✨ add file logging via Vite middleware to ZoomTestScene

Vite dev server gets a /api/log middleware (POST appends to
game-test.log, DELETE clears it). ZoomTestScene writes a zoom event
with before/after state on every scroll, plus a full snapshot every
2 seconds. Log entries are newline-delimited JSON.

src/test/ZoomTestScene.ts

@@ -1,17 +1,19 @@
 import Phaser from 'phaser'
 import { TILE_SIZE } from '../config'
 
-const GRID_TILES    = 50     // world size in tiles
-const MIN_ZOOM      = 0.25
-const MAX_ZOOM      = 4.0
-const ZOOM_STEP     = 0.1
-const MARKER_EVERY  = 5      // small crosshair every N tiles
-const LABEL_EVERY   = 10     // coordinate label every N tiles
-const CAMERA_SPEED  = 400    // px/s
+const GRID_TILES       = 50     // world size in tiles
+const MIN_ZOOM         = 0.25
+const MAX_ZOOM         = 4.0
+const ZOOM_STEP        = 0.1
+const MARKER_EVERY     = 5      // small crosshair every N tiles
+const LABEL_EVERY      = 10     // coordinate label every N tiles
+const CAMERA_SPEED     = 400    // px/s
+const SNAPSHOT_EVERY   = 2000   // ms between periodic log snapshots
 
 /**
  * First test scene: observes pure Phaser default zoom behavior.
  * No custom scroll compensation — cam.setZoom() only, zoom anchors to camera center.
+ * Logs zoom events and periodic snapshots to /api/log (written to game-test.log).
  *
  * Controls: Scroll wheel to zoom, WASD / Arrow keys to pan.
  */
@@ -27,12 +29,17 @@ export class ZoomTestScene extends Phaser.Scene {
     a:     Phaser.Input.Keyboard.Key
     d:     Phaser.Input.Keyboard.Key
   }
+  private snapshotTimer = 0
 
   constructor() {
     super({ key: 'ZoomTest' })
   }
 
   create(): void {
+    // Clear log file at scene start
+    fetch('/api/log', { method: 'DELETE' })
+    this.writeLog('scene_start', { tileSize: TILE_SIZE, gridTiles: GRID_TILES })
+
     this.drawGrid()
     this.setupCamera()
     this.setupInput()
@@ -111,6 +118,7 @@ export class ZoomTestScene extends Phaser.Scene {
   /**
    * Registers scroll wheel zoom and stores keyboard key references.
    * Zoom uses cam.setZoom() only — pure Phaser default, anchors to camera center.
+   * Each zoom event is logged immediately with before/after state.
    */
   private setupInput(): void {
     const cam = this.cameras.main
@@ -128,13 +136,42 @@ export class ZoomTestScene extends Phaser.Scene {
     }
 
     this.input.on('wheel', (
-      _ptr:  Phaser.Input.Pointer,
+      ptr:   Phaser.Input.Pointer,
       _objs: unknown,
       _dx:   number,
       dy:    number
     ) => {
+      const zoomBefore  = cam.zoom
+      const scrollXBefore = cam.scrollX
+      const scrollYBefore = cam.scrollY
+
       const newZoom = Phaser.Math.Clamp(cam.zoom - Math.sign(dy) * ZOOM_STEP, MIN_ZOOM, MAX_ZOOM)
       cam.setZoom(newZoom)
+
+      // Log after Phaser has applied the zoom (next microtask so values are updated)
+      setTimeout(() => {
+        this.writeLog('zoom', {
+          direction:     dy > 0 ? 'out' : 'in',
+          zoomBefore:    +zoomBefore.toFixed(4),
+          zoomAfter:     +cam.zoom.toFixed(4),
+          scrollX_before: +scrollXBefore.toFixed(2),
+          scrollY_before: +scrollYBefore.toFixed(2),
+          scrollX_after:  +cam.scrollX.toFixed(2),
+          scrollY_after:  +cam.scrollY.toFixed(2),
+          scrollX_delta:  +(cam.scrollX - scrollXBefore).toFixed(2),
+          scrollY_delta:  +(cam.scrollY - scrollYBefore).toFixed(2),
+          mouseScreen: { x: +ptr.x.toFixed(1), y: +ptr.y.toFixed(1) },
+          mouseWorld:  { x: +ptr.worldX.toFixed(2), y: +ptr.worldY.toFixed(2) },
+          centerWorld_after: {
+            x: +(cam.scrollX + (cam.width  / cam.zoom) / 2).toFixed(2),
+            y: +(cam.scrollY + (cam.height / cam.zoom) / 2).toFixed(2),
+          },
+          vpTiles_after: {
+            w: +((cam.width  / cam.zoom) / TILE_SIZE).toFixed(3),
+            h: +((cam.height / cam.zoom) / TILE_SIZE).toFixed(3),
+          },
+        })
+      }, 0)
     })
   }
 
@@ -157,6 +194,13 @@ export class ZoomTestScene extends Phaser.Scene {
   update(_time: number, delta: number): void {
     this.handleKeyboard(delta)
     this.updateOverlay()
+
+    // Periodic snapshot
+    this.snapshotTimer += delta
+    if (this.snapshotTimer >= SNAPSHOT_EVERY) {
+      this.snapshotTimer = 0
+      this.writeSnapshot()
+    }
   }
 
   /**
@@ -236,4 +280,46 @@ export class ZoomTestScene extends Phaser.Scene {
 
     this.logText.setText(lines)
   }
+
+  /**
+   * Writes a periodic full-state snapshot to the log.
+   */
+  private writeSnapshot(): void {
+    const cam = this.cameras.main
+    const ptr = this.input.activePointer
+    const vpW = cam.width  / cam.zoom
+    const vpH = cam.height / cam.zoom
+
+    this.writeLog('snapshot', {
+      zoom:        +cam.zoom.toFixed(4),
+      scrollX:     +cam.scrollX.toFixed(2),
+      scrollY:     +cam.scrollY.toFixed(2),
+      vpScreen:    { w: cam.width, h: cam.height },
+      vpWorld:     { w: +vpW.toFixed(2), h: +vpH.toFixed(2) },
+      vpTiles:     { w: +((vpW / TILE_SIZE).toFixed(3)), h: +((vpH / TILE_SIZE).toFixed(3)) },
+      centerWorld: {
+        x: +(cam.scrollX + vpW / 2).toFixed(2),
+        y: +(cam.scrollY + vpH / 2).toFixed(2),
+      },
+      mouse: {
+        screen: { x: +ptr.x.toFixed(1), y: +ptr.y.toFixed(1) },
+        world:  { x: +ptr.worldX.toFixed(2), y: +ptr.worldY.toFixed(2) },
+      },
+    })
+  }
+
+  /**
+   * POSTs a structured log entry to the Vite dev server middleware.
+   * Written to game-test.log in the project root.
+   * @param event - Event type label
+   * @param data  - Payload object to serialize as JSON
+   */
+  private writeLog(event: string, data: Record<string, unknown>): void {
+    const entry = JSON.stringify({ t: Date.now(), event, ...data })
+    fetch('/api/log', {
+      method: 'POST',
+      headers: { 'Content-Type': 'text/plain' },
+      body: entry,
+    }).catch(() => { /* swallow if dev server not running */ })
+  }
 }

vite.config.ts

@@ -1,11 +1,39 @@
 import { defineConfig } from 'vite'
 import { resolve } from 'path'
+import fs from 'fs'
+
+const LOG_FILE = resolve(__dirname, 'game-test.log')
 
 export default defineConfig({
   server: {
     port: 3000,
-    host: true
+    host: true,
   },
+  plugins: [
+    {
+      name: 'game-logger',
+      configureServer(server) {
+        server.middlewares.use('/api/log', (req, res) => {
+          if (req.method === 'POST') {
+            let body = ''
+            req.on('data', chunk => { body += chunk })
+            req.on('end', () => {
+              fs.appendFileSync(LOG_FILE, body + '\n', 'utf8')
+              res.writeHead(200)
+              res.end('ok')
+            })
+          } else if (req.method === 'DELETE') {
+            fs.writeFileSync(LOG_FILE, '', 'utf8')
+            res.writeHead(200)
+            res.end('cleared')
+          } else {
+            res.writeHead(405)
+            res.end()
+          }
+        })
+      },
+    },
+  ],
   build: {
     outDir: 'dist',
     assetsInlineLimit: 0,