story-research-zapwall/lib/automaticTransfer.ts

import { calculateArticleSplit, calculateReviewSplit } from './platformCommissions'

/**
 * Automatic transfer service
 * Handles automatic forwarding of author/reviewer portions after payment
 *
 * Since WebLN doesn't support BOLT12 with split, the platform receives the full amount
 * and must automatically forward the author/reviewer portion.
 *
 * This service tracks transfers and ensures they are executed correctly.
 */
export interface TransferResult {
  success: boolean
  transferInvoiceId?: string
  error?: string
  amount: number
  recipient: string
}

export class AutomaticTransferService {
  /**
   * Transfer author portion after article payment
   * Creates a Lightning invoice from the platform to the author
   */
  private logTransferRequired(params: {
    type: 'article' | 'review'
    id: string
    pubkey: string
    amount: number
    recipient: string
    platformCommission: number
  }): void {
    const logData = {
      [params.type === 'article' ? 'articleId' : 'reviewId']: params.id,
      [params.type === 'article' ? 'articlePubkey' : 'reviewerPubkey']: params.pubkey,
      amount: params.amount,
      recipient: params.recipient,
      platformCommission: params.platformCommission,
      timestamp: new Date().toISOString(),
    }
    console.warn(`Automatic transfer required${params.type === 'review' ? ' for review' : ''}`, logData)
  }

  private buildTransferError(error: unknown, recipient: string, amount: number = 0): TransferResult {
    const errorMessage = error instanceof Error ? error.message : 'Unknown error'
    return {
      success: false,
      error: errorMessage,
      amount,
      recipient,
    }
  }

  async transferAuthorPortion(
    authorLightningAddress: string,
    articleId: string,
    articlePubkey: string,
    paymentAmount: number
  ): Promise<TransferResult> {
    return this.transferPortion({
      type: 'article',
      id: articleId,
      pubkey: articlePubkey,
      recipient: authorLightningAddress,
      paymentAmount,
      computeSplit: calculateArticleSplit,
      getRecipientAmount: (split) => split.author,
      missingRecipientError: 'Author Lightning address not available',
      errorLogMessage: 'Error transferring author portion',
    })
  }

  /**
   * Transfer reviewer portion after review reward payment
   */
  async transferReviewerPortion(
    reviewerLightningAddress: string,
    reviewId: string,
    reviewerPubkey: string,
    paymentAmount: number
  ): Promise<TransferResult> {
    return this.transferPortion({
      type: 'review',
      id: reviewId,
      pubkey: reviewerPubkey,
      recipient: reviewerLightningAddress,
      paymentAmount,
      computeSplit: calculateReviewSplit,
      getRecipientAmount: (split) => split.reviewer,
      missingRecipientError: 'Reviewer Lightning address not available',
      errorLogMessage: 'Error transferring reviewer portion',
    })
  }

  private async transferPortion<TSplit extends { platform: number }>(params: {
    type: 'article' | 'review'
    id: string
    pubkey: string
    recipient: string
    paymentAmount: number
    computeSplit: (amount: number) => TSplit
    getRecipientAmount: (split: TSplit) => number
    missingRecipientError: string
    errorLogMessage: string
  }): Promise<TransferResult> {
    try {
      const split = params.computeSplit(params.paymentAmount)
      const recipientAmount = params.getRecipientAmount(split)

      if (!params.recipient) {
        return this.buildMissingRecipientResult({
          error: params.missingRecipientError,
          recipient: params.recipient,
          amount: recipientAmount,
        })
      }

      this.logAndTrackTransferRequirement({
        type: params.type,
        id: params.id,
        pubkey: params.pubkey,
        recipient: params.recipient,
        amount: recipientAmount,
        platformCommission: split.platform,
      })

      return { success: true, amount: recipientAmount, recipient: params.recipient }
    } catch (error) {
      this.logTransferError({ message: params.errorLogMessage, id: params.id, pubkey: params.pubkey, error })
      return this.buildTransferError(error, params.recipient)
    }
  }

  private buildMissingRecipientResult(params: { error: string; recipient: string; amount: number }): TransferResult {
    return { success: false, error: params.error, amount: params.amount, recipient: params.recipient }
  }

  private logAndTrackTransferRequirement(params: {
    type: 'article' | 'review'
    id: string
    pubkey: string
    recipient: string
    amount: number
    platformCommission: number
  }): void {
    this.logTransferRequired({
      type: params.type,
      id: params.id,
      pubkey: params.pubkey,
      amount: params.amount,
      recipient: params.recipient,
      platformCommission: params.platformCommission,
    })
    this.trackTransferRequirement({
      type: params.type,
      id: params.id,
      recipientPubkey: params.pubkey,
      amount: params.amount,
      recipientAddress: params.recipient,
    })
  }

  private logTransferError(params: { message: string; id: string; pubkey: string; error: unknown }): void {
    console.error(params.message, {
      id: params.id,
      pubkey: params.pubkey,
      error: params.error instanceof Error ? params.error.message : 'Unknown error',
      timestamp: new Date().toISOString(),
    })
  }

  /**
   * Track transfer requirement for later processing
   * In production, this would be stored in a database or queue
   */
  private trackTransferRequirement(
    params: {
      type: 'article' | 'review'
      id: string
      recipientPubkey: string
      amount: number
      recipientAddress: string
    }
  ): void {
    // In production, this would:
    // 1. Store in a database/queue for processing
    // 2. Trigger automatic transfer via platform's Lightning node
    // 3. Update tracking when transfer is complete

    console.warn('Transfer requirement tracked', {
      type: params.type,
      id: params.id,
      recipientPubkey: params.recipientPubkey,
      amount: params.amount,
      recipientAddress: params.recipientAddress,
      timestamp: new Date().toISOString(),
    })
  }
}

export const automaticTransferService = new AutomaticTransferService()