const Logger = require('./lib/utils/logger');
const config = require('./config');
const fs = require('fs');
const redis = require('redis');
const { commandOptions } = require('redis');
const { Worker } = require('worker_threads');
const path = require('path');

const logger = new Logger('presAnn Master');
logger.info("Running export-annotations");

const kickOffCollectorWorker = (jobId) => {
    return new Promise((resolve, reject) => {
        const worker = new Worker(path.join(__dirname, 'workers', 'collector.js'), { workerData: jobId });
        worker.on('message', resolve);
        worker.on('error', reject);
        worker.on('exit', (code) => {
            if (code !== 0)
                reject(new Error(`PresAnn Collector Worker stopped with exit code ${code}`));
        })
    })
}

(async () => {
    const client = redis.createClient({
        host: config.redis.host,
        port: config.redis.port,
        password: config.redis.password
      });
    
    await client.connect();
    
    client.on('error', (err) => logger.info('Redis Client Error', err));

    async function waitForJobs () {
        const queue = client.blPop(
            commandOptions({ isolated: true }),
            config.redis.channels.queue,
            0
        );

        let job = await queue;
        
        logger.info('Received job', job.element);
        const exportJob = JSON.parse(job.element);
        
        // Create folder in dropbox
        let dropbox = path.join(config.shared.presAnnDropboxDir, exportJob.jobId);
        fs.mkdirSync(dropbox, { recursive: true })
    
        // Drop job into dropbox as JSON
        fs.writeFile(path.join(dropbox, 'job'), job.element, function(err) {
            if(err) { return logger.error(err); }
        });

        kickOffCollectorWorker(exportJob.jobId)

        waitForJobs();
    }

    waitForJobs();
})();