Thingy Disco

thingy-disco.js

const noble = require('noble')

const thingyServiceUUID = 'ef6801009b3549339b1052ffa9740042'
const UserInterfaceServiceUUID = 'ef6803009b3549339b1052ffa9740042'
const ButtonCharacteristicUUID = 'ef6803029b3549339b1052ffa9740042'
const LEDCharacteristicUUID = 'ef6803019b3549339b1052ffa9740042'

noble.on('stateChange',  state => {
    if (state === 'poweredOn') {
        console.log('scanning for Thingy')
        noble.startScanning([thingyServiceUUID], false)
    } else {
        noble.stopScanning()
    }
})

let led, button

noble.on('discover', peripheral => {
    noble.stopScanning()
    peripheral.connect(err => {
        if (err !== null) console.error(err)
        peripheral.discoverServices([UserInterfaceServiceUUID], (err, [service]) => {
            service.discoverCharacteristics([ButtonCharacteristicUUID, LEDCharacteristicUUID], (err, characteristics) => {
                characteristics.forEach(characteristic => {
                    switch(characteristic.uuid) {
                        case LEDCharacteristicUUID:
                            led = characteristic
                            break
                        case ButtonCharacteristicUUID:
                            button = characteristic
                            break
                    }
                    if (led && button) run();
                })
            })
        })
    })
})

const run = () => {
    button.discoverDescriptors((err, [descriptor]) => {
        const b = new Buffer(2)
        b.writeUInt8(1, 0)
        descriptor.writeValue(b, err => {
            if (err !== null) {
                console.error(`Failed to enable notifiy: ${err}`)
            } else {
                console.log('Listening for button press ...')
            }
        })
    })
    button.on('data', (data, isNotification) => {
        if (!isNotification) return
        if (data.toString('hex') !== '01') return
        const b = new Buffer(4)
        b.writeUInt8(1, 0)
        b.writeUInt8(Math.round(Math.random() * 255), 1)
        b.writeUInt8(Math.round(Math.random() * 255), 2)
        b.writeUInt8(Math.round(Math.random() * 255), 3)
        led.write(b, false, err => {
            if (err !== null) console.error(err)
            console.log(`Color set to: #${b.toString('hex').substr(2)}`)
        })
    })
}