BlueWallet/blue_modules/fs.js

import { Alert, Linking, PermissionsAndroid, Platform } from 'react-native';
import RNFS from 'react-native-fs';
import Share from 'react-native-share';
import loc from '../loc';
import DocumentPicker from 'react-native-document-picker';
import { launchCamera, launchImageLibrary } from 'react-native-image-picker';
import { presentCameraNotAuthorizedAlert } from '../class/camera';
import { isDesktop } from '../blue_modules/environment';
import alert from '../components/Alert';
import { readFile } from './react-native-bw-file-access';
const LocalQRCode = require('@remobile/react-native-qrcode-local-image');

const writeFileAndExportToAndroidDestionation = async ({ filename, contents, destinationLocalizedString, destination }) => {
  const granted = await PermissionsAndroid.request(PermissionsAndroid.PERMISSIONS.WRITE_EXTERNAL_STORAGE, {
    title: loc.send.permission_storage_title,
    message: loc.send.permission_storage_message,
    buttonNeutral: loc.send.permission_storage_later,
    buttonNegative: loc._.cancel,
    buttonPositive: loc._.ok,
  });
  if (granted === PermissionsAndroid.RESULTS.GRANTED || Platform.Version >= 33) {
    const filePath = destination + `/${filename}`;
    try {
      await RNFS.writeFile(filePath, contents);
      alert(loc.formatString(loc._.file_saved, { filePath: filename, destination: destinationLocalizedString }));
    } catch (e) {
      console.log(e);
      alert(e.message);
    }
  } else {
    console.log('Storage Permission: Denied');
    Alert.alert(loc.send.permission_storage_title, loc.send.permission_storage_denied_message, [
      {
        text: loc.send.open_settings,
        onPress: () => {
          Linking.openSettings();
        },
        style: 'default',
      },
      { text: loc._.cancel, onPress: () => {}, style: 'cancel' },
    ]);
  }
};

const writeFileAndExport = async function (filename, contents) {
  if (Platform.OS === 'ios') {
    const filePath = RNFS.TemporaryDirectoryPath + `/${filename}`;
    await RNFS.writeFile(filePath, contents);
    await Share.open({
      url: 'file://' + filePath,
      saveToFiles: isDesktop,
    })
      .catch(error => {
        console.log(error);
      })
      .finally(() => {
        RNFS.unlink(filePath);
      });
  } else if (Platform.OS === 'android') {
    await writeFileAndExportToAndroidDestionation({
      filename,
      contents,
      destinationLocalizedString: loc._.downloads_folder,
      destination: RNFS.DownloadDirectoryPath,
    });
  }
};

/**
 * Opens & reads *.psbt files, and returns base64 psbt. FALSE if something went wrong (wont throw).
 *
 * @returns {Promise<string|boolean>} Base64 PSBT
 */
const openSignedTransaction = async function () {
  try {
    const res = await DocumentPicker.pickSingle({
      type: Platform.OS === 'ios' ? ['io.bluewallet.psbt', 'io.bluewallet.psbt.txn'] : [DocumentPicker.types.allFiles],
    });

    return await _readPsbtFileIntoBase64(res.uri);
  } catch (err) {
    if (!DocumentPicker.isCancel(err)) {
      alert(loc.send.details_no_signed_tx);
    }
  }

  return false;
};

const _readPsbtFileIntoBase64 = async function (uri) {
  const base64 = await RNFS.readFile(uri, 'base64');
  const stringData = Buffer.from(base64, 'base64').toString(); // decode from base64
  if (stringData.startsWith('psbt')) {
    // file was binary, but outer code expects base64 psbt, so we return base64 we got from rn-fs;
    // most likely produced by Electrum-desktop
    return base64;
  } else {
    // file was a text file, having base64 psbt in there. so we basically have double base64encoded string
    // thats why we are returning string that was decoded once;
    // most likely produced by Coldcard
    return stringData;
  }
};

const showImagePickerAndReadImage = () => {
  return new Promise((resolve, reject) =>
    launchImageLibrary(
      {
        title: null,
        mediaType: 'photo',
        takePhotoButtonTitle: null,
        maxHeight: 800,
        maxWidth: 600,
        selectionLimit: 1,
      },
      response => {
        if (!response.didCancel) {
          const asset = response.assets[0];
          if (asset.uri) {
            const uri = asset.uri.toString().replace('file://', '');
            LocalQRCode.decode(uri, (error, result) => {
              if (!error) {
                resolve(result);
              } else {
                reject(new Error(loc.send.qr_error_no_qrcode));
              }
            });
          }
        }
      },
    ),
  );
};

const takePhotoWithImagePickerAndReadPhoto = () => {
  return new Promise((resolve, reject) =>
    launchCamera(
      {
        title: null,
        mediaType: 'photo',
        takePhotoButtonTitle: null,
      },
      response => {
        if (response.uri) {
          const uri = response.uri.toString().replace('file://', '');
          LocalQRCode.decode(uri, (error, result) => {
            if (!error) {
              resolve(result);
            } else {
              reject(new Error(loc.send.qr_error_no_qrcode));
            }
          });
        } else if (response.error) {
          presentCameraNotAuthorizedAlert(response.error);
        }
      },
    ),
  );
};

const showFilePickerAndReadFile = async function () {
  try {
    const res = await DocumentPicker.pickSingle({
      type:
        Platform.OS === 'ios'
          ? [
              'io.bluewallet.psbt',
              'io.bluewallet.psbt.txn',
              'io.bluewallet.backup',
              DocumentPicker.types.plainText,
              'public.json',
              DocumentPicker.types.images,
            ]
          : [DocumentPicker.types.allFiles],
    });

    const uri = Platform.OS === 'ios' ? decodeURI(res.uri) : res.uri;
    // ^^ some weird difference on how spaces in filenames are treated on ios and android

    let file = false;
    if (res.uri.toLowerCase().endsWith('.psbt')) {
      // this is either binary file from ElectrumDesktop OR string file with base64 string in there
      file = await _readPsbtFileIntoBase64(uri);
      return { data: file, uri: decodeURI(res.uri) };
    }

    if (res?.type === DocumentPicker.types.images || res?.type?.startsWith('image/')) {
      return new Promise(resolve => {
        const uri2 = res.uri.toString().replace('file://', '');
        LocalQRCode.decode(decodeURI(uri2), (error, result) => {
          if (!error) {
            resolve({ data: result, uri: decodeURI(res.uri) });
          } else {
            resolve({ data: false, uri: false });
          }
        });
      });
    }

    file = await RNFS.readFile(uri);
    return { data: file, uri: decodeURI(res.uri) };
  } catch (err) {
    if (!DocumentPicker.isCancel(err)) {
      alert(err.message);
    }
    return { data: false, uri: false };
  }
};

// todo expand with other platforms if necessary
const readFileOutsideSandbox = filePath => {
  if (Platform.OS === 'ios') {
    return readFile(filePath);
  } else {
    return RNFS.readFile(filePath);
  }
};

module.exports.writeFileAndExport = writeFileAndExport;
module.exports.openSignedTransaction = openSignedTransaction;
module.exports.showFilePickerAndReadFile = showFilePickerAndReadFile;
module.exports.showImagePickerAndReadImage = showImagePickerAndReadImage;
module.exports.takePhotoWithImagePickerAndReadPhoto = takePhotoWithImagePickerAndReadPhoto;
module.exports.readFileOutsideSandbox = readFileOutsideSandbox;