feat: crude drop tables with sample

game/plugins/src/main/kotlin/gg/rsmod/plugins/content/npcs/man/man_chat.plugin.kts

@@ -9,6 +9,15 @@ MEN.forEach { man ->
     on_npc_option(npc = man, option = "talk-to") {
         player.queue { chat(this) }
     }
+
+    npc_drop_table(npc = man) {
+        val map = HashMap<Int, Int>()
+        map[Items.BONES] = 1
+        if(world.random(1..10) == 4) {
+            map[Items.COINS_995] = 100
+        }
+        map
+    }
 }
 
 suspend fun chat(it: QueueTask) {

game/src/main/kotlin/gg/rsmod/game/action/NpcDeathAction.kt

@@ -3,6 +3,7 @@ package gg.rsmod.game.action
 import gg.rsmod.game.fs.def.AnimDef
 import gg.rsmod.game.model.LockState
 import gg.rsmod.game.model.attr.KILLER_ATTR
+import gg.rsmod.game.model.entity.GroundItem
 import gg.rsmod.game.model.entity.Npc
 import gg.rsmod.game.model.entity.Player
 import gg.rsmod.game.model.queue.QueueTask
@@ -34,12 +35,16 @@ object NpcDeathAction {
         val world = npc.world
         val deathAnimation = npc.combatDef.deathAnimation
         val respawnDelay = npc.combatDef.respawnDelay
+        val killer = npc.damageMap.getMostDamage()
 
-        npc.damageMap.getMostDamage()?.let { killer ->
-            if (killer is Player) {
-                world.getService(LoggerService::class.java, searchSubclasses = true)?.logNpcKill(killer, npc)
+        npc.stopMovement()
+        npc.lock()
+
+        npc.damageMap.getMostDamage()?.let { _killer ->
+            if (_killer is Player) {
+                world.getService(LoggerService::class.java, searchSubclasses = true)?.logNpcKill(_killer, npc)
             }
-            npc.attr[KILLER_ATTR] = WeakReference(killer)
+            npc.attr[KILLER_ATTR] = WeakReference(_killer)
         }
 
         world.plugins.executeNpcPreDeath(npc)
@@ -56,6 +61,12 @@ object NpcDeathAction {
 
         world.plugins.executeNpcDeath(npc)
 
+        val drops = world.plugins.executeNpcDropTable(killer, npc.id)
+
+        drops?.forEach { id, amount ->
+            world.spawn(GroundItem(id, amount, npc.tile, killer as? Player))
+        }
+
         if (npc.respawns) {
             npc.invisible = true
             npc.reset()

game/src/main/kotlin/gg/rsmod/game/plugin/KotlinPlugin.kt

@@ -516,6 +516,8 @@ abstract class KotlinPlugin(private val r: PluginRepository, val world: World, v
      */
     fun on_item_on_npc(item: Int, npc: Int, plugin: Plugin.() -> Unit) = r.bindItemOnNpc(npc = npc, item = item, plugin = plugin)
 
+    fun npc_drop_table(npc: Int, plugin: (Plugin).() -> HashMap<Int, Int>?) = r.bindNpcDropTable(npc = npc, plugin = plugin)
+
     companion object {
         private val METADATA_PATH = Paths.get("./plugins", "configs")
     }

game/src/main/kotlin/gg/rsmod/game/plugin/PluginRepository.kt

@@ -331,6 +331,12 @@ class PluginRepository(val world: World) {
      */
     private val npcDeathPlugins = Int2ObjectOpenHashMap<Plugin.() -> Unit>()
 
+    /**
+     * A list of plugin that will be invoked when an npc dies
+     * and invokes its drop table
+     */
+    private val npcDropsPlugins = Int2ObjectOpenHashMap<Plugin.() -> HashMap<Int, Int>?>()
+
     /**
      * A map of plugins that occur when an [Event] is triggered.
      */
@@ -1253,5 +1259,20 @@ class PluginRepository(val world: World) {
         }
     }
 
+    fun bindNpcDropTable(npc: Int, plugin: Plugin.() -> HashMap<Int, Int>?) {
+        if (npcDropsPlugins.containsKey(npc)) {
+            val error = java.lang.IllegalStateException("Npc drop table is already bound to a plugin: npc=$npc")
+            logger.error(error) {}
+            throw error
+        }
+        npcDropsPlugins[npc] = plugin
+        pluginCount++
+    }
+
+    fun executeNpcDropTable(p: Pawn?, npc: Int): HashMap<Int, Int>? {
+        val plugin = npcDropsPlugins[npc] ?: return null
+        return p?.executePlugin(plugin)
+    }
+
     companion object : KLogging()
 }