POST /api/v1/payments
{
  "amount": 1000,
  "currency": "USD",
  "method": "p2p",
  "callback_url": "https://example.com/callback"
}

Response:
{
  "status": "success",
  "transaction_id": "txn_abc123xyz",
  "payment_url": "http://localhost:8000/pay/txn_abc123xyz"
}

curl -X POST http://localhost:8000/api/v1/payments \
  -H 'Content-Type: application/json' \
  -d '{
    "amount": 1000,
    "currency": "USD",
    "method": "p2p",
    "callback_url": "https://example.com/callback"
  }'

$ch = curl_init('http://localhost:8000/api/v1/payments');
curl_setopt_array($ch, [
  CURLOPT_POST => true,
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => ['Content-Type: application/json'],
  CURLOPT_POSTFIELDS => json_encode([
    'amount' => 1000,
    'currency' => 'USD',
    'method' => 'p2p',
    'callback_url' => 'https://example.com/callback',
  ]),
]);
echo curl_exec($ch);

import requests
r = requests.post('<?php echo tmy_esc(SITE_URL); ?>/api/v1/payments', json={
    'amount': 1000,
    'currency': 'USD',
    'method': 'p2p',
    'callback_url': 'https://example.com/callback',
})
print(r.json())

fetch('<?php echo tmy_esc(SITE_URL); ?>/api/v1/payments', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    amount: 1000,
    currency: 'USD',
    method: 'p2p',
    callback_url: 'https://example.com/callback',
  }),
}).then(r => r.json()).then(console.log);