Mock class for browser development and testing SQLite on Ionic app

sql.ts

import { SQLiteDatabaseConfig } from '@ionic-native/sqlite';

//SQL file is loaded via script tag in index.html --> <script src="assets/sql/sql.js"></script>
declare var SQL;

export class SQLiteObject{
    _objectInstance: any;

    constructor(_objectInstance: any){
      this._objectInstance = _objectInstance;
    };

    executeSql(statement: string, params: any): Promise<any>{

      return new Promise((resolve,reject)=>{
        try {
          console.log(statement)
          var st = this._objectInstance.prepare(statement,params);
          var rows :Array<any> = [] ;
          while(st.step()) {
            var row = st.getAsObject();
            rows.push(row);
          }
          var payload = {
            rows: {
              item: function(i) {
                return rows[i];
              },
              length: rows.length
            },
            rowsAffected: this._objectInstance.getRowsModified() || 0,
            insertId: this._objectInstance.insertId || void 0
          };
          //save database after each sql query

          var arr : ArrayBuffer = this._objectInstance.export();
          localStorage.setItem("database",String(arr));
          resolve(payload);
        } catch(e){
          reject(e);
        }
      });
    };

    sqlBatch(statements: string[], params: any): Promise<any>{
      return new Promise((resolve,reject)=>{
        try {
          var rows :Array<any> = [];
          for (let statement of statements) {
            console.log(statement)
            var st = this._objectInstance.prepare(statement,params);
            while(st.step()) {
                var row = st.getAsObject();
                rows.push(row);
            }
          }
          var payload = {
            rows: {
              item: function(i) {
                return rows[i];
              },
              length: rows.length
            },
            rowsAffected: this._objectInstance.getRowsModified(),
            insertId: this._objectInstance.insertId || void 0
          };
          //save database after each sql query

          var arr : ArrayBuffer = this._objectInstance.export();
          localStorage.setItem("database",String(arr));
          resolve(payload);
        } catch(e){
          reject(e);
        }
      });
    };
}

/*
  Implemented using edited code from actual cordova plugin
*/
export class SQLitePorterMock {
    /**
     * Trims leading and trailing whitespace from a string
     * @param {string} str - untrimmed string
     * @returns {string} trimmed string
     */


    trimWhitespace(str){
      return str.replace(/^\s+/,"").replace(/\s+$/,"");
    }

    importSqlToDb(db, sql, opts = {}){
      try {
        const statementRegEx = /(?!\s|;|$)(?:[^;"']*(?:"(?:\\.|[^\\"])*"|'(?:\\.|[^\\'])*')?)*/g;
        var statements = sql
          .replace(/(?:\/\*(?:[\s\S]*?)\*\/)|(?:([\s;])+\/\/(?:.*)$)/gm,"") // strip out comments
          .match(statementRegEx);

        if(statements === null || (Array.isArray && !Array.isArray(statements))) statements = [];

        // Strip empty statements
        for(var i = 0; i < statements.length; i++){
          if(!statements[i]){
              delete statements[i];
          }
        }
        return db.sqlBatch(statements)
      } catch(e) {
        console.error(e.message);
      }
    }
}

export class SQLiteMock {

  public create(config: SQLiteDatabaseConfig): Promise<SQLiteObject> {
    var db;
    var storeddb = localStorage.getItem("database");

    if(storeddb) {
      var arr = storeddb.split(',');
      db = new SQL.Database(arr);
    }
    else {
       db = new SQL.Database();
    }

    return new Promise((resolve,reject)=>{
      resolve(new SQLiteObject(db));
    });
  }
}