feat(manavoxel): clean up dead code, add portal keys, fix triggers, implement gold economy

Remove unused multiplayer protocol types, script/wasmBinary/capabilities fields,
and onNearItem trigger. Implement portal requiresKey gate, fix onDayNight and
onTouch triggers to fire for all inventory items, and add gold-based trading
economy with NPC kill rewards and merchant purchasing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/manavoxel/CLAUDE.md

@@ -125,7 +125,7 @@ GameEventBus          →  BehaviorRuntime         →  Action Executors
                                                       └── setVariable/sendEvent
 ```
 
-### Triggers (10 types)
+### Triggers (9 types)
 
 | Trigger | Fires when |
 |---------|-----------|
@@ -137,8 +137,7 @@ GameEventBus          →  BehaviorRuntime         →  Action Executors
 | `onHpBelow` | Player HP drops below threshold (with param check) |
 | `onAreaEnter` | Player enters a portal |
 | `onCustomEvent` | Fired by sendEvent action |
-| `onNearItem` | Item proximity (not yet wired) |
-| `onDayNight` | Day/night change (not yet implemented) |
+| `onDayNight` | Day/night change |
 
 ### Actions (11 implemented)
 
@@ -266,8 +265,9 @@ NPCs are spawned from EntityDef entries in area data. Place them via the NPC too
 - **Base64 encoding** — binary data (pixelData, spriteData) encoded for Dexie storage
 - **Svelte 5 runes** — `$state`, `$derived`, `$effect` for reactive UI state
 
-## Not Yet Implemented
+## Economy System
 
-- **Multiplayer** — 10+ message types defined, no WebSocket server
-- **Some triggers** — onNearItem not wired to game events yet
-- **Trading UI** — Merchant dialog opens but trade screen not yet implemented
+- **Gold** — Earned from defeating NPCs (hostile: 5-15g, guard: 10-25g)
+- **Merchants** — Buy items with gold, prices shown on buy button
+- **Persistence** — Gold saved/loaded with inventory in IndexedDB
+- **HUD** — Gold counter shown in top bar during gameplay

apps/manavoxel/apps/web/src/lib/data/world-loader.ts

@@ -149,7 +149,8 @@ export async function deleteItem(itemId: string): Promise<void> {
 export async function saveInventory(
 	playerId: string,
 	slots: (GameItem | null)[],
-	heldSlot: number
+	heldSlot: number,
+	gold: number = 0
 ): Promise<void> {
 	// Clear existing inventory for this player
 	const existing = await inventoryCollection.getAll({ playerId });
@@ -167,7 +168,19 @@ export async function saveInventory(
 			itemId: item.id,
 			slot: i,
 			quantity: 1,
-			instanceData: JSON.stringify({ heldSlot }),
+			instanceData: JSON.stringify({ heldSlot, gold }),
+		});
+	}
+
+	// Save gold even if inventory is empty
+	if (slots.every((s) => s === null)) {
+		await inventoryCollection.insert({
+			id: `${playerId}_meta`,
+			playerId,
+			itemId: '',
+			slot: -1,
+			quantity: 0,
+			instanceData: JSON.stringify({ heldSlot, gold }),
 		});
 	}
 }
@@ -175,20 +188,22 @@ export async function saveInventory(
 /** Load inventory from IndexedDB */
 export async function loadInventory(
 	playerId: string
-): Promise<{ slots: (string | null)[]; heldSlot: number }> {
+): Promise<{ slots: (string | null)[]; heldSlot: number; gold: number }> {
 	const dbSlots = await inventoryCollection.getAll({ playerId });
 	const slots: (string | null)[] = Array(8).fill(null);
 	let heldSlot = -1;
+	let gold = 0;
 
 	for (const dbSlot of dbSlots) {
 		if (dbSlot.slot >= 0 && dbSlot.slot < slots.length) {
 			slots[dbSlot.slot] = dbSlot.itemId;
 		}
-		const data = safeJsonParse<{ heldSlot?: number }>(dbSlot.instanceData, {});
+		const data = safeJsonParse<{ heldSlot?: number; gold?: number }>(dbSlot.instanceData, {});
 		if (data.heldSlot !== undefined) heldSlot = data.heldSlot;
+		if (data.gold !== undefined) gold = data.gold;
 	}
 
-	return { slots, heldSlot };
+	return { slots, heldSlot, gold };
 }
 
 function dbItemToGameItem(dbItem: LocalItem): GameItem {

apps/manavoxel/apps/web/src/lib/editor/trigger-editor.svelte

@@ -16,7 +16,6 @@
 		{ value: 'onDrop', label: 'Item dropped' },
 		{ value: 'onTimer', label: 'Every X seconds' },
 		{ value: 'onHpBelow', label: 'HP below X' },
-		{ value: 'onNearItem', label: 'Item nearby' },
 		{ value: 'onAreaEnter', label: 'Entering area' },
 		{ value: 'onCustomEvent', label: 'Custom event' },
 		{ value: 'onDayNight', label: 'Day/Night change' },

apps/manavoxel/apps/web/src/lib/engine/behavior.ts

@@ -18,7 +18,6 @@ export type GameEventType =
 	| 'onDrop'
 	| 'onTimer'
 	| 'onHpBelow'
-	| 'onNearItem'
 	| 'onAreaEnter'
 	| 'onCustomEvent'
 	| 'onDayNight';

apps/manavoxel/apps/web/src/lib/engine/dialog.ts

@@ -20,7 +20,7 @@ export interface DialogOption {
 
 export interface TradeOffer {
 	item: GameItem;
-	cost: number; // durability points from held item as "currency"
+	cost: number; // gold cost
 }
 
 // ─── NPC Dialog Templates ─────────────────────────────────────
@@ -148,7 +148,7 @@ export class DialogManager {
 export interface MerchantOffer {
 	name: string;
 	description: string;
-	cost: number; // durability points from held item
+	cost: number; // gold cost
 	damage: number;
 	range: number;
 	speed: number;
@@ -296,6 +296,19 @@ const GUARD_LOOT: LootDrop[] = [
 	},
 ];
 
+/** Gold reward ranges per NPC type */
+const GOLD_REWARDS: Record<string, { min: number; max: number }> = {
+	hostile: { min: 5, max: 15 },
+	guard: { min: 10, max: 25 },
+};
+
+/** Roll gold reward for a defeated NPC */
+export function rollGold(npcBehavior: string): number {
+	const reward = GOLD_REWARDS[npcBehavior];
+	if (!reward) return 0;
+	return reward.min + Math.floor(Math.random() * (reward.max - reward.min + 1));
+}
+
 /** Roll loot for a defeated NPC. Returns null if nothing drops. */
 export function rollLoot(npcBehavior: string): LootDrop | null {
 	const table = npcBehavior === 'guard' ? GUARD_LOOT : HOSTILE_LOOT;

apps/manavoxel/apps/web/src/lib/engine/game.ts

@@ -247,9 +247,9 @@ export class GameEngine {
 			const dnResult = this.dayNight.update();
 			this.lighting.setAmbient(this.dayNight.ambientLevel);
 
-			// Fire onDayNight trigger
-			if (dnResult.changed && this.inventory?.heldItem) {
-				this._fireItemEvent('onDayNight', this.inventory.heldItem);
+			// Fire onDayNight trigger for all inventory items
+			if (dnResult.changed) {
+				this._fireEventForAllItems('onDayNight');
 			}
 		}
 
@@ -290,10 +290,15 @@ export class GameEngine {
 				this._currentFloor
 			);
 			if (portal && this.input.isKeyDown('KeyE')) {
-				this.areaManager.enterPortal(portal, this.player);
-				// Fire onAreaEnter for held item
-				if (this.inventory?.heldItem) {
-					this._fireItemEvent('onAreaEnter', this.inventory.heldItem);
+				// Check if portal requires a key item
+				if (portal.requiresKey && !this.inventory?.hasItem(portal.requiresKey)) {
+					this.showMessage('You need a key to enter here.');
+				} else {
+					this.areaManager.enterPortal(portal, this.player);
+					// Fire onAreaEnter for held item
+					if (this.inventory?.heldItem) {
+						this._fireItemEvent('onAreaEnter', this.inventory.heldItem);
+					}
 				}
 			}
 
@@ -372,9 +377,9 @@ export class GameEngine {
 				this.onStateChange?.();
 			}
 
-			// Fire onTouch for held item when touching NPCs
-			if (npcResult.touchingNpcs.length > 0 && this.inventory?.heldItem) {
-				this._fireItemEvent('onTouch', this.inventory.heldItem);
+			// Fire onTouch for all inventory items when touching NPCs
+			if (npcResult.touchingNpcs.length > 0) {
+				this._fireEventForAllItems('onTouch');
 			}
 
 			// Item-use damages NPCs in range
@@ -405,7 +410,7 @@ export class GameEngine {
 						if (died) {
 							playSound('explosion');
 							this.particles.spawn('shatter', target.worldX, target.worldY);
-							this._showMessage(`Defeated ${target.behavior} NPC!`);
+							this.showMessage(`Defeated ${target.behavior} NPC!`);
 							this.onNpcDeath?.(target.worldX, target.worldY, target.behavior);
 						}
 					}
@@ -526,6 +531,14 @@ export class GameEngine {
 		this.eventBus.emit(event);
 	}
 
+	/** Fire an event for all items in inventory (for passive triggers like onDayNight, onTouch) */
+	private _fireEventForAllItems(type: import('./behavior').GameEventType) {
+		if (!this.inventory) return;
+		for (const item of this.inventory.slots) {
+			if (item) this._fireItemEvent(type, item);
+		}
+	}
+
 	/** Create an ActionContext for behavior execution */
 	private _createActionContext(item: import('./inventory.svelte').GameItem): ActionContext {
 		return {
@@ -559,7 +572,7 @@ export class GameEngine {
 				this.camera.shake(intensity, duration);
 			},
 			showMessage: (text: string) => {
-				this._showMessage(text);
+				this.showMessage(text);
 			},
 			item,
 		};
@@ -634,13 +647,13 @@ export class GameEngine {
 					const slotIdx = this.inventory.slots.findIndex((s) => s?.id === item.id);
 					if (slotIdx >= 0) this.inventory.removeItem(slotIdx);
 				}
-				this._showMessage(`${item.name} broke!`);
+				this.showMessage(`${item.name} broke!`);
 			}
 		}
 	}
 
 	/** Show a floating message on screen */
-	private _showMessage(text: string) {
+	showMessage(text: string) {
 		if (this._messageText) {
 			this._messageText.destroy();
 		}

apps/manavoxel/apps/web/src/lib/engine/inventory.svelte.ts

@@ -45,6 +45,7 @@ export const MAX_EQUIPMENT_SLOTS = 1; // Held item
 export class Inventory {
 	slots: (GameItem | null)[] = $state(Array(MAX_INVENTORY_SLOTS).fill(null));
 	heldSlot: number = $state(-1); // -1 = nothing held
+	gold: number = $state(0);
 
 	/** Called when an item is added to inventory */
 	onPickup: ((item: GameItem) => void) | null = null;
@@ -81,6 +82,11 @@ export class Inventory {
 		this.heldSlot = this.heldSlot === slot ? -1 : slot;
 	}
 
+	/** Check if an item with the given ID is in inventory */
+	hasItem(itemId: string): boolean {
+		return this.slots.some((s) => s !== null && s.id === itemId);
+	}
+
 	/** Check if inventory is full */
 	get isFull(): boolean {
 		return this.slots.every((s) => s !== null);

apps/manavoxel/apps/web/src/routes/+page.svelte

@@ -10,7 +10,13 @@
 	import TriggerEditor from '$lib/editor/trigger-editor.svelte';
 	import { Inventory, createItem, type GameItem } from '$lib/engine/inventory.svelte';
 	import { gameStore } from '$lib/data/local-store';
-	import { MERCHANT_OFFERS, rollLoot, type MerchantOffer, type LootDrop } from '$lib/engine/dialog';
+	import {
+		MERCHANT_OFFERS,
+		rollLoot,
+		rollGold,
+		type MerchantOffer,
+		type LootDrop,
+	} from '$lib/engine/dialog';
 	import {
 		loadWorld,
 		getAllWorlds,
@@ -130,6 +136,7 @@
 		if (savedInventory.heldSlot >= 0) {
 			inventory.heldSlot = savedInventory.heldSlot;
 		}
+		inventory.gold = savedInventory.gold;
 		itemCounter = savedItems.length;
 
 		const e = new GameEngine(canvasContainer, worldData ?? undefined);
@@ -138,8 +145,13 @@
 		engine = e;
 		loading = false;
 
-		// Loot drops when NPCs die
+		// Gold + loot drops when NPCs die
 		e.onNpcDeath = (npcX, npcY, behavior) => {
+			const gold = rollGold(behavior);
+			if (gold > 0) {
+				inventory.gold += gold;
+				e.showMessage(`+${gold} gold`);
+			}
 			const loot = rollLoot(behavior);
 			if (loot) {
 				groundItems = [...groundItems, { x: npcX, y: npcY, loot }];
@@ -235,7 +247,7 @@
 				}
 				engine.destroy();
 			}
-			saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot);
+			saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot, inventory.gold);
 			if (keydownHandler) window.removeEventListener('keydown', keydownHandler);
 		};
 	});
@@ -278,6 +290,9 @@
 					<div class="rounded-lg bg-gray-800/80 px-3 py-1.5 text-xs text-gray-300 backdrop-blur">
 						HP: {engine.player.hp}/{engine.player.maxHp}
 					</div>
+					<div class="rounded-lg bg-gray-800/80 px-3 py-1.5 text-xs text-yellow-400 backdrop-blur">
+						{inventory.gold}g
+					</div>
 					<div
 						class="rounded-lg px-3 py-1.5 text-xs backdrop-blur {isNight
 							? 'bg-indigo-900/80 text-indigo-300'
@@ -433,7 +448,7 @@
 					{inventory}
 					onDrop={async (slot) => {
 						inventory.removeItem(slot);
-						await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot);
+						await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot, inventory.gold);
 					}}
 					onInspect={(item) => {
 						editingItem = item;
@@ -591,8 +606,10 @@
 							</div>
 							<button
 								class="rounded-lg bg-emerald-600 px-3 py-1.5 text-xs text-white hover:bg-emerald-500 disabled:opacity-30"
-								disabled={inventory.isFull}
+								disabled={inventory.isFull || inventory.gold < offer.cost}
 								onclick={async () => {
+									if (inventory.gold < offer.cost) return;
+									inventory.gold -= offer.cost;
 									const item = createItem(offer.name, generateTradeSprite(), {
 										damage: offer.damage,
 										range: offer.range,
@@ -608,11 +625,17 @@
 									if (slot >= 0) {
 										inventory.selectSlot(slot);
 										await saveItem(item);
-										await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot);
+										await saveInventory(
+											PLAYER_ID,
+											inventory.slots,
+											inventory.heldSlot,
+											inventory.gold
+										);
 									}
 								}}
 							>
-								{inventory.isFull ? 'Full' : 'Buy'}
+								{#if inventory.isFull}Full{:else if inventory.gold < offer.cost}Need {offer.cost}g{:else}Buy
+									({offer.cost}g){/if}
 							</button>
 						</div>
 					{/each}
@@ -647,7 +670,7 @@
 						});
 						inventory.addItem(item);
 						await saveItem(item);
-						await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot);
+						await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot, inventory.gold);
 						groundItems = groundItems.filter((g) => g !== nearby);
 					}}
 				>
@@ -671,7 +694,7 @@
 					}
 					// Persist item and inventory to IndexedDB
 					await saveItem(item);
-					await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot);
+					await saveInventory(PLAYER_ID, inventory.slots, inventory.heldSlot, inventory.gold);
 					showSpriteEditor = false;
 				}}
 				onClose={() => (showSpriteEditor = false)}

apps/manavoxel/packages/shared/src/types.ts

@@ -130,10 +130,7 @@ export interface Item {
 	resolution: number; // 0.01 for detail items
 	properties: ItemProperties;
 	behavior: TriggerAction[];
-	script?: string;
-	wasmBinary?: Uint8Array;
 	rarity: Rarity;
-	capabilities: string[];
 	isPublished: boolean;
 	createdAt?: string;
 	updatedAt?: string;
@@ -153,52 +150,3 @@ export interface InventorySlot {
 	updatedAt?: string;
 	deletedAt?: string;
 }
-
-// ─── Network Protocol ───────────────────────────────────────
-
-export type ClientMessage =
-	| { type: 'join'; worldId: string; areaId: string }
-	| { type: 'move'; x: number; y: number; direction: number }
-	| { type: 'setPixel'; x: number; y: number; floor: number; material: number }
-	| { type: 'useItem'; itemId: string; targetX: number; targetY: number }
-	| { type: 'enterPortal'; portalId: string }
-	| { type: 'chat'; message: string }
-	| { type: 'ping' };
-
-export type ServerMessage =
-	| { type: 'welcome'; playerId: string; areaState: Area; players: PlayerState[] }
-	| { type: 'playerJoin'; player: PlayerState }
-	| { type: 'playerLeave'; playerId: string }
-	| { type: 'playerMove'; playerId: string; x: number; y: number; direction: number }
-	| {
-			type: 'pixelChanged';
-			x: number;
-			y: number;
-			floor: number;
-			material: number;
-			playerId: string;
-	  }
-	| { type: 'itemUsed'; playerId: string; itemId: string; effects: Effect[] }
-	| { type: 'areaTransition'; areaId: string; areaState: Area; players: PlayerState[] }
-	| { type: 'chat'; playerId: string; name: string; message: string }
-	| { type: 'error'; message: string }
-	| { type: 'pong' };
-
-export interface PlayerState {
-	id: string;
-	name: string;
-	x: number;
-	y: number;
-	floor: number;
-	direction: number; // 0=up, 1=right, 2=down, 3=left
-	heldItemId?: string;
-	hp: number;
-	maxHp: number;
-}
-
-export interface Effect {
-	type: 'damage' | 'heal' | 'particle' | 'sound' | 'pixelDestroy';
-	x: number;
-	y: number;
-	params: Record<string, unknown>;
-}