// Antoine CRETUAL, Lukian LEIZOUR, 14/02/2024

public class Universe {
    // Atributes

    private int[][] grid;
    private int length, height;
    private int boxes_to_fill;

    // Constructors

    public Universe(int length, int height, int i_start, int j_start, int dir_start) {
        this.grid = new int[height][length];
        this.height = height;
        this.length = length;

        int i, j;
        for (i = 1; i < this.height - 1; i++) {
            for (j = 1; j < this.length - 1; j++) {
                this.grid[i][j] = 0;
            }
        }

        for (i = 0; i < this.height; i++) {
            this.grid[i][0] = -1;
            this.grid[i][length - 1] = -1;
        }

        for (j = 0; j < this.length; j++) {
            this.grid[0][j] = -1;
            this.grid[height - 1][j] = -1;
        }

        this.grid[i_start][j_start] = dir_start;

        this.boxes_to_fill = 0;

        for (i = 1; i < this.height - 1; i++) {
            for (j = 1; j < this.length - 1; j++) {
                if (this.grid[i][j] == 0) this.boxes_to_fill++;
            }
        }
    }

    // Methods

    public void addObstacle(int pos_i, int pos_j) {
        if (this.grid[pos_i][pos_j] == 0) {
            this.grid[pos_i][pos_j] = -1;
        }
        else {}
    }

    public int possibleChoices(Situation s) {
        int i = s.pos_i;
        int j = s.pos_j;
        int d = s.direction;
        int c = s.nb_choix;

        switch (c) {
            case 0: {
                switch (d) {
                    case 10:  // north
                        if (this.grid[i - 1][j] == 0)      return 1;    // front
                        else if (this.grid[i][j - 1] == 0) return 2;    // left
                        else if (this.grid[i][j + 1] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 11:  // south
                        if (this.grid[i + 1][j] == 0)      return 1;    // front
                        else if (this.grid[i][j + 1] == 0) return 2;    // left
                        else if (this.grid[i][j - 1] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 12:  // east
                        if (this.grid[i][j + 1] == 0)      return 1;    // front
                        else if (this.grid[i - 1][j] == 0) return 2;    // left
                        else if (this.grid[i + 1][j] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 13:  //west
                        if (this.grid[i][j - 1] == 0)      return 1;    // front
                        else if (this.grid[i + 1][j] == 0) return 2;    // left
                        else if (this.grid[i - 1][j] == 0) return 3;    // right
                        else return -1;                                 // back

                    default: {}
                }
            }
            case 1: {
                switch (d) {
                    case 10:  // north
                        if (this.grid[i][j - 1] == 0)      return 2;    // left
                        else if (this.grid[i][j + 1] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 11:  // south
                        if (this.grid[i][j + 1] == 0)      return 2;    // left
                        else if (this.grid[i][j - 1] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 12:  // east
                        if (this.grid[i - 1][j] == 0)      return 2;    // left
                        else if (this.grid[i + 1][j] == 0) return 3;    // right
                        else return -1;                                 // back

                    case 13:  //west
                        if (this.grid[i + 1][j] == 0)      return 2;    // left
                        else if (this.grid[i - 1][j] == 0) return 3;    // right
                        else return -1;                                 // back

                    default: {}
                }
            }
            case 2: {
                switch (d) {
                    case 10:  // north
                        if (this.grid[i][j + 1] == 0)      return 3;    // right
                        else return -1;                                 // back

                    case 11:  // south
                        if (this.grid[i][j - 1] == 0)      return 3;    // right
                        else return -1;                                 // back

                    case 12:  // east
                        if (this.grid[i + 1][j] == 0)      return 3;    // right
                        else return -1;                                 // back

                    case 13:  //west
                        if (this.grid[i - 1][j] == 0)      return 3;    // right
                        else return -1;                                 // back


                    default: {}
                }
            }
            case 3:
                return -1; 

            default: return -1;
        } 
    }

    public boolean canEvolve(Situation s) {
        return possibleChoices(s) != -1; 
    }

    public Situation evolve(Situation s) {
        int i = s.pos_i;
        int j = s.pos_j;
        int d = s.direction;
        int c = possibleChoices(s);

        // adding the miror

        /*switch (c) {
            case 1:
                this.grid[i][j] = 1;
                break;

            case 2:
                this.grid[i][j] = 2;
                break;

            case 3:
                this.grid[i][j] = 3;
                break;

            default:
        }*/

        if (c == 1 && (d == 10 || d == 11)) this.grid[i][j] = 1;
        if (c == 1 && (d == 12 || d == 13)) this.grid[i][j] = 2;
        if ((c == 3 && d == 10) || (c == 3 && d == 11) || (c == 2 && d == 12) || (c == 2 && d == 13)) this.grid[i][j] = 3;
        if ((c == 2 && d == 10) || (c == 2 && d == 11) || (c == 3 && d == 12) || (c == 3 && d == 13)) this.grid[i][j] = 4;

        // changing the position of the situation

        if (c == 1 && d == 10 || c == 2 && d == 12 || c == 3 && d == 13) {
            i --;
            d = 10;
        }
        else if (c == 1 && d == 11 || c == 2 && d == 13 || c == 3 && d == 12) {
            i ++;
            d = 11;
        }
        else if (c == 1 && d == 12 || c == 2 && d == 11 || c == 3 && d == 10) {
            j ++;
            d = 12;
        }
        else if (c == 1 && d == 13 || c == 2 && d == 10 || c == 3 && d == 11) {
            j --;
            d = 13;
        }

        this.boxes_to_fill--;

        return new Situation(i, j, d, 0);
    }

    public void reset(Situation s) {
        this.grid[s.pos_i][s.pos_j] = 0;
        this.boxes_to_fill++;
    }

    public boolean isSolved() {
        return this.boxes_to_fill - 1 == 0;
    }

    /*public Situation restore(Situation current, Situation prev) {
        
    }*/

    public void print() {
        int i, j;
        for (i = 0; i < this.height; i++) {
            for (j = 0; j < this.length; j++) {
                switch (this.grid[i][j]) {
                    case -1: 
                        System.out.printf("  X");
                        break;

                    case 0: 
                        System.out.printf("   ");
                        break;

                    case 1: 
                        System.out.printf("  |");
                        break;

                    case 2: 
                        System.out.printf("  -");
                        break;

                    case 3: 
                        System.out.printf("  /");
                        break;

                    case 4: 
                        System.out.printf("  \\");
                        break;

                    case 10: 
                        System.out.printf("  ^");
                        break;

                    case 11: 
                        System.out.printf("  v");
                        break;

                    case 12: 
                        System.out.printf("  >");
                        break;

                    case 13: 
                        System.out.printf("  <");
                        break;

                    default:
                        System.out.printf("%3d", this.grid[i][j]);

                }
            }
            System.out.print("\n");
        }
    }
}