📝 update changelog for event-queue and action log

Crops, tree seedlings, and tile recovery no longer iterate all entries
every frame. Each event stores an absolute gameTime timestamp (growsAt).
A sorted priority queue is drained each tick — only due items are touched.

WorldState now tracks gameTime (ms); stateManager.advanceTime(delta)
increments it each frame. Save version bumped 5→6 with migration.

Action log ring buffer (15 entries) added to LocalAdapter; shown in
the F3 debug panel under "Last Actions".

Closes #36
Closes #37

CHANGELOG.md

@@ -7,6 +7,12 @@ Format follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [Unreleased]
 
+### Performance
+- **Event-queue timers** (Issue #36): crops, tree seedlings, and tile-recovery events now use a sorted priority queue with absolute `gameTime` timestamps instead of per-frame countdown iteration — O(due items) per tick instead of O(total items); `WorldState.gameTime` tracks the in-game clock; save migrated from v5 to v6
+
+### Added
+- **Action log in F3 debug panel** (Issue #37): last 15 actions dispatched through the adapter are shown in the F3 overlay under "Last Actions"; ring buffer maintained in `LocalAdapter`
+
 ### Fixed
 - **Y-based depth sorting** (Issue #31): trees, rocks, seedlings and buildings now use `tileY + 5` as depth instead of fixed values — objects lower on screen always render in front of objects above them, regardless of spawn order; build ghost moved to depth 1000
 - **Nisse always visible** (Issue #33): Nisse sprites fixed at depth 900, always rendered above world objects

src/NetworkAdapter.ts

@@ -8,12 +8,42 @@ export interface NetworkAdapter {
   onAction?: (action: GameAction) => void
 }
 
+const ACTION_LOG_SIZE = 15
+
 /** Singleplayer: apply actions immediately and synchronously */
 export class LocalAdapter implements NetworkAdapter {
   onAction?: (action: GameAction) => void
 
+  /** Ring-buffer of the last ACTION_LOG_SIZE dispatched action summaries. */
+  private _actionLog: string[] = []
+
   send(action: GameAction): void {
     stateManager.apply(action)
+    this._recordAction(action)
     this.onAction?.(action)
   }
+
+  /** Returns a copy of the recent action log (oldest first). */
+  getActionLog(): readonly string[] { return this._actionLog }
+
+  /**
+   * Appends a short summary of the action to the ring-buffer.
+   * @param action - The dispatched game action
+   */
+  private _recordAction(action: GameAction): void {
+    let entry = action.type
+    if ('tileX' in action && 'tileY' in action)
+      entry += ` (${(action as any).tileX},${(action as any).tileY})`
+    else if ('villagerId' in action)
+      entry += ` v=…${(action as any).villagerId.slice(-4)}`
+    else if ('resourceId' in action)
+      entry += ` r=…${(action as any).resourceId.slice(-4)}`
+    else if ('cropId' in action)
+      entry += ` c=…${(action as any).cropId.slice(-4)}`
+    else if ('seedlingId' in action)
+      entry += ` s=…${(action as any).seedlingId.slice(-4)}`
+
+    if (this._actionLog.length >= ACTION_LOG_SIZE) this._actionLog.shift()
+    this._actionLog.push(entry)
+  }
 }

src/StateManager.ts

@@ -2,15 +2,42 @@ import { SAVE_KEY, WORLD_TILES, CROP_CONFIGS, TREE_SEEDLING_STAGE_MS, TILE_RECOV
 import type { GameStateData, GameAction, PlayerState, WorldState, ItemId } from './types'
 import { TileType } from './types'
 
+// ─── Internal queue entry types ───────────────────────────────────────────────
+
+/** Scheduled crop-growth entry. Two entries are created per stage (normal + watered path). */
+interface CropEntry {
+  id: string
+  fireAt: number
+  expectedStage: number
+  /** If true this entry only fires when crop.watered === true. */
+  wateredPath: boolean
+}
+
+/** Scheduled seedling-growth entry. One entry per stage. */
+interface SeedlingEntry {
+  id: string
+  fireAt: number
+  expectedStage: number
+}
+
+/** Scheduled tile-recovery entry. One entry per tile. */
+interface RecoveryEntry {
+  key: string
+  fireAt: number
+}
+
+// ─── State factories ───────────────────────────────────────────────────────────
+
 const DEFAULT_PLAYER: PlayerState = {
   id: 'player1',
   x: 8192, y: 8192,
-  inventory: {},  // empty — seeds now in stockpile
+  inventory: {},
 }
 
 function makeEmptyWorld(seed: number): WorldState {
   return {
     seed,
+    gameTime: 0,
     tiles: new Array(WORLD_TILES * WORLD_TILES).fill(3),
     resources: {},
     buildings: {},
@@ -25,21 +52,164 @@ function makeEmptyWorld(seed: number): WorldState {
 
 function makeDefaultState(): GameStateData {
   return {
-    version: 5,
+    version: 6,
     world: makeEmptyWorld(Math.floor(Math.random() * 999999)),
     player: { ...DEFAULT_PLAYER, inventory: { ...DEFAULT_PLAYER.inventory } },
   }
 }
 
+// ─── StateManager ─────────────────────────────────────────────────────────────
+
 class StateManager {
   private state: GameStateData
 
+  // In-memory event queues (not persisted; rebuilt from state on load).
+  private cropQueue:     CropEntry[]     = []
+  private seedlingQueue: SeedlingEntry[] = []
+  private recoveryQueue: RecoveryEntry[] = []
+
   constructor() {
     this.state = this.load() ?? makeDefaultState()
+    this.rebuildQueues()
   }
 
   getState(): Readonly<GameStateData> { return this.state }
 
+  /** Returns the current accumulated in-game time in milliseconds. */
+  getGameTime(): number { return this.state.world.gameTime }
+
+  /**
+   * Advances the in-game clock by delta milliseconds.
+   * Must be called once per frame before any tick methods.
+   * @param delta - Frame delta in milliseconds
+   */
+  advanceTime(delta: number): void {
+    this.state.world.gameTime += delta
+  }
+
+  // ─── Queue helpers ──────────────────────────────────────────────────────────
+
+  /**
+   * Inserts an entry into a sorted queue in ascending fireAt order.
+   * Uses binary search for O(log n) position find; O(n) splice insert.
+   */
+  private static insertSorted<T extends { fireAt: number }>(queue: T[], entry: T): void {
+    let lo = 0, hi = queue.length
+    while (lo < hi) {
+      const mid = (lo + hi) >>> 1
+      if (queue[mid].fireAt <= entry.fireAt) lo = mid + 1
+      else hi = mid
+    }
+    queue.splice(lo, 0, entry)
+  }
+
+  /** Enqueues both growth entries (normal + watered path) for a crop's current stage. */
+  private enqueueCropStage(id: string, expectedStage: number, growsAt: number, growsAtWatered: number): void {
+    StateManager.insertSorted(this.cropQueue, { id, fireAt: growsAt,        expectedStage, wateredPath: false })
+    StateManager.insertSorted(this.cropQueue, { id, fireAt: growsAtWatered, expectedStage, wateredPath: true  })
+  }
+
+  /**
+   * Rebuilds all three event queues from the persisted state.
+   * Called once after construction or load.
+   */
+  private rebuildQueues(): void {
+    this.cropQueue     = []
+    this.seedlingQueue = []
+    this.recoveryQueue = []
+
+    for (const crop of Object.values(this.state.world.crops)) {
+      if (crop.stage >= crop.maxStage) continue
+      this.enqueueCropStage(crop.id, crop.stage, crop.growsAt, crop.growsAtWatered)
+    }
+
+    for (const s of Object.values(this.state.world.treeSeedlings)) {
+      if (s.stage < 2) {
+        StateManager.insertSorted(this.seedlingQueue, { id: s.id, fireAt: s.growsAt, expectedStage: s.stage })
+      }
+    }
+
+    for (const [key, fireAt] of Object.entries(this.state.world.tileRecovery)) {
+      StateManager.insertSorted(this.recoveryQueue, { key, fireAt })
+    }
+  }
+
+  // ─── Tick methods ──────────────────────────────────────────────────────────
+
+  /**
+   * Drains the crop queue up to the current gameTime.
+   * Returns IDs of crops that advanced a stage this frame.
+   */
+  tickCrops(): string[] {
+    const now = this.state.world.gameTime
+    const advanced: string[] = []
+
+    while (this.cropQueue.length > 0 && this.cropQueue[0].fireAt <= now) {
+      const entry = this.cropQueue.shift()!
+      const crop = this.state.world.crops[entry.id]
+      if (!crop || crop.stage !== entry.expectedStage) continue  // already removed or stale stage
+      if (entry.wateredPath && !crop.watered) continue           // fast-path skipped: not watered
+
+      crop.stage++
+      advanced.push(crop.id)
+
+      if (crop.stage < crop.maxStage) {
+        const cfg = CROP_CONFIGS[crop.kind]
+        crop.growsAt        = now + cfg.stageTimeMs
+        crop.growsAtWatered = now + cfg.stageTimeMs / 2
+        this.enqueueCropStage(crop.id, crop.stage, crop.growsAt, crop.growsAtWatered)
+      }
+    }
+    return advanced
+  }
+
+  /**
+   * Drains the seedling queue up to the current gameTime.
+   * Returns IDs of seedlings that advanced a stage this frame.
+   */
+  tickSeedlings(): string[] {
+    const now = this.state.world.gameTime
+    const advanced: string[] = []
+
+    while (this.seedlingQueue.length > 0 && this.seedlingQueue[0].fireAt <= now) {
+      const entry = this.seedlingQueue.shift()!
+      const s = this.state.world.treeSeedlings[entry.id]
+      if (!s || s.stage !== entry.expectedStage) continue  // removed or stale
+
+      s.stage = Math.min(s.stage + 1, 2)
+      advanced.push(s.id)
+
+      if (s.stage < 2) {
+        s.growsAt = now + TREE_SEEDLING_STAGE_MS
+        StateManager.insertSorted(this.seedlingQueue, { id: s.id, fireAt: s.growsAt, expectedStage: s.stage })
+      }
+    }
+    return advanced
+  }
+
+  /**
+   * Drains the tile-recovery queue up to the current gameTime.
+   * Returns keys ("tileX,tileY") of tiles that have reverted to GRASS.
+   */
+  tickTileRecovery(): string[] {
+    const now = this.state.world.gameTime
+    const recovered: string[] = []
+
+    while (this.recoveryQueue.length > 0 && this.recoveryQueue[0].fireAt <= now) {
+      const entry = this.recoveryQueue.shift()!
+      const fireAt = this.state.world.tileRecovery[entry.key]
+      // Skip if the entry was superseded (tile re-planted, resetting its fireAt)
+      if (fireAt === undefined || fireAt > now) continue
+      delete this.state.world.tileRecovery[entry.key]
+      recovered.push(entry.key)
+      const [tx, ty] = entry.key.split(',').map(Number)
+      this.state.world.tiles[ty * WORLD_TILES + tx] = TileType.GRASS
+    }
+    return recovered
+  }
+
+  // ─── State mutations ───────────────────────────────────────────────────────
+
   apply(action: GameAction): void {
     const s = this.state
     const w = s.world
@@ -66,7 +236,6 @@ class StateManager {
         w.buildings[action.building.id] = action.building
         for (const [k, v] of Object.entries(action.costs))
           w.stockpile[k as ItemId] = Math.max(0, (w.stockpile[k as ItemId] ?? 0) - (v ?? 0))
-        // Automatically create an empty forester zone when a forester hut is placed
         if (action.building.kind === 'forester_hut') {
           w.foresterZones[action.building.id] = { buildingId: action.building.id, tiles: [] }
         }
@@ -74,7 +243,6 @@ class StateManager {
       }
 
       case 'REMOVE_BUILDING':
-        // Remove associated forester zone when the hut is demolished
         if (w.buildings[action.buildingId]?.kind === 'forester_hut') {
           delete w.foresterZones[action.buildingId]
         }
@@ -90,22 +258,24 @@ class StateManager {
         w.crops[action.crop.id] = { ...action.crop }
         const have = w.stockpile[action.seedItem] ?? 0
         w.stockpile[action.seedItem] = Math.max(0, have - 1)
+        // Enqueue growth timers for both normal and watered paths
+        this.enqueueCropStage(action.crop.id, 0, action.crop.growsAt, action.crop.growsAtWatered)
         break
       }
 
       case 'WATER_CROP': {
         const c = w.crops[action.cropId]; if (c) c.watered = true; break
+        // No queue change needed — the wateredPath entry was enqueued at planting time
       }
 
       case 'HARVEST_CROP': {
         delete w.crops[action.cropId]
         for (const [k, v] of Object.entries(action.rewards))
           w.stockpile[k as ItemId] = (w.stockpile[k as ItemId] ?? 0) + (v ?? 0)
+        // Stale queue entries will be skipped automatically (crop no longer exists)
         break
       }
 
-      // ── Villager actions ──────────────────────────────────────────────────
-
       case 'SPAWN_VILLAGER':
         w.villagers[action.villager.id] = { ...action.villager }; break
 
@@ -163,22 +333,30 @@ class StateManager {
       case 'PLANT_TREE_SEED': {
         w.treeSeedlings[action.seedling.id] = { ...action.seedling }
         w.stockpile.tree_seed = Math.max(0, (w.stockpile.tree_seed ?? 0) - 1)
-        // Cancel any tile recovery on this tile
         delete w.tileRecovery[`${action.seedling.tileX},${action.seedling.tileY}`]
+        // Enqueue growth timer
+        StateManager.insertSorted(this.seedlingQueue, {
+          id: action.seedling.id, fireAt: action.seedling.growsAt, expectedStage: 0
+        })
         break
       }
 
       case 'REMOVE_TREE_SEEDLING':
         delete w.treeSeedlings[action.seedlingId]
+        // Stale queue entries will be skipped automatically
         break
 
       case 'SPAWN_RESOURCE':
         w.resources[action.resource.id] = { ...action.resource }
         break
 
-      case 'TILE_RECOVERY_START':
-        w.tileRecovery[`${action.tileX},${action.tileY}`] = TILE_RECOVERY_MS
+      case 'TILE_RECOVERY_START': {
+        const fireAt = w.gameTime + TILE_RECOVERY_MS
+        const key = `${action.tileX},${action.tileY}`
+        w.tileRecovery[key] = fireAt
+        StateManager.insertSorted(this.recoveryQueue, { key, fireAt })
         break
+      }
 
       case 'FORESTER_ZONE_UPDATE': {
         const zone = w.foresterZones[action.buildingId]
@@ -188,60 +366,7 @@ class StateManager {
     }
   }
 
-  tickCrops(delta: number): string[] {
-    const advanced: string[] = []
-    for (const crop of Object.values(this.state.world.crops)) {
-      if (crop.stage >= crop.maxStage) continue
-      crop.stageTimerMs -= delta * (crop.watered ? 2 : 1)
-      if (crop.stageTimerMs <= 0) {
-        crop.stage = Math.min(crop.stage + 1, crop.maxStage)
-        crop.stageTimerMs = CROP_CONFIGS[crop.kind].stageTimeMs
-        advanced.push(crop.id)
-      }
-    }
-    return advanced
-  }
-
-  /**
-   * Advances all tree-seedling growth timers.
-   * Returns IDs of seedlings that have reached stage 2 (ready to mature into a tree).
-   * @param delta - Frame delta in milliseconds
-   * @returns Array of seedling IDs that are now mature
-   */
-  tickSeedlings(delta: number): string[] {
-    const advanced: string[] = []
-    for (const s of Object.values(this.state.world.treeSeedlings)) {
-      s.stageTimerMs -= delta
-      if (s.stageTimerMs <= 0) {
-        s.stage = Math.min(s.stage + 1, 2)
-        s.stageTimerMs = TREE_SEEDLING_STAGE_MS
-        advanced.push(s.id)
-      }
-    }
-    return advanced
-  }
-
-  /**
-   * Ticks tile-recovery timers.
-   * Returns keys ("tileX,tileY") of tiles that have now recovered back to GRASS.
-   * @param delta - Frame delta in milliseconds
-   * @returns Array of recovered tile keys
-   */
-  tickTileRecovery(delta: number): string[] {
-    const recovered: string[] = []
-    const rec = this.state.world.tileRecovery
-    for (const key of Object.keys(rec)) {
-      rec[key] -= delta
-      if (rec[key] <= 0) {
-        delete rec[key]
-        recovered.push(key)
-        // Update tiles array directly (DARK_GRASS → GRASS)
-        const [tx, ty] = key.split(',').map(Number)
-        this.state.world.tiles[ty * WORLD_TILES + tx] = TileType.GRASS
-      }
-    }
-    return recovered
-  }
+  // ─── Persistence ───────────────────────────────────────────────────────────
 
   save(): void {
     try { localStorage.setItem(SAVE_KEY, JSON.stringify(this.state)) } catch (_) {}
@@ -252,20 +377,40 @@ class StateManager {
       const raw = localStorage.getItem(SAVE_KEY)
       if (!raw) return null
       const p = JSON.parse(raw) as GameStateData
-      if (p.version !== 5) return null
+
+      // ── Migrate v5 → v6: countdown timers → absolute gameTime timestamps ──
+      if ((p.version as number) === 5) {
+        p.world.gameTime = 0
+        for (const crop of Object.values(p.world.crops)) {
+          const old = crop as any
+          const ms = old.stageTimerMs ?? CROP_CONFIGS[crop.kind]?.stageTimeMs ?? 20_000
+          crop.growsAt        = ms
+          crop.growsAtWatered = ms / 2
+          delete old.stageTimerMs
+        }
+        for (const s of Object.values(p.world.treeSeedlings)) {
+          const old = s as any
+          s.growsAt = old.stageTimerMs ?? TREE_SEEDLING_STAGE_MS
+          delete old.stageTimerMs
+        }
+        // tileRecovery values were remaining-ms countdowns; with gameTime=0 they equal fireAt directly
+        p.version = 6
+      }
+
+      if (p.version !== 6) return null
+
       if (!p.world.crops)          p.world.crops          = {}
       if (!p.world.villagers)      p.world.villagers      = {}
       if (!p.world.stockpile)      p.world.stockpile      = {}
       if (!p.world.treeSeedlings)  p.world.treeSeedlings  = {}
       if (!p.world.tileRecovery)   p.world.tileRecovery   = {}
       if (!p.world.foresterZones)  p.world.foresterZones  = {}
-      // Reset in-flight AI states to idle on load so runtime timers start fresh
+      if (!p.world.gameTime)       p.world.gameTime       = 0
+
       for (const v of Object.values(p.world.villagers)) {
         if (v.aiState === 'walking' || v.aiState === 'working') v.aiState = 'idle'
-        // Migrate older saves that don't have the forester priority
         if (typeof (v.priorities as any).forester === 'undefined') v.priorities.forester = 4
       }
-      // Rebuild forester zones for huts that predate the foresterZones field
       for (const b of Object.values(p.world.buildings)) {
         if (b.kind === 'forester_hut' && !p.world.foresterZones[b.id]) {
           p.world.foresterZones[b.id] = { buildingId: b.id, tiles: [] }
@@ -278,6 +423,7 @@ class StateManager {
   reset(): void {
     localStorage.removeItem(SAVE_KEY)
     this.state = makeDefaultState()
+    this.rebuildQueues()
   }
 }
 

src/scenes/GameScene.ts

@@ -46,7 +46,7 @@ export class GameScene extends Phaser.Scene {
     this.villagerSystem.init(this.resourceSystem, this.farmingSystem)
     this.treeSeedlingSystem  = new TreeSeedlingSystem(this, this.adapter, this.worldSystem)
     this.foresterZoneSystem  = new ForesterZoneSystem(this, this.adapter)
-    this.debugSystem         = new DebugSystem(this, this.villagerSystem, this.worldSystem)
+    this.debugSystem         = new DebugSystem(this, this.villagerSystem, this.worldSystem, this.adapter)
 
     this.worldSystem.create()
     this.renderPersistentObjects()
@@ -145,6 +145,9 @@ export class GameScene extends Phaser.Scene {
   update(_time: number, delta: number): void {
     if (this.menuOpen) return
 
+    // Advance the in-game clock first so all tick methods see the updated time
+    stateManager.advanceTime(delta)
+
     this.cameraSystem.update(delta)
 
     this.resourceSystem.update(delta)
@@ -153,8 +156,8 @@ export class GameScene extends Phaser.Scene {
     this.villagerSystem.update(delta)
     this.debugSystem.update()
 
-    // Tick tile-recovery timers; refresh canvas for any tiles that reverted to GRASS
-    const recovered = stateManager.tickTileRecovery(delta)
+    // Drain tile-recovery queue; refresh canvas for any tiles that reverted to GRASS
+    const recovered = stateManager.tickTileRecovery()
     for (const key of recovered) {
       const [tx, ty] = key.split(',').map(Number)
       this.worldSystem.refreshTerrainTile(tx, ty, TileType.GRASS)

src/scenes/UIScene.ts

@@ -463,6 +463,9 @@ export class UIScene extends Phaser.Scene {
       '',
       `Paths: ${data.activePaths} (cyan lines in world)`,
       '',
+      '── Last Actions ───────────────',
+      ...(data.actionLog.length > 0 ? data.actionLog : ['—']),
+      '',
       '[F3] close',
     ])
   }

src/systems/DebugSystem.ts

@@ -2,6 +2,7 @@ import Phaser from 'phaser'
 import { TILE_SIZE } from '../config'
 import { TileType } from '../types'
 import { stateManager } from '../StateManager'
+import type { LocalAdapter } from '../NetworkAdapter'
 import type { VillagerSystem } from './VillagerSystem'
 import type { WorldSystem } from './WorldSystem'
 
@@ -18,6 +19,8 @@ export interface DebugData {
   nisseByState: { idle: number; walking: number; working: number; sleeping: number }
   jobsByType:   { chop: number; mine: number; farm: number }
   activePaths:  number
+  /** Recent actions dispatched through the adapter (newest last). */
+  actionLog: readonly string[]
 }
 
 /** Human-readable names for TileType enum values. */
@@ -39,6 +42,7 @@ export class DebugSystem {
   private scene:          Phaser.Scene
   private villagerSystem: VillagerSystem
   private worldSystem:    WorldSystem
+  private adapter:        LocalAdapter
   private pathGraphics!:  Phaser.GameObjects.Graphics
   private active = false
 
@@ -46,11 +50,13 @@ export class DebugSystem {
    * @param scene          - The Phaser scene this system belongs to
    * @param villagerSystem - Used to read active paths for visualization
    * @param worldSystem    - Used to read tile types under the mouse
+   * @param adapter        - Used to read the recent action log
    */
-  constructor(scene: Phaser.Scene, villagerSystem: VillagerSystem, worldSystem: WorldSystem) {
+  constructor(scene: Phaser.Scene, villagerSystem: VillagerSystem, worldSystem: WorldSystem, adapter: LocalAdapter) {
     this.scene          = scene
     this.villagerSystem = villagerSystem
     this.worldSystem    = worldSystem
+    this.adapter        = adapter
   }
 
   /**
@@ -159,6 +165,7 @@ export class DebugSystem {
       nisseByState,
       jobsByType,
       activePaths:    this.villagerSystem.getActivePaths().length,
+      actionLog:      this.adapter.getActionLog(),
     }
   }
 }

src/systems/FarmingSystem.ts

@@ -74,8 +74,8 @@ export class FarmingSystem {
       this.setTool(TOOL_CYCLE[(idx + 1) % TOOL_CYCLE.length])
     }
 
-    // Tick crop growth
-    const leveled = stateManager.tickCrops(delta)
+    // Drain crop growth queue (no delta — gameTime is advanced by GameScene)
+    const leveled = stateManager.tickCrops()
     for (const id of leveled) this.refreshCropSprite(id)
   }
 
@@ -151,11 +151,13 @@ export class FarmingSystem {
     }
 
     const cfg = CROP_CONFIGS[kind]
+    const now = stateManager.getGameTime()
     const crop: CropState = {
       id: `crop_${tileX}_${tileY}_${Date.now()}`,
       tileX, tileY, kind,
       stage: 0, maxStage: cfg.stages,
-      stageTimerMs: cfg.stageTimeMs,
+      growsAt:        now + cfg.stageTimeMs,
+      growsAtWatered: now + cfg.stageTimeMs / 2,
       watered: tile === TileType.WATERED_SOIL,
     }
     this.adapter.send({ type: 'PLANT_CROP', crop, seedItem })

src/systems/TreeSeedlingSystem.ts

@@ -38,7 +38,8 @@ export class TreeSeedlingSystem {
    * @param delta - Frame delta in milliseconds
    */
   update(delta: number): void {
-    const advanced = stateManager.tickSeedlings(delta)
+    // Drain seedling growth queue (no delta — gameTime is advanced by GameScene)
+    const advanced = stateManager.tickSeedlings()
     for (const id of advanced) {
       const state = stateManager.getState()
       const seedling = state.world.treeSeedlings[id]
@@ -91,7 +92,7 @@ export class TreeSeedlingSystem {
     const seedling: TreeSeedlingState = {
       id, tileX, tileY,
       stage: 0,
-      stageTimerMs: TREE_SEEDLING_STAGE_MS,
+      growsAt: stateManager.getGameTime() + TREE_SEEDLING_STAGE_MS,
       underlyingTile,
     }
 

src/types.ts

@@ -90,7 +90,11 @@ export interface CropState {
   kind: CropKind
   stage: number
   maxStage: number
-  stageTimerMs: number
+  /** gameTime (ms) when this stage fires at normal (unwatered) speed. */
+  growsAt: number
+  /** gameTime (ms) when this stage fires if the crop is watered (half normal time).
+   *  Both entries are enqueued at plant/stage-advance time; the stale one is skipped. */
+  growsAtWatered: number
   watered: boolean
 }
 
@@ -107,8 +111,8 @@ export interface TreeSeedlingState {
   tileY: number
   /** Growth stage: 0 = sprout, 1 = sapling, 2 = mature (converts to resource). */
   stage: number
-  /** Time remaining until next stage advance, in milliseconds. */
-  stageTimerMs: number
+  /** gameTime (ms) when this seedling advances to the next stage. */
+  growsAt: number
   /** The tile type that was under the seedling when planted (GRASS or DARK_GRASS). */
   underlyingTile: TileType
 }
@@ -125,6 +129,8 @@ export interface ForesterZoneState {
 
 export interface WorldState {
   seed: number
+  /** Accumulated in-game time in milliseconds. Used as the clock for all event-queue timers. */
+  gameTime: number
   tiles: number[]
   resources: Record<string, ResourceNodeState>
   buildings: Record<string, BuildingState>
@@ -134,8 +140,8 @@ export interface WorldState {
   /** Planted tree seedlings, keyed by ID. */
   treeSeedlings: Record<string, TreeSeedlingState>
   /**
-   * Recovery timers for DARK_GRASS tiles, keyed by "tileX,tileY".
-   * Value is remaining milliseconds until the tile reverts to GRASS.
+   * Tile recovery fire-times, keyed by "tileX,tileY".
+   * Value is the gameTime (ms) at which the tile reverts to GRASS.
    */
   tileRecovery: Record<string, number>
   /** Forester zone definitions, keyed by forester_hut building ID. */