backport config annotations

src/main/java/com/falsepattern/lib/config/ConfigurationManager.java

@@ -0,0 +1,112 @@
+package com.falsepattern.lib.config;
+
+import cpw.mods.fml.client.event.ConfigChangedEvent;
+import cpw.mods.fml.common.eventhandler.SubscribeEvent;
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+import lombok.val;
+import lombok.var;
+import net.minecraft.launchwrapper.Launch;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.common.config.Configuration;
+import net.minecraftforge.common.config.Property;
+
+import java.nio.file.Path;
+import java.util.*;
+
+/**
+ * Class for controlling the loading of configuration files.
+ */
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public class ConfigurationManager {
+    private static final Map<String, Set<Class<?>>> configs = new HashMap<>();
+
+    private static final ConfigurationManager instance = new ConfigurationManager();
+
+    private static boolean initialized = false;
+
+    private static Path configDir;
+
+    /**
+     * Registers a configuration class to be loaded.
+     * @param config The class to register.
+     */
+    public static void registerConfig(Class<?> config) throws IllegalAccessException {
+        val cfg = Optional.of(config.getAnnotation(Config.class)).orElseThrow(() -> new IllegalArgumentException("Class " + config.getName() + " does not have a @Config annotation!"));
+        val cfgSet = configs.computeIfAbsent(cfg.modid(), (ignored) -> new HashSet<>());
+        cfgSet.add(config);
+        processConfig(config);
+    }
+
+    /**
+     * Internal, do not use.
+     */
+    public static void init() {
+        if (initialized) return;
+        configDir = Launch.minecraftHome.toPath().resolve("config");
+        MinecraftForge.EVENT_BUS.register(instance);
+        initialized = true;
+    }
+
+    /**
+     * Internal, do not use.
+     * @param event The event.
+     */
+    @SubscribeEvent
+    public void onConfigChanged(ConfigChangedEvent.OnConfigChangedEvent event) {
+        val configClasses = configs.get(event.modID);
+        if (configClasses == null)
+            return;
+        configClasses.forEach((config) -> {
+            try {
+                processConfig(config);
+            } catch (IllegalAccessException e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
+    private static void processConfig(Class<?> configClass) throws IllegalAccessException {
+        val cfg = configClass.getAnnotation(Config.class);
+        val category = cfg.category();
+        val rawConfig = new Configuration(configDir.resolve(cfg.name()).toFile());
+        val cat = rawConfig.getCategory(category);
+
+        for (val field: configClass.getDeclaredFields()) {
+            if (field.getAnnotation(Config.Ignore.class) != null) continue;
+            field.setAccessible(true);
+            val comment = Optional.of(field.getAnnotation(Config.Comment.class)).map(Config.Comment::value).map((lines) -> String.join("\n", lines)).orElse("");
+            val name = Optional.of(field.getAnnotation(Config.Name.class)).map(Config.Name::value).orElse(field.getName());
+            val langKey = Optional.of(field.getAnnotation(Config.LangKey.class)).map(Config.LangKey::value).orElse(name);
+            var boxed = false;
+            Property prop = cat.get(name);
+            prop.comment = comment;
+            prop.setLanguageKey(langKey);
+            if ((boxed = field.getType().equals(Integer.class)) || field.getType().equals(int.class)) {
+                val range = Optional.of(field.getAnnotation(Config.RangeInt.class));
+                prop.setMinValue(range.map(Config.RangeInt::min).orElse(Integer.MIN_VALUE));
+                prop.setMaxValue(range.map(Config.RangeInt::max).orElse(Integer.MAX_VALUE));
+                prop.setDefaultValue(Optional.of(field.getAnnotation(Config.DefaultInt.class)).map(Config.DefaultInt::value).orElse(boxed ? (Integer)field.get(null) : field.getInt(null)));
+                field.setInt(null, prop.getInt());
+            } else if ((boxed = field.getType().equals(Double.class)) || field.getType().equals(double.class)) {
+                val range = Optional.of(field.getAnnotation(Config.RangeDouble.class));
+                prop.setMinValue(range.map(Config.RangeDouble::min).orElse(Double.MIN_VALUE));
+                prop.setMaxValue(range.map(Config.RangeDouble::max).orElse(Double.MAX_VALUE));
+                prop.setDefaultValue(Optional.of(field.getAnnotation(Config.DefaultDouble.class)).map(Config.DefaultDouble::value).orElse(boxed ? (Double) field.get(null) : field.getDouble(null)));
+                field.setDouble(null, prop.getDouble());
+            } else if ((boxed = field.getType().equals(Boolean.class)) || field.getType().equals(boolean.class)) {
+                prop.setDefaultValue(boxed ? (Boolean)field.get(null) : field.getBoolean(null));
+                field.setBoolean(null, prop.getBoolean());
+            } else if (field.getType().equals(String.class)) {
+                prop.setDefaultValue((String)field.get(null));
+                field.set(null, prop.getString());
+            }
+            if (field.isAnnotationPresent(Config.RequiresMcRestart.class)) {
+                cat.setRequiresMcRestart(true);
+            }
+            if (field.isAnnotationPresent(Config.RequiresWorldRestart.class)) {
+                cat.setRequiresWorldRestart(true);
+            }
+        }
+    }
+}