🕹️ Connect 4 AI: Master Edition (v2.0)

A high-performance, feature-rich Connect 4 implementation for the ESP32-C3. This version features a "living" AI that evolves as you play, human-like movement animations, and a robust win-detection engine.

🛠 Hardware Configuration

🔌 Pin Mapping (Lolin C3 Mini)

Component	ESP32-C3 Pin	Function
NeoPixel Matrix	`GPIO 4`	Data Input (DIN)
Rotary Encoder A	`GPIO 0`	Directional CLK
Rotary Encoder B	`GPIO 1`	Directional DT
Encoder Button	`GPIO 2`	Selection (SW)

📐 Physical Layout

The project is optimized for an 8x8 NeoPixel Matrix (65mm x 67mm).

Row 0: Interaction & AI Decision Visualization.
Row 1: Static Blue UI border.
Rows 2-7: Active 7 \times 6 game board.
Status Column: Far right column (Index 7) manages UI framing and "Glow" effects.

🧠 Advanced AI & Logic Features

1. Progressive Difficulty (Evolution Mode)

To keep the game challenging and the CPU efficient, the AI search depth (Ply) scales as the board fills.

Formula: DynamicPly = BasePly + \lfloor \frac{DiscsOnBoard}{7} \rfloor
Benefit: The AI is "casual" in the opening but becomes a "Grandmaster" in the endgame when tactical precision is vital.

2. Intelligent Win Detection & Flashing

The win-engine has been refactored to prevent "color ghosting."

Winner Locking: The scanBoard() function returns the specific ID of the winner (1 for Yellow, 2 for Red).
Flashing Accuracy: The final animation uses this ID to ensure the winning 4-in-a-row flashes in the correct player's color, regardless of whose turn it was when the game ended.

3. Smart Watchdog (Tiered Timeout)

The game respects your "thinking time" by using a tiered idle-timeout system:

Menu/Finished State: Standard timeout (e.g., 60s).
Playing State: Double Timeout (e.g., 120s). This gives human players more time to analyze complex boards before the game auto-resets to Demo Mode.

4. Strategic Blunder Injection

To ensure Demo Mode doesn't end in an infinite loop of draws, a 20% "Blunder Chance" is injected. This forces the AI to occasionally make a human-like mistake, creating openings for a definitive winner.

📖 Code Architecture & Modules

🔄 State Machine

The core loop manages five distinct states:

MENU: Mode selection and board reset.
PLAYING: Active turn-based logic with gravity-accelerated drop animations.
FINISHED_WIN: Locks the winner ID and flashes the winning segment.
FINISHED_DRAW: Blinks the entire board to signify a stalemate.
DEMO: Auto-plays with randomized difficulty (Ply 3-6) and mandatory blunder logic.

🌐 Web Administration Portal

Accessible via the "Connect4-Config" AP at 192.168.4.1.

Base Ply: Sets the starting difficulty level.
Brightness: Global LED intensity (0-255).
Evolution Toggle: Turn on/off the progressive difficulty scaling.
Blunder Toggle: Allow the AI to make mistakes during Human-vs-AI matches.

🛠 Installation

Environment: Use VS Code with the PlatformIO extension.
Dependencies: FastLED, Encoder, Preferences.
Build Flag: Define your WiFi password in platformio.ini: -D WIFI_PASSWORD=\"your_password\".
Flash: Upload to your ESP32-C3 and enjoy the ultimate desktop Connect 4 experience.

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