const { promisify } = require('util');
const jsonfile = require('jsonfile');
const logger = require('log4js').getLogger();
const lz77 = require('lz77');
var lzw = require('json-lzw');

logger.level = 'trace';

const file = '../src/work/stations.json';
const outFile = '../src/work/stationsMap.json';
const compressed = '../src/work/stations.lzw';

const readFile = promisify(jsonfile.readFile);
const writeFile = promisify(jsonfile.writeFile);

function doConvert(obj) {
  const tempArray = [];
  for(const item of obj.locations)

    if ((item.lat !== 0) && (item.lon !== 0))
    // logger.debug(item.name);
      tempArray.push({ 'crs':item.crs, 'name':item.name, 'lat':item.lat, 'long':item.lon });

  // const locMap = new Map(tempArray);

  // logger.debug(locMap);

  const test = lz77.compress(JSON.stringify(tempArray), { 'minStringLength':3 });

  console.log(test);

  writeFile(outFile, tempArray)
    .then( () => {
      logger.debug('Saved...');
    }

    )
    .catch(err => {
      logger.error('Json failed to save');
      logger.warn(err);
    });
}

readFile(file)
  .then(obj => {
    logger.info('json loaded....');
    doConvert(obj);
  })
  .catch(err => {
    logger.error('Json failed to load');
    logger.warn(err);
  });

/*

jsonfile.readFile(file, (err, obj) => {
  if (err) {
    logger.error('Json failed to load');
    logger.warn(err);
  }
  else {
    logger.info('Json loaded...');
    doConvert(obj);
  }
});
*/