///***************** HOME ASSISTANT ************************
// for uci mqtt discovery in HA


const STATE_TOPIC = 'state'
const STATE_CMD = 'state'
const ENTITY = 'switch'
const DISCOVERY = 'homeassistant'
const NAMESPACE = 'uci'
const COMMAND_TOPIC = 'set'  // will use payload as the command

function register(name,opts={}) {

  const topic = `${opts.discovery || DISCOVERY}/` +
    `${opts.entity || ENTITY}/` +
    `${opts.namespace || NAMESPACE ? `${opts.namespace || NAMESPACE }` :''}`
  console.log('subscription topic for HA',`${topic}/#`)
  this.getSocket(name).subscribe(`${topic}/#`)

  this.beforeProcessHook(async (packet) => {
    // console.log('incoming ha mqtt packet to modify')
    // console.dir(packet)
    // let modified = Object.assign({},packet)
    const topic = packet.cmd.split('/')
    const cmd = topic.pop()
    const id = topic.pop()
    // console.log(cmd, id)
    if (cmd=== (opts.state || STATE_TOPIC)) return null  // ignore state commands (avoid infiite loop)
    else if (cmd===(opts.command||COMMAND_TOPIC)) packet.cmd = packet.data.toLowerCase()
    else packet.cmd = cmd
    delete packet.data
    Object.assign(packet,this.entities.find(ent => ent.id === id))
    // console.log('translated to uci packet')
    // console.dir(packet)
    return packet
  },
  {name:name})

  this.afterProcessHook(async (packet) => {
    if (packet.error) {
      let npacket = {}
      npacket.cmd = 'error'
      npacket.payload = JSON.stringify(packet)
      return npacket
    }
    // console.log('after process', packet)
    return packet
  },
  {name:name})

  this.beforeSendHook(async (packet) => {
    if (packet.cmd === (opts.stateCmd || STATE_CMD)) {
      // console.log('preparing state topic/payload')
      if (packet.state && packet.gpio) {
        let mpacket = {
          cmd: `${topic}/${packet.id}/${opts.stateCmd || STATE_CMD}`,
          payload: ((packet.state || {})[packet.gpio.toString()] || '').toUpperCase()
        }
        // console.log('=============modified packet being pushed to broker================')
        // console.dir(mpacket)
        // console.log('================')
        return mpacket
      }
      // else console.log('bad state packet state/gpio',packet.state,packet.gpio)
    }
    // console.log('packet ignored, nothing sent to to HA')
    return null  // only send/publish the required topic
  },
  {name:name})

}

export default register

function init(mqtt,entities,opts={}) {
  console.log('initializing ha mqtt discovery')
  entities.forEach(ent => {
    const topic = `${opts.discovery || DISCOVERY}/` +
      `${opts.entity || ENTITY}/` +
      `${opts.namespace || NAMESPACE ? `${opts.namespace || NAMESPACE }/` :''}` +
      `${ent.id}`
    let payload = {
      name:`${opts.namespace || NAMESPACE ? `${opts.namespace || NAMESPACE }_` :''}${ent.id}`,
      command_topic:`${topic}/${opts.command || COMMAND_TOPIC}`,
      state_topic: `${topic}/${opts.state || STATE_TOPIC}`,
      json_attributes_topic:`${topic}/${opts.state || STATE_TOPIC}`,
      json_attributes_template:'{{ value_json.alias | tojson }}',
    }
    payload = JSON.stringify(payload)
    console.log('------ sending discovery payload to HA for ',ent.alias,':',ent.id,'-----')
    console.log('topic=>',`${topic}/config`)
    // console.log(payload)
    mqtt.publish(`${topic}/info`,null)  // clear existing
    mqtt.publish(`${topic}/config`,payload,{retain:true})
  })

}


export { register,init }