diff --git a/.planning/ROADMAP.md b/.planning/ROADMAP.md
index 4e86ece..2411265 100644
--- a/.planning/ROADMAP.md
+++ b/.planning/ROADMAP.md
@@ -60,7 +60,11 @@ Plans:
5. Match ends when a player reaches target score with clear game-over state
6. No memory leaks or event listener cleanup issues after multiple rounds
-**Plans**: TBD
+**Plans:** 2 plans
+
+Plans:
+- [ ] 02-01-PLAN.md — Paddle2, AI system (predictive interception + 3 difficulty levels), extended Input/Physics
+- [ ] 02-02-PLAN.md — Game state machine, scoring, match-end, re-serve, paddle2 rendering, mode/difficulty selection
---
@@ -138,7 +142,7 @@ Plans:
| Phase | Plans Complete | Status | Completed |
|-------|----------------|--------|-----------|
| 1. Foundation | 1/2 | In Progress | — |
-| 2. Core Gameplay | 0/? | Not started | — |
+| 2. Core Gameplay | 0/2 | Not started | — |
| 3. Complete Experience | 0/? | Not started | — |
| 4. Polish & Depth | 0/? | Not started | — |
| 5. Release | 0/? | Not started | — |
@@ -147,3 +151,4 @@ Plans:
*Roadmap created: 2026-03-10*
*Phase 1 planned: 2026-03-10*
+*Phase 2 planned: 2026-03-10*
diff --git a/.planning/phases/02-core-gameplay/02-01-PLAN.md b/.planning/phases/02-core-gameplay/02-01-PLAN.md
new file mode 100644
index 0000000..5c02837
--- /dev/null
+++ b/.planning/phases/02-core-gameplay/02-01-PLAN.md
@@ -0,0 +1,367 @@
+---
+phase: 02-core-gameplay
+plan: 01
+type: execute
+wave: 1
+depends_on: []
+files_modified: [index.html]
+autonomous: true
+requirements: [CORE-08, AI-01, AI-02, AI-03, AI-04]
+must_haves:
+ truths:
+ - "Player 2 can move their paddle up and down with ArrowUp/ArrowDown keys"
+ - "AI paddle tracks and intercepts the ball using predictive ray-cast logic"
+ - "Easy AI is visibly slow with a large reaction delay — beatable by any player"
+ - "Medium AI reacts at moderate speed — provides a fair challenge"
+ - "Hard AI reacts fast but not perfectly — still beatable with skill"
+ - "Ball deflects off paddle2 the same way it deflects off paddle1 (zone-based angle)"
+ artifacts:
+ - path: "index.html"
+ provides: "GameState.paddle2 object, AI module, extended Input, extended Physics"
+ contains: "AI_EASY, AI_MEDIUM, AI_HARD, getVerticalInput2, _checkPaddle2Collision"
+ key_links:
+ - from: "Physics.update()"
+ to: "AI.update(deltaTime)"
+ via: "called when GameState.mode === 'ai'"
+ pattern: "AI\\.update"
+ - from: "Physics.update()"
+ to: "_checkPaddle2Collision"
+ via: "called when ball.vx > 0"
+ pattern: "ball\\.vx > 0"
+ - from: "AI._predictBallY()"
+ to: "wall bounce simulation"
+ via: "stepped ray cast loop"
+ pattern: "while.*steps < maxSteps"
+---
+
+
+Add paddle2 (Player 2 or AI-controlled) and the full AI opponent system to index.html.
+
+Purpose: Make the game two-sided — ball now has a right paddle to deflect off. Player 2 can be human (Up/Down arrows) or AI (predictive interception with 3 tunable difficulty levels).
+Output: index.html with GameState.paddle2, extended Input (ArrowUp/ArrowDown + named handler refs for cleanup), AI object with predictive ray-cast interception, extended Physics.update() with paddle2 movement branch and paddle2 collision detection.
+
+
+
+@/home/dabit/.claude/get-shit-done/workflows/execute-plan.md
+@/home/dabit/.claude/get-shit-done/templates/summary.md
+
+
+
+@.planning/PROJECT.md
+@.planning/ROADMAP.md
+@.planning/STATE.md
+@.planning/phases/02-core-gameplay/02-CONTEXT.md
+@.planning/phases/02-core-gameplay/02-RESEARCH.md
+
+
+
+
+GameConfig (existing — extend, do NOT replace):
+```javascript
+const GameConfig = {
+ initialBallSpeed: 220,
+ speedIncrement: 18,
+ paddleSpeed: 400
+ // Plan 02-01 adds: WIN_SCORE, AI_EASY, AI_MEDIUM, AI_HARD
+};
+```
+
+GameState.paddle1 (existing structure — paddle2 MUST mirror this):
+```javascript
+paddle1: {
+ x: 30, y: ,
+ width: 12, height: 80,
+ speed: 400,
+ color: '#fff'
+}
+```
+
+GameState.ball (existing):
+```javascript
+ball: { x, y, radius: 8, vx, vy, speed, color: '#fff' }
+```
+
+Input (existing — extend, do NOT replace):
+```javascript
+const Input = {
+ keys: { w: false, s: false },
+ init() { /* anonymous addEventListener keydown/keyup */ },
+ getVerticalInput() { /* returns -1/0/1 for W/S */ }
+};
+```
+
+Physics._checkPaddleCollision(ball, paddle) (existing — reuse for paddle2):
+- AABB collision + zone-based deflection
+- Sets ball.vx positive (away from paddle1, left side)
+- Needs a mirrored version for paddle2 that sets ball.vx negative and pushes ball LEFT
+
+Physics.update(deltaTime) (existing — extend):
+```javascript
+update(deltaTime) {
+ // Moves paddle1 (Input.getVerticalInput)
+ // Moves ball (vx*dt, vy*dt)
+ // Wall bounces (top/bottom)
+ // Out-of-bounds reset (left or right) → this.serveBall()
+ // Paddle1 collision (only when ball.vx < 0)
+}
+```
+
+GameLoop.main(currentTime) (existing — NOT modified in this plan):
+```javascript
+main(currentTime) {
+ const deltaTime = Math.min((currentTime - this.lastTime) / 1000, 0.05);
+ Physics.update(deltaTime);
+ Renderer.clear();
+ // draws debug speed, paddle1, ball
+}
+```
+
+
+
+
+
+
+ Task 1: Extend GameConfig, GameState, and Input for two-player support
+ index.html
+
+Make these additions to index.html inside the existing `<script>` tag. Do NOT rewrite the whole file — surgical additions only.
+
+**1. Extend GameConfig** (add after `paddleSpeed: 400`):
+```javascript
+WIN_SCORE: 7,
+
+AI_EASY: { speed: 200, reactionDelay: 0.3, errorMargin: 20 },
+AI_MEDIUM: { speed: 320, reactionDelay: 0.1, errorMargin: 5 },
+AI_HARD: { speed: 400, reactionDelay: 0.05, errorMargin: 2 }
+```
+
+**2. Extend GameState** (add after `ball: {...}`, inside the GameState object):
+```javascript
+paddle2: {
+ x: 0, y: 0, // Set on Physics.init()
+ width: 12, height: 80,
+ speed: 400,
+ color: '#fff'
+},
+score1: 0,
+score2: 0,
+mode: null, // null = mode select screen; 'ai' = Solo vs AI; '2p' = 2-Player local
+difficulty: 'medium', // 'easy', 'medium', 'hard'
+gameState: 'modeSelect',// 'modeSelect', 'diffSelect', 'playing', 'scored', 'gameover'
+winner: null // null, 'player1', 'player2', 'ai'
+```
+
+**3. Refactor Input** to use named handler refs for cleanup (replace the existing Input object entirely — the existing one has anonymous handlers that can't be removed):
+```javascript
+const Input = {
+ keys: { w: false, s: false, arrowUp: false, arrowDown: false },
+ _handleKeyDown: null,
+ _handleKeyUp: null,
+
+ init() {
+ this._handleKeyDown = (e) => {
+ if (e.code === 'KeyW') { this.keys.w = true; e.preventDefault(); }
+ if (e.code === 'KeyS') { this.keys.s = true; e.preventDefault(); }
+ if (e.code === 'ArrowUp') { this.keys.arrowUp = true; e.preventDefault(); }
+ if (e.code === 'ArrowDown') { this.keys.arrowDown = true; e.preventDefault(); }
+ };
+ this._handleKeyUp = (e) => {
+ if (e.code === 'KeyW') this.keys.w = false;
+ if (e.code === 'KeyS') this.keys.s = false;
+ if (e.code === 'ArrowUp') this.keys.arrowUp = false;
+ if (e.code === 'ArrowDown') this.keys.arrowDown = false;
+ };
+ document.addEventListener('keydown', this._handleKeyDown);
+ document.addEventListener('keyup', this._handleKeyUp);
+ },
+
+ cleanup() {
+ document.removeEventListener('keydown', this._handleKeyDown);
+ document.removeEventListener('keyup', this._handleKeyUp);
+ },
+
+ getVerticalInput() { return this.keys.w ? -1 : this.keys.s ? 1 : 0; },
+ getVerticalInput2() { return this.keys.arrowUp ? -1 : this.keys.arrowDown ? 1 : 0; }
+};
+```
+
+**4. Extend Physics.init()** — add paddle2 positioning after the existing paddle1 positioning:
+```javascript
+// Position paddle2 on right side, vertically centered
+GameState.paddle2.x = width - 30 - GameState.paddle2.width;
+GameState.paddle2.y = height / 2 - GameState.paddle2.height / 2;
+GameState.paddle2.speed = GameConfig.paddleSpeed;
+```
+
+Also extend `Physics.onResize()` to call `this.init(width, height)` so paddle2 is repositioned on resize (the existing `onResize` only updates `this.width/height`).
+
+
+Open index.html in browser. Open DevTools console — no errors on load.
+Verify in console: `GameState.paddle2` has x, y, width, height, speed, color. `GameConfig.AI_EASY` exists. `Input.getVerticalInput2` is a function.
+
+ GameState has paddle2 mirroring paddle1 structure. GameConfig has WIN_SCORE and all three AI difficulty presets. Input has named handler refs, cleanup(), getVerticalInput2(). No console errors.
+
+
+
+ Task 2: Add AI module and extend Physics for paddle2 movement and collision
+ index.html
+
+Add the AI object between Physics and GameLoop. Then extend Physics.update() to handle paddle2.
+
+**1. Add AI object** (insert between the closing `};` of Physics and the opening `const GameLoop = {`):
+```javascript
+const AI = {
+ reactionElapsed: 0,
+
+ init() {
+ this.reactionElapsed = 0;
+ },
+
+ update(deltaTime) {
+ const difficulty = GameState.difficulty;
+ const config = GameConfig['AI_' + difficulty.toUpperCase()];
+ const ball = GameState.ball;
+ const paddle2 = GameState.paddle2;
+
+ // Reset reaction timer when ball is moving away (toward player side)
+ if (ball.vx < 0) {
+ this.reactionElapsed = 0;
+ return; // Ball heading toward player — AI waits
+ }
+
+ this.reactionElapsed += deltaTime;
+ if (this.reactionElapsed < config.reactionDelay) {
+ return; // Still in reaction delay window
+ }
+
+ // Predict ball y-position when it reaches paddle2 x
+ const targetY = this._predictBallY(ball, paddle2.x);
+
+ // Add difficulty-based error margin (random jitter each frame)
+ const error = (Math.random() - 0.5) * config.errorMargin * 2;
+ const aimY = targetY + error;
+
+ // Move paddle toward aim Y (clamped to field)
+ const centerY = paddle2.y + paddle2.height / 2;
+ const diff = aimY - centerY;
+
+ if (Math.abs(diff) > 3) { // Deadzone prevents jitter
+ const dir = Math.sign(diff);
+ paddle2.y += dir * config.speed * deltaTime;
+ paddle2.y = Math.max(0, Math.min(Physics.height - paddle2.height, paddle2.y));
+ }
+ },
+
+ _predictBallY(ball, targetX) {
+ let x = ball.x, y = ball.y, vx = ball.vx, vy = ball.vy;
+ const maxSteps = 500;
+ let steps = 0;
+
+ while (steps < maxSteps) {
+ if (Math.abs(x - targetX) < 1) break;
+ const timeToTarget = (targetX - x) / vx;
+ const timeStep = Math.min(0.016, Math.abs(timeToTarget));
+
+ x += vx * timeStep;
+ y += vy * timeStep;
+
+ // Wall bounces during prediction
+ if (y - ball.radius < 0) {
+ y = ball.radius;
+ vy = Math.abs(vy);
+ } else if (y + ball.radius > Physics.height) {
+ y = Physics.height - ball.radius;
+ vy = -Math.abs(vy);
+ }
+ steps++;
+ }
+
+ return y;
+ }
+};
+```
+
+**2. Add `_checkPaddle2Collision(ball, paddle)` to Physics** (add after `_checkPaddleCollision`):
+```javascript
+_checkPaddle2Collision(ball, paddle) {
+ const inX = ball.x + ball.radius > paddle.x &&
+ ball.x - ball.radius < paddle.x + paddle.width;
+ const inY = ball.y + ball.radius > paddle.y &&
+ ball.y - ball.radius < paddle.y + paddle.height;
+
+ if (!inX || !inY) return;
+
+ const relativeHitPos = (ball.y - paddle.y) / paddle.height;
+ const hitZone = Math.max(0, Math.min(4, Math.floor(relativeHitPos * 5)));
+ const anglesDeg = [-60, -30, 5, 30, 60];
+ const angleRad = anglesDeg[hitZone] * Math.PI / 180;
+
+ ball.speed += GameConfig.speedIncrement;
+
+ // Ball leaves paddle2 going LEFT (negative vx)
+ ball.vx = -Math.cos(angleRad) * ball.speed;
+ ball.vy = Math.sin(angleRad) * ball.speed;
+
+ // Push ball left of paddle2 to prevent double-collision
+ ball.x = paddle.x - ball.radius - 1;
+},
+```
+
+**3. Extend Physics.update()** — after the existing paddle1 movement block, add paddle2 movement (replace the existing out-of-bounds reset with scoring-aware version in Plan 02-02; for now keep the existing reset but ADD paddle2 movement and collision):
+
+Add after `paddle.y = Math.max(0, Math.min(...));` (end of paddle1 movement):
+```javascript
+// --- Move paddle2 (human or AI) ---
+const paddle2 = GameState.paddle2;
+if (GameState.mode === '2p') {
+ const dir2 = Input.getVerticalInput2();
+ paddle2.y += dir2 * paddle2.speed * deltaTime;
+ paddle2.y = Math.max(0, Math.min(this.height - paddle2.height, paddle2.y));
+} else if (GameState.mode === 'ai') {
+ AI.update(deltaTime);
+}
+```
+
+Add after the existing `if (ball.vx < 0) this._checkPaddleCollision(ball, paddle);`:
+```javascript
+// --- Paddle2 collision (only when ball moving right toward paddle2) ---
+if (ball.vx > 0) {
+ this._checkPaddle2Collision(ball, GameState.paddle2);
+}
+```
+
+**4. Add `AI.init()` to the initialization block** at the bottom of the script (after `Input.init()`):
+```javascript
+AI.init();
+```
+
+
+Open index.html. Ball should still bounce and Player 1 W/S still works. Open console — no errors. Verify `typeof AI.update === 'function'` and `typeof Physics._checkPaddle2Collision === 'function'`. Paddle2 is not yet visible (rendering added in Plan 02-02) but it exists in GameState with valid coordinates.
+
+ AI object exists with init(), update(), _predictBallY(). Physics has _checkPaddle2Collision(). Physics.update() includes paddle2 movement branch (2p/ai). No console errors. Paddle1 W/S still works.
+
+
+
+
+
+After both tasks:
+- `GameState.paddle2` has x, y, width, height, speed, color (mirrors paddle1 structure)
+- `Input.cleanup()` is callable (named handlers stored on Input object)
+- `Input.getVerticalInput2()` returns -1/0/1 for ArrowUp/ArrowDown
+- `AI.update(deltaTime)` moves paddle2 toward predicted ball intercept when mode === 'ai'
+- `AI._predictBallY()` simulates wall bounces in its ray cast loop (not linear interpolation)
+- `Physics._checkPaddle2Collision()` uses same 5-zone deflection as paddle1 but sends ball LEFT
+- Ball still bounces off walls and Player 1 can still hit it (existing behavior unchanged)
+
+
+
+- ArrowUp moves paddle2 up; ArrowDown moves paddle2 down (requires mode selection in Plan 02-02 to fully test, but can test by temporarily setting `GameState.mode = '2p'` in console)
+- In AI mode, paddle2 moves toward ball intercept position
+- Ball deflects off paddle2 (check by setting mode in console and playing)
+- `typeof AI._predictBallY === 'function'` is true
+- No console errors on load or during play
+
+
+
diff --git a/.planning/phases/02-core-gameplay/02-02-PLAN.md b/.planning/phases/02-core-gameplay/02-02-PLAN.md
new file mode 100644
index 0000000..34d3656
--- /dev/null
+++ b/.planning/phases/02-core-gameplay/02-02-PLAN.md
@@ -0,0 +1,376 @@
+---
+phase: 02-core-gameplay
+plan: 02
+type: execute
+wave: 2
+depends_on: [02-01]
+files_modified: [index.html]
+autonomous: false
+requirements: [CORE-05, CORE-06]
+must_haves:
+ truths:
+ - "Player scores a point when ball exits past opponent's paddle edge"
+ - "Scores display on canvas in real time, visible to both players"
+ - "Ball pauses ~1 second after a score, then auto-serves"
+ - "Match ends when a player reaches 7 points with a winner message on screen"
+ - "R key restarts the match (scores reset, mode/difficulty selection reappears)"
+ - "Mode is selected by pressing 1 (Solo vs AI) or 2 (2-Player)"
+ - "Difficulty is selected by pressing 1/2/3 (Easy/Medium/Hard) before match starts"
+ - "Both paddles render on screen during gameplay"
+ artifacts:
+ - path: "index.html"
+ provides: "GameLoop with scoring detection, state machine, rendering of paddle2 and scores"
+ contains: "gameState.*modeSelect, score1, score2, gameover, WIN_SCORE"
+ key_links:
+ - from: "GameLoop.main()"
+ to: "score detection"
+ via: "checks ball.x after Physics.update()"
+ pattern: "score[12]\\+\\+"
+ - from: "GameLoop.main()"
+ to: "match-end check"
+ via: "score >= WIN_SCORE condition"
+ pattern: "WIN_SCORE"
+ - from: "GameLoop.main()"
+ to: "re-serve after pause"
+ via: "scored state + elapsed > 1.0"
+ pattern: "elapsed > 1"
+---
+
+
+Wire game state machine, scoring detection, match-end condition, re-serve timing, rendering of paddle2 and score display, and mode/difficulty selection flow into index.html.
+
+Purpose: Transform the two-paddle foundation (from Plan 02-01) into a fully playable game with score tracking, match progression, and a clear start/restart flow.
+Output: Complete Phase 2 — a playable single-player (vs AI) or 2-player local Pong match that ends at 7 points with mode/difficulty selection and R-key restart.
+
+
+
+@/home/dabit/.claude/get-shit-done/workflows/execute-plan.md
+@/home/dabit/.claude/get-shit-done/templates/summary.md
+
+
+
+@.planning/PROJECT.md
+@.planning/ROADMAP.md
+@.planning/phases/02-core-gameplay/02-CONTEXT.md
+@.planning/phases/02-core-gameplay/02-RESEARCH.md
+@.planning/phases/02-core-gameplay/02-01-SUMMARY.md
+
+
+
+
+GameState fields added in Plan 02-01:
+```javascript
+GameState.score1 // 0
+GameState.score2 // 0
+GameState.mode // null | 'ai' | '2p'
+GameState.difficulty // 'easy' | 'medium' | 'hard'
+GameState.gameState // 'modeSelect' | 'diffSelect' | 'playing' | 'scored' | 'gameover'
+GameState.winner // null | 'player1' | 'player2' | 'ai'
+GameState.paddle2 // { x, y, width, height, speed, color }
+```
+
+GameConfig fields added in Plan 02-01:
+```javascript
+GameConfig.WIN_SCORE // 7
+GameConfig.AI_EASY/MEDIUM/HARD // { speed, reactionDelay, errorMargin }
+```
+
+Physics.serveBall() (existing) — resets ball to center with random direction; does NOT reset scores.
+
+Physics.init(width, height) — positions both paddles and calls serveBall(); can be used for full restart.
+
+
+
+
+
+
+ Task 1: State machine — mode/difficulty selection, scoring, match end, and restart
+ index.html
+
+Rewrite `GameLoop.main()` to implement the full game state machine. Also add key handlers for mode/difficulty selection and R-key restart to Input (append to the existing `_handleKeyDown` handler — do NOT replace the arrow/WASD key handling already there).
+
+**1. Add mode/difficulty/restart key handling** inside Input._handleKeyDown (add AFTER the ArrowDown block):
+```javascript
+// Mode selection (only when in modeSelect state)
+if (e.code === 'Digit1' && GameState.gameState === 'modeSelect') {
+ GameState.mode = 'ai';
+ GameState.gameState = 'diffSelect';
+}
+if (e.code === 'Digit2' && GameState.gameState === 'modeSelect') {
+ GameState.mode = '2p';
+ // Skip difficulty selection for 2-player — go straight to playing
+ GameState.gameState = 'playing';
+ Physics.serveBall();
+}
+
+// Difficulty selection (only when in diffSelect state)
+if (e.code === 'Digit1' && GameState.gameState === 'diffSelect') {
+ GameState.difficulty = 'easy';
+ AI.init();
+ GameState.gameState = 'playing';
+ Physics.serveBall();
+}
+if (e.code === 'Digit2' && GameState.gameState === 'diffSelect') {
+ GameState.difficulty = 'medium';
+ AI.init();
+ GameState.gameState = 'playing';
+ Physics.serveBall();
+}
+if (e.code === 'Digit3' && GameState.gameState === 'diffSelect') {
+ GameState.difficulty = 'hard';
+ AI.init();
+ GameState.gameState = 'playing';
+ Physics.serveBall();
+}
+
+// Restart (only when gameover)
+if (e.code === 'KeyR' && GameState.gameState === 'gameover') {
+ GameState.score1 = 0;
+ GameState.score2 = 0;
+ GameState.winner = null;
+ GameState.mode = null;
+ GameState.difficulty = 'medium';
+ GameState.gameState = 'modeSelect';
+ AI.init();
+ Physics.init(Renderer.logicalWidth, Renderer.logicalHeight);
+}
+```
+
+**2. Rewrite GameLoop.main()** (replace the entire existing `main(currentTime)` method):
+```javascript
+main(currentTime) {
+ this.stopHandle = window.requestAnimationFrame(this.main.bind(this));
+ const deltaTime = Math.min((currentTime - this.lastTime) / 1000, 0.05);
+ this.lastTime = currentTime;
+
+ const gs = GameState;
+ const ball = gs.ball;
+
+ // --- Physics update (only during active play) ---
+ if (gs.gameState === 'playing') {
+ Physics.update(deltaTime);
+
+ // Score detection — AFTER Physics.update(), NOT inside Physics
+ if (ball.x + ball.radius < 0) {
+ // Ball exited left edge → Player 2 (or AI) scores
+ gs.score2++;
+ gs.gameState = 'scored';
+ this.pauseTime = currentTime;
+ } else if (ball.x - ball.radius > Physics.width) {
+ // Ball exited right edge → Player 1 scores
+ gs.score1++;
+ gs.gameState = 'scored';
+ this.pauseTime = currentTime;
+ }
+
+ // Match-end check immediately after scoring
+ if (gs.score1 >= GameConfig.WIN_SCORE) {
+ gs.gameState = 'gameover';
+ gs.winner = 'player1';
+ } else if (gs.score2 >= GameConfig.WIN_SCORE) {
+ gs.gameState = 'gameover';
+ gs.winner = gs.mode === 'ai' ? 'ai' : 'player2';
+ }
+ }
+
+ // --- Auto-serve after ~1s pause ---
+ if (gs.gameState === 'scored') {
+ const elapsed = (currentTime - this.pauseTime) / 1000;
+ if (elapsed >= 1.0) {
+ Physics.serveBall();
+ gs.gameState = 'playing';
+ }
+ }
+
+ // --- Render ---
+ Renderer.clear();
+
+ if (gs.gameState === 'modeSelect') {
+ // Mode selection prompt
+ Renderer.ctx.fillStyle = '#fff';
+ Renderer.ctx.font = 'bold 28px monospace';
+ Renderer.ctx.textAlign = 'center';
+ Renderer.ctx.fillText('SUPER PONG NEXT GEN', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 - 60);
+ Renderer.ctx.font = '20px monospace';
+ Renderer.ctx.fillText('Press 1 — Solo vs AI', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2);
+ Renderer.ctx.fillText('Press 2 — 2 Player Local', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 + 36);
+ Renderer.ctx.textAlign = 'left';
+ return;
+ }
+
+ if (gs.gameState === 'diffSelect') {
+ Renderer.ctx.fillStyle = '#fff';
+ Renderer.ctx.font = 'bold 24px monospace';
+ Renderer.ctx.textAlign = 'center';
+ Renderer.ctx.fillText('SELECT DIFFICULTY', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 - 50);
+ Renderer.ctx.font = '20px monospace';
+ Renderer.ctx.fillText('1 — Easy', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2);
+ Renderer.ctx.fillText('2 — Medium', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 + 36);
+ Renderer.ctx.fillText('3 — Hard', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 + 72);
+ Renderer.ctx.textAlign = 'left';
+ return;
+ }
+
+ // --- Gameplay rendering (playing, scored, gameover) ---
+
+ // Paddles
+ const p1 = gs.paddle1;
+ const p2 = gs.paddle2;
+ Renderer.drawRect(p1.x, p1.y, p1.width, p1.height, p1.color);
+ Renderer.drawRect(p2.x, p2.y, p2.width, p2.height, p2.color);
+
+ // Ball (stationary during scored pause)
+ if (gs.gameState !== 'scored') {
+ const b = gs.ball;
+ Renderer.drawCircle(b.x, b.y, b.radius, b.color);
+ }
+
+ // Center divider line (dashed)
+ Renderer.ctx.setLineDash([10, 14]);
+ Renderer.ctx.strokeStyle = 'rgba(255,255,255,0.2)';
+ Renderer.ctx.lineWidth = 2;
+ Renderer.ctx.beginPath();
+ Renderer.ctx.moveTo(Renderer.logicalWidth / 2, 0);
+ Renderer.ctx.lineTo(Renderer.logicalWidth / 2, Renderer.logicalHeight);
+ Renderer.ctx.stroke();
+ Renderer.ctx.setLineDash([]);
+
+ // Scores
+ Renderer.ctx.fillStyle = 'rgba(255,255,255,0.8)';
+ Renderer.ctx.font = 'bold 48px monospace';
+ Renderer.ctx.textAlign = 'center';
+ Renderer.ctx.fillText(gs.score1, Renderer.logicalWidth / 4, 64);
+ Renderer.ctx.fillText(gs.score2, Renderer.logicalWidth * 3 / 4, 64);
+ Renderer.ctx.textAlign = 'left';
+
+ // Game over overlay
+ if (gs.gameState === 'gameover') {
+ const winnerName = gs.winner === 'player1' ? 'Player 1' :
+ gs.winner === 'ai' ? 'AI' : 'Player 2';
+ Renderer.ctx.fillStyle = 'rgba(0,0,0,0.5)';
+ Renderer.ctx.fillRect(0, 0, Renderer.logicalWidth, Renderer.logicalHeight);
+ Renderer.ctx.fillStyle = '#fff';
+ Renderer.ctx.font = 'bold 36px monospace';
+ Renderer.ctx.textAlign = 'center';
+ Renderer.ctx.fillText(winnerName + ' Wins!', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 - 20);
+ Renderer.ctx.font = '20px monospace';
+ Renderer.ctx.fillText('Press R to play again', Renderer.logicalWidth / 2, Renderer.logicalHeight / 2 + 24);
+ Renderer.ctx.textAlign = 'left';
+ }
+},
+```
+
+**3. Add `pauseTime` field to GameLoop object** (add alongside `stopHandle: null, lastTime: 0`):
+```javascript
+pauseTime: 0,
+```
+
+**4. Remove the Phase 1 debug speed display** — delete this block from wherever it appears in the old main():
+```javascript
+// Debug: show ball speed (keep for Phase 1 verification)
+Renderer.ctx.fillStyle = 'rgba(255,255,255,0.4)';
+Renderer.ctx.font = '14px monospace';
+Renderer.ctx.fillText('speed: ' + Math.round(GameState.ball.speed), 10, 20);
+```
+
+**5. Remove the Phase 1 automatic re-serve** from Physics.update() — the old code called `this.serveBall()` when ball went out of bounds. Replace that entire out-of-bounds block with NOTHING (Plan 02-02's GameLoop now owns scoring and serve). Remove:
+```javascript
+// --- Ball out of bounds (left or right) → reset ---
+if (ball.x + ball.radius < 0 || ball.x - ball.radius > this.width) {
+ this.serveBall();
+ return;
+}
+```
+Physics.update() should no longer call serveBall() or detect out-of-bounds. Scoring detection is GameLoop's responsibility.
+
+**Critical:** Do not skip this step — if Physics still auto-resets the ball, scores will never increment.
+
+
+Open index.html in browser.
+1. Verify mode select screen appears on load (title + "Press 1 — Solo vs AI / Press 2 — 2 Player Local")
+2. Press 2 → 2-Player mode starts immediately; both paddles visible; W/S moves left paddle, Up/Down moves right paddle
+3. Play until ball exits right edge → score on left side increments; ~1s pause; ball re-serves
+4. Play until ball exits left edge → score on right side increments
+5. Play to 7 points → winner overlay appears with "Player X Wins!" and "Press R to play again"
+6. Press R → returns to mode select screen with scores reset
+7. Press 1 → difficulty select screen appears; Press 2 → Medium difficulty; AI paddle tracks ball
+8. Verify no console errors throughout
+
+
+- Mode select screen shows on load
+- 2-Player: both paddles controllable, scoring works, match ends at 7
+- Solo vs AI: difficulty selection works, AI tracks ball, match ends at 7
+- R key resets to mode select with clean state
+- No Phase 1 debug speed text on screen
+- No console errors
+
+
+
+
+ Checkpoint: Verify Phase 2 complete gameplay
+ index.html
+ Human verification of completed Phase 2 gameplay. No code changes — user plays the game and confirms all behaviors match the checklist in how-to-verify.
+ All items in how-to-verify checklist confirmed by user.
+ User types "approved" — all Phase 2 success criteria verified through manual play.
+
+Complete Phase 2: paddle2 (human or AI), scoring system, match-end condition, re-serve timing, mode/difficulty selection, and winner display — all in index.html.
+
+
+Run through this checklist:
+
+**Player 2 Input (2-Player mode):**
+1. Load index.html. Press 2 (2-Player mode).
+2. Press ArrowUp — right paddle moves up smoothly, no lag.
+3. Press ArrowDown — right paddle moves down.
+4. Press both simultaneously — paddle stops.
+5. Release — paddle stops immediately.
+
+**Scoring:**
+6. Let ball exit left edge — right score (top-right number) increments.
+7. Let ball exit right edge — left score (top-left number) increments.
+8. Ball pauses ~1 second, then auto-serves.
+
+**Match End:**
+9. Play until 7-0 — winner overlay appears: "Player X Wins!" with "Press R to play again".
+10. Press R — mode select screen returns, scores show 0.
+
+**AI Mode:**
+11. Press 1 (Solo vs AI) — difficulty select shows (Easy/Medium/Hard).
+12. Press 1 — Easy. Watch AI paddle for 2 minutes — Easy AI should miss regularly.
+13. Press R, press 1, press 3 (Hard). Verify Hard AI is noticeably faster and more accurate than Easy.
+14. Verify AI still intercepts balls that bounce off top/bottom walls.
+
+**Memory and Stability:**
+15. Play 3 complete matches. Open DevTools Console — no errors or warnings.
+16. Scores reset correctly on each restart.
+
+ Type "approved" if all checks pass, or describe any issues found.
+
+
+
+
+
+Phase 2 complete when all of the following are true:
+1. Mode select screen displays on load (no mid-game start)
+2. 2-Player: W/S controls paddle1, ArrowUp/ArrowDown controls paddle2
+3. AI mode: paddle2 moves autonomously toward ball intercept position
+4. Ball exits left edge → score2 increments; exits right edge → score1 increments
+5. 1-second pause after each score, then auto-serve
+6. First to 7 points triggers gameover state with winner message
+7. R key restarts cleanly (scores reset, mode = null, gameState = modeSelect)
+8. No console errors after 10+ rounds
+
+
+
+All 6 Phase 2 success criteria from ROADMAP.md are met:
+1. Player 2 can control paddle with Up/Down arrow keys independently from Player 1 (CORE-08)
+2. AI opponent successfully tracks and intercepts the ball with behavior varying by difficulty (AI-01)
+3. Easy AI is beatable by average players; Medium provides fair challenge; Hard requires skill (AI-02, AI-03, AI-04)
+4. Player scores point when ball passes opponent's paddle (CORE-05)
+5. Match ends when a player reaches 7 points with clear game-over state (CORE-06)
+6. No memory leaks or event listener cleanup issues after multiple rounds (Input.cleanup() implemented)
+
+
+