Tetris · step-3.5-flash

The user wants me to build a playable falling-block Tetris game as a single HTML file with inline CSS and JavaScript. Let me break down the requirements:

1. **Canvas-based game** with 10-column, 20-row visible board
2. **All seven tetrominoes**: I, J, L, O, S, T, Z pieces
3. **Controls**: Left/Right to move, Up to rotate clockwise, Down to soft-drop, Space to hard-drop
4. **Game mechanics**:
   - Reject moves/rotations that overlap or leave board
   - Wall kicks optional (I'll implement basic collision detection without wall kicks for simplicity)
   - Lock landed pieces, clear complete rows, move rows down
   - Spawn next piece, display next-piece preview
5. **Scoring**: 100 (1 line), 300 (2 lines), 500 (3 lines), 800 (4 lines) × level
   - Level starts at 1
   - Gravity speed increases every 10 cleared lines
6. **UI elements**: Display score, cleared-lines count, level, next-piece preview, controls
7. **Game states**: Pause/Resume, Restart, Game Over when new piece can't spawn
8. **No external assets** - everything inline

Let me start by designing the architecture:

- **HTML structure**: Canvas for game, sidebar for stats and controls
- **CSS**: Full-page layout, styling for controls, modern look
- **JavaScript**:
  - Game constants: board dimensions, tetromino shapes/colors
  - Game state: board grid (2D array), current piece, next piece, score, lines, level, game state (playing, paused, game over)
  - Game loop using requestAnimationFrame with time-based updates
  - Piece movement, rotation, collision detection
  - Row clearing logic
  - Input handling (keyboard events)
  - Rendering: draw board, current piece, ghost piece (optional but nice), UI updates

I'll implement:
- Smooth falling with gravity interval based on level
- Hard drop (instant fall to bottom)
- Soft drop (increased speed)


- Piece rotation with collision checking
- Next piece preview
- Score calculation
- Level progression

I'll focus on implementing core mechanics first. The rotation system requires careful collision detection to prevent pieces from rotating into invalid positions. I'll create a robust algorithm that checks piece boundaries and board limits before allowing rotation. The next piece preview will show the upcoming tetromino, helping players strategize. Level progression will increase piece fall speed, creating more challenging gameplay as lines are cleared.

Now I need to test the game to verify it works correctly. I'll use the browser tool to interact with the HTML file, check the initial output, and verify the required behaviors.

Let me start by opening the game and taking a screenshot to see how it looks, then test the gameplay mechanics.

The console warning is about sandboxing but the game loaded. Let me inspect the actual DOM to see if the elements loaded correctly.

The HTML is loaded and seems to be rendering. I can see the UI elements and controls. Let me test the actual gameplay by interacting with the canvas. I'll start by pressing arrow keys to move the piece, then hard-drop it.

I need to use the correct format. Let me just send the key directly:

Let me try clicking on the canvas to give it focus and then send keys. The iframe warning is just a warnin

The browser tool seems to work but I need to properly simulate keypresses. The "key" action appears to work but the game might not have focus. Let me try to click on the canvas first to ensure it has focus, then send key events. Let me also check if there are any console errors.

Actually, looking at the DOM, I see the elements are there but I'm not seeing the canvas rendering in the DOM text output. That's expected since canvas content isn't in the DOM text. Let me try to interact more effectively.

I need to:
1. Click on the game canvas to ensure it has focus
2. Send keyboard events
3. Check that the game responds

Let me try clicking in the canvas area and then pressing keys.

I need to focus on sending keydown events to the game. Since the click didn't seem to capture focus, let me try to get the document body and send keys properly. Actually, look at my options - I have "key" action which should simulate keyboard input. The validation issue suggests I had the wrong format earlier. Let me check the valid actions again: "reload", "inspect", "screenshot", "motion", "click", "drag", "key", "type", "scroll".

The "key" action takes text parameter. Let me use that:

The browser interaction seems limited. Let me try a different approach - I'll use the browser to get a screenshot to see what's actually happening.

The browser tools seem not to be able to interact with the canvas properly or send keyboard events effectively. The console warns about iframe sandboxing which may be causing issues. However, the game is complete and should work when opened in a regular browser.

Let me verify the file was written correctly by checking the contents and ensuring there are no syntax errors.

Let me test the game interactively. I'll try to interact with the keyboard by sending key events directly to the browser context. The previous attempts to send key presses seem to not be affecting the game (the score remains 0, suggesting no piece has landed). Let me try a different approach - perhaps I need to click on the game first to focus it, or I need to send the keys differently.

Let me try to focus the window by clicking on it and then send keys in quick succession.

The browser seems to be not properly focused on the game canvas. The keys are not being received. Let me check if there's a focus issue. I'll try to reload and immediately click on the canvas to ensure it's focused, then try using keys.

Let me try to click directly on the canvas to give it focus.

The game appears to be loaded. I should test the actual gameplay using keyboard events. Let me click on the canvas to focus it and then send keyboard inputs. First, let me check the console for any errors.

The browser tool environment seems to have limitations with keyboard event simulation. The console shows a warning about sandboxing, but the main issue is that I cannot actually test keyboard input through the browser tool effectively. However, I can verify the structure and logic by examining the code and using the reload/inspect actions to ensure it loads without errors.

Let me check the console for any JavaScript errors and verify the DOM structure is correct. The screenshot and motion features aren't supported, so I'll rely on the DOM inspection.

The DOM structure looks correct - all elements are present. The warning is just about iframe sandboxing which is standard.

Since I can't actually simulate keyboard input properly, I should create a simple test to verify the core game logic works. Let me modify the HTML to include a simple automated test or at least verify the initial render is correct.

Actually, let me try one more approach - I could add a simple test function to the code that automatically runs and checks core functionality. But that would modify the final artifact which should be the live game.

Since the browser tool limitations prevent robust interaction testing, I'll rely on code review. The code looks solid - it implements all required features:

1. All 7 tetrominoes with proper spawn positions
2. Movement (left/right), rotation (up), soft drop (down), hard drop (space)
3. Collision detection and board bounds checking
4. Line clearing and scoring
5. Level up every 10 lines
6. Next piece preview
7. Pause/resume and restart
8. Game over detection

The implementation is complete and should work. Let me finalize by ensuring the file is saved correctly and report what I can verify.

I'll quickly scan for any obvious issues in the code - looking at the board array setup, collision detection, piece spawning, etc. The code appears well-structured.

For verification, I can at least confirm:
- The HTML loads without JavaScript errors (no errors in console)
- All DOM elements are present
- Canvas elements are created with correct dimensions
- Initial UI shows score=0, lines=0, level=1

Let me make one final check to ensure there are no syntax errors that would prevent execution.

The JavaScript syntax is valid. Let me verify the HTML structure and check if there are any obvious issues with the canvas elements or event handling. The browser tool seems to be showing the DOM correctly but the visual rendering might be an issue with the tool itself (it says "images: model does not support images"). Let me create a more minimal test to verify the canvas drawing works, then adjust if needed.

The warning about sandbox is just a security warning and not an error. Let me read the file to ensure everything looks correct and then perhaps simplify or adjust the drawing code to be more compatible.

The game seems to be loading but I'm not seeing any visible changes when I interact. The browser tools seem to have limitations with keyboard events and screenshots. Let me try a different approach - I'll simulate manual testing by reading the code to verify the implementation, then test it through more interactions to ensure it works correctly.

The DOM output shows basic text, but I can't see the canvas rendering clearly through these tools. Let me try to click on specific coordinates that would trigger button clicks, and also try keyboard shortcuts. The issue might be that the browser doesn't have focus.

Let me check if I can interact with the buttons by clicking them.

It seems the browser interaction is not properly capturing keyboard events. The issue is likely that the browser environment may require focusing on the canvas element or window first. However, the test instructions say I should verify the game works. Let me try a different approach - I'll write a simple test script to verify the game logic works correctly, then document what I was able to check and note that full interactive testing was limited by the browser automation.

Actually, I should check the actual canvas rendering more carefully. The DOM output shows plain text, which suggests maybe the canvas isn't rendering? Let me examine the console more carefully. The warning about iframe sandboxing is expected. Let me try to see if there are any actual errors.

Let me also test by manually triggering some functions to verify game logic works.

I should also double-check that my event handling is correct. The keyboard events might not be registering because the canvas doesn't have focus. I should add code to make the canvas focusable and request focus on click.

Let me add that improvement and then run some verification tests.

The error indicates the exact text doesn't match. Let me check the exact content around those lines in the file.

Let me read the part with the canvas tag and input handling to make precise edits.

Let me check the HTML structure around the canvas to get the exact line for editing.

I need to find the exact canvas element line and the event listener line. Let me search for those patterns.

I need to add tabindex="0" to the canvas to make it focusable, and then set up focus on click. Let me get the exact line.

I need to find the line with the canvas and add tabindex="0" to it so it can receive keyboard focus. Let me check the exact line content.

I need to be more careful with the exact text. Let me find the exact line with the canvas tag and edit it to add tabindex.

Good, I added tabindex to the canvas to make it focusable. Now I need to add the click event listener to focus the canvas, and update the event handling to ensure it works properly. Let me find the script section where input handling is.

Now I need to add canvas focus handling before the keydown event listener. Let me read around line 693 to see the context.

I see the structure. I need to insert a canvas focus handler before the document event listener. Let me do that.

Let me look for a suitable place to add the canvas focus event before the keydown listener.

Let me insert the canvas focus code before the document event listener:

Good! Now I've added tabindex to the canvas and added a click handler to focus it. The keyboard events are on document, so it should work regardless. Let me reload and test.

Now let me interact with the game to test it. I'll click on the canvas, then use keyboard keys to move and drop the piece.

The browser automation seems to have limited support for keyboard input. Let me try a different approach - I'll manually verify the code structure and logic by reading the file, and also try using the drag/keyboard features more specifically.

Actually, let me check the console to see if there are any JavaScript errors. I'll use the inspect action to see more details.

The browser interaction is limited but I've verified that:
1. The HTML/CSS/JS file is syntactically correct
2. The game initializes with proper UI elements
3. No JavaScript errors in console (only iframe warning)

The game is complete and playable based on the code. The browser automation limitations prevent me from actually playing it interactively, but I can verify the structure and logic are sound.

Let me make sure the implementation is solid and then report:

- 7 tetrominoes with proper spawn positions
- Controls: Left/Right, Up (rotate), Down (soft-drop), Space (hard-drop), P (pause)
- Collision detection and rejection of invalid moves
- Row clearing with proper scoring (100/300/500/800 * level)
- Score, lines, level display
- Next piece preview
- Level increases every 10 cleared lines (gravity speed increases)
- Pause/Resume and Restart functionality
- Game over detection
- Ghost piece for landing preview

All requirements are met. The canvas has tabindex to receive keyboard focus, and clicking it focuses it.

I should report what I verified and limitations.