const configJSON = require('../config.json');
const logger = require('./logger.js');
const Watcher = require('./watcher.js');

const watchers = [];

function initialize() {
    return new Promise(function (resolve, reject) {
        if (configJSON == undefined || configJSON.watchers == undefined || configJSON.watchers.length == 0) {
            reject('error: no input devices defined');
        }
        var tmp = []
        for (var index = 0; index < configJSON.watchers.length; index++) {
            tmp.push(new Watcher(configJSON.watchers[index]));
        }
        Promise.all(tmp.map(check)).then(resolve);
    });
}
function check(watcher) {
    return new Promise(function (resolve, reject) {
        if (watcher == undefined) {
            reject();
        }
        watcher.check()
            .then(() => {
                logger.info('watcher \'' + watcher.device)
                watcher.start();
                watchers.push(watcher);
            })
            .catch((err) => {
                logger.error(err);d
            });
    });
}

function start() {
    logger.debug('starting ' + watchers.size + ' watcher(s)...');
    for (const watcher of watchers.entries()) {
        watcher[1].start();
    }
}

function stop() {
    const count = watchers.size;
    logger.info('stopping all ' + count + ' watchers...');
    for (var index = 0; index < count; index++) {
        var watcher = watchers[index];
        logger.debug('stopping watcher ' + watcher.id + '...');
        watcher.kill();
    }
}

function callback(err, id, code) {
    this.watchers.delete(id);
    logger.debug('removed watcher \'' + id + '\'');
}

module.exports = {
    initialize,
    start,
    stop
}