Support for resetting to a default fan speed each time a fan is turne…

…d on (#503)

          "alwaysResetToDefaults": true,
          "defaultFanSpeed": 30,

accessories/fan.js

@@ -5,13 +5,33 @@ const SwitchAccessory = require('./switch');
 class FanAccessory extends SwitchAccessory {
 
   async setSwitchState (hexData, previousValue) {
+    const { config, state, serviceManager } = this;
+
     if (!this.state.switchState) {
       this.lastFanSpeed = undefined;
     }
 
+    // Reset the fan speed back to the default speed when turned off
+    if (this.state.switchState === false && config && config.alwaysResetToDefaults) {
+      this.setDefaults();
+      serviceManager.setCharacteristic(Characteristic.RotationSpeed, state.fanSpeed);
+    }
+
     super.setSwitchState(hexData, previousValue);
   }
 
+  setDefaults () {
+    super.setDefaults();
+
+    let { config, state } = this;
+
+    // Reset the fan speed back to the default speed when turned off
+    // This will also be called whenever homebridge is restarted
+    if (config && config.alwaysResetToDefaults) {
+      state.fanSpeed = (config.defaultFanSpeed !== undefined) ? config.defaultFanSpeed : 100;
+    }
+  }
+
   async setFanSpeed (hexData) {
     const { data, host, log, state, name, debug} = this;
 
@@ -30,7 +50,6 @@ class FanAccessory extends SwitchAccessory {
     })
 
     if (foundSpeeds.length === 0) {
-
       return log(`${name} setFanSpeed: No fan speed hex codes provided.`)
     }