add dependency injection API

common/src/main/java/com/dfsek/terra/addons/injection/Inject.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.injection;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.FIELD)
+public @interface Inject {
+}

common/src/main/java/com/dfsek/terra/addons/injection/InjectionException.java

@@ -0,0 +1,13 @@
+package com.dfsek.terra.addons.injection;
+
+public class InjectionException extends Exception {
+    private static final long serialVersionUID = -6929631447064215387L;
+
+    public InjectionException(String message) {
+        super(message);
+    }
+
+    public InjectionException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

common/src/main/java/com/dfsek/terra/addons/injection/Injector.java

@@ -0,0 +1,47 @@
+package com.dfsek.terra.addons.injection;
+
+import com.dfsek.terra.api.util.ReflectionUtil;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.util.HashSet;
+import java.util.Set;
+
+public class Injector<T> {
+    private final T value;
+    private final Set<Class<? extends T>> targets = new HashSet<>();
+
+    public Injector(T value) {
+        this.value = value;
+    }
+
+    public void addExplicitTarget(Class<? extends T> target) {
+        targets.add(target);
+    }
+
+    public void inject(Object object) throws InjectionException {
+        for(Field field : ReflectionUtil.getFields(object.getClass())) {
+            Inject inject = field.getAnnotation(Inject.class);
+            if(inject == null) continue;
+
+            System.out.println(field);
+            System.out.println("attempting to inject " + value.getClass() + " to " + field.getClass());
+            if(value.getClass().equals(field.getType()) || targets.contains(field.getType())) {
+                System.out.println("injecting...");
+                int mod = field.getModifiers();
+                if(Modifier.isFinal(mod)) {
+                    throw new InjectionException("Attempted to inject final field: " + field);
+                }
+                if(Modifier.isStatic(mod)) {
+                    throw new InjectionException("Attempted to inject static field: " + field);
+                }
+                field.setAccessible(true);
+                try {
+                    field.set(object, value);
+                } catch(IllegalAccessException e) {
+                    throw new InjectionException("Failed to inject field: " + field, e);
+                }
+            }
+        }
+    }
+}

common/src/main/java/com/dfsek/terra/addons/loading/pre/PreLoadAddon.java

@@ -4,6 +4,8 @@ import com.dfsek.terra.addons.addon.TerraAddon;
 import com.dfsek.terra.addons.annotations.Addon;
 import com.dfsek.terra.addons.annotations.Depends;
 import com.dfsek.terra.addons.loading.AddonLoadException;
+import com.dfsek.terra.addons.loading.pre.exception.CircularDependencyException;
+import com.dfsek.terra.addons.loading.pre.exception.DependencyMissingException;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -32,7 +34,8 @@ public class PreLoadAddon {
 
         for(String dependency : dependencies) {
             PreLoadAddon preLoadAddon = pool.get(dependency);
-            if(preLoadAddon == null) throw new DependencyMissingException("Dependency " + dependency + " was not found.");
+            if(preLoadAddon == null)
+                throw new DependencyMissingException("Dependency " + dependency + " was not found. Please install " + dependency + " to use " + id + ".");
             depends.add(preLoadAddon);
             preLoadAddon.rebuildDependencies(pool, origin, false);
         }

common/src/main/java/com/dfsek/terra/addons/loading/pre/exception/CircularDependencyException.java

@@ -1,4 +1,4 @@
-package com.dfsek.terra.addons.loading.pre;
+package com.dfsek.terra.addons.loading.pre.exception;
 
 import com.dfsek.terra.addons.loading.AddonLoadException;
 

common/src/main/java/com/dfsek/terra/addons/loading/pre/exception/DependencyMissingException.java

@@ -1,4 +1,4 @@
-package com.dfsek.terra.addons.loading.pre;
+package com.dfsek.terra.addons.loading.pre.exception;
 
 import com.dfsek.terra.addons.loading.AddonLoadException;
 

common/src/main/java/com/dfsek/terra/api/core/event/TerraEventManager.java

@@ -34,7 +34,11 @@ public class TerraEventManager implements EventManager {
                     try {
                         if(event instanceof PackEvent && !listenerHolder.global) {
                             PackEvent packEvent = (PackEvent) event;
-                            if(packEvent.getPack().getTemplate().getAddons().contains(listenerHolder.addon)) {
+                            if(packEvent
+                                    .getPack()
+                                    .getTemplate()
+                                    .getAddons()
+                                    .contains(listenerHolder.addon)) {
                                 listenerHolder.method.invoke(listenerHolder.listener, event);
                             }
                         } else {

common/src/main/java/com/dfsek/terra/config/pack/ConfigPackTemplate.java

@@ -8,6 +8,7 @@ import com.dfsek.terra.api.util.seeded.NoiseSeeded;
 import com.dfsek.terra.config.loaders.config.function.FunctionTemplate;
 
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
@@ -22,7 +23,7 @@ public class ConfigPackTemplate implements ConfigTemplate {
 
     @Value("addons")
     @Default
-    private Set<TerraAddon> addons;
+    private Set<TerraAddon> addons = new HashSet<>();
 
     @Value("variables")
     @Default

common/src/main/java/com/dfsek/terra/registry/AddonRegistry.java

@@ -1,6 +1,8 @@
 package com.dfsek.terra.registry;
 
 import com.dfsek.terra.addons.addon.TerraAddon;
+import com.dfsek.terra.addons.injection.InjectionException;
+import com.dfsek.terra.addons.injection.Injector;
 import com.dfsek.terra.addons.loading.AddonClassLoader;
 import com.dfsek.terra.addons.loading.AddonLoadException;
 import com.dfsek.terra.addons.loading.pre.AddonPool;
@@ -11,6 +13,8 @@ import java.io.File;
 import java.io.IOException;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
+import java.util.logging.LogManager;
+import java.util.logging.Logger;
 
 public class AddonRegistry extends TerraRegistry<TerraAddon> {
     private final TerraPlugin main;
@@ -39,6 +43,9 @@ public class AddonRegistry extends TerraRegistry<TerraAddon> {
     }
 
     public boolean loadAll() {
+        Injector<TerraPlugin> pluginInjector = new Injector<>(main);
+        pluginInjector.addExplicitTarget(TerraPlugin.class);
+
         boolean valid = true;
         File addonsFolder = new File(main.getDataFolder(), "addons");
         addonsFolder.mkdirs();
@@ -59,6 +66,16 @@ public class AddonRegistry extends TerraRegistry<TerraAddon> {
                 Class<? extends TerraAddon> addonClass = addon.getAddonClass();
                 Constructor<? extends TerraAddon> constructor;
 
+                String logPrefix = "Terra:" + addon.getId();
+                Logger addonLogger = Logger.getLogger(logPrefix);
+
+                if(!LogManager.getLogManager().addLogger(addonLogger)) {
+                    addonLogger = LogManager.getLogManager().getLogger(logPrefix);
+                }
+
+                Injector<Logger> loggerInjector = new Injector<>(addonLogger);
+                loggerInjector.addExplicitTarget(Logger.class);
+
                 try {
                     constructor = addonClass.getConstructor();
                 } catch(NoSuchMethodException e) {
@@ -67,7 +84,9 @@ public class AddonRegistry extends TerraRegistry<TerraAddon> {
                 TerraAddon loadedAddon;
                 try {
                     loadedAddon = constructor.newInstance();
-                } catch(InstantiationException | IllegalAccessException | InvocationTargetException e) {
+                    pluginInjector.inject(loadedAddon);
+                    loggerInjector.inject(loadedAddon);
+                } catch(InstantiationException | IllegalAccessException | InvocationTargetException | InjectionException e) {
                     throw new AddonLoadException("Failed to load addon \" + " + addon.getId() + "\": ", e);
                 }
                 try {