Maze generator & solver · claude-haiku-5.5

I'm planning the maze structure as a grid of cells with wall booleans, then setting up recursive backtracking generation animated step-by-step using a stack and generation token to allow restarts.

For solving, I'll support BFS/A* with animated frontier exploration and visited marking, then reconstruct and highlight the path via parent pointers once the target is found, with a replay function to rerun the chosen algorithm. Drawing involves rendering grid walls as lines, coloring explored cells, and drawing the final path as a polyline through cell centers with start/end markers in distinct colors.

Setting up canvas and grid dimensions...

I'm structuring the maze cells with wall data and designing a token-based animation loop using requestAnimationFrame, where each frame runs a step function and redraws until completion, then triggers a callback.

For the generation and solving logic, I'm defining job objects with step functions: the generator carves cells via a DFS stack with a configurable steps-per-frame rate, and the solver resets each cell's exploration state before running pathfinding from start to goal.

For BFS and A* I'm unifying both into a shared frontier structure—BFS shifts the queue front, A* pops the lowest f-score (g+h) node—marking cells explored, tracking parents, and updating neighbors until the goal is found. Once found, I trace back through parent pointers to build the path, then reveal it progressively frame-by-frame as a growing polyline.

Now I'm designing the drawing logic: coloring cells by state (explored in light blue, start green, finish red, current carving/search cell orange), rendering maze walls as line segments based on each cell's wall flags, drawing the gold path polyline up to the current progress, and adding start/finish text labels plus a legend of colored swatches explaining each state.

I'm planning the UI controls (New Maze, Replay Solver, algorithm selector) and the animation loop structure, using an incrementing token so starting a new job cancels any in-flight generation or solving frames. I need to make sure each cell's visited/explored flags reset properly between a fresh maze and a replayed solve, and I'm tuning how many steps run per animation frame for generation versus solving versus path drawing to keep the pacing smooth.

The screenshot looks fine for carving progress. I'm noticing gridlines appear on every cell since all walls start true and get drawn by default—each cell shows N/W borders, with S/E only on the outer boundary, meaning interior walls are essentially double-drawn.

Thinking through consistency: shared walls between adjacent cells get represented once (N of lower cell covers S of the one above), and carving properly removes walls on both sides, so that logic checks out. I'm also verifying the A* solver tracks explored nodes and updates g-scores correctly, and that the draw phase skips explored markers during generation.

One thing I want to double-check is the animation token handling—clicking "New Maze" mid-solve should properly cancel the old render loop via the incrementing token, and the handoff from generation finishing into starting the solver's new frame loop needs to not create overlapping loops.

I also want to verify the path-reveal phase: once the solver finds the goal, it should swap the job function to a path-stepping routine and the frame loop should pick that up seamlessly on the next tick. Given limited time, I'll just click "New Maze" mid-animation and take a screenshot to visually confirm no glitches occur.

The New Maze click worked, confirmed by a fresh carving with a different layout and no leftovers. Now I want to check the solver and final state, but since there's no wait action available, I'll just take another screenshot after a moment to see the progress.

The solved maze image looks correct — the path draws through cell centers under the walls, crossing only open passages, and the border looks fine. Let me check for anything else that might need fixing.

The A* heuristic seems fine, and explored cells are properly filled during solving. I haven't programmatically verified replay, algorithm switching, BFS, or mid-solve cancellation, but since the path is built via parent links that only traverse passable edges, the logic should be sound — given limited time, I'll wrap up with what's verified.