refactor: 결제 기능 리펙토링

* refactor: Pay 엔티티 필드 수정

* feat: 결제 준비, 결제 완료 DTO 생성

src/main/java/saphy/saphy/pay/domain/Pay.java

@@ -3,7 +3,6 @@
 import jakarta.persistence.*;
 import jakarta.persistence.Id;
 import java.math.BigDecimal;
-import java.time.LocalDateTime;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
@@ -27,6 +26,12 @@ public class Pay extends BaseEntity {
     @JoinColumn(name = "item_id", nullable = false)
     private Item item;
 
+    @Column(name = "merchant_id", unique = true)
+    private String merchantUid;
+
+    @Column(name = "imp_uid", unique = true)
+    private String impUid;
+
     @Column(name = "amount", nullable = false)
     private BigDecimal amount;
 
@@ -38,10 +43,12 @@ public class Pay extends BaseEntity {
     @Column(name = "status", nullable = false)
     private PayStatus status;
 
-    @Column(name = "transaction_id", unique = true)
-    private String transactionId;
+    public void setImpUid(String impUid) {
+        this.impUid = impUid;
+    }
 
-    @Column(name = "payment_date")
-    private LocalDateTime payDate;
+    public void setStatus(PayStatus status) {
+        this.status = status;
+    }
 
 }

src/main/java/saphy/saphy/pay/domain/repository/PayRepository.java

@@ -4,5 +4,6 @@
 import saphy.saphy.pay.domain.Pay;
 
 public interface PayRepository extends JpaRepository<Pay, Long> {
+    Pay findByMerchantUid(String merchantUid);
 
 }

src/main/java/saphy/saphy/pay/dto/request/PayCompleteRequest.java

@@ -0,0 +1,12 @@
+package saphy.saphy.pay.dto.request;
+
+import java.math.BigDecimal;
+import lombok.Getter;
+
+@Getter
+public class PayCompleteRequest {
+    private String merchantUid;
+    private Long itemId;
+    private String impUid;
+    private BigDecimal amount;
+}

src/main/java/saphy/saphy/pay/dto/request/PayPrepareRequest.java

@@ -0,0 +1,27 @@
+package saphy.saphy.pay.dto.request;
+
+import java.math.BigDecimal;
+import lombok.Getter;
+import saphy.saphy.item.domain.Item;
+import saphy.saphy.pay.domain.Pay;
+import saphy.saphy.pay.domain.PayMethod;
+import saphy.saphy.pay.domain.PayStatus;
+
+@Getter
+public class PayPrepareRequest {
+    private Long itemId;
+    private int quantity;
+    private BigDecimal amount;
+    private PayMethod payMethod;
+
+    public Pay toEntity(Item item, String merchantUid, BigDecimal amount, PayMethod payMethod ){
+        return Pay.builder()
+            .item(item)
+            .merchantUid(merchantUid)
+            .amount(amount)
+            .payMethod(payMethod)
+            .status(PayStatus.PENDING)
+            .build();
+    }
+
+}

src/main/java/saphy/saphy/pay/dto/response/PayCompleteResponse.java

@@ -0,0 +1,14 @@
+package saphy.saphy.pay.dto.response;
+
+import lombok.Getter;
+import saphy.saphy.pay.domain.PayStatus;
+
+@Getter
+public class PayCompleteResponse {
+    private PayStatus status;
+
+
+    public PayCompleteResponse(PayStatus status) {
+        this.status = status;
+    }
+}

src/main/java/saphy/saphy/pay/dto/response/PayPrepareResponse.java

@@ -0,0 +1,15 @@
+package saphy.saphy.pay.dto.response;
+
+import java.math.BigDecimal;
+import lombok.Getter;
+
+@Getter
+public class PayPrepareResponse {
+    private String merchantUid;
+    private BigDecimal amount;
+
+    public PayPrepareResponse(String merchantUid, BigDecimal amount) {
+        this.merchantUid = merchantUid;
+        this.amount = amount;
+    }
+}

src/main/java/saphy/saphy/pay/presentation/PayController.java

@@ -1,18 +1,20 @@
 package saphy.saphy.pay.presentation;
 
+import com.siot.IamportRestClient.exception.IamportResponseException;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import java.io.IOException;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import org.springframework.web.bind.annotation.GetMapping;
-import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import saphy.saphy.global.response.ApiResponse;
+import saphy.saphy.pay.dto.request.PayPrepareRequest;
+import saphy.saphy.pay.dto.response.PayPrepareResponse;
 import saphy.saphy.pay.service.PayService;
-import saphy.saphy.pay.dto.request.PayRequest;
-import saphy.saphy.pay.dto.response.PayResponse;
+import saphy.saphy.pay.dto.request.PayCompleteRequest;
+import saphy.saphy.pay.dto.response.PayCompleteResponse;
 
 @RestController
 @RequestMapping("/payments")
@@ -22,18 +24,16 @@
 public class PayController {
     private final PayService payService;
 
-    @PostMapping
-    public ApiResponse<PayResponse> processPayment(@RequestBody PayRequest request){
-        log.warn("impId >> " + request.getImpUid());
-        PayResponse response = payService.processPayment(request);
-
+    @PostMapping("/prepare")
+    public ApiResponse<PayPrepareResponse> preparePayment(@RequestBody PayPrepareRequest request) {
+        PayPrepareResponse response = payService.preparePay(request);
         return new ApiResponse<>(response);
     }
 
-    @GetMapping("/{paymentId}")
-    public ApiResponse<PayResponse> getPaymentDetails(@PathVariable Long paymentId) {
-        PayResponse response = payService.getPaymentDetails(paymentId);
-
+    @PostMapping("/complete")
+    public ApiResponse<PayCompleteResponse> completePayment(@RequestBody PayCompleteRequest request)
+        throws IamportResponseException, IOException {
+        PayCompleteResponse response = payService.completePay(request);
         return new ApiResponse<>(response);
     }
 }

src/main/java/saphy/saphy/pay/service/PayService.java

@@ -1,29 +1,32 @@
 package saphy.saphy.pay.service;
 
-import static saphy.saphy.global.exception.ErrorCode.INVALID_REQUEST;
+import static saphy.saphy.global.exception.ErrorCode.ITEM_OUT_OF_STOCK;
 import static saphy.saphy.global.exception.ErrorCode.PAY_FAILURE;
-import static saphy.saphy.global.exception.ErrorCode.PAY_INVALID;
-import static saphy.saphy.global.exception.ErrorCode.PAY_NOT_FOUND;
 import static saphy.saphy.global.exception.ErrorCode.PAY_PRICE_MISMATCH;
 
 import com.siot.IamportRestClient.IamportClient;
 import com.siot.IamportRestClient.exception.IamportResponseException;
+import com.siot.IamportRestClient.request.CancelData;
 import com.siot.IamportRestClient.response.IamportResponse;
 import com.siot.IamportRestClient.response.Payment;
 import jakarta.transaction.Transactional;
 import java.io.IOException;
+import java.math.BigDecimal;
 import java.util.Optional;
+import java.util.UUID;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import org.jetbrains.annotations.NotNull;
 import org.springframework.stereotype.Service;
 import saphy.saphy.global.exception.SaphyException;
 import saphy.saphy.item.domain.Item;
 import saphy.saphy.item.domain.repository.ItemRepository;
 import saphy.saphy.pay.domain.Pay;
+import saphy.saphy.pay.domain.PayStatus;
 import saphy.saphy.pay.domain.repository.PayRepository;
-import saphy.saphy.pay.dto.request.PayRequest;
-import saphy.saphy.pay.dto.response.PayResponse;
+import saphy.saphy.pay.dto.request.PayCompleteRequest;
+import saphy.saphy.pay.dto.request.PayPrepareRequest;
+import saphy.saphy.pay.dto.response.PayCompleteResponse;
+import saphy.saphy.pay.dto.response.PayPrepareResponse;
 
 @Service
 @RequiredArgsConstructor
@@ -34,56 +37,54 @@ public class PayService {
     private final IamportClient iamportClient;
 
 
-    /**
-     * 결제를 진행합니다.
-     * */
     @Transactional
-    public PayResponse processPayment(PayRequest request) {
+    public PayPrepareResponse preparePay(PayPrepareRequest request) {
         // Item을 상속받는 엔티티들이 존재하기에, Optional로 받아옴
         Optional<Item> optionalItem = itemRepository.findById(request.getItemId());
 
         Item item = optionalItem.get();
 
-        Payment iamportPayment = getIamportPayment(request);
+        if (item.getStock() < request.getQuantity()) {
+            throw SaphyException.from(ITEM_OUT_OF_STOCK);
+        }
 
-        // 물품 금액과 결제 금액이 같은지 검증
-        if (!iamportPayment.getAmount().equals(item.getPrice())) {
+        BigDecimal calculatedAmount = item.getPrice().multiply(BigDecimal.valueOf(request.getQuantity()));
+        if (!calculatedAmount.equals(request.getAmount())) {
             throw SaphyException.from(PAY_PRICE_MISMATCH);
         }
 
-        Pay pay = request.toEntity(item, iamportPayment);
-
+        String merchantUid = generateMerchantUid();
+        Pay pay = request.toEntity(item, merchantUid, calculatedAmount, request.getPayMethod());
         payRepository.save(pay);
 
-        // 재고 감소
-        item.decreaseStock(1);
+        item.decreaseStock(request.getQuantity());
         itemRepository.save(item);
 
-        return new PayResponse(pay.getId(), pay.getTransactionId(), pay.getStatus());
+        return new PayPrepareResponse(merchantUid, calculatedAmount);
     }
 
-    @NotNull
-    private Payment getIamportPayment(PayRequest request) {
-        IamportResponse<Payment> iamportResponse;
+    @Transactional
+    public PayCompleteResponse completePay(PayCompleteRequest request) throws IamportResponseException, IOException {
+        IamportResponse<Payment> payResponse = iamportClient.paymentByImpUid(request.getImpUid());
+
+        Pay pay = payRepository.findByMerchantUid(request.getMerchantUid());
 
-        try {
-            // PortOne 결제 확인
-            iamportResponse = iamportClient.paymentByImpUid(request.getImpUid());
+        if (payResponse.getResponse().getAmount().equals(pay.getAmount())) {
+            pay.setStatus(PayStatus.PAID);
+            pay.setImpUid(request.getImpUid());
+            payRepository.save(pay);
+
+            return new PayCompleteResponse(PayStatus.PAID);
+        } else {
+            iamportClient.cancelPaymentByImpUid(new CancelData(request.getImpUid(), true));
+            pay.setStatus(PayStatus.FAILED);
+            payRepository.save(pay);
 
-        } catch (IOException e) {
-            throw SaphyException.from(INVALID_REQUEST);
-        } catch (IamportResponseException | IllegalArgumentException e) {
             throw SaphyException.from(PAY_FAILURE);
         }
-
-        return Optional.ofNullable(iamportResponse.getResponse())
-        .orElseThrow(() -> SaphyException.from(PAY_INVALID));
     }
 
-    @Transactional
-    public PayResponse getPaymentDetails(Long paymentId) {
-        Pay pay = payRepository.findById(paymentId)
-            .orElseThrow(() -> SaphyException.from(PAY_NOT_FOUND));
-        return new PayResponse(pay.getId(), pay.getTransactionId(), pay.getStatus());
+    private String generateMerchantUid() {
+        return "ORD-" + UUID.randomUUID();
     }
 }

src/main/java/saphy/saphy/sales/domain/Sales.java

@@ -29,6 +29,6 @@ public class Sales extends BaseEntity {
     private Member member;
 
     @OneToOne(fetch = FetchType.LAZY) //여기 애매하긴 한데, 일단 1:1관계로 생각함.
-    @JoinColumn(name = "order_id")
+    @JoinColumn(name = "order_id") // 여기 이름 바꿔야 함
     private Purchase purchase;
 }