# npm
npm install @gatex402/checkout

# yarn
yarn add @gatex402/checkout

# CDN
<script src="https://cdn.gatex402.com/v1/checkout.min.js"></script>

import { GateCheckout } from '@gatex402/checkout'

const gate = new GateCheckout({
  merchant: 'YOUR_WALLET_ADDRESS',
  network:  'mainnet',
  accept:   ['SOL', 'USDC', 'USDT'],
  theme:    'dark'
})

gate.open({ amount: 25, currency: 'USDC', memo: 'order-9281' })

gate.on('confirmed', (tx) => {
  console.log(tx.signature, tx.riskScore, tx.amount)
})

gate.open({
  amount:      10.00,
  currency:    'USDC',
  memo:        'invoice-0042',
  metadata:    { orderId: 'abc123' },
  redirectUrl: 'https://yoursite.com/success',
  expiry:      300
})

import { GateHeadless } from '@gatex402/checkout/headless'

const gate = new GateHeadless({
  merchant: 'MERCHANT_WALLET',
  network:  'mainnet',
  signer:   agentKeypair
})

const tx = await gate.pay({
  amount: 0.5, currency: 'SOL', memo: 'agent-task-7712'
})

const link = gate.createLink({
  amount: 50, currency: 'USDC',
  label: 'Logo Design — Final', expiry: '24h'
})
// → https://pay.gatex402.com/p/x7k9m2

npx gatex402 link --amount 50 --currency USDC --label "Invoice #42"

interface GateConfig {
  merchant: string; network?: 'mainnet'|'devnet'
  accept?: string[]; theme?: 'dark'|'light'|'auto'
  rpc?: string; webhook?: string
  riskThreshold?: number; autoConvert?: string
  escrow?: boolean
}

interface PaymentOptions {
  amount: number; currency?: string
  memo?: string; metadata?: Record<string,any>
  redirectUrl?: string; expiry?: number
}

interface Transaction {
  signature: string; amount: number
  currency: string; from: string; to: string
  riskScore: number; memo: string
  metadata: Record<string,any>; timestamp: number
}

interface EscrowContract {
  id: string; amount: number; currency: string
  status: 'locked'|'released'|'refunded'|'disputed'
  parties: { payer: string; payee: string }
  expiry: number
  release(): Promise<Transaction>
  refund(): Promise<Transaction>
}

import { GateHeadless } from '@gatex402/checkout/headless'
import { Keypair } from '@solana/web3.js'

const agent = new GateHeadless({
  merchant: 'TARGET_AGENT_WALLET',
  network:  'mainnet',
  signer:   Keypair.fromSecretKey(agentSecret)
})

const tx = await agent.pay({
  amount: 2.5, currency: 'USDC',
  memo: 'moltdmkt:skill:sentiment-v3',
  metadata: { protocol: 'x402', agent_id: 'agent-alpha-9' }
})

const escrow = await gate.escrow.create({
  amount: 100, currency: 'USDC',
  payee: 'WORKER_WALLET',
  expiry: 86400,
  memo: 'code-review-441'
})

// On task complete
await escrow.release()

// Or refund
await escrow.refund()

import { MicroStream } from '@gatex402/checkout/micro'

const stream = new MicroStream({
  merchant: 'API_PROVIDER_WALLET',
  signer: agentKeypair,
  ratePerCall: 0.001,
  settleEvery: 100,
  currency: 'USDC'
})

await stream.tick()  // +0.001 USDC
await stream.tick()  // +0.001 USDC
// auto-settles every 100 ticks

await stream.settle() // force settle

{
  "event": "payment.confirmed",
  "tx": {
    "signature": "5Uh7x...",
    "amount": 25.00,
    "currency": "USDC",
    "from": "7xKp...",
    "to": "9mRq...",
    "riskScore": 0.08,
    "memo": "order-9281"
  },
  "timestamp": 1711532400
}

const gate = new GateCheckout({
  merchant: 'YOUR_WALLET',
  accept: ['SOL', 'USDC', 'G8e2v6t4LfsJChH1LiF7xTiVVNR4u4R98VTmU6QWpump']
})