Save the Snowy configuration at exit

common/src/main/kotlin/fr/username404/snowygui/config/Configuration.kt

@@ -3,6 +3,7 @@ package fr.username404.snowygui.config
 import com.typesafe.config.Config
 import com.typesafe.config.ConfigException
 import com.typesafe.config.ConfigFactory
+import com.typesafe.config.ConfigRenderOptions
 import fr.username404.snowygui.Snowy
 import net.minecraft.client.Minecraft
 import java.io.File
@@ -14,6 +15,7 @@ object Configuration {
         |  displayInitMessage = true
         |}
     """.trimMargin()
+    private val baseConf = ConfigFactory.parseString(base)
     @JvmField
     val obtained: Config = run {
         lateinit var result: Config
@@ -26,10 +28,29 @@ object Configuration {
             }; result = try {
                 ConfigFactory.parseFile(file)
             } catch (e: ConfigException) {
-                Snowy.logs.warn("Could not parse the snowy configuration file, the default configuration will be used instead.")
+                Snowy.logs.warn("Could not parse the snowy configuration file, the default configuration will be used instead."); baseConf
-                ConfigFactory.parseString(base)
             }
         }
-        ConfigFactory.load(result).getConfig("Snowy")
+        ConfigFactory.load(result).getConfig("Snowy").resolveWith(baseConf)
+    }
+    init {
+        Runtime.getRuntime().addShutdownHook(
+            Thread {
+                file.writeText(
+                    """
+                        Snowy {
+                          ${
+                              obtained.root().render(
+                                  ConfigRenderOptions.defaults()
+                                      .setFormatted(true)
+                                      .setJson(false)
+                                      .setOriginComments(false)
+                              ).trimEnd()
+                          }
+                        }
+                    """.trimIndent()
+                )
+            }
+        )
     }
 }