【ReactNative】スマホの機種変更後のデータ引き継ぎ機能を実装する〜アプリ実装済み〜

// onRestore()

import RNRestart from 'react-native-restart';

  const [backupDatas, setBackupDatas] = useState<string | undefined>('');
  const [parsedBkupDatas, setParsedBkupDatas] = useState<BackupListType[]>([]);

  const onRestore = () => {
    if (!isStep1Done) {
      onStep1();
    } else if (isStep1Done && !isStep2Done) {
      onStep2();
    } else if (isStep1Done && isStep2Done && !isStep3Done) {
      onStep3();
    } else if (isStep1Done && isStep2Done && isStep3Done && !isStep4Done) {
      onStep4();
    } else onStep5();
  };

// onStep1()

  const onStep1 = async () => {
    const j = await jcommonMapper.pickBackupFile();
    setBackupDatas(j);
  };

// pickBackupFile()

import {xor} from 'lodash';
import * as FileSystem from 'expo-file-system';
import * as DocumentPicker from 'expo-document-picker';

// 暗号化＋バックアップ版
const BackupListProperties = [
  'rvCommon',
  'preferredTheme',
  'items',
];

  pickBackupFile: async () => {
    const result = await DocumentPicker.getDocumentAsync({
      type: 'application/json',
    });
    if (result.canceled) return;
    if (result?.assets?.length) {
      const uri = result.assets.map(el => el.uri)[0];
      const fileData = await FileSystem.readAsStringAsync(uri);
      const decryptedData = jcommonMapper.jsonParse(fileData);
      const j = decryptedData.map(el => Object.keys(el)[0]);
      const a = xor(j, BackupListProperties);
      const isTargetDatas = a.length === 0;
      if (isTargetDatas) {
        return fileData;
      } else return undefined;
    }
  },

// onStep2()

const db = jsqlMapper.opendb();
const clear = async () => await AsyncStorage.clear();

  const onStep2 = async () => {
    await jcommonMapper.rvReset(clear);
    await jcommonMapper.dbReset(db);
  };

// rvReset()

  rvReset: async (
    storageClear: (callback?: Callback | undefined) => Promise<void>,
  ) => {
    try {
      await storageClear();
      console.log('🥕 AsyncStorageClear(): done');
    } catch (err) {
      return {isRvResetDone: false};
    }
    return {isRvResetDone: true};
  },

// dbReset()

dbReset: async (db: SQLiteDatabase) => {
    db.transaction(
      tx => {
        tx.executeSql('DROP TABLE IF EXISTS items');
        tx.executeSql('"CREATE TABLE IF NOT EXISTS items (id INTEGER PRIMARY KEY NOT NULL AUTOINCREMENT, done INT, value TEXT);"');
      },
      err => {
        console.log('!@# dbReset/err:', err);
        jcommonMapper.isDbResetDone(false);
        crashlytics().recordError(new Error(err.toString()), 'dbReset');
      },
      () => jcommonMapper.isDbResetDone(true),
    );
  },

// onStep3()

  const onStep3 = () => {
    const c = jcommonMapper.jsonParse(backupDatas);
    setParsedBkupDatas(c);
  };

// jsonParse() – 複合化する

  jsonParse: (fileData: string) => {
    /** Decrypt */
    const ciphertextOfBackuped = fileData;
    const bytes = CryptoJS.AES.decrypt(ciphertextOfBackuped, 'secret key 123');
    const decryptedData = JSON.parse(bytes.toString(CryptoJS.enc.Utf8));

    return decryptedData as BackupListType[];
  },

// onStep4()

  const onStep4 = async () => {
    await jcommonMapper.restoreRvdatas(parsedBkupDatas);
    await jcommonMapper.restoreDbdatas(db, parsedBkupDatas);
  };

// restoreRvdatas()

  restoreRvdatas: async (parsedBkupDatas: BackupListType[]) => {
    const re = await Promise.all(
      parsedBkupDatas.map(prd => {
        if (prd.rvCommon) {
          const _rvCommon = {
            ...prd.rvCommon,
            userId: rvCommonVar().userId,
            preferredTheme: rvCommonVar().preferredTheme.
            point: rvCommonVar().point,
          };
          rvCommonVar({..._rvCommon});
        }
      }),
    );
    return !!re.length;
  },

// restoreDbdatas()

  restoreDbdatas: async (
    db: SQLiteDatabase,
    parsedBkupDatas: BackupListType[],
  ) => {
    const items = compact(flatten(parsedBkupDatas.map(el => el.items)));
    db.transaction(
      tx => {
        items.map(h =>
          executeSql.insertItemsFromBkup(
            tx,
            h.done,
            h.value,
          ),
        );
      },
      err => {
        console.log('!@# restoreDbdatas/err:', err);
        jcommonMapper.isRestoreDbDatasDone(false);
      },
      () => jcommonMapper.isRestoreDbDatasDone(true),
    );
  },

// onStep5()

  const onStep5 = () => {
    RNRestart.Restart();
  };