homebridge-wemo/lib/device/coffee.js

Homebridge plugin to integrate Wemo devices into HomeKit.

import { Builder, parseStringPromise } from 'xml2js'

import { decodeXML, parseError } from '../utils/functions.js'
import platformLang from '../utils/lang-en.js'

export default class {
  constructor(platform, accessory) {
    // Set up variables from the platform
    this.hapChar = platform.api.hap.Characteristic
    this.hapErr = platform.api.hap.HapStatusError
    this.hapServ = platform.api.hap.Service
    this.platform = platform

    // Set up variables from the accessory
    this.accessory = accessory

    // Add the switch service if it doesn't already exist
    this.service = this.accessory.getService(this.hapServ.Switch)
      || this.accessory.addService(this.hapServ.Switch)

    // Add the set handler to the outlet on/off characteristic
    this.service
      .getCharacteristic(this.hapChar.On)
      .removeOnSet()
      .onSet(async value => this.internalModeUpdate(value))

    // Output the customised options to the log
    const opts = JSON.stringify({
    })
    platform.log('[%s] %s %s.', accessory.displayName, platformLang.devInitOpts, opts)

    // Request a device update immediately
    this.requestDeviceUpdate()

    // Start a polling interval if the user has disabled upnp
    if (this.accessory.context.connection === 'http') {
      this.pollingInterval = setInterval(
        () => this.requestDeviceUpdate(),
        platform.config.pollingInterval * 1000,
      )
    }
  }

  receiveDeviceUpdate(attribute) {
    // Log the receiving update if debug is enabled
    this.accessory.logDebug(`${platformLang.recUpd} [${attribute.name}: ${JSON.stringify(attribute.value)}]`)

    // Check which attribute we are getting
    switch (attribute.name) {
      case 'Mode':
        this.externalModeUpdate(attribute.value)
        break
      default:
    }
  }

  async sendDeviceUpdate(attributes) {
    // Log the sending update if debug is enabled
    this.accessory.log(`${platformLang.senUpd} ${JSON.stringify(attributes)}`)

    // Generate the XML to send
    const builder = new Builder({
      rootName: 'attribute',
      headless: true,
      renderOpts: { pretty: false },
    })
    const xmlAttributes = Object.keys(attributes)
      .map(attributeKey => builder.buildObject({
        name: attributeKey,
        value: attributes[attributeKey],
      }))
      .join('')

    // Send the update
    await this.platform.httpClient.sendDeviceUpdate(
      this.accessory,
      'urn:Belkin:service:deviceevent:1',
      'SetAttributes',
      {
        attributeList: { '#text': xmlAttributes },
      },
    )
  }

  async requestDeviceUpdate() {
    try {
      // Request the update
      const data = await this.platform.httpClient.sendDeviceUpdate(
        this.accessory,
        'urn:Belkin:service:deviceevent:1',
        'GetAttributes',
      )

      // Parse the response
      const decoded = decodeXML(data.attributeList)
      const xml = `<attributeList>${decoded}</attributeList>`
      const result = await parseStringPromise(xml, { explicitArray: false })
      Object.keys(result.attributeList.attribute).forEach((key) => {
        // Only send the required attributes to the receiveDeviceUpdate function
        switch (result.attributeList.attribute[key].name) {
          case 'Mode':
            this.receiveDeviceUpdate({
              name: result.attributeList.attribute[key].name,
              value: Number.parseInt(result.attributeList.attribute[key].value, 10),
            })
            break
          default:
        }
      })
    } catch (err) {
      const eText = parseError(err, [
        platformLang.timeout,
        platformLang.timeoutUnreach,
        platformLang.noService,
      ])
      this.accessory.logDebugWarn(`${platformLang.rduErr} ${eText}`)
    }
  }

  async internalModeUpdate(value) {
    try {
      // Coffee maker cannot be turned off remotely
      if (!value) {
        throw new Error('coffee maker cannot be turned off remotely')
      }

      // Send the update to turn ON
      await this.sendDeviceUpdate({ Mode: 4 })

      // Update the cache value and log the change if appropriate
      this.cacheState = true
      this.accessory.log(`${platformLang.curState} [on]`)
    } catch (err) {
      // Catch any errors
      const eText = parseError(err, [platformLang.timeout, platformLang.timeoutUnreach])
      this.accessory.logWarn(`${platformLang.cantCtl} ${eText}`)

      // Throw a 'no response' error and set a timeout to revert this after 2 seconds
      setTimeout(() => {
        this.service.updateCharacteristic(this.hapChar.On, this.cacheState)
      }, 2000)
      throw new this.hapErr(-70402)
    }
  }

  externalModeUpdate(value) {
    try {
      // Value of 4 means brewing (ON) otherwise (OFF)
      value = value === 4

      // Check to see if the cache value is different
      if (value === this.cacheState) {
        return
      }

      // Update the HomeKit characteristics
      this.service.updateCharacteristic(this.hapChar.On, value)

      // Update the cache value and log the change if appropriate
      this.cacheState = value
      this.accessory.log(`${platformLang.curState} [${value ? 'on' : 'off'}]`)
    } catch (err) {
      // Catch any errors
      this.accessory.logWarn(`${platformLang.cantUpd} ${parseError(err)}`)
    }
  }
}