pimatic-dewpoint

module.exports = (env) -> Promise = env.require 'bluebird' assert = env.require 'cassert' types = env.require('decl-api').types _ = env.require 'lodash' class DewPointPlugin extends env.plugins.Plugin init: (app, @framework, @config) => deviceConfigDef = require("./device-config-schema") @framework.deviceManager.registerDeviceClass("DewPointDevice", { configDef: deviceConfigDef.DewPointDevice, createCallback: (config, lastState) => return new DewPointDevice(config, lastState) }) plugin = new DewPointPlugin class DewPointDevice extends env.devices.Device temperature: 0.0 humidity: 0.0 dewPoint: 0.0 absHumidity: 0.0 windSpeed: 0.0 windChill: 0.0 heatIndex: 0.0 apparentTemperature: 0.0 attributes: temperature: description: "Temperature" type: types.number unit: "°C" acronym: 'T' humidity: description: "Relative Humidity" type: types.number unit: "%" acronym: 'RH' dewPoint: description: "Dew Point Temperature" type: types.number unit: "°C" acronym: 'DT' absHumidity: description: "Absolute Humidity" type: types.number unit: "g/m³" acronym: "AH" windSpeed: description: "Windspeed" type: types.number unit: "km/h" acronym: 'WS' windChill: description: "Windchill Temperature" type: types.number unit: "°C" acronym: 'WCT' heatIndex: description: "Heat Index Temperature" type: types.number unit: "°C" acronym: 'HIT' apparentTemperature: description: "Apparent Temperature" type: types.number unit: "°C" acronym: 'AT' constructor: (@config, lastState) -> @id = @config.id @name = @config.name @temperature = lastState?.temperature?.value or 0.0 @humidity = lastState?.humidity?.value or 0.0 @dewPoint = lastState?.dewPoint?.value or 0.0 @absHumidity = lastState?.absHumidity?.value or 0.0 @windSpeed = lastState?.windSpeed?.value or 0.0 @windChill = lastState?.windChill?.value or 0.0 @heatIndex = lastState?.heatIndex?.value or 0.0 @apparentTemperature = lastState?.apparentTemperature?.value or 0.0 @units = @config.units @attributes = _.cloneDeep @attributes if @units is "imperial" @attributes["temperature"].unit = '°F' @attributes["dewPoint"].unit = '°F' @attributes["windChill"].unit = '°F' @attributes["heatIndex"].unit = '°F' @attributes["apparentTemperature"].unit = '°F' else if @units is "standard" @attributes["temperature"].unit = 'K' @attributes["dewPoint"].unit = 'K' @attributes["windChill"].unit = 'K' @attributes["heatIndex"].unit = 'K' @attributes["apparentTemperature"].unit = 'K' @windUnits = @config.windUnits @attributes["windSpeed"].unit = @windUnits @varManager = plugin.framework.variableManager #so you get the variableManager @_exprChangeListeners = [] for reference in [ {name: "temperature", expression: @config.temperatureRef}, {name: "humidity", expression: @config.humidityRef} {name: "windSpeed", expression: @config.windSpeedRef} ] do (reference) => name = reference.name info = null evaluate = ( => # wait till VariableManager is ready return Promise.delay(10).then( => unless info? info = @varManager.parseVariableExpression(reference.expression) @varManager.notifyOnChange(info.tokens, evaluate) @_exprChangeListeners.push evaluate switch info.datatype when "numeric" then @varManager.evaluateNumericExpression(info.tokens) when "string" then @varManager.evaluateStringExpression(info.tokens) else assert false ).then((val) => if val env.logger.debug name, val @_setAttribute name, val @calcValues() return @[name] ) ) @_createGetter(name, evaluate) super() destroy: () -> @varManager.cancelNotifyOnChange(cl) for cl in @_exprChangeListeners super() calcHeatIndex: (t, rh, dp) -> if t < 27 or rh < 40 or dp < 12 t else c1 = -8.784695 c2 = 1.61139411 c3 = 2.338549 c4 = -0.14611605 c5 = -1.2308094 * 0.01 c6 = -1.6424828 * 0.01 c7 = 2.211732 * 0.001 c8 = 7.2546 * 0.0001 c9 = -3.582 * 0.000001 prh = rh * rh pt = t * t c1 + c2*t + c3*rh + c4*t*rh + c5*pt + c6*prh + c7*pt*rh + c8*t*prh + c9*pt*prh calcWindChill: (t, vw) -> if t >= 10 t else if vw >= 4.8 and vw <= 177 13.12 + 0.6215 * t + (0.3965 * t - 11.37) * Math.pow(vw, 0.16) else if vw < 4.8 t + 0.2 * (0.1345 * t - 1.59) * vw else t calcValues: -> t = @_fromUnitTemperature(@temperature) # dewPoint if t >= 0 a = 7.5 b = 237.3 else a = 7.6 b = 240.7 sdd = 6.1078 * Math.pow(10, (a * t) / (b + t)) dd = sdd * (@humidity / 100) v = Math.log(dd / 6.1078) / Math.log(10) td = (b * v) / (a - v) env.logger.debug 'dewPoint', @_toUnitTemperature(td) @_setAttribute 'dewPoint', @_toUnitTemperature(td) # absHumidity ah = 2.16679 * ((100 * dd) / (273.15 + t)) env.logger.debug 'absHumidity', ah @_setAttribute 'absHumidity', ah # windChill vw = @_fromUnitWindSpeed(@windSpeed) wct = @calcWindChill t, vw env.logger.debug 'windChill', @_toUnitTemperature(wct) @_setAttribute 'windChill', @_toUnitTemperature(wct) # heatIndex hit = @calcHeatIndex(t, @humidity, td) env.logger.debug 'heatIndex', @_toUnitTemperature(hit) @_setAttribute 'heatIndex', @_toUnitTemperature(hit) # apparentTemperature at = if t < 10 then vw else hit env.logger.debug 'apparentTemperature', @_toUnitTemperature(at) @_setAttribute 'apparentTemperature', @_toUnitTemperature(at) _setAttribute: (attributeName, value) -> @[attributeName] = value @emit attributeName, value _fromUnitTemperature: (t) -> if @units is "imperial" return @_fahrenheitToCelsius t else if @units is "standard" return @_kelvinToCelsius t else return t _toUnitTemperature: (t) -> if @units is "imperial" return @_celsiusToFahrenheit t else if @units is "standard" return @_celsiusToKelvin t else return t _fromUnitWindSpeed: (vw) -> if @windUnits is "mp/h" return @_milesToKm vw else if @windUnits is "m/s" return @_msToKm vw else if @windUnits is "ft/s" return @_ftsToKm vw else if @windUnits is "knots" return @_knotsToKm vw else return vw _fahrenheitToCelsius: (fahrenheit) -> return (fahrenheit - 32) * 5 / 9 _celsiusToFahrenheit: (celsius) -> return celsius * 9 / 5 + 32 _kelvinToCelsius: (kelvin) -> return kelvin - 273.15 _celsiusToKelvin: (celsius) -> return celsius + 273.15 _milesToKm: (miles) -> return (miles * 1.60934) _msToKm: (ms) -> return (ms * 3.6) _ftsToKm: (fts) -> return (fts * 1.09728) _knotsToKm: (knots) -> return (knots * 1.852) # getters for temperature & humidity are created by the constructor using @_createGetter method getDewPoint: -> Promise.resolve(@dewPoint) getAbsHumidity: -> Promise.resolve(@absHumidity) getWindChill: -> Promise.resolve(@windChill) getHeatIndex: -> Promise.resolve(@heatIndex) getApparentTemperature: -> Promise.resolve(@apparentTemperature) return plugin