Build a Pharmacy Ordering and Delivery App

Tables: medicines (name, category, price, requires_prescription, stock), orders (customer_id, items[], total, prescription_url, pharmacist_id, status, paystack_ref), deliveries (order_id, address, scheduled_time, rider_id, status).

OTC flow (most orders): customer selects medicines → cart total calculated → pay via Paystack → webhook confirms → order goes to pharmacy for picking.

Prescription flow: customer uploads prescription photo → order status: "awaiting_review" → pharmacist reviews (approves/rejects/modifies) → Paystack payment initialized → customer pays → order fulfilled.

async function createOrder(customerId, cartItems, prescriptionUrl) {
  var hasPrescriptionItems = cartItems.some(item => item.requires_prescription);
  var total = cartItems.reduce((sum, item) => sum + (item.price * item.qty), 0);

  var order = await db.orders.create({
    customer_id: customerId,
    items: cartItems,
    total,
    prescription_url: prescriptionUrl || null,
    status: hasPrescriptionItems ? 'awaiting_review' : 'pending_payment',
  });

  if (!hasPrescriptionItems) {
    // OTC: go straight to payment
    return await initializePayment(order);
  }
  // Prescription: wait for pharmacist to call initiatePaymentAfterApproval(orderId)
  return { order, message: 'Prescription submitted for review. You will receive a payment link once approved.' };
}

async function approveAndCharge(orderId, pharmacistId, finalAmount) {
  await db.orders.update(orderId, { status: 'approved', pharmacist_id: pharmacistId, total: finalAmount });
  return await initializePayment(await db.orders.findById(orderId));
}

if (event.event === 'charge.success') {
  var order = await db.orders.findByPaystackRef(event.data.reference);
  await db.orders.update(order.id, { status: 'paid' });

  // Notify pharmacy to start picking
  await notifyPharmacy(order.id);

  // Schedule delivery
  await db.deliveries.create({
    order_id: order.id,
    address: order.delivery_address,
    status: 'pending',
  });
}

// Track delivery stages
async function updateDelivery(deliveryId, newStatus, riderId) {
  var delivery = await db.deliveries.findById(deliveryId);
  await db.deliveries.update(deliveryId, { status: newStatus, rider_id: riderId });

  var statusMessages = {
    'picked_up': 'Your order has been picked up by our rider',
    'en_route': 'Your medicines are on the way',
    'delivered': 'Your order has been delivered',
  };

  await sendSMS(delivery.customer_phone, statusMessages[newStatus]);
}

For controlled substances and high-value prescription medicines, require an OTP or digital signature from the customer at delivery. This creates an audit trail showing the customer received their medicine.

See build a grocery delivery app with rider payouts for the delivery and rider payout side of this architecture.

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