story-research-zapwall/lib/paymentPollingZapReceipt.ts

import { nostrService } from './nostr'
import { getPrimaryRelaySync } from './config'
import type { Event } from 'nostr-tools'

export function parseZapAmount(event: import('nostr-tools').Event): number {
  const amountTag = event.tags.find((tag) => tag[0] === 'amount')?.[1]
  return amountTag ? Math.floor(parseInt(amountTag, 10) / 1000) : 0
}

export function createZapReceiptSubscription(poolWithSub: import('@/types/nostr-tools-extended').SimplePoolWithSub, articlePubkey: string, articleId: string) {
  const filters = [
    {
      kinds: [9735],
      '#p': [articlePubkey],
      '#e': [articleId],
      limit: 1,
    },
  ]
  const relayUrl = getPrimaryRelaySync()
  return poolWithSub.sub([relayUrl], filters)
}

export function handleZapReceiptEvent(
  event: import('nostr-tools').Event,
  amount: number,
  recipientPubkey: string,
  finalize: (value: string | undefined) => void
): void {
  const amountInSats = parseZapAmount(event)
  if (amountInSats === amount && event.pubkey === recipientPubkey) {
    finalize(event.id)
  }
}

export function createZapReceiptPromise(
  sub: import('@/types/nostr-tools-extended').SimplePoolWithSub['sub'] extends (...args: any[]) => infer R ? R : never,
  amount: number,
  recipientPubkey: string
): Promise<string | undefined> {
  return new Promise((resolve) => {
    let resolved = false

    const finalize = (value: string | undefined) => {
      if (resolved) {
        return
      }
      resolved = true
      sub.unsub()
      resolve(value)
    }

    sub.on('event', (event: Event) => {
      handleZapReceiptEvent(event, amount, recipientPubkey, finalize)
    })

    sub.on('eose', () => finalize(undefined))
    setTimeout(() => finalize(undefined), 3000)
  })
}

export async function getZapReceiptId(
  articlePubkey: string,
  articleId: string,
  amount: number,
  recipientPubkey: string
): Promise<string | undefined> {
  try {
    const pool = nostrService.getPool()
    if (!pool) {
      return undefined
    }

    const poolWithSub = pool as import('@/types/nostr-tools-extended').SimplePoolWithSub
    const sub = createZapReceiptSubscription(poolWithSub, articlePubkey, articleId)
    return createZapReceiptPromise(sub, amount, recipientPubkey)
  } catch (error) {
    console.error('Error getting zap receipt ID', {
      articleId,
      recipientPubkey,
      error: error instanceof Error ? error.message : 'Unknown error',
    })
    return undefined
  }
}