mempool/backend/src/api/donations.ts

const config = require('../../mempool-config.json');
import * as request from 'request';
import { DB } from '../database';
import logger from '../logger';

class Donations {
  private notifyDonationStatusCallback: ((invoiceId: string) => void) | undefined;
  private options = {
    baseUrl: config.BTCPAY_URL,
    headers: {
      'Content-Type': 'application/json',
      'Authorization': config.BTCPAY_AUTH,
    },
  };

  sponsorsCache: any[] = [];

  constructor() {
    this.$updateCache();
  }

  async $updateCache() {
    try {
      this.sponsorsCache = await this.$getDonationsFromDatabase('handle, image');
    } catch (e) {
      logger.warn('Setting sponsorsCache failed ' + e.message || e);
    }
  }

  setNotfyDonationStatusCallback(fn: any): void {
    this.notifyDonationStatusCallback = fn;
  }

  createRequest(amount: number, orderId: string): Promise<any> {
    logger.notice('New invoice request. Handle: ' + orderId + ' Amount: ' + amount + ' BTC');

    const postData = {
      'price': amount,
      'orderId': orderId,
      'currency': 'BTC',
      'itemDesc': 'Sponsor mempool.space',
      'notificationUrl': config.BTCPAY_WEBHOOK_URL,
      'redirectURL': 'https://mempool.space/about'
    };
    return new Promise((resolve, reject) => {
      request.post({
        uri: '/invoices',
        json: postData,
        ...this.options,
      }, (err, res, body) => {
        if (err) { return reject(err); }
        const formattedBody = {
          id: body.data.id,
          amount: parseFloat(body.data.btcPrice),
          address: body.data.bitcoinAddress,
        };
        resolve(formattedBody);
      });
    });
  }

  async $handleWebhookRequest(data: any): Promise<void> {
    if (!data || !data.id) {
      return;
    }
    const response = await this.getStatus(data.id);
    logger.notice(`Received BTCPayServer webhook. Invoice ID: ${data.id} Status: ${response.status} BTC Paid: ${response.btcPaid}`);
    if (response.status !== 'complete' && response.status !== 'confirmed' && response.status !== 'paid') {
      return;
    }

    if (this.notifyDonationStatusCallback) {
      this.notifyDonationStatusCallback(data.id);
    }

    if (parseFloat(response.btcPaid) < 0.01) {
      return;
    }

    if (response.orderId !== '') {
      try {
        const userData = await this.$getTwitterUserData(response.orderId);
        const imageUrl = userData.profile_image_url.replace('normal', '200x200');
        const imageBlob = await this.$downloadProfileImageBlob(imageUrl);

        logger.debug('Creating database entry for donation with invoice id: ' + response.id);
        await this.$addDonationToDatabase(response.btcPaid, userData.screen_name, userData.id, response.id, imageUrl, imageBlob);
        this.$updateCache();
      } catch (e) {
        logger.err(`Error fetching twitter data for handle ${response.orderId}: ${e.message}`);
      }
    }
  }

  getSponsorImage(id: string): any | undefined {
    const sponsor = this.sponsorsCache.find((s) => s.handle === id);
    if (sponsor) {
      return sponsor.image;
    }
  }

  async $getDonationsFromDatabase(fields: string): Promise<any[]> {
    try {
      const connection = await DB.pool.getConnection();
      const query = `SELECT ${fields} FROM donations ORDER BY id DESC`;
      const [rows] = await connection.query<any>(query);
      connection.release();
      return rows;
    } catch (e) {
      logger.err('$getDonationsFromDatabase() error' + e);
      return [];
    }
  }

  private async $getOldDonations(): Promise<any[]> {
    try {
      const connection = await DB.pool.getConnection();
      const query = `SELECT * FROM donations WHERE twitter_id IS NULL AND handle != ''`;
      const [rows] = await connection.query<any>(query);
      connection.release();
      return rows;
    } catch (e) {
      logger.err('$getLegacyDonations() error' + e);
      return [];
    }
  }

  private getStatus(id: string): Promise<any> {
    return new Promise((resolve, reject) => {
      logger.debug('Fetching status for invoice: ' + id);
      request.get({
        uri: '/invoices/' + id,
        json: true,
        ...this.options,
      }, (err, res, body) => {
        if (err) { return reject(err); }
        logger.debug('Invoice status received: ' + JSON.stringify(body.data));
        resolve(body.data);
      });
    });
  }

  private async $addDonationToDatabase(btcPaid: number, handle: string, twitter_id: number | null,
    orderId: string, imageUrl: string, image: string): Promise<void> {
    try {
      const connection = await DB.pool.getConnection();
      const query = `INSERT IGNORE INTO donations(added, amount, handle, twitter_id, order_id, imageUrl, image) VALUES (NOW(), ?, ?, ?, ?, ?, FROM_BASE64(?))`;
      const params: (string | number | null)[] = [
        btcPaid,
        handle,
        twitter_id,
        orderId,
        imageUrl,
        image,
      ];
      const [result]: any = await connection.query(query, params);
      connection.release();
    } catch (e) {
      logger.err('$addDonationToDatabase() error' + e);
    }
  }

  private async $updateDonation(id: number, handle: string, twitterId: number, imageUrl: string, image: string): Promise<void> {
    try {
      const connection = await DB.pool.getConnection();
      const query = `UPDATE donations SET handle = ?, twitter_id = ?, imageUrl = ?, image = FROM_BASE64(?) WHERE id = ?`;
      const params: (string | number)[] = [
        handle,
        twitterId,
        imageUrl,
        image,
        id,
      ];
      const [result]: any = await connection.query(query, params);
      connection.release();
    } catch (e) {
      logger.err('$updateDonation() error' + e);
    }
  }

  private async $getTwitterUserData(handle: string): Promise<any> {
    return new Promise((resolve, reject) => {
      logger.debug('Fetching Twitter API data...');
      request.get({
        uri: `https://api.twitter.com/1.1/users/show.json?screen_name=${handle}`,
        json: true,
        headers: {
          Authorization: 'Bearer ' + config.TWITTER_BEARER_AUTH
        },
      }, (err, res, body) => {
        if (err) { return reject(err); }
        logger.debug('Twitter user data fetched:' + JSON.stringify(body.data));
        resolve(body);
      });
    });
  }

  private async $downloadProfileImageBlob(url: string): Promise<string> {
    return new Promise((resolve, reject) => {
      logger.debug('Fetching image blob...');
      request.get({
        uri: url,
        encoding: null,
      }, (err, res, body) => {
        if (err) { return reject(err); }
        logger.debug('Image downloaded.');
        resolve(Buffer.from(body, 'utf8').toString('base64'));
      });
    });
  }

  private async refreshSponsors(): Promise<void> {
    const oldDonations = await this.$getOldDonations();
    oldDonations.forEach(async (donation: any) => {
      logger.debug('Migrating donation for handle: ' + donation.handle);
      try {
        const twitterData = await this.$getTwitterUserData(donation.handle);
        const imageUrl = twitterData.profile_image_url.replace('normal', '200x200');
        const imageBlob = await this.$downloadProfileImageBlob(imageUrl);
        await this.$updateDonation(donation.id, twitterData.screen_name, twitterData.id, imageUrl, imageBlob);
      } catch (e) {
        logger.err('Failed to migrate donation for handle: ' + donation.handle + '. ' + (e.message || e));
      }
    });
  }
}

export default new Donations();