Reorganise kotlin message handlers

game/src/main/kotlin/org/apollo/game/plugin/kotlin/KotlinCommandHandler.kt

@@ -13,17 +13,29 @@ class KotlinCommandHandler(
     val world: World,
     val command: String,
     privileges: PrivilegeLevel
-) : KotlinPlayerHandlerProxyTrait<Command>, CommandListener(privileges) {
+) : CommandListener(privileges) {
 
-    override var callback: Command.(Player) -> Unit = {}
-    override var predicate: Command.() -> Boolean = { true }
+    var callback: Command.(Player) -> Unit = {}
+    var predicate: Command.() -> Boolean = { true }
 
     override fun execute(player: Player, command: Command) {
-        handleProxy(player, command)
+        if (command.predicate()) {
+            command.callback(player)
+        }
     }
 
-    override fun register() {
+    fun register() {
         world.commandDispatcher.register(command, this)
     }
 
+    fun where(predicate: Command.() -> Boolean): KotlinCommandHandler {
+        this.predicate = predicate
+        return this
+    }
+
+    fun then(callback: Command.(Player) -> Unit) {
+        this.callback = callback
+        this.register()
+    }
+
 }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/KotlinMessageHandler.kt

@@ -7,15 +7,15 @@ import org.apollo.game.plugin.PluginContext
 import org.apollo.net.message.Message
 import kotlin.reflect.KClass
 
-class KotlinMessageHandler<T : ListenableContext, F : Message>(
+class KotlinMessageHandler<F : Message, T : ListenableContext>(
     world: World,
-    private val listenable: MessageListenable<T, F>,
+    private val listenable: MessageListenable<F, T>,
     private val callback: T.() -> Unit
 ) : MessageHandler<F>(world) {
 
     override fun handle(player: Player, message: F) {
-        val context = listenable.from(player, message)
-        context.callback()
+        val context = listenable.createContext(player, message)
+        context?.callback()
     }
 
 }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/KotlinPluginScript.kt

@@ -20,34 +20,34 @@ abstract class KotlinPluginScript(var world: World, val context: PluginContext)
 
     private var stopListener: (World) -> Unit = { _ -> }
 
-    fun <T : ListenableContext, F : Any> on(listenable: Listenable<T, F>, callback: T.() -> Unit) {
+    fun <T : Any, C : ListenableContext> on(listenable: Listenable<T, C>, callback: C.() -> Unit) {
         // Smart-casting/type-inference is completely broken in this function in intelliJ, so assign to otherwise
         // pointless `l` values for now.
 
         return when (listenable) {
             is MessageListenable -> {
                 @Suppress("UNCHECKED_CAST")
-                val l = listenable as MessageListenable<T, Message>
+                val l = listenable as MessageListenable<Message, C>
 
                 val handler = KotlinMessageHandler(world, l, callback)
                 context.addMessageHandler(l.type.java, handler)
             }
             is PlayerEventListenable -> {
                 @Suppress("UNCHECKED_CAST")
-                val l = listenable as PlayerEventListenable<T, PlayerEvent>
+                val l = listenable as PlayerEventListenable<PlayerEvent, C>
 
                 world.listenFor(l.type.java) { event ->
-                    val context = l.from(event)
-                    context.callback()
+                    val context = l.createContext(event)
+                    context?.callback()
                 }
             }
             is EventListenable -> {
                 @Suppress("UNCHECKED_CAST")
-                val l = listenable as EventListenable<T, Event>
+                val l = listenable as EventListenable<Event, C>
 
                 world.listenFor(l.type.java) { event ->
-                    val context = l.from(event)
-                    context.callback()
+                    val context = l.createContext(event)
+                    context?.callback()
                 }
             }
         }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/Listenable.kt

@@ -9,24 +9,24 @@ import kotlin.reflect.KClass
 /**
  * A game occurrence that can be listened to.
  */
-sealed class Listenable<T : ListenableContext, F : Any> {
-    abstract val type: KClass<F>
+sealed class Listenable<T : Any, C : ListenableContext> {
+    abstract val type: KClass<T>
 }
 
-abstract class EventListenable<T : ListenableContext, F : Event> : Listenable<T, F>() {
-    abstract fun from(event: F): T
+abstract class EventListenable<T : Event, C : ListenableContext> : Listenable<T, C>() {
+    abstract fun createContext(event: T): C?
 }
 
-abstract class MessageListenable<T : ListenableContext, F : Message> : Listenable<T, F>() {
-    abstract fun from(player: Player, message: F): T
+abstract class MessageListenable<T : Message, C : ListenableContext> : Listenable<T, C>() {
+    abstract fun createContext(player: Player, message: T): C?
 }
 
-abstract class PlayerEventListenable<T : ListenableContext, F : PlayerEvent> : EventListenable<T, F>() {
+abstract class PlayerEventListenable<T : PlayerEvent, C : ListenableContext> : EventListenable<T, C>() {
 
-    abstract fun from(player: Player, event: F): T
+    abstract fun createContext(player: Player, event: T): C?
 
-    override fun from(event: F): T {
-        return from(event.player, event)
+    final override fun createContext(event: T): C? {
+        return createContext(event.player, event)
     }
 
 }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/ListenableContext.kt

@@ -1,6 +1,15 @@
 package org.apollo.game.plugin.kotlin
 
+import org.apollo.game.model.entity.Player
+
 /**
- * Contains contextual information for a [Listenable].
+ * Contextual information for a [Listenable].
  */
 interface ListenableContext
+
+/**
+ * Contextual information for a [Listenable] involving a specific [Player].
+ */
+interface PlayerContext : ListenableContext {
+    val player: Player
+}

game/src/main/kotlin/org/apollo/game/plugin/kotlin/action/obj/ObjectAction.kt

@@ -1,53 +0,0 @@
-package org.apollo.game.plugin.kotlin.action.obj
-
-import org.apollo.cache.def.ObjectDefinition
-import org.apollo.game.message.impl.ObjectActionMessage
-import org.apollo.game.model.entity.EntityType
-import org.apollo.game.model.entity.Player
-import org.apollo.game.model.entity.obj.GameObject
-import org.apollo.game.plugin.kotlin.action.ActionListenableContext
-
-/**
- * An interaction between a [Player] and an [interactive] [GameObject].
- */
-class ObjectAction<T : InteractiveObject?>(
-    override val option: String,
-    override val player: Player,
-    val target: GameObject,
-    val interactive: T
-) : ActionListenableContext {
-
-    companion object : ObjectActionListenable() {
-
-        override fun from(player: Player, message: ObjectActionMessage): ObjectAction<*> {
-            val def = ObjectDefinition.lookup(message.id)
-            val selectedAction = def.menuActions[message.option]
-
-            val obj = player.world.regionRepository
-                .fromPosition(message.position)
-                .getEntities<GameObject>(message.position, EntityType.DYNAMIC_OBJECT, EntityType.STATIC_OBJECT)
-                .first { it.definition == def }
-
-            return ObjectAction(selectedAction, player, obj, null)
-        }
-
-        override val type = ObjectActionMessage::class
-
-        override fun <T : InteractiveObject> from(
-            player: Player,
-            other: ObjectActionMessage,
-            objects: List<T>
-        ): ObjectAction<T> {
-            val def = ObjectDefinition.lookup(other.id)
-            val selectedAction = def.menuActions[other.option]
-
-            val obj = player.world.regionRepository
-                .fromPosition(other.position)
-                .getEntities<GameObject>(other.position, EntityType.DYNAMIC_OBJECT, EntityType.STATIC_OBJECT)
-                .first { it.definition == def }
-
-            return ObjectAction(selectedAction, player, obj, objects.first { it.instanceOf(obj) })
-        }
-    }
-
-}

game/src/main/kotlin/org/apollo/game/plugin/kotlin/message/action/ActionContext.kt

@@ -1,9 +1,8 @@
-package org.apollo.game.plugin.kotlin.action
+package org.apollo.game.plugin.kotlin.message.action
 
-import org.apollo.game.model.entity.Player
 import org.apollo.game.plugin.kotlin.KotlinPluginScript
-import org.apollo.game.plugin.kotlin.ListenableContext
 import org.apollo.game.plugin.kotlin.MessageListenable
+import org.apollo.game.plugin.kotlin.PlayerContext
 import org.apollo.net.message.Message
 
 /**
@@ -15,8 +14,8 @@ import org.apollo.net.message.Message
  * }
  * ```
  */
-inline fun <T : ActionListenableContext, reified F : Message> KotlinPluginScript.on(
-    listenable: MessageListenable<T, F>,
+inline fun <T : ActionContext, reified F : Message> KotlinPluginScript.on(
+    listenable: MessageListenable<F, T>,
     option: String,
     crossinline callback: T.() -> Unit
 ) {
@@ -27,7 +26,6 @@ inline fun <T : ActionListenableContext, reified F : Message> KotlinPluginScript
     }
 }
 
-interface ActionListenableContext : ListenableContext {
+interface ActionContext : PlayerContext {
     val option: String
-    val player: Player
 }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/message/action/obj/InteractiveObject.kt

@@ -1,4 +1,4 @@
-package org.apollo.game.plugin.kotlin.action.obj
+package org.apollo.game.plugin.kotlin.message.action.obj
 
 import org.apollo.game.model.entity.obj.GameObject
 

game/src/main/kotlin/org/apollo/game/plugin/kotlin/message/action/obj/ObjectAction.kt

@@ -0,0 +1,60 @@
+package org.apollo.game.plugin.kotlin.message.action.obj
+
+import org.apollo.cache.def.ObjectDefinition
+import org.apollo.game.message.impl.ObjectActionMessage
+import org.apollo.game.model.entity.EntityType
+import org.apollo.game.model.entity.Player
+import org.apollo.game.model.entity.obj.GameObject
+import org.apollo.game.plugin.kotlin.message.action.ActionContext
+
+/**
+ * An interaction between a [Player] and an [interactive] [GameObject].
+ */
+class ObjectAction<T : InteractiveObject?>( // TODO split into two classes, one with T and one without?
+    override val player: Player,
+    override val option: String,
+    val target: GameObject,
+    val interactive: T
+) : ActionContext {
+
+    companion object : ObjectActionListenable() {
+
+        override val type = ObjectActionMessage::class
+
+        override fun createContext(player: Player, message: ObjectActionMessage): ObjectAction<*>? {
+            return create<InteractiveObject>(player, message, objects = null)
+        }
+
+        override fun <T : InteractiveObject> createContext(
+            player: Player,
+            other: ObjectActionMessage,
+            objects: List<T>
+        ): ObjectAction<T>? {
+            @Suppress("UNCHECKED_CAST")
+            return create(player, other, objects) as ObjectAction<T>
+        }
+
+        private fun <T : InteractiveObject> create(
+            player: Player,
+            other: ObjectActionMessage,
+            objects: List<T>?
+        ): ObjectAction<*>? {
+            val def = ObjectDefinition.lookup(other.id)
+            val selectedAction = def.menuActions[other.option]
+
+            val obj = player.world.regionRepository
+                .fromPosition(other.position)
+                .getEntities<GameObject>(other.position, EntityType.DYNAMIC_OBJECT, EntityType.STATIC_OBJECT)
+                .find { it.definition == def }
+                ?: return null
+
+            if (objects == null) {
+                return ObjectAction(player, selectedAction, obj, null)
+            } else {
+                val interactive = objects.find { it.instanceOf(obj) } ?: return null
+                return ObjectAction(player, selectedAction, obj, interactive)
+            }
+        }
+    }
+
+}

game/src/main/kotlin/org/apollo/game/plugin/kotlin/message/action/obj/ObjectActionListenable.kt

@@ -1,17 +1,17 @@
-package org.apollo.game.plugin.kotlin.action.obj
+package org.apollo.game.plugin.kotlin.message.action.obj
 
 import org.apollo.game.message.impl.ObjectActionMessage
 import org.apollo.game.model.entity.Player
 import org.apollo.game.plugin.kotlin.MessageListenable
 
-abstract class ObjectActionListenable : MessageListenable<ObjectAction<*>, ObjectActionMessage>() {
+abstract class ObjectActionListenable : MessageListenable<ObjectActionMessage, ObjectAction<*>>() {
 
     override val type = ObjectActionMessage::class
 
-    abstract fun <T : InteractiveObject> from(
+    abstract fun <T : InteractiveObject> createContext(
         player: Player,
         other: ObjectActionMessage,
         objects: List<T>
-    ): ObjectAction<T>
+    ): ObjectAction<T>?
 
 }

game/src/main/kotlin/org/apollo/game/plugin/kotlin/message/action/obj/ObjectActionMessageHandler.kt

@@ -1,4 +1,4 @@
-package org.apollo.game.plugin.kotlin.action.obj
+package org.apollo.game.plugin.kotlin.message.action.obj
 
 import org.apollo.cache.def.ObjectDefinition
 import org.apollo.game.message.handler.MessageHandler
@@ -8,18 +8,6 @@ import org.apollo.game.model.entity.EntityType
 import org.apollo.game.model.entity.Player
 import org.apollo.game.model.entity.obj.GameObject
 import org.apollo.game.plugin.kotlin.KotlinPluginScript
-import org.apollo.game.plugin.kotlin.action.on
-
-@Deprecated("example function, remove")
-fun KotlinPluginScript.x() {
-    on(ObjectAction, option = "Trade", objects = listOf()) {
-
-    }
-
-    on(ObjectAction, option = "Trade") {
-
-    }
-}
 
 /**
  * Registers a listener for [ObjectActionMessage]s that occur on any of the given [InteractiveObject]s using the
@@ -27,7 +15,7 @@ fun KotlinPluginScript.x() {
  *
  * ```
  * on(ObjectAction, option = "Open", objects = DOORS.toList()) {
- *     player.sendMessage("You open the door")
+ *     player.sendMessage("You open the door.")
  * }
  * ```
  */
@@ -39,10 +27,8 @@ fun <T : InteractiveObject> KotlinPluginScript.on(
 ) {
     if (objects.isEmpty()) {
         on(listenable) {
-            if (this.option.equals(option, ignoreCase = true)) {
-                @Suppress("UNCHECKED_CAST") (this as ObjectAction<T>)
-                callback()
-            }
+            @Suppress("UNCHECKED_CAST") (callback as ObjectAction<*>.() -> Unit)
+            callback(this)
         }
     } else {
         val handler = ObjectActionMessageHandler(world, listenable, objects, option, callback)
@@ -50,9 +36,6 @@ fun <T : InteractiveObject> KotlinPluginScript.on(
     }
 }
 
-/**
- * A [MessageHandler]
- */
 class ObjectActionMessageHandler<T : InteractiveObject>(
     world: World,
     private val listenable: ObjectActionListenable,
@@ -71,8 +54,8 @@ class ObjectActionMessageHandler<T : InteractiveObject>(
             .first { it.definition == def }
 
         if (option.equals(selectedAction, ignoreCase = true) && objects.any { it.instanceOf(obj) }) {
-            val context = listenable.from(player, message, objects)
-            context.callback()
+            val context = listenable.createContext(player, message, objects)
+            context?.callback()
         }
     }