package ru.sql.forum.samples.horse;

import org.slf4j.Logger;

public class Horse {

    private Logger logger = org.slf4j.LoggerFactory.getLogger(Horse.class);

    int hourseCount = 65;
    int[][] x = new int[9][9];
    int[] is = new int[hourseCount];
    int[] js = new int[hourseCount];
    long depth = 0;
    int iStartPos = 1;
    int jStartPos = 1;

    public Horse() {
        x[iStartPos][jStartPos] = 1;
        is[1] = iStartPos;
        js[1] = jStartPos;

        logger.debug("start");

        printState();
    }

    public static void main(String args[]) {
        Horse h = new  Horse();

        h.tryHorse(2);
    }

    public boolean tryHorse(int horseIndex) {
        boolean success = true;
        int[] moving;
        int mc = 1;
        int x1;
        int y1;
        depth++;
        logger.debug("Глубина = {}", depth);

        if (horseIndex == 2) {
            x1 = iStartPos;
            y1 = jStartPos;
            is[horseIndex] = x1;
            js[horseIndex] = y1;
        }

        do {
            moving = moveHorse(mc, is[horseIndex - 1], js[horseIndex - 1]);
            if (moving[0] != 0 && moving[1] != 0) { //если можно поставить коня
                x1 = moving[0];
                y1 = moving[1];

                x[x1][y1] = horseIndex;/*ставим*/
                is[horseIndex] = x1;
                js[horseIndex] = y1;

                logger.debug("Можно !  Передвигаем коня на  x={} y={}, ход {}", x1, y1, horseIndex);

                printState();

                if (horseIndex <= 64) {
                    success = tryHorse(horseIndex + 1);
                }

                if (!success) {
                    logger.debug("Плохо !  Вынуждены убрать коня с x={} y={} ", is[horseIndex], js[horseIndex]);

                    x[is[horseIndex]][js[horseIndex]] = 0;
                    is[horseIndex] = 0;
                    js[horseIndex] = 0;
                    success = true;
                }
            }
            mc++;
            if (mc == 9) {
                success = false;
            }
        } while (!(!success || mc == 9));

        depth--;

        return success;
    }

    public int[] moveHorse(int i1, int i, int j) {
        int[] result = new int[2];
        result[0] = 0;
        result[1] = 0;
        int is;
        int js;

        logger.debug("Попытка {} из 8. проверим можно ли передвинуть с {} {} ",i1, i, j);

        if (i1 == 1 && i - 2 >= 1 && j - 1 >= 1 && x[i - 2][j - 1] == 0) {
            is = i - 2;
            js = j - 1;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 2 && i - 1 >= 1 && j - 2 >= 1 && x[i - 1][j - 2] == 0) {
            is = i - 1;
            js = j - 2;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 3 && i + 1 <= 8 && j - 2 >= 1 && x[i + 1][j - 2] == 0) {
            is = i + 1;
            js = j - 2;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 4 && i + 2 <= 8 && j - 1 >= 1 && x[i + 2][j - 1] == 0) {
            is = i + 2;
            js = j - 1;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 5 && i + 2 <= 8 && j + 1 <= 8 && x[i + 2][j + 1] == 0) {
            is = i + 2;
            js = j + 1;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 6 && i + 1 <= 8 && j + 2 <= 8 && x[i + 1][j + 2] == 0) {
            is = i + 1;
            js = j + 2;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 7 && i - 1 >= 1 && j + 2 <= 8 && x[i - 1][j + 2] == 0) {
            is = i - 1;
            js = j + 2;
            result[0] = is;
            result[1] = js;

        } else if (i1 == 8 && i - 2 >= 1 && j + 1 <= 8 && x[i - 2][j + 1] == 0) {
            is = i - 2;
            js = j + 1;
            result[0] = is;
            result[1] = js;

        }
        return result;
    }

    public void printState() {
        if(logger.isInfoEnabled()) {
            StringBuilder sb = new StringBuilder();

            for (int x = 1; x <= 8; x++) {
                for (int y = 1; y <= 8; y++) {
                    if (this.x[x][y] > 0) {
                        sb.append(this.x[x][y]).append(" ");
                    } else if (this.x[x][y] < 0) {
                        sb.append("B ");
                    } else if (this.x[x][y] == 0) {
                        sb.append("0 ");
                    }
                }
                sb.append("\n");
            }
            sb.append("\n");

            logger.info(sb.toString());
        }
    }
}