPDATE CASCADE;
+
+ALTER TABLE "saving_contributions"
+ADD CONSTRAINT "saving_contributions_saving_goal_id_fkey"
+FOREIGN KEY ("saving_goal_id") REFERENCES "saving_goals"("id")
+ON DELETE CASCADE ON UPDATE CASCADE;

prisma/schema.prisma

@@ -24,6 +24,12 @@ enum BudgetPeriod {
   YEARLY
 }
 
+enum SavingGoalStatus {
+  ACTIVE
+  PAUSED
+  COMPLETED
+}
+
 model User {
   id          String    @id @default(uuid()) @db.Uuid
   email       String?   @unique
@@ -44,6 +50,7 @@ model User {
   categories          Category[]
   transactions        Transaction[]
   budgets             Budget[]
+  savingGoals         SavingGoal[]
   refreshTokens       RefreshToken[]
   socialAccounts      UserSocial[]
   verificationTokens  VerificationToken[]
@@ -164,6 +171,46 @@ model Budget {
   @@map("budgets")
 }
 
+model SavingGoal {
+  id           String           @id @default(uuid()) @db.Uuid
+  userId       String           @map("user_id") @db.Uuid
+  name         String
+  targetAmount Decimal          @map("target_amount") @db.Decimal(18, 2)
+  currency     String           @default("VND") @db.VarChar(3)
+  targetDate   DateTime         @map("target_date")
+  description  String?
+  icon         String?
+  color        String?
+  status       SavingGoalStatus @default(ACTIVE)
+  completedAt  DateTime?        @map("completed_at")
+  isArchived   Boolean          @default(false) @map("is_archived")
+  createdAt    DateTime         @default(now()) @map("created_at")
+  updatedAt    DateTime         @updatedAt @map("updated_at")
+
+  user          User                 @relation(fields: [userId], references: [id], onDelete: Cascade)
+  contributions SavingContribution[]
+
+  @@index([userId, isArchived])
+  @@index([userId, status])
+  @@index([userId, targetDate])
+  @@map("saving_goals")
+}
+
+model SavingContribution {
+  id            String   @id @default(uuid()) @db.Uuid
+  savingGoalId  String   @map("saving_goal_id") @db.Uuid
+  amount        Decimal  @db.Decimal(18, 2)
+  contributedAt DateTime @default(now()) @map("contributed_at")
+  note          String?
+  createdAt     DateTime @default(now()) @map("created_at")
+  updatedAt     DateTime @updatedAt @map("updated_at")
+
+  savingGoal SavingGoal @relation(fields: [savingGoalId], references: [id], onDelete: Cascade)
+
+  @@index([savingGoalId, contributedAt])
+  @@map("saving_contributions")
+}
+
 model RefreshToken {
   id        String   @id @default(uuid()) @db.Uuid
   token     String   @unique

src/common/errors/error-code.ts

@@ -19,6 +19,10 @@ export const ERROR_CODE = {
   TRANSACTION_CATEGORY_TYPE_MISMATCH: 'TRANSACTION_CATEGORY_TYPE_MISMATCH',
   BUDGET_ARCHIVED: 'BUDGET_ARCHIVED',
   BUDGET_CATEGORY_TYPE_INVALID: 'BUDGET_CATEGORY_TYPE_INVALID',
+  SAVING_GOAL_ARCHIVED: 'SAVING_GOAL_ARCHIVED',
+  SAVING_GOAL_PAUSED: 'SAVING_GOAL_PAUSED',
+  SAVING_GOAL_COMPLETED: 'SAVING_GOAL_COMPLETED',
+  SAVING_GOAL_CURRENCY_LOCKED: 'SAVING_GOAL_CURRENCY_LOCKED',
   FILE_TYPE_UNSUPPORTED: 'FILE_TYPE_UNSUPPORTED',
   FILE_TOO_LARGE: 'FILE_TOO_LARGE',
   RECEIPT_NOT_FOUND: 'RECEIPT_NOT_FOUND',

src/config/swagger.config.ts

@@ -14,7 +14,7 @@ export const swaggerSpec = {
   info: {
     title: 'FinWise API',
     version: '1.0.0',
-    description: 'Backend API cho FinWise - Sổ tay Chi tiêu & Báo cáo Tài chính (Zalo Mini App). API cung cấp xác thực, quản lý người dùng, ví, danh mục, giao dịch và ngân sách.',
+    description: 'Backend API cho FinWise - Sổ tay Chi tiêu & Báo cáo Tài chính (Zalo Mini App). API cung cấp xác thực, quản lý người dùng, ví, danh mục, giao dịch, ngân sách và mục tiêu tiết kiệm.',
     contact: { name: 'FinWise Team' },
   },
   servers: [
@@ -640,6 +640,224 @@ export const swaggerSpec = {
           },
         ],
       },
+      SavingGoalProgress: {
+        type: 'object',
+        required: [
+          'savedAmount',
+          'remainingAmount',
+          'progressPercentage',
+          'contributionCount',
+          'daysRemaining',
+          'isOverdue',
+        ],
+        properties: {
+          savedAmount: {
+            type: 'string',
+            pattern: '^\\d+(\\.\\d{2})$',
+            example: '5000000.00',
+          },
+          remainingAmount: {
+            type: 'string',
+            pattern: '^\\d+(\\.\\d{2})$',
+            example: '15000000.00',
+          },
+          progressPercentage: {
+            type: 'string',
+            pattern: '^\\d+(\\.\\d{2})$',
+            example: '25.00',
+            description: 'May exceed 100 when contributions exceed the target.',
+          },
+          contributionCount: { type: 'integer', example: 5 },
+          lastContributionAt: {
+            type: 'string',
+            format: 'date-time',
+            nullable: true,
+          },
+          daysRemaining: {
+            type: 'integer',
+            minimum: 0,
+            description: 'Whole calendar-day estimate, clamped to zero.',
+          },
+          isOverdue: { type: 'boolean' },
+        },
+      },
+      SavingGoal: {
+        type: 'object',
+        required: [
+          'id',
+          'name',
+          'targetAmount',
+          'currency',
+          'targetDate',
+          'status',
+          'isArchived',
+          'createdAt',
+          'updatedAt',
+          'progress',
+        ],
+        properties: {
+          id: { type: 'string', format: 'uuid' },
+          name: { type: 'string', example: 'Buy a laptop' },
+          targetAmount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+            example: '20000000.00',
+          },
+          currency: { type: 'string', pattern: '^[A-Z]{3}$', example: 'VND' },
+          targetDate: { type: 'string', format: 'date-time' },
+          description: { type: 'string', nullable: true },
+          icon: { type: 'string', nullable: true },
+          color: { type: 'string', nullable: true, example: '#2563EB' },
+          status: {
+            type: 'string',
+            enum: ['ACTIVE', 'PAUSED', 'COMPLETED'],
+            description: 'COMPLETED is managed automatically from contribution totals.',
+          },
+          completedAt: {
+            type: 'string',
+            format: 'date-time',
+            nullable: true,
+          },
+          isArchived: { type: 'boolean' },
+          createdAt: { type: 'string', format: 'date-time' },
+          updatedAt: { type: 'string', format: 'date-time' },
+          progress: { $ref: '#/components/schemas/SavingGoalProgress' },
+        },
+      },
+      CreateSavingGoalBody: {
+        type: 'object',
+        required: ['name', 'targetAmount', 'targetDate'],
+        properties: {
+          name: { type: 'string', minLength: 1, maxLength: 100 },
+          targetAmount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+            example: '20000000.00',
+          },
+          currency: {
+            type: 'string',
+            pattern: '^[A-Za-z]{3}$',
+            default: 'VND',
+          },
+          targetDate: {
+            type: 'string',
+            format: 'date-time',
+            description: 'Must be in the future.',
+          },
+          description: { type: 'string', nullable: true, maxLength: 500 },
+          icon: { type: 'string', nullable: true, maxLength: 100 },
+          color: {
+            type: 'string',
+            nullable: true,
+            pattern: '^#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})$',
+          },
+        },
+      },
+      UpdateSavingGoalBody: {
+        type: 'object',
+        minProperties: 1,
+        properties: {
+          name: { type: 'string', minLength: 1, maxLength: 100 },
+          targetAmount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+          },
+          currency: { type: 'string', pattern: '^[A-Za-z]{3}$' },
+          targetDate: {
+            type: 'string',
+            format: 'date-time',
+            description: 'Must be in the future.',
+          },
+          description: { type: 'string', nullable: true, maxLength: 500 },
+          icon: { type: 'string', nullable: true, maxLength: 100 },
+          color: {
+            type: 'string',
+            nullable: true,
+            pattern: '^#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})$',
+          },
+          status: {
+            type: 'string',
+            enum: ['ACTIVE', 'PAUSED'],
+            description: 'Clients cannot set COMPLETED directly.',
+          },
+        },
+      },
+      SavingContribution: {
+        type: 'object',
+        required: [
+          'id',
+          'savingGoalId',
+          'amount',
+          'contributedAt',
+          'createdAt',
+          'updatedAt',
+        ],
+        properties: {
+          id: { type: 'string', format: 'uuid' },
+          savingGoalId: { type: 'string', format: 'uuid' },
+          amount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+            example: '1000000.00',
+          },
+          contributedAt: { type: 'string', format: 'date-time' },
+          note: { type: 'string', nullable: true, maxLength: 500 },
+          createdAt: { type: 'string', format: 'date-time' },
+          updatedAt: { type: 'string', format: 'date-time' },
+        },
+      },
+      CreateSavingContributionBody: {
+        type: 'object',
+        required: ['amount'],
+        properties: {
+          amount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+            example: '1000000.00',
+          },
+          contributedAt: {
+            type: 'string',
+            format: 'date-time',
+            description: 'Defaults to now and cannot be in the future.',
+          },
+          note: { type: 'string', nullable: true, maxLength: 500 },
+        },
+      },
+      UpdateSavingContributionBody: {
+        type: 'object',
+        minProperties: 1,
+        properties: {
+          amount: {
+            type: 'string',
+            pattern: '^(?:0|[1-9]\\d{0,15})(?:\\.\\d{1,2})?$',
+          },
+          contributedAt: {
+            type: 'string',
+            format: 'date-time',
+            description: 'Cannot be in the future.',
+          },
+          note: { type: 'string', nullable: true, maxLength: 500 },
+        },
+      },
+      SavingGoalResponse: {
+        allOf: [
+          { $ref: '#/components/schemas/SuccessResponse' },
+          {
+            type: 'object',
+            properties: {
+              data: { $ref: '#/components/schemas/SavingGoal' },
+            },
+          },
+        ],
+      },
+      SavingContributionMutation: {
+        type: 'object',
+        required: ['contribution', 'goal'],
+        properties: {
+          contribution: { $ref: '#/components/schemas/SavingContribution' },
+          goal: { $ref: '#/components/schemas/SavingGoal' },
+        },
+      },
     },
     parameters: {
       PageParam: { in: 'query', name: 'page', schema: { type: 'integer', default: 1 } },
@@ -673,6 +891,20 @@ export const swaggerSpec = {
         schema: { type: 'string', format: 'uuid' },
         description: 'Budget ID',
       },
+      SavingGoalIdParam: {
+        in: 'path',
+        name: 'id',
+        required: true,
+        schema: { type: 'string', format: 'uuid' },
+        description: 'Saving goal ID',
+      },
+      SavingContributionIdParam: {
+        in: 'path',
+        name: 'contributionId',
+        required: true,
+        schema: { type: 'string', format: 'uuid' },
+        description: 'Saving contribution ID',
+      },
     },
     responses: {
       Unauthorized: { description: 'Chưa đăng nhập', content: { 'application/json': { schema: { $ref: '#/components/schemas/ErrorResponse' } } } },
@@ -699,6 +931,10 @@ export const swaggerSpec = {
       name: 'Budgets',
       description: 'Authenticated budget limits, real-time usage, and threshold alerts',
     },
+    {
+      name: 'Saving Goals',
+      description: 'Authenticated saving goals, progress, and contribution history',
+    },
   ],
   paths: {
     '/health': {
@@ -2215,5 +2451,402 @@ export const swaggerSpec = {
         },
       },
     },
+    '/saving-goals': {
+      get: {
+        tags: ['Saving Goals'],
+        summary: 'List saving goals with contribution progress',
+        security: [{ BearerAuth: [] }],
+        parameters: [
+          {
+            in: 'query',
+            name: 'search',
+            schema: { type: 'string', minLength: 1, maxLength: 200 },
+          },
+          {
+            in: 'query',
+            name: 'status',
+            schema: {
+              type: 'string',
+              enum: ['ACTIVE', 'PAUSED', 'COMPLETED'],
+            },
+          },
+          {
+            in: 'query',
+            name: 'dueFrom',
+            schema: { type: 'string', format: 'date-time' },
+          },
+          {
+            in: 'query',
+            name: 'dueTo',
+            schema: { type: 'string', format: 'date-time' },
+          },
+          {
+            in: 'query',
+            name: 'includeArchived',
+            schema: { type: 'string', enum: ['true', 'false'], default: 'false' },
+          },
+          {
+            in: 'query',
+            name: 'sortBy',
+            schema: {
+              type: 'string',
+              enum: [
+                'name',
+                'targetAmount',
+                'targetDate',
+                'createdAt',
+                'updatedAt',
+              ],
+              default: 'targetDate',
+            },
+          },
+          {
+            in: 'query',
+            name: 'order',
+            schema: { type: 'string', enum: ['asc', 'desc'], default: 'asc' },
+          },
+          { $ref: '#/components/parameters/PageParam' },
+          { $ref: '#/components/parameters/LimitParam' },
+        ],
+        responses: {
+          200: {
+            description: 'Paginated saving goals with aggregated progress',
+            content: {
+              'application/json': {
+                schema: {
+                  allOf: [
+                    { $ref: '#/components/schemas/SuccessResponse' },
+                    {
+                      type: 'object',
+                      properties: {
+                        data: {
+                          type: 'array',
+                          items: { $ref: '#/components/schemas/SavingGoal' },
+                        },
+                        meta: { $ref: '#/components/schemas/PaginationMeta' },
+                      },
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+      post: {
+        tags: ['Saving Goals'],
+        summary: 'Create a saving goal',
+        description: 'Creates an ACTIVE goal. Contributions are tracked separately and do not change wallet balances.',
+        security: [{ BearerAuth: [] }],
+        requestBody: {
+          required: true,
+          content: {
+            'application/json': {
+              schema: { $ref: '#/components/schemas/CreateSavingGoalBody' },
+            },
+          },
+        },
+        responses: {
+          201: {
+            description: 'Saving goal created',
+            content: {
+              'application/json': {
+                schema: { $ref: '#/components/schemas/SavingGoalResponse' },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+    },
+    '/saving-goals/{id}': {
+      get: {
+        tags: ['Saving Goals'],
+        summary: 'Get a saving goal with progress',
+        security: [{ BearerAuth: [] }],
+        parameters: [{ $ref: '#/components/parameters/SavingGoalIdParam' }],
+        responses: {
+          200: {
+            description: 'Saving goal details',
+            content: {
+              'application/json': {
+                schema: { $ref: '#/components/schemas/SavingGoalResponse' },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+      put: {
+        tags: ['Saving Goals'],
+        summary: 'Update a saving goal',
+        description: 'Archived goals are read-only. COMPLETED is derived from total contributions; clients may only pause or resume a goal. Currency is locked after the first contribution.',
+        security: [{ BearerAuth: [] }],
+        parameters: [{ $ref: '#/components/parameters/SavingGoalIdParam' }],
+        requestBody: {
+          required: true,
+          content: {
+            'application/json': {
+              schema: { $ref: '#/components/schemas/UpdateSavingGoalBody' },
+            },
+          },
+        },
+        responses: {
+          200: {
+            description: 'Saving goal updated',
+            content: {
+              'application/json': {
+                schema: { $ref: '#/components/schemas/SavingGoalResponse' },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          409: { $ref: '#/components/responses/Conflict' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+      delete: {
+        tags: ['Saving Goals'],
+        summary: 'Archive a saving goal',
+        description: 'Keeps the goal and all contribution history for reporting.',
+        security: [{ BearerAuth: [] }],
+        parameters: [{ $ref: '#/components/parameters/SavingGoalIdParam' }],
+        responses: {
+          200: {
+            description: 'Saving goal archived',
+            content: {
+              'application/json': {
+                schema: { $ref: '#/components/schemas/SavingGoalResponse' },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+    },
+    '/saving-goals/{id}/restore': {
+      patch: {
+        tags: ['Saving Goals'],
+        summary: 'Restore an archived saving goal',
+        description: 'Recalculates completion status from the preserved contributions.',
+        security: [{ BearerAuth: [] }],
+        parameters: [{ $ref: '#/components/parameters/SavingGoalIdParam' }],
+        responses: {
+          200: {
+            description: 'Saving goal restored',
+            content: {
+              'application/json': {
+                schema: { $ref: '#/components/schemas/SavingGoalResponse' },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+    },
+    '/saving-goals/{id}/contributions': {
+      get: {
+        tags: ['Saving Goals'],
+        summary: 'List contributions for a saving goal',
+        security: [{ BearerAuth: [] }],
+        parameters: [
+          { $ref: '#/components/parameters/SavingGoalIdParam' },
+          {
+            in: 'query',
+            name: 'dateFrom',
+            schema: { type: 'string', format: 'date-time' },
+          },
+          {
+            in: 'query',
+            name: 'dateTo',
+            schema: { type: 'string', format: 'date-time' },
+          },
+          {
+            in: 'query',
+            name: 'sortBy',
+            schema: {
+              type: 'string',
+              enum: ['amount', 'contributedAt', 'createdAt', 'updatedAt'],
+              default: 'contributedAt',
+            },
+          },
+          { $ref: '#/components/parameters/OrderParam' },
+          { $ref: '#/components/parameters/PageParam' },
+          { $ref: '#/components/parameters/LimitParam' },
+        ],
+        responses: {
+          200: {
+            description: 'Paginated contribution history',
+            content: {
+              'application/json': {
+                schema: {
+                  allOf: [
+                    { $ref: '#/components/schemas/SuccessResponse' },
+                    {
+                      type: 'object',
+                      properties: {
+                        data: {
+                          type: 'array',
+                          items: {
+                            $ref: '#/components/schemas/SavingContribution',
+                          },
+                        },
+                        meta: { $ref: '#/components/schemas/PaginationMeta' },
+                      },
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+      post: {
+        tags: ['Saving Goals'],
+        summary: 'Add a contribution',
+        description: 'Allowed only for an active, non-archived, incomplete goal. Progress and completion status update atomically.',
+        security: [{ BearerAuth: [] }],
+        parameters: [{ $ref: '#/components/parameters/SavingGoalIdParam' }],
+        requestBody: {
+          required: true,
+          content: {
+            'application/json': {
+              schema: {
+                $ref: '#/components/schemas/CreateSavingContributionBody',
+              },
+            },
+          },
+        },
+        responses: {
+          201: {
+            description: 'Contribution created with refreshed goal progress',
+            content: {
+              'application/json': {
+                schema: {
+                  allOf: [
+                    { $ref: '#/components/schemas/SuccessResponse' },
+                    {
+                      type: 'object',
+                      properties: {
+                        data: {
+                          $ref: '#/components/schemas/SavingContributionMutation',
+                        },
+                      },
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          409: { $ref: '#/components/responses/Conflict' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+    },
+    '/saving-goals/{id}/contributions/{contributionId}': {
+      put: {
+        tags: ['Saving Goals'],
+        summary: 'Update a saving contribution',
+        description: 'Recalculates goal progress and completion status atomically.',
+        security: [{ BearerAuth: [] }],
+        parameters: [
+          { $ref: '#/components/parameters/SavingGoalIdParam' },
+          { $ref: '#/components/parameters/SavingContributionIdParam' },
+        ],
+        requestBody: {
+          required: true,
+          content: {
+            'application/json': {
+              schema: {
+                $ref: '#/components/schemas/UpdateSavingContributionBody',
+              },
+            },
+          },
+        },
+        responses: {
+          200: {
+            description: 'Contribution and goal progress updated',
+            content: {
+              'application/json': {
+                schema: {
+                  allOf: [
+                    { $ref: '#/components/schemas/SuccessResponse' },
+                    {
+                      type: 'object',
+                      properties: {
+                        data: {
+                          $ref: '#/components/schemas/SavingContributionMutation',
+                        },
+                      },
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          409: { $ref: '#/components/responses/Conflict' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+      delete: {
+        tags: ['Saving Goals'],
+        summary: 'Delete a saving contribution',
+        description: 'Deletes a correction entry and recalculates goal progress atomically.',
+        security: [{ BearerAuth: [] }],
+        parameters: [
+          { $ref: '#/components/parameters/SavingGoalIdParam' },
+          { $ref: '#/components/parameters/SavingContributionIdParam' },
+        ],
+        responses: {
+          200: {
+            description: 'Contribution deleted and goal progress refreshed',
+            content: {
+              'application/json': {
+                schema: {
+                  allOf: [
+                    { $ref: '#/components/schemas/SuccessResponse' },
+                    {
+                      type: 'object',
+                      properties: {
+                        data: {
+                          type: 'object',
+                          properties: {
+                            id: { type: 'string', format: 'uuid' },
+                            goal: {
+                              $ref: '#/components/schemas/SavingGoal',
+                            },
+                          },
+                        },
+                      },
+                    },
+                  ],
+                },
+              },
+            },
+          },
+          401: { $ref: '#/components/responses/Unauthorized' },
+          404: { $ref: '#/components/responses/NotFound' },
+          409: { $ref: '#/components/responses/Conflict' },
+          422: { $ref: '#/components/responses/Validation' },
+        },
+      },
+    },
   },
 };

src/modules/saving-goals/saving-goal.controller.ts

+import { NextFunction, Request, Response } from 'express';
+import {
+  CreateSavingContributionDto,
+  CreateSavingGoalDto,
+  SavingContributionQueryDto,
+  SavingGoalQueryDto,
+  UpdateSavingContributionDto,
+  UpdateSavingGoalDto,
+} from './saving-goal.dto';
+import { SavingGoalService } from './saving-goal.service';
+
+export class SavingGoalController {
+  private readonly service = new SavingGoalService();
+
+  findAll = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const result = await this.service.findAll(
+        req.user.id,
+        req.query as unknown as SavingGoalQueryDto,
+      );
+
+      res.json({ success: true, ...result });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  findById = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const goal = await this.service.findById(req.user.id, req.params.id);
+
+      res.json({ success: true, data: goal });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  create = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const goal = await this.service.create(
+        req.user.id,
+        req.body as CreateSavingGoalDto,
+      );
+
+      res.status(201).json({ success: true, data: goal });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  update = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const goal = await this.service.update(
+        req.user.id,
+        req.params.id,
+        req.body as UpdateSavingGoalDto,
+      );
+
+      res.json({ success: true, data: goal });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  archive = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const goal = await this.service.archive(req.user.id, req.params.id);
+
+      res.json({
+        success: true,
+        message: 'Saving goal archived successfully',
+        data: goal,
+      });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  restore = async (req: Request, res: Response, next: NextFunction) => {
+    try {
+      const goal = await this.service.restore(req.user.id, req.params.id);
+
+      res.json({ success: true, data: goal });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  findContributions = async (
+    req: Request,
+    res: Response,
+    next: NextFunction,
+  ) => {
+    try {
+      const result = await this.service.findContributions(
+        req.user.id,
+        req.params.id,
+        req.query as unknown as SavingContributionQueryDto,
+      );
+
+      res.json({ success: true, ...result });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  createContribution = async (
+    req: Request,
+    res: Response,
+    next: NextFunction,
+  ) => {
+    try {
+      const result = await this.service.createContribution(
+        req.user.id,
+        req.params.id,
+        req.body as CreateSavingContributionDto,
+      );
+
+      res.status(201).json({ success: true, data: result });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  updateContribution = async (
+    req: Request,
+    res: Response,
+    next: NextFunction,
+  ) => {
+    try {
+      const result = await this.service.updateContribution(
+        req.user.id,
+        req.params.id,
+        req.params.contributionId,
+        req.body as UpdateSavingContributionDto,
+      );
+
+      res.json({ success: true, data: result });
+    } catch (error) {
+      next(error);
+    }
+  };
+
+  deleteContribution = async (
+    req: Request,
+    res: Response,
+    next: NextFunction,
+  ) => {
+    try {
+      const result = await this.service.deleteContribution(
+        req.user.id,
+        req.params.id,
+        req.params.contributionId,
+      );
+
+      res.json({
+        success: true,
+        message: 'Saving contribution deleted successfully',
+        data: result,
+      });
+    } catch (error) {
+      next(error);
+    }
+  };
+}

src/modules/saving-goals/saving-goal.dto.ts

+import { SavingGoalStatus } from '@prisma/client';
+
+export type SavingGoalSortField =
+  'name' | 'targetAmount' | 'targetDate' | 'createdAt' | 'updatedAt';
+export type SavingContributionSortField =
+  'amount' | 'contributedAt' | 'createdAt' | 'updatedAt';
+export type SortOrder = 'asc' | 'desc';
+
+export interface SavingGoalQueryDto {
+  search?: string;
+  status?: SavingGoalStatus;
+  dueFrom?: Date;
+  dueTo?: Date;
+  includeArchived: boolean;
+  sortBy: SavingGoalSortField;
+  order: SortOrder;
+  page: number;
+  limit: number;
+}
+
+export interface CreateSavingGoalDto {
+  name: string;
+  targetAmount: string;
+  currency: string;
+  targetDate: Date;
+  description?: string | null;
+  icon?: string | null;
+  color?: string | null;
+}
+
+export interface UpdateSavingGoalDto {
+  name?: string;
+  targetAmount?: string;
+  currency?: string;
+  targetDate?: Date;
+  description?: string | null;
+  icon?: string | null;
+  color?: string | null;
+  status?: Extract<SavingGoalStatus, 'ACTIVE' | 'PAUSED'>;
+}
+
+export interface SavingContributionQueryDto {
+  dateFrom?: Date;
+  dateTo?: Date;
+  sortBy: SavingContributionSortField;
+  order: SortOrder;
+  page: number;
+  limit: number;
+}
+
+export interface CreateSavingContributionDto {
+  amount: string;
+  contributedAt: Date;
+  note?: string | null;
+}
+
+export interface UpdateSavingContributionDto {
+  amount?: string;
+  contributedAt?: Date;
+  note?: string | null;
+}
+
+export interface SavingGoalProgressDto {
+  savedAmount: string;
+  remainingAmount: string;
+  progressPercentage: string;
+  contributionCount: number;
+  lastContributionAt: Date | null;
+  daysRemaining: number;
+  isOverdue: boolean;
+}
+
+export interface SavingGoalResponseDto {
+  id: string;
+  name: string;
+  targetAmount: string;
+  currency: string;
+  targetDate: Date;
+  description: string | null;
+  icon: string | null;
+  color: string | null;
+  status: SavingGoalStatus;
+  completedAt: Date | null;
+  isArchived: boolean;
+  createdAt: Date;
+  updatedAt: Date;
+  progress: SavingGoalProgressDto;
+}
+
+export interface SavingContributionResponseDto {
+  id: string;
+  savingGoalId: string;
+  amount: string;
+  contributedAt: Date;
+  note: string | null;
+  createdAt: Date;
+  updatedAt: Date;
+}

src/modules/saving-goals/saving-goal.repository.ts

+import { Prisma, SavingGoalStatus } from '@prisma/client';
+import { prisma } from '../../database/prisma.client';
+import {
+  CreateSavingContributionDto,
+  CreateSavingGoalDto,
+  SavingContributionQueryDto,
+  SavingContributionResponseDto,
+  SavingGoalQueryDto,
+  UpdateSavingContributionDto,
+  UpdateSavingGoalDto,
+} from './saving-goal.dto';
+
+const savingGoalSelect = {
+  id: true,
+  name: true,
+  targetAmount: true,
+  currency: true,
+  targetDate: true,
+  description: true,
+  icon: true,
+  color: true,
+  status: true,
+  completedAt: true,
+  isArchived: true,
+  createdAt: true,
+  updatedAt: true,
+} satisfies Prisma.SavingGoalSelect;
+
+const savingContributionSelect = {
+  id: true,
+  savingGoalId: true,
+  amount: true,
+  contributedAt: true,
+  note: true,
+  createdAt: true,
+  updatedAt: true,
+} satisfies Prisma.SavingContributionSelect;
+
+export type SavingGoalRecord = Prisma.SavingGoalGetPayload<{
+  select: typeof savingGoalSelect;
+}>;
+
+type SavingContributionRecord = Prisma.SavingContributionGetPayload<{
+  select: typeof savingContributionSelect;
+}>;
+
+export type SavingGoalTransaction = Prisma.TransactionClient;
+
+export interface SavingContributionSummary {
+  savingGoalId: string;
+  amount: Prisma.Decimal;
+  contributionCount: number;
+  lastContributionAt: Date | null;
+}
+
+type SavingGoalUpdateData = Omit<UpdateSavingGoalDto, 'status'> & {
+  status?: SavingGoalStatus;
+  completedAt?: Date | null;
+};
+
+function client(transaction?: SavingGoalTransaction) {
+  return transaction ?? prisma;
+}
+
+function toContributionResponse(
+  contribution: SavingContributionRecord,
+): SavingContributionResponseDto {
+  return {
+    ...contribution,
+    amount: contribution.amount.toFixed(2),
+  };
+}
+
+export class SavingGoalRepository {
+  async runSerializable<T>(
+    operation: (transaction: SavingGoalTransaction) => Promise<T>,
+  ): Promise<T> {
+    const maxAttempts = 3;
+
+    for (let attempt = 1; attempt <= maxAttempts; attempt += 1) {
+      try {
+        return await prisma.$transaction(operation, {
+          isolationLevel: Prisma.TransactionIsolationLevel.Serializable,
+        });
+      } catch (error) {
+        const shouldRetry =
+          error instanceof Prisma.PrismaClientKnownRequestError &&
+          error.code === 'P2034' &&
+          attempt < maxAttempts;
+
+        if (!shouldRetry) {
+          throw error;
+        }
+      }
+    }
+
+    throw new Error('Serializable transaction retry limit reached');
+  }
+
+  async findAll(userId: string, query: SavingGoalQueryDto) {
+    const {
+      search,
+      status,
+      dueFrom,
+      dueTo,
+      includeArchived,
+      sortBy,
+      order,
+      page,
+      limit,
+    } = query;
+    const where: Prisma.SavingGoalWhereInput = {
+      userId,
+      ...(status ? { status } : {}),
+      ...(includeArchived ? {} : { isArchived: false }),
+      ...(dueFrom || dueTo
+        ? {
+            targetDate: {
+              ...(dueFrom ? { gte: dueFrom } : {}),
+              ...(dueTo ? { lte: dueTo } : {}),
+            },
+          }
+        : {}),
+      ...(search
+        ? {
+            OR: [
+              {
+                name: { contains: search, mode: Prisma.QueryMode.insensitive },
+              },
+              {
+                description: {
+                  contains: search,
+                  mode: Prisma.QueryMode.insensitive,
+                },
+              },
+            ],
+          }
+        : {}),
+    };
+    const skip = (page - 1) * limit;
+    const [goals, total] = await prisma.$transaction([
+      prisma.savingGoal.findMany({
+        where,
+        select: savingGoalSelect,
+        orderBy: [{ [sortBy]: order }, { id: order }],
+        skip,
+        take: limit,
+      }),
+      prisma.savingGoal.count({ where }),
+    ]);
+
+    return {
+      data: goals,
+      meta: {
+        total,
+        page,
+        limit,
+        totalPages: Math.ceil(total / limit),
+      },
+    };
+  }
+
+  findById(userId: string, id: string, transaction?: SavingGoalTransaction) {
+    return client(transaction).savingGoal.findFirst({
+      where: { id, userId },
+      select: savingGoalSelect,
+    });
+  }
+
+  create(userId: string, data: CreateSavingGoalDto) {
+    return prisma.savingGoal.create({
+      data: {
+        userId,
+        ...data,
+      },
+      select: savingGoalSelect,
+    });
+  }
+
+  update(
+    id: string,
+    data: SavingGoalUpdateData,
+    transaction: SavingGoalTransaction,
+  ) {
+    return transaction.savingGoal.update({
+      where: { id },
+      data,
+      select: savingGoalSelect,
+    });
+  }
+
+  archive(id: string, transaction: SavingGoalTransaction) {
+    return transaction.savingGoal.update({
+      where: { id },
+      data: { isArchived: true },
+      select: savingGoalSelect,
+    });
+  }
+
+  restore(
+    id: string,
+    status: SavingGoalStatus,
+    completedAt: Date | null,
+    transaction: SavingGoalTransaction,
+  ) {
+    return transaction.savingGoal.update({
+      where: { id },
+      data: {
+        isArchived: false,
+        status,
+        completedAt,
+      },
+      select: savingGoalSelect,
+    });
+  }
+
+  async findSummaries(
+    savingGoalIds: string[],
+    transaction?: SavingGoalTransaction,
+  ): Promise<SavingContributionSummary[]> {
+    if (savingGoalIds.length === 0) {
+      return [];
+    }
+
+    const summaries = await client(transaction).savingContribution.groupBy({
+      by: ['savingGoalId'],
+      where: { savingGoalId: { in: savingGoalIds } },
+      _sum: { amount: true },
+      _count: { _all: true },
+      _max: { contributedAt: true },
+    });
+
+    return summaries.map((summary) => ({
+      savingGoalId: summary.savingGoalId,
+      amount: summary._sum.amount ?? new Prisma.Decimal(0),
+      contributionCount: summary._count._all,
+      lastContributionAt: summary._max.contributedAt,
+    }));
+  }
+
+  async findSummary(
+    savingGoalId: string,
+    transaction?: SavingGoalTransaction,
+  ): Promise<SavingContributionSummary> {
+    const result = await client(transaction).savingContribution.aggregate({
+      where: { savingGoalId },
+      _sum: { amount: true },
+      _count: { _all: true },
+      _max: { contributedAt: true },
+    });
+
+    return {
+      savingGoalId,
+      amount: result._sum.amount ?? new Prisma.Decimal(0),
+      contributionCount: result._count._all,
+      lastContributionAt: result._max.contributedAt,
+    };
+  }
+
+  async findContributions(
+    savingGoalId: string,
+    query: SavingContributionQueryDto,
+  ) {
+    const { dateFrom, dateTo, sortBy, order, page, limit } = query;
+    const where: Prisma.SavingContributionWhereInput = {
+      savingGoalId,
+      ...(dateFrom || dateTo
+        ? {
+            contributedAt: {
+              ...(dateFrom ? { gte: dateFrom } : {}),
+              ...(dateTo ? { lte: dateTo } : {}),
+            },
+          }
+        : {}),
+    };
+    const skip = (page - 1) * limit;
+    const [contributions, total] = await prisma.$transaction([
+      prisma.savingContribution.findMany({
+        where,
+        select: savingContributionSelect,
+        orderBy: [{ [sortBy]: order }, { id: order }],
+        skip,
+        take: limit,
+      }),
+      prisma.savingContribution.count({ where }),
+    ]);
+
+    return {
+      data: contributions.map(toContributionResponse),
+      meta: {
+        total,
+        page,
+        limit,
+        totalPages: Math.ceil(total / limit),
+      },
+    };
+  }
+
+  findContributionById(
+    savingGoalId: string,
+    id: string,
+    transaction: SavingGoalTransaction,
+  ) {
+    return transaction.savingContribution.findFirst({
+      where: { id, savingGoalId },
+      select: savingContributionSelect,
+    });
+  }
+
+  async createContribution(
+    savingGoalId: string,
+    data: CreateSavingContributionDto,
+    transaction: SavingGoalTransaction,
+  ) {
+    const contribution = await transaction.savingContribution.create({
+      data: {
+        savingGoalId,
+        ...data,
+      },
+      select: savingContributionSelect,
+    });
+
+    return toContributionResponse(contribution);
+  }
+
+  async updateContribution(
+    id: string,
+    data: UpdateSavingContributionDto,
+    transaction: SavingGoalTransaction,
+  ) {
+    const contribution = await transaction.savingContribution.update({
+      where: { id },
+      data,
+      select: savingContributionSelect,
+    });
+
+    return toContributionResponse(contribution);
+  }
+
+  deleteContribution(id: string, transaction: SavingGoalTransaction) {
+    return transaction.savingContribution.delete({
+      where: { id },
+      select: { id: true },
+    });
+  }
+}

src/modules/saving-goals/saving-goal.route.ts

+import { Router } from 'express';
+import { authMiddleware } from '../../middlewares/auth.middleware';
+import { validate } from '../../middlewares/validate.middleware';
+import { SavingGoalController } from './saving-goal.controller';
+import {
+  createSavingContributionSchema,
+  createSavingGoalSchema,
+  findSavingContributionsSchema,
+  findSavingGoalsSchema,
+  savingContributionParamsSchema,
+  savingGoalParamsSchema,
+  updateSavingContributionSchema,
+  updateSavingGoalSchema,
+} from './saving-goal.validation';
+
+const router = Router();
+const controller = new SavingGoalController();
+
+router.use(authMiddleware);
+
+router.get('/', validate(findSavingGoalsSchema, 'query'), controller.findAll);
+router.post('/', validate(createSavingGoalSchema), controller.create);
+router.get(
+  '/:id/contributions',
+  validate(savingGoalParamsSchema, 'params'),
+  validate(findSavingContributionsSchema, 'query'),
+  controller.findContributions,
+);
+router.post(
+  '/:id/contributions',
+  validate(savingGoalParamsSchema, 'params'),
+  validate(createSavingContributionSchema),
+  controller.createContribution,
+);
+router.put(
+  '/:id/contributions/:contributionId',
+  validate(savingContributionParamsSchema, 'params'),
+  validate(updateSavingContributionSchema),
+  controller.updateContribution,
+);
+router.delete(
+  '/:id/contributions/:contributionId',
+  validate(savingContributionParamsSchema, 'params'),
+  controller.deleteContribution,
+);
+router.get(
+  '/:id',
+  validate(savingGoalParamsSchema, 'params'),
+  controller.findById,
+);
+router.put(
+  '/:id',
+  validate(savingGoalParamsSchema, 'params'),
+  validate(updateSavingGoalSchema),
+  controller.update,
+);
+router.patch(
+  '/:id/restore',
+  validate(savingGoalParamsSchema, 'params'),
+  controller.restore,
+);
+router.delete(
+  '/:id',
+  validate(savingGoalParamsSchema, 'params'),
+  controller.archive,
+);
+
+export default router;

src/modules/saving-goals/saving-goal.service.ts

+import { Prisma, SavingGoalStatus } from '@prisma/client';
+import { AppError } from '../../common/errors/app-error';
+import { ERROR_CODE } from '../../common/errors/error-code';
+import {
+  CreateSavingContributionDto,
+  CreateSavingGoalDto,
+  SavingContributionQueryDto,
+  SavingGoalQueryDto,
+  SavingGoalResponseDto,
+  UpdateSavingContributionDto,
+  UpdateSavingGoalDto,
+} from './saving-goal.dto';
+import {
+  SavingContributionSummary,
+  SavingGoalRecord,
+  SavingGoalRepository,
+  SavingGoalTransaction,
+} from './saving-goal.repository';
+
+const MILLISECONDS_PER_DAY = 24 * 60 * 60 * 1000;
+
+export class SavingGoalService {
+  private readonly repository = new SavingGoalRepository();
+
+  async findAll(userId: string, query: SavingGoalQueryDto) {
+    const result = await this.repository.findAll(userId, query);
+    const summaries = await this.repository.findSummaries(
+      result.data.map((goal) => goal.id),
+    );
+    const summariesByGoal = new Map(
+      summaries.map((summary) => [summary.savingGoalId, summary]),
+    );
+    const data = result.data.map((goal) =>
+      this.toResponse(
+        goal,
+        summariesByGoal.get(goal.id) ?? this.emptySummary(goal.id),
+      ),
+    );
+
+    return { data, meta: result.meta };
+  }
+
+  async findById(userId: string, id: string) {
+    const goal = await this.findRecord(userId, id);
+    const summary = await this.repository.findSummary(id);
+
+    return this.toResponse(goal, summary);
+  }
+
+  async create(userId: string, data: CreateSavingGoalDto) {
+    const goal = await this.repository.create(userId, data);
+    return this.toResponse(goal, this.emptySummary(goal.id));
+  }
+
+  update(userId: string, id: string, data: UpdateSavingGoalDto) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, id, transaction);
+      this.ensureMutable(current);
+      const summary = await this.repository.findSummary(id, transaction);
+      if (
+        data.currency &&
+        data.currency !== current.currency &&
+        summary.contributionCount > 0
+      ) {
+        throw new AppError(
+          'Currency cannot be changed after contributions have been recorded',
+          409,
+          ERROR_CODE.SAVING_GOAL_CURRENCY_LOCKED,
+        );
+      }
+      const targetAmount = new Prisma.Decimal(
+        data.targetAmount ?? current.targetAmount,
+      );
+      const completion = this.resolveCompletion(
+        current,
+        summary,
+        targetAmount,
+        data.status,
+      );
+      const goal = await this.repository.update(
+        id,
+        {
+          ...data,
+          ...completion,
+        },
+        transaction,
+      );
+
+      return this.toResponse(goal, summary);
+    });
+  }
+
+  archive(userId: string, id: string) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, id, transaction);
+      const goal = current.isArchived
+        ? current
+        : await this.repository.archive(id, transaction);
+      const summary = await this.repository.findSummary(id, transaction);
+
+      return this.toResponse(goal, summary);
+    });
+  }
+
+  restore(userId: string, id: string) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, id, transaction);
+      const summary = await this.repository.findSummary(id, transaction);
+
+      if (!current.isArchived) {
+        return this.toResponse(current, summary);
+      }
+
+      const completion = this.resolveCompletion(
+        current,
+        summary,
+        current.targetAmount,
+      );
+      const goal = await this.repository.restore(
+        id,
+        completion.status,
+        completion.completedAt,
+        transaction,
+      );
+
+      return this.toResponse(goal, summary);
+    });
+  }
+
+  async findContributions(
+    userId: string,
+    savingGoalId: string,
+    query: SavingContributionQueryDto,
+  ) {
+    await this.findRecord(userId, savingGoalId);
+    return this.repository.findContributions(savingGoalId, query);
+  }
+
+  createContribution(
+    userId: string,
+    savingGoalId: string,
+    data: CreateSavingContributionDto,
+  ) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, savingGoalId, transaction);
+      this.ensureCanContribute(current);
+      const contribution = await this.repository.createContribution(
+        savingGoalId,
+        data,
+        transaction,
+      );
+      const { goal, summary } = await this.reconcileProgress(
+        current,
+        transaction,
+      );
+
+      return {
+        contribution,
+        goal: this.toResponse(goal, summary),
+      };
+    });
+  }
+
+  updateContribution(
+    userId: string,
+    savingGoalId: string,
+    contributionId: string,
+    data: UpdateSavingContributionDto,
+  ) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, savingGoalId, transaction);
+      this.ensureMutable(current);
+      await this.findContributionRecord(
+        savingGoalId,
+        contributionId,
+        transaction,
+      );
+      const contribution = await this.repository.updateContribution(
+        contributionId,
+        data,
+        transaction,
+      );
+      const { goal, summary } = await this.reconcileProgress(
+        current,
+        transaction,
+      );
+
+      return {
+        contribution,
+        goal: this.toResponse(goal, summary),
+      };
+    });
+  }
+
+  deleteContribution(
+    userId: string,
+    savingGoalId: string,
+    contributionId: string,
+  ) {
+    return this.repository.runSerializable(async (transaction) => {
+      const current = await this.findRecord(userId, savingGoalId, transaction);
+      this.ensureMutable(current);
+      await this.findContributionRecord(
+        savingGoalId,
+        contributionId,
+        transaction,
+      );
+      const deleted = await this.repository.deleteContribution(
+        contributionId,
+        transaction,
+      );
+      const { goal, summary } = await this.reconcileProgress(
+        current,
+        transaction,
+      );
+
+      return {
+        id: deleted.id,
+        goal: this.toResponse(goal, summary),
+      };
+    });
+  }
+
+  private async findRecord(
+    userId: string,
+    id: string,
+    transaction?: SavingGoalTransaction,
+  ) {
+    const goal = await this.repository.findById(userId, id, transaction);
+
+    if (!goal) {
+      throw new AppError('Saving goal not found', 404, ERROR_CODE.NOT_FOUND);
+    }
+
+    return goal;
+  }
+
+  private async findContributionRecord(
+    savingGoalId: string,
+    contributionId: string,
+    transaction: SavingGoalTransaction,
+  ) {
+    const contribution = await this.repository.findContributionById(
+      savingGoalId,
+      contributionId,
+      transaction,
+    );
+
+    if (!contribution) {
+      throw new AppError(
+        'Saving contribution not found',
+        404,
+        ERROR_CODE.NOT_FOUND,
+      );
+    }
+
+    return contribution;
+  }
+
+  private ensureMutable(goal: SavingGoalRecord) {
+    if (goal.isArchived) {
+      throw new AppError(
+        'Restore the saving goal before modifying it',
+        409,
+        ERROR_CODE.SAVING_GOAL_ARCHIVED,
+      );
+    }
+  }
+
+  private ensureCanContribute(goal: SavingGoalRecord) {
+    this.ensureMutable(goal);
+
+    if (goal.status === SavingGoalStatus.PAUSED) {
+      throw new AppError(
+        'Resume the saving goal before adding contributions',
+        409,
+        ERROR_CODE.SAVING_GOAL_PAUSED,
+      );
+    }
+
+    if (goal.status === SavingGoalStatus.COMPLETED) {
+      throw new AppError(
+        'The saving goal is already completed',
+        409,
+        ERROR_CODE.SAVING_GOAL_COMPLETED,
+      );
+    }
+  }
+
+  private async reconcileProgress(
+    current: SavingGoalRecord,
+    transaction: SavingGoalTransaction,
+  ) {
+    const summary = await this.repository.findSummary(current.id, transaction);
+    const completion = this.resolveCompletion(
+      current,
+      summary,
+      current.targetAmount,
+    );
+    const goal = await this.repository.update(
+      current.id,
+      completion,
+      transaction,
+    );
+
+    return { goal, summary };
+  }
+
+  private resolveCompletion(
+    current: SavingGoalRecord,
+    summary: SavingContributionSummary,
+    targetAmount: Prisma.Decimal,
+    requestedStatus?: Extract<SavingGoalStatus, 'ACTIVE' | 'PAUSED'>,
+  ) {
+    if (summary.amount.greaterThanOrEqualTo(targetAmount)) {
+      return {
+        status: SavingGoalStatus.COMPLETED,
+        completedAt: current.completedAt ?? new Date(),
+      };
+    }
+
+    return {
+      status:
+        requestedStatus ??
+        (current.status === SavingGoalStatus.COMPLETED
+          ? SavingGoalStatus.ACTIVE
+          : current.status),
+      completedAt: null,
+    };
+  }
+
+  private toResponse(
+    goal: SavingGoalRecord,
+    summary: SavingContributionSummary,
+  ): SavingGoalResponseDto {
+    const remainingAmount = Prisma.Decimal.max(
+      goal.targetAmount.minus(summary.amount),
+      new Prisma.Decimal(0),
+    );
+    const progressPercentage = summary.amount
+      .dividedBy(goal.targetAmount)
+      .times(100);
+    const now = new Date();
+
+    return {
+      ...goal,
+      targetAmount: goal.targetAmount.toFixed(2),
+      progress: {
+        savedAmount: summary.amount.toFixed(2),
+        remainingAmount: remainingAmount.toFixed(2),
+        progressPercentage: progressPercentage.toFixed(2),
+        contributionCount: summary.contributionCount,
+        lastContributionAt: summary.lastContributionAt,
+        daysRemaining: Math.max(
+          0,
+          Math.ceil(
+            (goal.targetDate.getTime() - now.getTime()) / MILLISECONDS_PER_DAY,
+          ),
+        ),
+        isOverdue:
+          goal.status !== SavingGoalStatus.COMPLETED && goal.targetDate < now,
+      },
+    };
+  }
+
+  private emptySummary(savingGoalId: string): SavingContributionSummary {
+    return {
+      savingGoalId,
+      amount: new Prisma.Decimal(0),
+      contributionCount: 0,
+      lastContributionAt: null,
+    };
+  }
+}

src/modules/saving-goals/saving-goal.validation.ts

+import { Prisma } from '@prisma/client';
+import { z } from 'zod';
+
+const amountSchema = z
+  .string()
+  .trim()
+  .regex(
+    /^(?:0|[1-9]\d{0,15})(?:\.\d{1,2})?$/,
+    'Amount must be a positive decimal string with at most 16 integer digits and 2 decimal places',
+  )
+  .refine(
+    (value) => new Prisma.Decimal(value).greaterThan(0),
+    'Amount must be greater than zero',
+  );
+const dateSchema = z
+  .string()
+  .datetime({
+    offset: true,
+    message: 'Date must be a valid ISO 8601 date-time',
+  })
+  .transform((value) => new Date(value));
+const currencySchema = z
+  .string()
+  .trim()
+  .length(3, 'Currency must contain exactly 3 letters')
+  .regex(/^[A-Za-z]{3}$/, 'Currency must contain only letters')
+  .transform((value) => value.toUpperCase());
+const nullableText = (max: number) =>
+  z.string().trim().max(max).nullable().optional();
+
+export const savingGoalParamsSchema = z.object({
+  id: z.string().uuid('Invalid saving goal id'),
+});
+
+export const savingContributionParamsSchema = z.object({
+  id: z.string().uuid('Invalid saving goal id'),
+  contributionId: z.string().uuid('Invalid saving contribution id'),
+});
+
+export const findSavingGoalsSchema = z
+  .object({
+    search: z.string().trim().min(1).max(200).optional(),
+    status: z.enum(['ACTIVE', 'PAUSED', 'COMPLETED']).optional(),
+    dueFrom: dateSchema.optional(),
+    dueTo: dateSchema.optional(),
+    includeArchived: z
+      .enum(['true', 'false'])
+      .transform((value) => value === 'true')
+      .optional()
+      .default('false'),
+    sortBy: z
+      .enum(['name', 'targetAmount', 'targetDate', 'createdAt', 'updatedAt'])
+      .optional()
+      .default('targetDate'),
+    order: z.enum(['asc', 'desc']).optional().default('asc'),
+    page: z.coerce.number().int().positive().optional().default(1),
+    limit: z.coerce.number().int().min(1).max(100).optional().default(20),
+  })
+  .refine(
+    (data) => !data.dueFrom || !data.dueTo || data.dueTo >= data.dueFrom,
+    { path: ['dueTo'], message: 'dueTo must be on or after dueFrom' },
+  );
+
+export const createSavingGoalSchema = z
+  .object({
+    name: z.string().trim().min(1, 'Name is required').max(100),
+    targetAmount: amountSchema,
+    currency: currencySchema.optional().default('VND'),
+    targetDate: dateSchema,
+    description: nullableText(500),
+    icon: nullableText(100),
+    color: z
+      .string()
+      .trim()
+      .regex(
+        /^#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})$/,
+        'Color must be a valid hex color',
+      )
+      .nullable()
+      .optional(),
+  })
+  .refine((data) => data.targetDate > new Date(), {
+    path: ['targetDate'],
+    message: 'targetDate must be in the future',
+  });
+
+export const updateSavingGoalSchema = z
+  .object({
+    name: z.string().trim().min(1, 'Name cannot be empty').max(100).optional(),
+    targetAmount: amountSchema.optional(),
+    currency: currencySchema.optional(),
+    targetDate: dateSchema.optional(),
+    description: nullableText(500),
+    icon: nullableText(100),
+    color: z
+      .string()
+      .trim()
+      .regex(
+        /^#(?:[0-9a-fA-F]{3}|[0-9a-fA-F]{6})$/,
+        'Color must be a valid hex color',
+      )
+      .nullable()
+      .optional(),
+    status: z.enum(['ACTIVE', 'PAUSED']).optional(),
+  })
+  .refine((data) => Object.keys(data).length > 0, {
+    message: 'At least one field is required',
+  })
+  .refine((data) => !data.targetDate || data.targetDate > new Date(), {
+    path: ['targetDate'],
+    message: 'targetDate must be in the future',
+  });
+
+export const findSavingContributionsSchema = z
+  .object({
+    dateFrom: dateSchema.optional(),
+    dateTo: dateSchema.optional(),
+    sortBy: z
+      .enum(['amount', 'contributedAt', 'createdAt', 'updatedAt'])
+      .optional()
+      .default('contributedAt'),
+    order: z.enum(['asc', 'desc']).optional().default('desc'),
+    page: z.coerce.number().int().positive().optional().default(1),
+    limit: z.coerce.number().int().min(1).max(100).optional().default(20),
+  })
+  .refine(
+    (data) => !data.dateFrom || !data.dateTo || data.dateTo >= data.dateFrom,
+    { path: ['dateTo'], message: 'dateTo must be on or after dateFrom' },
+  );
+
+export const createSavingContributionSchema = z
+  .object({
+    amount: amountSchema,
+    contributedAt: dateSchema.optional(),
+    note: nullableText(500),
+  })
+  .transform((data) => ({
+    ...data,
+    contributedAt: data.contributedAt ?? new Date(),
+  }))
+  .refine((data) => data.contributedAt <= new Date(), {
+    path: ['contributedAt'],
+    message: 'contributedAt cannot be in the future',
+  });
+
+export const updateSavingContributionSchema = z
+  .object({
+    amount: amountSchema.optional(),
+    contributedAt: dateSchema.optional(),
+    note: nullableText(500),
+  })
+  .refine((data) => Object.keys(data).length > 0, {
+    message: 'At least one field is required',
+  })
+  .refine((data) => !data.contributedAt || data.contributedAt <= new Date(), {
+    path: ['contributedAt'],
+    message: 'contributedAt cannot be in the future',
+  });

src/routes/index.ts

@@ -5,6 +5,7 @@ import walletRoute from '../modules/wallets/wallet.route';
 import categoryRoute from '../modules/categories/category.route';
 import transactionRoute from '../modules/transactions/transaction.route';
 import budgetRoute from '../modules/budgets/budget.route';
+import savingGoalRoute from '../modules/saving-goals/saving-goal.route';
 
 const router = Router();
 
@@ -18,5 +19,6 @@ router.use('/wallets', walletRoute);
 router.use('/categories', categoryRoute);
 router.use('/transactions', transactionRoute);
 router.use('/budgets', budgetRoute);
+router.use('/saving-goals', savingGoalRoute);
 
 export default router;