const fileStream = require('fs');

export default class FileHelper {

    //Write the graph data structure schema in a file
    writeFile = (fileName, data) => {
        fileStream.writeFileSync(fileName, data,{ flag: 'w+' }, function(err) {
            if(err) {
                return console.log(err);
            }
            fileStream.close(fileName, (err) => {
                if (err) throw err;
                    console.log('No errors');
              });
            console.log("The file was saved");
        });
    }

    //Read file
    readFile = (fileName) => {
        try {
            const data = fileStream.readFileSync(fileName, 'utf8')
            return (data);
        } catch (err) {
            console.error(err)
        }
    }

    //Check for valid json string
    isJsonString = (str) => {
        try {
            JSON.parse(str);
        } catch (e) {
            return false;
        }
        return true;
    }

    isHashedFieldExist = ( field, fields) => {
        return fields.includes(field);
    }

}