feat: add payment module and factory

src/modules/payments/factories/payment.factory.ts

@@ -0,0 +1,28 @@
+import { BadGatewayException, Injectable } from "@nestjs/common";
+
+import { PaymentMessage } from "../../../common/enums/message.enum";
+import { GatewayEnum } from "../enums/gateway.enum";
+import { ZarinpalGateway } from "../gateways/zarinpal.gateway";
+import { GatewayType } from "../types/gateway.type";
+
+@Injectable()
+export class PaymentGatewayFactory {
+  constructor(private readonly ZarinpalGateway: ZarinpalGateway) {}
+
+  //************************ *
+  getPaymentGateway(provider: GatewayType) {
+    switch (provider) {
+      case "zarinpal":
+        return this.ZarinpalGateway;
+
+      default:
+        throw new BadGatewayException(PaymentMessage.PAYMENT_GATEWAY_NOT_FOUND);
+    }
+  }
+
+  //************************ */
+  getAvailablePaymentGateways() {
+    const gateways = [{ name: GatewayEnum.ZARINPAL }];
+    return { gateways };
+  }
+}