"use strict";

// External dependencies
const fs = require('fs'),
      transform = require('stream-transform'),
      parse = require('csv-parse'),
      gdelt_formatter = require('./gdelt/formatter.js'),
      esIndexer = require('./es.js'),
      concurrency = 10000;

function indexGdeltFile(filename) {
  const input = fs.createReadStream(__dirname+`/${filename}`);

  const indexer = new esIndexer({_index: 'elastic_gdelt', _type: 'event'});
  const parser = parse({delimiter: '\t'});


  const formatter = transform(function(record, callback){
	callback(null, gdelt_formatter(record));
  }, {parallel: concurrency});

  const elastic_indexer = transform(function(record, callback){
	indexer.indexDoc(record,callback);
  }, {parallel: concurrency});

  input.on('end', () => {
	console.log("Finished reading CSV file.");
	//  TODO: finish indexing handler...
  });

  input.pipe(parser)
	.pipe(formatter)
	.pipe(elastic_indexer)
	.pipe(process.stdout);
}

module.exports = {
  indexGdeltFile
}