From 67a9721bb5a4ca03d896a7cf4de6efee554d036c Mon Sep 17 00:00:00 2001
From: Brian Tripp <btripp365@gmail.com>
Date: Sat, 23 May 2026 15:56:17 -0500
Subject: [PATCH] refactor: decouple engine from world/processor creation

---
 .../hauntedhouse/engine/CliRunner.java        |  8 ++++++-
 .../hauntedhouse/engine/GameEngine.java       | 21 ++++++++++++++-----
 .../hauntedhouse/service/GameService.java     | 10 ++++++++-
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/src/main/java/com/bdtripp/hauntedhouse/engine/CliRunner.java b/src/main/java/com/bdtripp/hauntedhouse/engine/CliRunner.java
index ba55eb3..823bf87 100644
--- a/src/main/java/com/bdtripp/hauntedhouse/engine/CliRunner.java
+++ b/src/main/java/com/bdtripp/hauntedhouse/engine/CliRunner.java
@@ -1,6 +1,7 @@
 package com.bdtripp.hauntedhouse.engine;
 
 import com.bdtripp.hauntedhouse.model.Command;
+import com.bdtripp.hauntedhouse.model.World;
 
 /**
  * Runs the game in a command-line environment.
@@ -12,12 +13,17 @@
  */
 public class CliRunner {
     private Parser parser = new Parser(System.in);
-    private GameEngine gameEngine = new GameEngine();
+    private GameEngine gameEngine;
 
     /**
      * Initializes the parser and game engine for cli play.
      */
     public CliRunner() {
+        World world = new WorldBuilder().createWorld();
+        GameEngine engine = new GameEngine(world);
+        CommandProcessor processor = new CommandProcessor(world, engine);
+        engine.setCommandProcessor(processor);
+        this.gameEngine = engine;
     }
 
     /**
diff --git a/src/main/java/com/bdtripp/hauntedhouse/engine/GameEngine.java b/src/main/java/com/bdtripp/hauntedhouse/engine/GameEngine.java
index 161cfac..713a70c 100644
--- a/src/main/java/com/bdtripp/hauntedhouse/engine/GameEngine.java
+++ b/src/main/java/com/bdtripp/hauntedhouse/engine/GameEngine.java
@@ -19,15 +19,26 @@
  */
 public class GameEngine {
     private final World world;
-    private final CommandProcessor commandProcessor;
+    private CommandProcessor commandProcessor;
     private boolean gameOver;
 
     /**
-     * Creates the GameEngine and the game world.
+     * Creates the GameEngine.
      */
-    public GameEngine() {
-        world = new WorldBuilder().createWorld();
-        commandProcessor = new CommandProcessor(world, this);
+    public GameEngine(World world) {
+        this.world = world;
+    }
+
+    /**
+     * Injects the CommandProcessor used by the engine to interpret and execute player commands.
+     *
+     * This setter is required because the CommandProcessor also depends on the GameEngine, and
+     * therefore cannot be constructed until after the engine itself is created.
+     *
+     * @param processor the CommandProcessor responsible for handling commands
+     */
+    public void setCommandProcessor(CommandProcessor processor) {
+        this.commandProcessor = processor;
     }
 
     /**
diff --git a/src/main/java/com/bdtripp/hauntedhouse/service/GameService.java b/src/main/java/com/bdtripp/hauntedhouse/service/GameService.java
index c04486c..d796694 100644
--- a/src/main/java/com/bdtripp/hauntedhouse/service/GameService.java
+++ b/src/main/java/com/bdtripp/hauntedhouse/service/GameService.java
@@ -1,11 +1,15 @@
 package com.bdtripp.hauntedhouse.service;
 
 import com.bdtripp.hauntedhouse.engine.Parser;
+import com.bdtripp.hauntedhouse.engine.WorldBuilder;
 import com.bdtripp.hauntedhouse.model.Command;
 import com.bdtripp.hauntedhouse.api.GameRequest;
 import com.bdtripp.hauntedhouse.api.GameResponse;
+import com.bdtripp.hauntedhouse.engine.CommandProcessor;
 import com.bdtripp.hauntedhouse.engine.GameEngine;
 import com.bdtripp.hauntedhouse.model.GameStatus;
+import com.bdtripp.hauntedhouse.model.World;
+
 import org.springframework.stereotype.Service;
 import org.springframework.web.context.annotation.SessionScope;
 
@@ -32,7 +36,11 @@ public GameService() {
      * @return a response containing a welcome message and status of the game
      */
     public GameResponse startGame() {
-        gameEngine = new GameEngine();
+        World world = new WorldBuilder().createWorld();
+        GameEngine engine = new GameEngine(world);
+        CommandProcessor processor = new CommandProcessor(world, engine);
+        engine.setCommandProcessor(processor);
+        this.gameEngine = engine;
         gameEngine.startGame();
         String output = gameEngine.buildWelcomeMessage() + "\n";
         return new GameResponse(output, GameStatus.RUNNING);