EaglerForgeInjector/examplemods/npcspawner.js

(() => {
    PluginAPI.dedicatedServer.appendCode(function () {
        var ready = false;
        var killFS = false;
        function setup_filesystem_middleware() {
            if (!ready) {
                AsyncSink.MIDDLEWARE.push((ev)=>{
                    if (killFS) {
                        ev.shim = true;
                        if (typeof ev.shimOutput === "boolean") {
                            ev.shimOutput = true;
                        }
                    }
                });
                ready = true;
            }
        }
        PluginAPI.addEventListener("processcommand", (event) => {
            if (!ModAPI.reflect.getClassById("net.minecraft.entity.player.EntityPlayerMP").instanceOf(event.sender.getRef())) { return; }

            if (event.command.toLowerCase().startsWith("/spawnnpc")) {
                if (!globalThis.AsyncSink) {
                    return console.error("NPC Spawner relies on the AsyncSink library.");
                }
                setup_filesystem_middleware();
                const world = event.sender.getServerForPlayer();
                const senderPos = event.sender.getPosition();

                // Create a fake player GameProfile
                const GameProfileClass = ModAPI.reflect.getClassById("net.lax1dude.eaglercraft.v1_8.mojang.authlib.GameProfile");
                var UUID = ModAPI.hooks.methods[ModAPI.util.getMethodFromPackage("net.lax1dude.eaglercraft.v1_8.EaglercraftUUID", "randomUUID")]();

                //Not using UUID to make patching easier for now
                
                const fakeProfile = GameProfileClass.constructors[1](null, ModAPI.util.str("Steve"));

                // Get the PlayerInteractionManager class
                const PlayerInteractionManagerClass = ModAPI.reflect.getClassById("net.minecraft.server.management.ItemInWorldManager");
                const playerInteractionManager = PlayerInteractionManagerClass.constructors[0](world.getRef());

                // Get the EntityPlayerMP class to spawn the fake player
                killFS = true;
                const EntityPlayerMPClass = ModAPI.reflect.getClassById("net.minecraft.entity.player.EntityPlayerMP");
                const fakePlayer = ModAPI.util.wrap(EntityPlayerMPClass.constructors[0](
                    ModAPI.server.getRef(), world.getRef(), fakeProfile, playerInteractionManager
                ));
                killFS = false;

                // Set the fake player position to be near the command sender
                console.log(senderPos);
                fakePlayer.setPosition(senderPos.getX(), senderPos.getY(), senderPos.getZ());

                // Add the fake player to the world
                world.spawnEntityInWorld(fakePlayer.getRef());

                // Notify the player that the fake player has been spawned
                const ChatComponentTextClass = ModAPI.reflect.getClassById("net.minecraft.util.ChatComponentText");
                event.sender.addChatMessage(ChatComponentTextClass.constructors[0](ModAPI.util.str("Fake Steve has been spawned!")));

                // Prevent the command from executing further
                event.preventDefault = true;
            }
        });
    });
})();