Bring back the printer selection dialog for networked printers

plugins/UM3NetworkPrinting/src/Network/LocalClusterOutputDevice.py

@@ -1,16 +1,17 @@
 # Copyright (c) 2019 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
-
+import os
 from typing import Optional, Dict, List, Callable, Any
 
 from PyQt5.QtGui import QDesktopServices
-from PyQt5.QtCore import pyqtSlot, QUrl, pyqtSignal, pyqtProperty
+from PyQt5.QtCore import pyqtSlot, QUrl, pyqtSignal, pyqtProperty, QObject
 from PyQt5.QtNetwork import QNetworkReply
 
 from UM.FileHandler.FileHandler import FileHandler
 from UM.i18n import i18nCatalog
 from UM.Logger import Logger
 from UM.Scene.SceneNode import SceneNode
+from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.NetworkedPrinterOutputDevice import AuthState
 from cura.PrinterOutput.PrinterOutputDevice import ConnectionType
 
@@ -42,6 +43,8 @@ class LocalClusterOutputDevice(UltimakerNetworkedPrinterOutputDevice):
         )
 
         self._cluster_api = None  # type: Optional[ClusterApiClient]
+        self._active_exported_job = None  # type: Optional[ExportFileJob]
+        self._printer_select_dialog = None  # type: Optional[QObject]
 
         # We don't have authentication over local networking, so we're always authenticated.
         self.setAuthenticationState(AuthState.Authenticated)
@@ -129,17 +132,49 @@ class LocalClusterOutputDevice(UltimakerNetworkedPrinterOutputDevice):
         job.finished.connect(self._onPrintJobCreated)
         job.start()
 
+    ## Allows the user to choose a printer to print with from the printer selection dialogue.
+    #  \param unique_name: The unique name of the printer to target.
+    @pyqtSlot(str, name="selectTargetPrinter")
+    def selectTargetPrinter(self, unique_name: str = "") -> None:
+        self._startPrintJobUpload(unique_name if unique_name != "" else None)
+
     ## Handler for when the print job was created locally.
     #  It can now be sent over the network.
     def _onPrintJobCreated(self, job: ExportFileJob) -> None:
+        self._active_exported_job = job
+        # TODO: add preference to enable/disable this feature?
+        if self.clusterSize > 1:
+            self._showPrinterSelectionDialog()  # self._startPrintJobUpload will be triggered from this dialog
+            return
+        self._startPrintJobUpload()
+
+    ## Shows a dialog allowing the user to select which printer in a group to send a job to.
+    def _showPrinterSelectionDialog(self) -> None:
+        if not self._printer_select_dialog:
+            path = os.path.join(CuraApplication.getInstance().getPluginRegistry().getPluginPath("UM3NetworkPrinting"),
+                                "resources", "qml", "PrintWindow.qml")
+            self._printer_select_dialog = CuraApplication.getInstance().createQmlComponent(path, {"OutputDevice": self})
+        self._printer_select_dialog.show()
+
+    ## Upload the print job to the group.
+    def _startPrintJobUpload(self, unique_name: str = None) -> None:
+        if not self._active_exported_job:
+            Logger.log("e", "No active exported job to upload!")
+            return
         self._progress.show()
         parts = [
             self._createFormPart("name=owner", bytes(self._getUserName(), "utf-8"), "text/plain"),
-            self._createFormPart("name=\"file\"; filename=\"%s\"" % job.getFileName(), job.getOutput())
+            self._createFormPart("name=\"file\"; filename=\"%s\"" % self._active_exported_job.getFileName(),
+                                 self._active_exported_job.getOutput())
         ]
+        # If a specific printer was selected we include the name in the request.
+        # FIXME: Connect should allow the printer UUID here instead of the 'unique_name'.
+        if unique_name is not None:
+            parts.append(self._createFormPart("name=require_printer_name", bytes(unique_name, "utf-8"), "text/plain"))
         # FIXME: move form posting to API client
         self.postFormWithParts("/cluster-api/v1/print_jobs/", parts, on_finished=self._onPrintUploadCompleted,
                                on_progress=self._onPrintJobUploadProgress)
+        self._active_exported_job = None
 
     ## Handler for print job upload progress.
     def _onPrintJobUploadProgress(self, bytes_sent: int, bytes_total: int) -> None: