evaluation.cpp

#include "evaluation.hpp"
#include "patterns.hpp"
#include "Pattern.hpp"
#include <string>
#include <iostream>


int evaluate(move m){
	int score = 0;
	Board position =  board_after_move(m);
	U64 *bitboards = position.get_bitboards();
	int side = m.side;
	int won = hasWon(bitboards[side]);

	if(won == 1){
		score = 10000;
	}
	
	else{
		score += determineScore(bitboards, side);
		score -= determineScore(bitboards, 1 - side);
		
	}

	return score;
}

int hasWon(U64 bitboard){
	for (int i = 0; i < 4; i++){
		  if( pattern_match(bitboard, winning_patterns[i]) > 0){
			  return 1;
		  }
	}
	return 0;
}




int determineScore(U64 *bitboards, int side){
	U64 playingBB = bitboards[side];
	U64 opponentBB = bitboards[1-side];

	int score = 0;


	// For a straight four : win at the next round
	for (int i = 0; i < 4; i++){
		score += 50 * pattern_match(playingBB, patterns_length_4_playing[i], opponentBB, patterns_length_4_opponent_v1[i]);
		score += 50 * pattern_match(playingBB, patterns_length_4_playing[i], opponentBB, patterns_length_4_opponent_v2[i]);
	}

	// For a broken four : may win at the next round
	for (int i = 0; i < 12; i++){
		score += 50 * pattern_match(playingBB, patterns_length_4_broken[i], opponentBB, patterns_length_4_broken_opponent[i]);
	}

	// For a straight three : win in two plays
	for (int i = 0; i < 4; i++){
		score += 30 * pattern_match(playingBB, patterns_length_3[i], opponentBB, patterns_length_3_opponent[i]);
	}

	// For a broken three
	for (int i = 0; i < 8; i++){
		score += 30 * pattern_match(playingBB, patterns_length_3_broken[i]);
	}

	// For two aligned
	for (int i = 0; i < 4; i++){
		score += 5 * pattern_match(playingBB, patterns_length_2[i]);
	}

	// For single or isolated points
	U64 index = 0x1Ull;
	for(int i = 0; i  < 63; i++){
		if((U64)(index & playingBB) == index)
			score += value_coef[i];
		index <<=1;
	}

	return score;
}

int is_game_over(Board board){
	U64* bitboards = board.get_bitboards();
	if(hasWon(bitboards[WHITE])){
		board.print_board();
		std::cout << "O's won the game, congratulations !" << std::endl;
	   return 1;	
	}
	if(hasWon(bitboards[BLACK])){
		board.print_board();
		std::cout << "X's won the game, congratulations !" << std::endl;
		return 1;
	}
	if(~bitboards[3] == 1ULL){
		board.print_board();
		std::cout << "The game is a draw." << std::endl;
		return 1;
	}
	return 0;
}