From bbf38e5db13e92b4570753d6b3f7f212e750d977 Mon Sep 17 00:00:00 2001
From: Sam Stenvall <sam.stenvall@nitor.com>
Date: Fri, 13 Oct 2023 10:49:33 +0300
Subject: [PATCH] Add support for Shelly Pro 3EM (Gen2 EM devices in general)

Closes #10

Still need to implement characteristics for these
---
 src/sensor.ts |  4 ++++
 src/shelly.ts | 42 ++++++++++++++++++++++++++++++++++++++----
 2 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/src/sensor.ts b/src/sensor.ts
index c380e62..5d3f034 100644
--- a/src/sensor.ts
+++ b/src/sensor.ts
@@ -11,6 +11,7 @@ export enum SensorType {
 export enum ShellyType {
   Gen1 = 'gen1',
   Gen2PM = 'gen2-pm',
+  Gen2EM = 'gen2-em',
 }
 
 export enum CharacteristicsSensorType {
@@ -46,7 +47,10 @@ export interface IotawattCharacteristicsSensor extends CharacteristicsSensor {
 interface ShellySensorSettings {
   address: string
   type: undefined | ShellyType
+  // For Gen1 devices and Gen2 devices implementing the "Switch" component
   meter: number
+  // For devices implementing the "EM" component
+  phase: string | undefined
 }
 
 export interface ShellySensor extends PowerSensor {
diff --git a/src/shelly.ts b/src/shelly.ts
index d5680e4..ac8093a 100644
--- a/src/shelly.ts
+++ b/src/shelly.ts
@@ -11,20 +11,28 @@ type Gen1StatusResult = {
   meters: Gen1MeterResult[]
 }
 
-type Gen2GetStatusResult = {
+type Gen2SwitchGetStatusResult = {
   apower: number
 }
 
+type Gen2EMGetStatusResult = {
+  a_act_power: number
+  b_act_power: number
+  c_act_power: number
+}
+
 const getSensorDataUrl = (sensor: ShellySensor): string => {
   const address = sensor.shelly.address
   const meter = sensor.shelly.meter
 
   // Request a different endpoint depending on what type of Shelly we're dealing with
   switch (sensor.shelly.type as ShellyType) {
-    case ShellyType.Gen2PM:
-      return `http://${address}/rpc/Switch.GetStatus?id=${meter}`
     case ShellyType.Gen1:
       return `http://${address}/status`
+    case ShellyType.Gen2PM:
+      return `http://${address}/rpc/Switch.GetStatus?id=${meter}`
+    case ShellyType.Gen2EM:
+      return `http://${address}/rpc/EM.GetStatus?id=${meter}`
   }
 }
 
@@ -40,7 +48,7 @@ const parseGen1Response = (timestamp: number, circuit: Circuit, httpResponse: Ax
 }
 
 const parseGen2PMResponse = (timestamp: number, circuit: Circuit, httpResponse: AxiosResponse): PowerSensorData => {
-  const data = httpResponse.data as Gen2GetStatusResult
+  const data = httpResponse.data as Gen2SwitchGetStatusResult
 
   return {
     timestamp: timestamp,
@@ -49,6 +57,30 @@ const parseGen2PMResponse = (timestamp: number, circuit: Circuit, httpResponse:
   }
 }
 
+const parseGen2EMResponse = (timestamp: number, circuit: Circuit, httpResponse: AxiosResponse): PowerSensorData => {
+  const sensor = circuit.sensor as ShellySensor
+  const data = httpResponse.data as Gen2EMGetStatusResult
+
+  let watts = 0
+  switch (sensor.shelly.phase) {
+    case 'a':
+      watts = data.a_act_power
+      break
+    case 'b':
+      watts = data.b_act_power
+      break
+    case 'c':
+      watts = data.c_act_power
+      break
+  }
+
+  return {
+    timestamp: timestamp,
+    circuit: circuit,
+    watts: watts,
+  }
+}
+
 export const getSensorData: PowerSensorPollFunction = async (
   timestamp: number,
   circuit: Circuit,
@@ -65,6 +97,8 @@ export const getSensorData: PowerSensorPollFunction = async (
         return parseGen1Response(timestamp, circuit, httpResponse)
       case ShellyType.Gen2PM:
         return parseGen2PMResponse(timestamp, circuit, httpResponse)
+      case ShellyType.Gen2EM:
+        return parseGen2EMResponse(timestamp, circuit, httpResponse)
     }
   } catch (e) {
     console.error((e as Error).message)