save window location and resolution on shutdown

main.py

@@ -16,6 +16,8 @@ default_configuration = {
 # empty configuration by default because new values will be added while trying to load them
 # this allows the IDE to load old configuration files with missing keys
 configuration = {}
+home_directory = os.path.expanduser("~")
+config_file_path = os.path.join(home_directory, "some_ide_config.json")
 
 def info(message):
     # print info to sys.stderr because it isn’t really output, just debug information
@@ -52,6 +54,17 @@ def get_configuration_value(key):
             return None
     return configuration[key]
 
+def set_configuration_value(key, value, save_to_disk=True):
+    if not key in configuration:
+        info("Writing configuration for previously unknown key "+str(key)+".")
+    configuration[key]=value
+    try:
+        config_file = open(config_file_path, "w")
+        config_file.write(json.dumps(configuration))
+        config_file.close()
+    except:
+        error("Failed to save config file.")
+
 # easy way to get data out of window events
 class Window_Interaction_Handler:
     # constructor
@@ -107,8 +120,6 @@ class Window_Interaction_Handler:
 ################################################################################
 
 # read configuration
-home_directory = os.path.expanduser("~")
-config_file_path = os.path.join(home_directory, "some_ide_config.json")
 if os.path.isfile(config_file_path):
     try:
         config_file = open(config_file_path, "r")
@@ -241,4 +252,9 @@ def rebuild_menu():
 
 rebuild_menu()
 
+def handle_exit():
+    set_configuration_value("window geometry", main_window.geometry())
+    main_window.destroy()
+
+main_window.protocol("WM_DELETE_WINDOW", handle_exit)
 main_window.mainloop()