uci-interrupt/src/interrupt.js

let bus = {}
import debounce from 'lodash.debounce'
import Base from '@uci/base'

import logger from '@uci-utils/logger'
let log = {}
// a pin makes a socket (server/listner) for each pin to which a consumer can be connected
class Interrupt extends Base {
  constructor(pin, opts = {}) {
    if (typeof pin !=='number') pin = parseInt(pin)  // make sure pin is a number!
    opts.conPacket = (opts.resetCmd && !opts.conPacket) ?  opts.conPacket : { cmd: opts.resetCmd, pin: pin }  // will use either option
    //  if opts .port/.path/.topic/.wport are base number/name to which pin number is added/appended (default being 9000,9100,'interrupt')
    // for specific port number pass itrt.port,itrn.path,itrm.topic,itrw.port which override it if present
    // conPacket is for uci socket.  This will send this command on connect, needed to initially reset the interrupt
    if (opts.path || opts.itrn) {
      opts.itrn = opts.itrn || {}
      if (opts.path && typeof opts.path !=='boolean') opts.path = opts.path + ':' + pin
      if (typeof opts.path ==='boolean') opts.path = ''
      opts.itrn.path =  opts.itrn.path || opts.path || 'interrupt:' + pin
      opts.itrn.conPacket = opts.conPacket
      opts.sockets = (opts.sockets ? opts.sockets + ',' : '') + 'itrn#s>n'
    }
    if (opts.topic || opts.itrm) {
      opts.itrm = opts.itrm || {}
      opts.itrm.topics = opts.itrm.topic || opts.topic +'/'+ pin || 'interrupt/' + pin
      opts.sockets = (opts.sockets ? opts.sockets + ',' : '') + 'itrm#s>m'
    }

    if (opts.itrw || opts.wport || opts.wport===0 ) {
      opts.itrw = opts.itrw || {}
      if (opts.wport) opts.wport = opts.wport + +pin
      opts.itrw.port = opts.itrw.port || opts.wport || 9100 + +pin
      opts.sockets = (opts.sockets ? opts.sockets + ',' : '') + 'itrw#s>w'
    }
    // default is a tcp socket server at 9000+pin
    if (opts.itrt || opts.port || opts.port===0 || !opts.sockets ) {
      opts.itrt = opts.itrt || {}
      if (opts.port) opts.port = opts.port + +pin
      opts.itrt.port = opts.itrt.port || opts.port || 9000 + +pin
      opts.itrt.conPacket = opts.conPacket
      opts.sockets = (opts.sockets ? opts.sockets + ',' : '') + 'itrt#s>t'
    }
    super(opts)
    this.id = (opts.id || 'interrupt') + ':' + pin
    log = logger({ name: 'interrupt', id: this.id })
    log.info({ pins: pin, opts: opts }, 'created interrupt with these opts')
    this.pin_num = +pin
    this.mock = opts.mock || process.env.MOCK
    this.wait = opts.wait || 0 // debounce is off by default
    this.dbopts = {
      maxWait: opts.maxwait || 500,
      leading: opts.leading || true,
      trailing: opts.trailing || false
    }
    this.edge = opts.edge
    this.pull = opts.pull
    this.pin = {} //set at init
    this.hook = opts.hook
    this.packet = opts.packet || {}
    this.packet.pin = pin
    this.packet.cmd = this.packet.cmd || opts.pushCmd || 'interrupt'
    this.packet.count = 0
  } // end constructor

  async init() {
    await super.init()
    // for cntrl-c exit of interrupt
    // create the pigio pin_num
    // TODO  check for rpi and pigpio,  if not available use onoff
    // wrap all needed commands so can call module for pigpio or onoff
    if (process.env.UCI_MOCK==='true') bus = await import('pigpio-mock')
    else bus = await import('pigpio')
    this.pin = new bus.Gpio(this.pin_num, {
      mode: bus.Gpio.INPUT,
      pullUpDown: this.pull || bus.Gpio.PUD_DOWN
      // do not! set edge here as it will start the emitter -- see pigio js
    })

    process.on('SIGINT', () => {
      this.exit()
        .then(resp => console.log('\n', resp)) // unexport on cntrl-c
        .catch(err => console.log('error:', err))
    })
    let cb = () => {}
    if (this.wait === 0) {
      cb = this._interruptProcess.bind(this, this.packet)
      log.info({ packet: this.packet },`starting interrupt on pin ${this.pin_num} without debounce`)
    } else {
      cb = debounce(
        this._interruptProcess.bind(this, this.packet),
        this.wait,
        this.dbopts
      )
    log.info({ packet: this.packet, wait: this.wait, options: this.dbopts },`starting interrupt on pin ${this.pin_num} with debounce wait:${this.wait}`)
    }
    this.pin.on('interrupt', cb)
    // rock n roll!!, start the pigpio interrupt
    if (!this.mock) this.pin.enableInterrupt(this.edge || bus.Gpio.RISING_EDGE)

  this.registerHook(defaultHook)

  } // end init

  // manual firing for testing
  async fire() {
    console.log('manually firing interrupt for pin', this.pin_num)
    this.pin.emit('interrupt', 1)
    return Promise.resolve({ status: 'fired' })
  }

  exit() {
    bus.terminate()
    return Promise.reject('keyboard termination...terminating interrupts')
  }

  // use hook to do more processing
  async _interruptProcess(packet) {
    packet.count += 1
    packet.time = new Date().getTime()
    packet.id = this.id
    if (this.hook) packet = await this._hookFunc.call(this,packet)
    log.info({ packet: packet }, 'packet pushing to all clients')
    this.push(packet)
  }


  registerHook(func) {
    this._hookFunc = func
  }

} // end Class

export default Interrupt


//default hook
async function defaultHook(packet) {
  // return a promise or use await if anything async happens in hook
  // new Promise((resolve) => {
  console.log('==========default hook =============')
  console.log(`pin ${packet.pin} on sbc gpio bus has thrown an interrupt`)
  console.log(`pushing to all connected socket client with cmd:${packet.cmd}`)
  console.dir('packet)
  console.log('replace by a new function with .registerHook(function) to overwrite this')
  console.log('Must be async/promise returning if anything async happens in your hook')
  console.log('This hook allow you to modify/add to the packet being pushed to connected clients')
  console.log('the function will be bound to the instance for complete access')
  console.log('if you pass a hash for .hook you can use it here as this.hook')
  console.log('the hook options contains', this.hook)
  console.log('by default the instance id will be attached to the packet before this')
  return packet
  // resolve(packet)
  // })
}