ia.js

getBestColumnForCpu() {
    const winnerColumn = this.getWinnerColumn(this.board, this.currentPlayer);
    if (winnerColumn !== -1) {
        console.log("Cpu chooses winner column");
        return winnerColumn;
    }
    // Check if adversary wins in the next move, if so, we take it
    const adversary = this.getAdversary(this.currentPlayer);

    const winnerColumnForAdversary = this.getWinnerColumn(this.board, adversary);
    if (winnerColumnForAdversary !== -1) {
        console.log("Cpu chooses take adversary's victory");
        return winnerColumnForAdversary;
    }
    const cpuStats = this.getColumnWithHighestScore(this.currentPlayer, this.board);
    const adversaryStats = this.getColumnWithHighestScore(adversary, this.board);
    console.log({ adversaryStats });
    console.log({ cpuStats });
    if (adversaryStats.highestCount > cpuStats.highestCount) {
        console.log("CPU chooses take adversary highest score");
        // We take the adversary's best move if it is higher than CPU's
        return adversaryStats.columnIndex;
    } else if (cpuStats.highestCount > 1) {
        console.log("CPU chooses highest count");
        return cpuStats.columnIndex;
    }
    const centralColumn = this.getCentralColumn(this.board);
    if (centralColumn !== -1) {
        console.log("CPU Chooses central column");
        return centralColumn;
    }
    // Finally we return a random column
    console.log("CPU chooses random column");
    return this.getRandomColumn(this.board);

},
getWinnerColumn(board, player) {
    for (let i = 0; i < COLUMNS; i++) {
        const boardClone = JSON.parse(JSON.stringify(board));
        const firstEmptyRow = this.getFirstEmptyRow(i, boardClone);
        //Proceed only if row is ok
        if (firstEmptyRow !== -1) {
            boardClone[firstEmptyRow][i] = player;

            // If this is winner, return the column
            if (this.isWinner(player, boardClone)) {
                return i;
            }
        }
    }
    return -1;
},
getColumnWithHighestScore(player, board) {
    const returnObject = {
        highestCount: -1,
        columnIndex: -1,
    };
    for (let i = 0; i < COLUMNS; i++) {
        const boardClone = JSON.parse(JSON.stringify(board));
        const firstEmptyRow = this.getFirstEmptyRow(i, boardClone);
        if (firstEmptyRow !== -1) {
            boardClone[firstEmptyRow][i] = player;
            const firstFilledRow = this.getFirstFilledRow(i, boardClone);
            if (firstFilledRow !== -1) {
                let count = 0;
                count = this.countUp(i, firstFilledRow, player, boardClone);
                if (count > returnObject.highestCount) {
                    returnObject.highestCount = count;
                    returnObject.columnIndex = i;
                }
                count = this.countRight(i, firstFilledRow, player, boardClone);
                if (count > returnObject.highestCount) {
                    returnObject.highestCount = count;
                    returnObject.columnIndex = i;
                }
                count = this.countUpRight(i, firstFilledRow, player, boardClone);
                if (count > returnObject.highestCount) {
                    returnObject.highestCount = count;
                    returnObject.columnIndex = i;
                }
                count = this.countDownRight(i, firstFilledRow, player, boardClone);
                if (count > returnObject.highestCount) {
                    returnObject.highestCount = count;
                    returnObject.columnIndex = i;
                }
            }
        }
    }
    return returnObject;
},
getRandomColumn(board) {
    while (true) {
        const boardClone = JSON.parse(JSON.stringify(board));
        const randomColumnIndex = this.getRandomNumberBetween(0, COLUMNS - 1);
        const firstEmptyRow = this.getFirstEmptyRow(randomColumnIndex, boardClone);
        if (firstEmptyRow !== -1) {
            return randomColumnIndex;
        }
    }
},
getCentralColumn(board) {
    const boardClone = JSON.parse(JSON.stringify(board));
    const centralColumn = parseInt((COLUMNS - 1) / 2);
    if (this.getFirstEmptyRow(centralColumn, boardClone) !== -1) {

        return centralColumn;
    }
    return -1;
},