robojones/z1

const net = require('net')
const path = require('path')
const fs = require('mz/fs')
const Connection = require('revents')
const z1 = require('../../remote')

const OPT = {
    allowHalfOpen: false,
}

/**
 * Creates a UNIX server to communicate with the z1 API.
 * @param {string} filename - The name for the UNIX socket.
 * @param {function} run - A function that gets called every time an object is received.
 */
function remoteServer(filename, run) {
    const file = path.resolve(filename)

    const server = net.createServer(OPT, socket => {
        socket.on('error', handle)

        const connection = new Connection(socket)

        connection.on('error', error => {
            connection.remoteEmit('error', error)
        })

        connection.on('command', async data => {
            try {
                const result = await run(data, connection)
                connection.remoteEmit('result', result)
            } catch (err) {
                connection.remoteEmit('error', err)
            }
        })

        connection.SIGINT = connection.once('SIGINT').then(() => {
            const msg = 'Received "SIGINT" from CLI. No new workers were started.'

            const error = new Error(msg)
            error.code = 'SIGINT'

            throw error
        })

        // prevent unhandled promise rejection warning
        connection.SIGINT.catch(() => {
        })
    })

    if (!global.test) {
        server.listen(file)
    }

    server.on('error', async err => {
        if (err.code !== 'EADDRINUSE') {
            handle(err)
            // try to restart server
            remoteServer(filename, run)
            return
        }

        const online = await z1._isOnline()

        if (online) {
            console.log('Another daemon process ist running. Exiting with exit code 0.')
            process.exit(0)
        } else {
            await fs.unlink(filename)
            console.log('Dead socket removed.')
            remoteServer(filename, run)
        }
    })

    remoteServer.server = server
}

remoteServer.Connection = Connection

module.exports = remoteServer