scuffed config screen

src/main/kotlin/moe/nea/notenoughupdates/util/ConfigHolder.kt

@@ -0,0 +1,117 @@
+package moe.nea.notenoughupdates.util
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.SerializationException
+import moe.nea.notenoughupdates.NotEnoughUpdates
+import moe.nea.notenoughupdates.events.NEUScreenEvents
+import net.minecraft.client.Minecraft
+import net.minecraft.commands.CommandSource
+import net.minecraft.network.chat.Component
+import java.io.IOException
+import java.nio.file.Path
+import java.util.concurrent.CopyOnWriteArrayList
+import kotlin.io.path.exists
+import kotlin.io.path.readText
+import kotlin.io.path.writeText
+import kotlin.reflect.KClass
+
+abstract class ConfigHolder<T>(val serializer: KSerializer<T>,
+                               val name: String,
+                               val default: () -> T) {
+
+    var config: T
+        private set
+
+    init {
+        config = readValueOrDefault()
+        putConfig(this::class, this)
+    }
+
+    val file: Path get() = NotEnoughUpdates.CONFIG_DIR.resolve("$name.json")
+
+    protected fun readValueOrDefault(): T {
+        if (file.exists())
+            try {
+                return NotEnoughUpdates.json.decodeFromString(
+                        serializer,
+                        file.readText()
+                )
+            } catch (e: IOException) {
+                badLoads.add(name)
+                NotEnoughUpdates.logger.error("IO exception during loading of config file $name. This will reset this config.", e)
+            } catch (e: SerializationException) {
+                badLoads.add(name)
+                NotEnoughUpdates.logger.error("Serialization exception during loading of config file $name. This will reset this config.", e)
+            }
+        return default()
+    }
+
+    private fun writeValue(t: T) {
+        file.writeText(NotEnoughUpdates.json.encodeToString(serializer, t))
+    }
+
+    fun save() {
+        writeValue(config)
+    }
+
+    fun load() {
+        config = readValueOrDefault()
+    }
+
+    fun markDirty() {
+        Companion.markDirty(this::class)
+    }
+
+    companion object {
+        private var badLoads: MutableList<String> = CopyOnWriteArrayList()
+        private val allConfigs: MutableMap<KClass<out ConfigHolder<*>>, ConfigHolder<*>> = mutableMapOf()
+        private val dirty: MutableSet<KClass<out ConfigHolder<*>>> = mutableSetOf()
+
+        private fun <T : ConfigHolder<K>, K> putConfig(kClass: KClass<T>, inst: ConfigHolder<K>) {
+            allConfigs[kClass] = inst
+        }
+
+        fun <T : ConfigHolder<K>, K> markDirty(kClass: KClass<T>) {
+            if (kClass !in allConfigs) {
+                NotEnoughUpdates.logger.error("Tried to markDirty '${kClass.qualifiedName}', which isn't registered as 'ConfigHolder'")
+                return
+            }
+            dirty.add(kClass)
+        }
+
+        private fun performSaves() {
+            val toSave = dirty.toList().also {
+                dirty.clear()
+            }
+            for (it in toSave) {
+                val obj = allConfigs[it]
+                if (obj == null) {
+                    NotEnoughUpdates.logger.error("Tried to save '${it}', which isn't registered as 'ConfigHolder'")
+                    continue
+                }
+                obj.save()
+            }
+        }
+
+        private fun warnForResetConfigs(player: CommandSource) {
+            if (badLoads.isNotEmpty()) {
+                player.sendSystemMessage(Component.literal("The following configs have been reset: ${badLoads.joinToString(", ")}. " +
+                        "This can be intentional, but probably isn't."))
+                badLoads.clear()
+            }
+        }
+
+        fun registerEvents() {
+            NEUScreenEvents.SCREEN_OPEN.register(NEUScreenEvents.OnScreenOpen { old, new ->
+                performSaves()
+                val p = Minecraft.getInstance().player
+                if (p != null) {
+                    warnForResetConfigs(p)
+                }
+                false
+            })
+        }
+
+
+    }
+}