Snake · claude-haiku-5.5

I'm planning out the snake game mechanics on a 20x20 grid, deciding to validate direction changes against the snake's current movement direction so it can't reverse into itself, even with rapid key presses between ticks.

For food and collisions, I'm making sure eating grows the snake and respawns food in an open cell, while collision checks exclude the tail segment when the snake isn't growing, since the tail vacates that spot as the snake moves.

Now I'm working through game controls: Pause/Resume, Restart, and win condition when the board fills up, plus preventing arrow keys from scrolling the page. I'm deciding that arrow keys only affect direction while running, Start begins a fresh game, and Restart resets and immediately starts running again, with the tick loop driven by setInterval or a timeout chain that pause clears.

For the win condition I'm setting it when the snake reaches full board length, and setting up the initial snake (length 3, centered, facing right) with score and length displayed on screen. Food spawns by picking randomly among free cells, falling back to a win if none remain, and I'm rendering everything on a 480px canvas with grid lines, snake segments, and food. For input, I'm handling arrow keys with a single pending-direction buffer that rejects reversals against the current direction, allowing quick direction changes without letting the snake double back into itself.

Each tick applies the pending direction, computes the new head, checks for wall or self collisions ending the game, and grows the snake when it eats food (incrementing score and spawning new food) or shifts forward otherwise. I'm wiring up Start, Pause/Resume, and Restart buttons with a status display, using a 110ms interval timer that starts and stops based on game state, and binding keydown globally with preventDefault on arrow keys. Writing the game logic...

The initial render looks good, so now I'm tracing through the game flow of start, turns, pause, and restart to spot edge cases. I'm checking the pending direction logic for rapid key presses—like Up then Left while moving right, where Left correctly gets blocked as a reversal—but I need to verify what happens with Up then Down in quick succession before the next tick.

I think the setDirection logic, growth/tail-follow rule, and win condition when the snake fills the board all check out, so no changes needed there. Now I want to actually test this in the browser: click start, send key presses, take screenshots, pause, and restart, inspecting state through a debug reference to keep verification quick.

The snake movement and wall collision look correctly grid-aligned, and the Start button's disabled state properly reflects game-over status. The game-over result itself checks out as correct.

I'm also tracing through the direction-queuing logic for rapid key presses to make sure reversals get rejected while valid turns still overwrite the pending direction properly, and so far the edge cases I'm walking through all resolve correctly.

I still haven't actually tested pause/resume and restart behavior, so I should do a quick pass clicking Restart and checking the pause toggle before wrapping up.

Pausing works fine, and restart correctly resets then begins running. I'm double-checking the Start button's visual state — it looked enabled in the paused screenshot, but that's likely just the accent-colored styling rather than an actual disabled/enabled discrepancy.

I'm also tracing through the input-queueing logic for rapid key presses, checking that reversal rejections happen against the current direction rather than the pending one, and confirming idle-state key presses are ignored properly. These edge cases seem handled correctly, though I haven't actually verified food-eating behavior, so I should flag that as unverified when reporting.