STAR-322: Extracting file handler methods

plugins/UM3NetworkPrinting/src/BaseCuraConnectDevice.py

@@ -1,8 +1,72 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
+from typing import Optional, Dict, Union
+
+from UM.FileHandler.FileHandler import FileHandler
+from UM.FileHandler.FileWriter import FileWriter
+from UM.Logger import Logger
+from UM.OutputDevice import OutputDeviceError  # To show that something went wrong when writing.
+from UM.Version import Version  # To check against firmware versions for support.
+from UM.i18n import i18nCatalog
+from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.NetworkedPrinterOutputDevice import NetworkedPrinterOutputDevice
 
 
-## this is the base class for the UM3 output devices (via connect or cloud)
+## Class that contains all the translations for this module.
+class T:
+    # The translation catalog for this device.
+
+    _I18N_CATALOG = i18nCatalog("cura")
+    NO_FORMATS_AVAILABLE = _I18N_CATALOG.i18nc("@info:status", "There are no file formats available to write with!")
+
+
+## This is the base class for the UM3 output devices (via connect or cloud)
 class BaseCuraConnectDevice(NetworkedPrinterOutputDevice):
-    pass
+
+    ## Gets the default file handler
+    @property
+    def defaultFileHandler(self) -> FileHandler:
+        return CuraApplication.getInstance().getMeshFileHandler()
+
+    ## Chooses the preferred file format for the given file handler.
+    #  \param file_handler: The file handler.
+    #  \return A dict with the file format details, with format:
+    #       {id: str, extension: str, description: str, mime_type: str, mode: int, hide_in_file_dialog: bool}
+    def _getPreferredFormat(self, file_handler: Optional[FileHandler]) -> Optional[Dict[str, Union[str, int, bool]]]:
+        # Formats supported by this application (file types that we can actually write).
+        application = CuraApplication.getInstance()
+
+        file_handler = file_handler or self.defaultFileHandler
+        file_formats = file_handler.getSupportedFileTypesWrite()
+
+        global_stack = application.getGlobalContainerStack()
+        # Create a list from the supported file formats string.
+        if not global_stack:
+            Logger.log("e", "Missing global stack!")
+            return
+
+        machine_file_formats = global_stack.getMetaDataEntry("file_formats").split(";")
+        machine_file_formats = [file_type.strip() for file_type in machine_file_formats]
+        # Exception for UM3 firmware version >=4.4: UFP is now supported and should be the preferred file format.
+        if "application/x-ufp" not in machine_file_formats and Version(self.firmwareVersion) >= Version("4.4"):
+            machine_file_formats = ["application/x-ufp"] + machine_file_formats
+
+        # Take the intersection between file_formats and machine_file_formats.
+        format_by_mimetype = {f["mime_type"]: f for f in file_formats}
+
+        # Keep them ordered according to the preference in machine_file_formats.
+        file_formats = [format_by_mimetype[mimetype] for mimetype in machine_file_formats]
+
+        if len(file_formats) == 0:
+            Logger.log("e", "There are no file formats available to write with!")
+            raise OutputDeviceError.WriteRequestFailedError(T.NO_FORMATS_AVAILABLE)
+        return file_formats[0]
+
+    ## Gets the file writer for the given file handler and mime type.
+    #  \param file_handler: The file handler.
+    #  \param mime_type: The mine type.
+    #  \return A file writer.
+    def _getWriter(self, file_handler: Optional[FileHandler], mime_type: str) -> Optional[FileWriter]:
+        # Just take the first file format available.
+        file_handler = file_handler or self.defaultFileHandler
+        return file_handler.getWriterByMimeType(mime_type)