Add MCU prefix for MCU registrations

internal/repository/registration.go

@@ -144,7 +144,7 @@ func registerPatientInTransaction(ctx context.Context, tx *sql.Tx, params Regist
 	now := time.Now().In(jakarta)
 	nowText := now.Format("2006-01-02 15:04:05")
 	regDate := params.RegistrationDate.Format("2006-01-02")
-	prefix := "P" + params.RegistrationDate.Format("0601")
+	prefix := registrationIDPrefix(params.RegistrationType, params.RegistrationDate)
 	regID, err := nextRegistrationID(ctx, tx, prefix)
 	if err != nil {
 		return RegistrationOutcome{}, err
@@ -489,6 +489,14 @@ func nextRegistrationID(ctx context.Context, tx *sql.Tx, prefix string) (string,
 	return fmt.Sprintf("%s%05d", prefix, number+1), nil
 }
 
+func registrationIDPrefix(registrationType int64, registrationDate time.Time) string {
+	prefix := "P"
+	if registrationType == 2 {
+		prefix = "MCU"
+	}
+	return prefix + registrationDate.Format("0601")
+}
+
 func registrationOutcome(statusCode int, success bool, status, message string, data any) RegistrationOutcome {
 	return RegistrationOutcome{HTTPStatus: statusCode, Success: success, Status: status, Message: message, Data: data}
 }

internal/repository/registration_prefix_test.go

@@ -0,0 +1,17 @@
+package repository
+
+import (
+	"testing"
+	"time"
+)
+
+func TestRegistrationIDPrefix(t *testing.T) {
+	registrationDate := time.Date(2026, time.September, 7, 0, 0, 0, 0, time.UTC)
+
+	if got, want := registrationIDPrefix(2, registrationDate), "MCU2609"; got != want {
+		t.Fatalf("MCU prefix = %q; want %q", got, want)
+	}
+	if got, want := registrationIDPrefix(1, registrationDate), "P2609"; got != want {
+		t.Fatalf("regular prefix = %q; want %q", got, want)
+	}
+}