Add discreet anticheat mechanism for the games

src/app/corne/melon-game.tsx

@@ -30,7 +30,20 @@ function randomTier(min: number, max: number): number {
   return min + Math.floor(Math.random() * (max - min + 1));
 }
 
-export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFinish: (score: number) => void }) {
+export type MelonRunTelemetry = {
+  v: 1;
+  duration_ms: number;
+  actions: number;
+  merges: number;
+};
+
+export function MelonGame({
+  citizens,
+  onFinish,
+}: {
+  citizens: MemberRow[];
+  onFinish: (score: number, run: MelonRunTelemetry) => void;
+}) {
   const containerRef = useRef<HTMLDivElement | null>(null);
   const previewRef = useRef<HTMLDivElement | null>(null);
   const guideLineRef = useRef<HTMLDivElement | null>(null);
@@ -71,6 +84,9 @@ export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFin
   const pendingMergesRef = useRef<PendingMerge[]>([]);
   const mergingBodyIdsRef = useRef(new Set<number>());
   const dangerSinceRef = useRef<number | null>(null);
+  const runStartedAtRef = useRef(Date.now());
+  const dropCountRef = useRef(0);
+  const mergeCountRef = useRef(0);
 
   const spawnPiece = useCallback(
     (tier: number, x: number, y: number): Piece => {
@@ -128,6 +144,10 @@ export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFin
     pendingMergesRef.current = [];
     mergingBodyIdsRef.current.clear();
     dangerSinceRef.current = null;
+    runStartedAtRef.current = Date.now();
+    dropCountRef.current = 0;
+    mergeCountRef.current = 0;
+    lastDropAtRef.current = -Infinity;
     scoreRef.current = 0;
     statusRef.current = "playing";
     const firstNextTier = randomTier(DROP_MIN_TIER, dropMaxTier);
@@ -160,6 +180,7 @@ export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFin
     // incrémente le compteur d'id) : appelé une seule fois ici, jamais
     // depuis l'intérieur du updater de setPieces, qui doit rester pur.
     const dropped = spawnPiece(tier, x, radius + 6);
+    dropCountRef.current += 1;
     setPieces((current) => [...current, dropped]);
 
     // La file glisse d'un cran : ce qui était annoncé en second devient la
@@ -281,6 +302,7 @@ export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFin
         if (!bodyA || !bodyB) continue;
 
         Matter.Composite.remove(engine.world, [bodyA, bodyB]);
+        mergeCountRef.current += 1;
         bodiesRef.current.delete(merge.pieceIdA);
         bodiesRef.current.delete(merge.pieceIdB);
         nodeRefs.current.delete(merge.pieceIdA);
@@ -338,7 +360,12 @@ export function MelonGame({ citizens, onFinish }: { citizens: MemberRow[]; onFin
           } else if (now - dangerSinceRef.current >= GAME_OVER_GRACE_MS) {
             statusRef.current = "dead";
             setStatus("dead");
-            onFinishRef.current(scoreRef.current);
+            onFinishRef.current(scoreRef.current, {
+              v: 1,
+              duration_ms: Math.max(0, Date.now() - runStartedAtRef.current),
+              actions: dropCountRef.current,
+              merges: mergeCountRef.current,
+            });
           }
         } else {
           dangerSinceRef.current = null;