robojones/z1

const mergePorts = require('./mergePorts')

function verifyPorts(pack, prop, origin = 'package.json') {
    const ports = pack[prop]

    if (Array.isArray(ports)) {
        if (ports.length) {
            // remove non-numeral ports
            const numeralPorts = pack[prop].filter(p => typeof p === 'number')

            // remove duplicates
            const valid = mergePorts(numeralPorts)

            if (valid.length !== pack[prop].length) {
                throw new Error(`invalid ${prop} in ${origin}`)
            }

            // everything ok
            return
        }
    } else if (ports) {
        // wrong type
        throw new TypeError(prop + ' in package.json must be an array or undefined')
    }

    // undefined or empty array
    pack[prop] = null
}

module.exports = verifyPorts