Translucent translation of machine instances

Machine instances are translucently translated from version 1 to version 2. No setting changes are applied yet, nor has the format itself changed.

Contributes to issue CURA-844.

plugins/VersionUpgrade/VersionUpgrade21to22/MachineInstance.py

@@ -1,6 +1,11 @@
 # Copyright (c) 2015 Ultimaker B.V.
 # Cura is released under the terms of the AGPLv3 or higher.
 
+import UM.SettingsError #To indicate that a file is of incorrect format.
+
+import configparser #To read config files.
+import io #To write config files to strings as if they were files.
+
 ##  Creates a new machine instance instance by parsing a serialised machine
 #   instance in version 1 of the file format.
 #
@@ -8,14 +13,66 @@
 #   \return A machine instance instance, or None if the file format is
 #   incorrect.
 def importVersion1(serialised):
-    return None #Not implemented yet.
+    return MachineInstance(serialised)
 
 ##  A representation of a machine instance used as intermediary form for
 #   conversion from one format to the other.
 class MachineInstance:
+    ##  Reads version 1 of the file format, storing it in memory.
+    #
+    #   \param serialised A string with the contents of a machine instance file.
+    def __init__(self, serialised):
+        config = configparser.ConfigParser(interpolation = None)
+        config.read_string(serialised) #Read the input string as config file.
+
+        #Checking file correctness.
+        if not config.has_section("general"):
+            raise SettingsError.InvalidFormatError("general")
+        if not config.has_option("general", "version"):
+            raise SettingsError.InvalidFormatError("general/version")
+        if not config.has_option("general", "name"):
+            raise SettingsError.InvalidFormatError("general/name")
+        if not config.has_option("general", "type"):
+            raise SettingsError.InvalidFormatError("general/type")
+        if int(config.get("general", "version")) != 1: #Explicitly hard-code version 1, since if this number changes the programmer MUST change this entire function.
+            raise SettingsError.InvalidVersionError("Version upgrade intermediary version 1")
+
+        self._type_name = config.get("general", "type")
+        self._variant_name = config.get("general", "variant", fallback = None)
+        self._name = config.get("general", "name")
+        self._key = config.get("general", "key", fallback = None)
+        self._active_profile_name = config.get("general", "active_profile", fallback = None)
+        self._active_material_name = config.get("general", "material", fallback = None)
+
+        self._machine_setting_overrides = {}
+        for key, value in config["machine_settings"].items():
+            self._machine_setting_overrides[key] = value
+
     ##  Serialises this machine instance as file format version 2.
     #
     #   \return A serialised form of this machine instance, serialised in
     #   version 2 of the file format.
     def exportVersion2():
-        raise Exception("Not implemented yet.")
+        config = configparser.ConfigParser(interpolation = None) #Build a config file in the form of version 2.
+
+        config.add_section("general")
+        config.set("general", "name", self._name)
+        config.set("general", "type", self._type_name)
+        config.set("general", "version", 2) #Hard-code version 2, since if this number changes the programmer MUST change this entire function.
+        if self._variant_name:
+            config.set("general", "variant", self._variant_name)
+        if self._key:
+            config.set("general", "key", self._key)
+        if self._active_profile_name:
+            config.set("general", "active_profile", self._active_profile_name)
+        if self._active_material_name:
+            config.set("general", "material", self._active_material_name)
+
+        config.add_section("machine_settings")
+        for key, value in self._machine_setting_overrides.items():
+            #TODO: Filter these through a translation dictionary.
+            config.set("machine_settings", key, value)
+
+        output = io.StringIO()
+        config.write(output)
+        return output.getvalue()