♟️ C Chess Engine (Console)

A complete Chess game developed in C, featuring an Artificial Intelligence based on the Minimax algorithm with Alpha-Beta Pruning and heuristic board evaluation.

The project was made using Single Responsibility principles.

🧠 Artificial Intelligence

The computer makes decisions by calculating thousands of moves ahead. The "intelligence" consists of:

1. Minimax Algorithm: Recursive decision tree to predict opponent moves.
2. Alpha-Beta Pruning: Optimization technique that ignores tree branches that don't need to be calculated, significantly improving AI performance.
3. Heuristic Evaluation Function: A comprehensive static analysis algorithm that computes the net advantage (AI Score minus Opponent Score) by assessing:
   • Material Balance: Weighted values for each piece type.
   • Dynamic Mobility Analysis: Real-time calculation of available moves to reward board control and flexibility.
   • King Safety & Threat Detection: Penalties for checks, exposed King positions, and hanging pieces (undefended units).
4. Move Ordering Optimization: Before recursion, moves are sorted based on a preliminary heuristic (e.g., capturing high-value targets first). This maximizes the efficiency of Alpha-Beta Pruning by finding cut-offs earlier.

✨ Features

• Single Player: Play against the computer (Black pieces).
• Save/Load System: Save your match to a binary file and resume later.
• User System: User registration/login and win/loss statistics.
• Full Validation: Complete movement rules for all pieces, including Check and Checkmate detection.
• Visualization: Board rendered in the terminal using ANSI colors.

📂 Project Architecture

The code is organized into modules to facilitate maintenance and scalability:

• main.c: Entry point and main game loop.
• ia.c / ia.h: Minimax logic, heuristics, and move generation.
• regras.c / regras.h: Move validation, Check/Checkmate detection.
• tabuleiro.c / tabuleiro.h: Data structures and visual rendering.
• sistema.c / sistema.h: Menus, file handling, and authentication.
• defs.h: Global definitions and Structs.

🚀 How to Compile and Run

Prerequisites

• GCC Compiler (MinGW on Windows or native GCC on Linux).

Compiling

Since the project uses multiple files, use the following command in your terminal to compile everything together:

gcc main.c tabuleiro.c regras.c ia.c sistema.c -o chess_game

Running

# Windows
.\chess_game.exe

# Linux
./chess_game

🎮 Controls

The game uses standard algebraic notation coordinates.

• To move: Type the origin square followed by the destination square.

  • Example: e2 e4 (Moves piece from E2 to E4).

Commands:

• salvar: Saves the current game state.

• sair: Exits the application.

Developed by Guilherme Henrique.