From 90e33de7f262e0fa9ba4db1b32e1b3674b59a1f8 Mon Sep 17 00:00:00 2001
From: "Z. Cliffe Schreuders" <code.cliffe@schreuders.org>
Date: Sun, 9 Nov 2025 23:56:42 +0000
Subject: [PATCH] feat(npc): Implement NPC-to-NPC collision detection in rooms

---
 js/core/rooms.js          |  3 +++
 js/systems/npc-sprites.js | 41 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/js/core/rooms.js b/js/core/rooms.js
index 0ae01a3..e3fbfc1 100644
--- a/js/core/rooms.js
+++ b/js/core/rooms.js
@@ -1912,6 +1912,9 @@ function createNPCSpritesForRoom(roomId, roomData) {
                     // Set up wall and chair collisions (same as player gets)
                     NPCSpriteManager.setupNPCEnvironmentCollisions(gameRef, sprite, roomId);
 
+                    // Set up NPC-to-NPC collisions with all other NPCs in this room
+                    NPCSpriteManager.setupNPCToNPCCollisions(gameRef, sprite, roomId, roomData.npcSprites);
+
                     // Register behavior if configured
                     // Only for sprite-based NPCs (not phone-only)
                     if (window.npcBehaviorManager && npc.behavior) {
diff --git a/js/systems/npc-sprites.js b/js/systems/npc-sprites.js
index 4c6b157..2a2ad3c 100644
--- a/js/systems/npc-sprites.js
+++ b/js/systems/npc-sprites.js
@@ -48,7 +48,6 @@ export function createNPCSprite(scene, npc, roomData) {
         
         // Enable physics
         scene.physics.add.existing(sprite);
-        sprite.body.immovable = true; // NPCs don't move on collision
         // Set smaller collision box at the feet (matching player collision: 18x10 with similar offset)
         sprite.body.setSize(18, 10); // Collision body size (wider for better hit detection)
         sprite.body.setOffset(23, 50); // Offset for feet position (64px sprite, adjusted for wider box)
@@ -498,6 +497,45 @@ export function setupNPCEnvironmentCollisions(scene, npcSprite, roomId) {
     setupNPCChairCollisions(scene, npcSprite, roomId);
 }
 
+/**
+ * Set up collisions between an NPC sprite and all other NPCs in the room
+ * 
+ * Called after creating each NPC sprite to enable NPC-to-NPC collision detection.
+ * 
+ * @param {Phaser.Scene} scene - Phaser scene instance
+ * @param {Phaser.Sprite} npcSprite - NPC sprite to collide with others
+ * @param {string} roomId - Room ID where NPC is located
+ * @param {Array} allNPCSprites - Array of all NPC sprites in the room
+ */
+export function setupNPCToNPCCollisions(scene, npcSprite, roomId, allNPCSprites) {
+    if (!npcSprite || !npcSprite.body) {
+        return;
+    }
+    
+    if (!allNPCSprites || !Array.isArray(allNPCSprites)) {
+        return;
+    }
+    
+    const game = scene || window.game;
+    if (!game) {
+        console.warn('❌ Cannot set up NPC-to-NPC collisions: no game reference');
+        return;
+    }
+    
+    // Add collision with all other NPCs
+    let collisionsAdded = 0;
+    allNPCSprites.forEach(otherNPC => {
+        if (otherNPC && otherNPC !== npcSprite && otherNPC.body) {
+            game.physics.add.collider(npcSprite, otherNPC);
+            collisionsAdded++;
+        }
+    });
+    
+    if (collisionsAdded > 0) {
+        console.log(`👥 NPC ${npcSprite.npcId}: ${collisionsAdded} NPC-to-NPC collision(s) set up`);
+    }
+}
+
 // Export for module namespace
 export default {
     createNPCSprite,
@@ -508,6 +546,7 @@ export default {
     setupNPCWallCollisions,
     setupNPCChairCollisions,
     setupNPCEnvironmentCollisions,
+    setupNPCToNPCCollisions,
     playNPCAnimation,
     returnNPCToIdle,
     destroyNPCSprite,