export class Mask {
  mask: boolean[][] = [];

  constructor(width: number, height: number) {
    for (let x = 0; x < width; x++) {
      this.mask.push(Array(height).fill(false));
    }
  }

  static from_string(mask_string: string): Mask {
    // mask_string: '\n+++\n+++\n'
    const rows = mask_string.trim().split('\n');
    // rows: ['+++', '+++']

    const mask = new Mask(rows[0].length, rows.length);

    for (let y = 0; y < rows.length; y++) {
      const row = rows[y];
      for (let x = 0; x < row.length; x++) {
        const cell = row[x].toLowerCase();
        if (cell == '+' || cell == 'x') {
          mask.set(x, y, true);
        }
      }
    }

    return mask;
  }

  set(x: number, y: number, val: boolean) {
    this.mask[x][y] = val;
  }

  update(x: number, y: number, src: Mask) {
    for (let xi = 0; xi < src.mask.length; xi++) {
      const col = src.mask[xi];
      for (let yi = 0; yi < col.length; yi++) {
        this.set(x + xi, y + yi, col[yi]);
      }
    }
  }
}