Store default pre-heat time in central location

Its default is 900s or 15 minutes. QML now requests the time-out time and sends it on to the printer.

Contributes to issue CURA-3161.

cura/PrinterOutputDevice.py

@@ -45,6 +45,7 @@ class PrinterOutputDevice(QObject, OutputDevice):
         self._job_name = ""
         self._error_text = ""
         self._accepts_commands = True
+        self._preheat_bed_timeout = 900 #Default time-out for pre-heating the bed, in seconds.
 
         self._printer_state = ""
         self._printer_type = "unknown"
@@ -199,6 +200,11 @@ class PrinterOutputDevice(QObject, OutputDevice):
             self._target_bed_temperature = temperature
             self.targetBedTemperatureChanged.emit()
 
+    ##
+    @pyqtProperty(int)
+    def preheatBedTimeout(self):
+        return self._preheat_bed_timeout
+
     ## Time the print has been printing.
     #  Note that timeTotal - timeElapsed should give time remaining.
     @pyqtProperty(float, notify = timeElapsedChanged)

plugins/UM3NetworkPrinting/NetworkPrinterOutputDevice.py

@@ -248,7 +248,7 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
     #   \param duration How long the bed should stay warm, in seconds. Defaults
     #   to a quarter hour.
     @pyqtSlot(int, int)
-    def preheatBed(self, temperature, duration=900):
+    def preheatBed(self, temperature, duration):
         url = QUrl("http://" + self._address + self._api_prefix + "printer/bed/pre_heat")
         data = """{"temperature": "%i", "timeout": "%i"}""" % (temperature, duration)
         put_request = QNetworkRequest(url)
@@ -260,7 +260,7 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
     #   If the bed is not pre-heated, nothing happens.
     @pyqtSlot()
     def cancelPreheatBed(self):
-        self.preheatBed(temperature=0)
+        self.preheatBed(temperature = 0, duration = 0)
 
     ##  Changes the target bed temperature and makes sure that its signal is
     #   emitted.

resources/qml/PrintMonitor.qml

@@ -404,7 +404,7 @@ Column
                 connectedPrinter.preheatBed(preheatTemperatureInput.text, 900);
                 var now = new Date();
                 var end_time = new Date();
-                end_time.setTime(now.getTime() + 900 * 1000); //*1000 because time is in milliseconds here.
+                end_time.setTime(now.getTime() + connectedPrinter.preheatBedTimeout * 1000); //*1000 because time is in milliseconds here.
                 preheatCountdownTimer.endTime = end_time;
                 preheatCountdownTimer.start();
                 preheatCountdownTimer.update(); //Update once before the first timer is triggered.