Build. Scale. Transform.

// MERN Stack + Next.js & TypeScript: Type-Safe Full-Stack Service
import { NextRequest, NextResponse } from 'next/server';
import mongoose, { Schema, model, Document } from 'mongoose';
import { z } from 'zod';

// 1. Strict TypeScript validation schema
export const OrderPayloadSchema = z.object({
  customerId: z.string().min(1),
  items: z.array(z.object({ sku: z.string(), qty: z.number().int().positive() })),
  total: z.number().nonnegative(),
});

export type OrderPayload = z.infer<typeof OrderPayloadSchema>;

// 2. MongoDB Document Schema with Mongoose
interface IOrder extends Document, OrderPayload {
  status: 'PENDING' | 'FULFILLED';
  createdAt: Date;
}

const OrderSchema = new Schema<IOrder>({
  customerId: { type: String, required: true, index: true },
  items: [{ sku: String, qty: Number }],
  total: { type: Number, required: true },
  status: { type: String, default: 'PENDING' },
  createdAt: { type: Date, default: Date.now },
});

// 3. Next.js App Router / Node.js API Handler with Type Safety
export async function POST(req: NextRequest): Promise<NextResponse> {
  const body = await req.json();
  const validated = OrderPayloadSchema.parse(body);

  await mongoose.connect(process.env.MONGODB_URI!);
  const Order = mongoose.models.Order || model<IOrder>('Order', OrderSchema);
  const order = await Order.create({ ...validated, status: 'FULFILLED' });

  return NextResponse.json({ success: true, orderId: order._id }, { status: 201 });
};