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+# OpenHab integration using `exec` binding
+
+## generate `token.json`
+
+TODO
+
+## Define Shutters including Alexa integration
+
+```
+// South
+Group:Rollershutter:AVG gShuttersSouth
+  "Rollläden Süd [%d%%]"
+  <rollershutter>
+  (gshutters)
+  ["OpenLevel", "Blinds"]
+  {alexa="PercentageController.percentage" [category="SWITCH"]}
+
+// Office
+Group:Rollershutter:AVG gShuttersOffice
+  "Rollläden Büro [%d%%]"
+  <rollershutter>
+  (Office, gshutters)
+  ["OpenLevel", "Blinds"]
+  {alexa="PercentageController.percentage" [category="SWITCH"]}
+Rollershutter OfficeLeft_Rollershutter
+  "Rollladen Büro Links [%d%%]"
+  (Office, gshutters, gShuttersOffice, gShuttersSouth)
+  ["OpenLevel", "Blinds"]
+  {alexa="PercentageController.percentage" [category="SWITCH"]}
+Rollershutter OfficeRight_Rollershutter
+  "Rollladen Büro Rechts [%d%%]"
+  (Office, gshutters, gShuttersOffice, gShuttersSouth)
+  ["OpenLevel", "Blinds"]
+  {alexa="PercentageController.percentage" [category="SWITCH"]}
+```
+
+## Update item state
+
+## file `things/velux.things`
+
+```
+Thing exec:command:velux [command="/openhab/conf/velux-cli dump -outfile - -tokenfile /openhab/conf/token.json", interval=30, timeout=20]
+```
+
+### file `items/trigger.items`
+
+```
+String VeluxExec "velux status update" {channel="exec:command:velux:output"}
+```
+
+### file `rules/velux.rules`
+
+```
+val mapRollerShutterState = [ String veluxName, String state |
+  100-Integer::parseInt(transform("JSONPATH", "$.ShutterStatus['" + veluxName + "']", state))
+]
+
+rule "velux item update"
+when
+   Item VeluxExec changed
+then
+  val jsonstate = triggeringItem.state.toString
+  logInfo("velux item update", jsonstate)
+
+  val temp = transform("JSONPATH", "$.Temperature.Bedroom", jsonstate)
+  VeluxBedroomTemperature.postUpdate(Integer::parseInt(temp)/10.0)
+
+  val co2 = transform("JSONPATH", "$.Co2.Bedroom", jsonstate)
+  VeluxBedroomCo2.postUpdate(Integer::parseInt(co2))
+
+  val humidity = transform("JSONPATH", "$.Humidity.Bedroom", jsonstate)
+  VeluxBedroomHumidity.postUpdate(Integer::parseInt(humidity))
+
+  val airQuality = transform("JSONPATH", "$.AirQuality.Bedroom", jsonstate)
+  VeluxBedroomAirQuality.postUpdate(Integer::parseInt(airQuality))
+
+  val lux = transform("JSONPATH", "$.Lux.Bedroom", jsonstate)
+  VeluxBedroomLux.postUpdate(Integer::parseInt(lux))
+
+  OfficeLeft_Rollershutter.postUpdate(mapRollerShutterState.apply("Büro links", jsonstate))
+  OfficeRight_Rollershutter.postUpdate(mapRollerShutterState.apply("Büro rechts", jsonstate))
+
+  # ...
+
+  LivingroomLeft_Rollershutter.postUpdate(mapRollerShutterState.apply("Wohnzimmer links", jsonstate))
+  LivingroomRight_Rollershutter.postUpdate(mapRollerShutterState.apply("Wohnzimmer rechts", jsonstate))
+
+  val batterySensor = transform("JSONPATH", "$.BatteryPercent['Sensor switch 1']", jsonstate)
+  VeluxSensor_BatteryLevel.postUpdate(Integer::parseInt(batterySensor))
+  if (Integer::parseInt(batterySensor) < 10) {
+    VeluxSensor_BatteryLow.postUpdate(ON)
+  } else {
+    VeluxSensor_BatteryLow.postUpdate(OFF)
+  }
+
+  val batteryDeparture = transform("JSONPATH", "$.BatteryPercent['Departure switch 1']", jsonstate)
+  VeluxDeparture_BatteryLevel.postUpdate(Integer::parseInt(batteryDeparture))
+  if (Integer::parseInt(batteryDeparture) < 10) {
+    VeluxDeparture_BatteryLow.postUpdate(ON)
+  } else {
+    VeluxDeparture_BatteryLow.postUpdate(OFF)
+  }
+end
+```
+
+
+
+## Control Shutters
+
+### file `rules/velux.rules`
+
+```
+val mapRollerShutterState = [ String veluxName, String state |
+  100-Integer::parseInt(transform("JSONPATH", "$.ShutterStatus['" + veluxName + "']", state))
+]
+
+rule "shutters command"
+when
+  Member of gshutters received command
+then
+  logInfo("shutters", triggeringItem.name + ": " + triggeringItem.state.toString + " - " + receivedCommand)
+
+  if (triggeringItem instanceof GroupItem) {
+    return
+  } else {
+    var int position
+    if (receivedCommand == UP) {
+      position = 100
+    } else if (receivedCommand == DOWN) {
+      position = 0
+    } else if (receivedCommand == STOP) {
+      position = 100
+    } else if (receivedCommand instanceof Number) {
+      position = 100 - receivedCommand.intValue
+    }
+
+    var String veluxShutter
+    switch (triggeringItem) {
+      case OfficeLeft_Rollershutter: veluxShutter = "Büro links"
+      case OfficeRight_Rollershutter: veluxShutter = "Büro rechts"
+
+      # ...
+
+      case LivingroomRight_Rollershutter: veluxShutter = "Wohnzimmer rechts"
+      case LivingroomLeft_Rollershutter: veluxShutter = "Wohnzimmer links"
+    }
+
+    logInfo("shutters",  "moving " + veluxShutter + " to " + position)
+
+    logInfo("shutters", "/openhab/conf/velux-cli@@moveShutters@@-tokenfile@@/openhab/conf/token.json@@-shutters@@" + veluxShutter + "@@-pos@@" + position, 1000)
+    val String Answer = executeCommandLine("/openhab/conf/velux-cli@@moveShutters@@-tokenfile@@/openhab/conf/token.json@@-shutters@@" + veluxShutter + "@@-pos@@" + position, 1000)
+    logInfo("shutters", "Result:" + Answer)
+  }
+end
+```
+
+## Usage in rules
+
+```
+var tempThreshold = 28|"℃"
+
+rule "Close south shutters to 50% at 8:30 when too warm"
+when
+  Time cron "0 30 8 ? * * *"
+then
+  if (gWeatherForecastTodayMaxTemperature.state >= tempThreshold) {
+    if (gShuttersSouth.state == 0) {
+      gShuttersSouth.sendCommand(50)
+    } else {
+      logInfo("shutters", "some shutters already down: " + gShuttersSouth.state)
+    }
+  } else {
+    logInfo("shutters", "keeping shutters open temperture below " + tempThreshold + ": " + gWeatherForecastTodayMaxTemperature.state)
+  }
+end
+
+rule "Open south shutters at 18:00"
+when
+  Time cron "0 0 18 ? * * *"
+then
+  if (gShuttersSouth.state == 50 || gShuttersSouth.state == 70) {
+    gShuttersSouth.sendCommand(0)
+  } else {
+    logInfo("shutters", "some shutters already down up: " + gShuttersSouth.state)
+  }
+end
+```