Update app.py

app.py

@@ -241,23 +241,29 @@ def generate_game_code(game_type: str, theme: str, temperature: float, max_new_t
         system_msg = (
             "You are an expert HTML5 game developer. "
             "Write a complete, working, single-file HTML5 game using canvas and vanilla JavaScript. "
-            "CRITICAL RULES: "
-            "1. Track keyboard input using a Set and keydown/keyup event listeners, NEVER document.key. "
-            "2. Implement real gravity: add 0.5 to velY each frame, reset velY=0 on platform landing. "
-            "3. Implement real jump: only when grounded, set velY=-12. "
-            "4. Use new Image() with src='sprite_NAME.png' for every visual asset, max 3 sprites. "
-            "5. Draw images with ctx.drawImage(img, x, y, w, h). "
+            "CRITICAL RULES - follow every one exactly: "
+            "1. Add keydown/keyup listeners on WINDOW not canvas: window.addEventListener('keydown', e => keys.add(e.key)). "
+            "2. Gravity: every frame do velY += 0.5 AFTER moving, NOT inside collision. "
+            "3. Platform collision: loop ALL platforms, find the one the player is standing on. "
+               "   Set grounded=true and velY=0 ONLY when found. Set grounded=false BEFORE the loop, not inside else. "
+            "4. Jump: if (grounded && (keys.has('ArrowUp') || keys.has('w') || keys.has('W'))) { velY=-12; grounded=false; } "
+            "5. Always add a solid ground platform spanning the full canvas width at y=420. "
+            "6. Use new Image() with src='sprite_NAME.png' for every visual asset, max 3 sprites. "
+            "7. Draw images with ctx.drawImage(img, x, y, w, h). "
             "Output ONLY the raw HTML - no markdown fences, no explanation."
         )
     else:
         system_msg = (
             "You are an expert HTML5 game developer. "
             "Write a complete, working, single-file HTML5 game using only canvas 2D drawing. "
-            "CRITICAL RULES: "
-            "1. Track keyboard input using a Set and keydown/keyup event listeners, NEVER document.key. "
-            "2. Implement real gravity: add 0.5 to velY each frame, reset velY=0 on platform landing. "
-            "3. Implement real jump: only when grounded, set velY=-12. "
-            "4. Never use image files. Draw everything with canvas shapes and colors. "
+            "CRITICAL RULES - follow every one exactly: "
+            "1. Add keydown/keyup listeners on WINDOW not canvas: window.addEventListener('keydown', e => keys.add(e.key)). "
+            "2. Gravity: every frame do velY += 0.5 AFTER moving, NOT inside collision. "
+            "3. Platform collision: loop ALL platforms, find the one the player is standing on. "
+               "   Set grounded=true and velY=0 ONLY when found. Set grounded=false BEFORE the loop, not inside else. "
+            "4. Jump: if (grounded && (keys.has('ArrowUp') || keys.has('w') || keys.has('W'))) { velY=-12; grounded=false; } "
+            "5. Always add a solid ground platform spanning the full canvas width at y=420. "
+            "6. Never use image files. Draw everything with canvas shapes and colors. "
             "Output ONLY the raw HTML - no markdown fences, no explanation."
         )