const express = require('express');
const bodyParser = require('body-parser');

const webpack = require('webpack');
const path = require('path');

const getConfig = require('server/config');
const { getLogger } = require('server/modules/logger');
const { getDBConnection } = require('server/modules/db');

const webpackConfig = require('../../webpack.config');

function healthEndpoint(config, db, logger, app) {
    app.get('/health', (req, res) => {
        res.send('OK');
    });
}

function setupDevServer(config, db, logger, app) {
    if (!config.__DEV__ || process.env.SKIP_APP === 'true') {
        return;
    }

    const compiler = webpack(webpackConfig);

    const serverOptions = {
        quiet: true,
        publicPath: webpackConfig.output.publicPath,
        hot: true
    };

    // eslint-disable-next-line global-require
    app.use(require('webpack-dev-middleware')(compiler, serverOptions));

    // eslint-disable-next-line global-require
    app.use(require('webpack-hot-middleware')(compiler));
}

function clientRoute(config, db, logger, app) {
    app.use(express.static(path.resolve(__dirname, '../../static')));
}

function setupMiddleware(app) {
    app.use(bodyParser.json());
}

async function run() {
    const config = getConfig();
    const logger = getLogger(config);

    try {
        const db = await getDBConnection(config, logger);

        const app = express();

        setupMiddleware(app);

        healthEndpoint(config, db, logger, app);
        setupDevServer(config, db, logger, app);
        clientRoute(config, db, logger, app);

        const port = process.env.PORT || 3000;

        app.listen(port, () => {
            logger.info('Listening on port', port);
        });

    } catch (err) {
        logger.error('Error setting up app');
        logger.error(err.stack);
    }
}

module.exports = {
    run
};