added intentbased pg

src/main/java/com/billpaymentservice/bbps/controller/PaymentStartController.java

@@ -0,0 +1,31 @@
+package com.billpaymentservice.bbps.controller;
+
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.validation.annotation.Validated;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.billpaymentservice.bbps.dto.ResponseModel;
+import com.billpaymentservice.bbps.dto.request.PaymentStartUserRequest;
+import com.billpaymentservice.bbps.service.PaymentStartService;
+
+@RestController
+public class PaymentStartController {
+	private final PaymentStartService paymentStartService;
+
+	public PaymentStartController(PaymentStartService paymentStartService) {
+		this.paymentStartService = paymentStartService;
+	}
+	
+	@PostMapping(value = "/startWebPayment", consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)
+    public ResponseEntity<ResponseModel> startPayment(@Validated @RequestBody PaymentStartUserRequest paymentStartUserRequest) {
+        if (this.paymentStartService == null) {
+            // Defensive: if bean not injected, return failure
+            return ResponseEntity.badRequest().body(new ResponseModel("PaymentStartService not available", "FAILED", 400, null));
+        }
+        ResponseModel response = paymentStartService.startPayment(paymentStartUserRequest);
+        return ResponseEntity.ok(response);
+    }
+}