Node JS Console hat finder game

node-hat-finder.js

const prompt = require('prompt-sync')({ sigint: true });

const hat = '^';
const hole = 'O';
const fieldCharacter = '░';
const pathCharacter = '*';

class Field {
  constructor(field) {
    this.field = field;
    this.positionX = 0;
    this.positionY = 0;
    this.rows = field.length - 1;
    this.columns = field[0].length - 1;
    this.path = [[0, 0]];
    this.win = false;
    this.lose = false;
  }
  fillPath(x, y) {
    this.field[x][y] = pathCharacter;
  }
  print() {
    const fieldBoardStr = this.field.reduce((accum, curr) => accum + curr.join('') + '\n', '');
    console.log(fieldBoardStr);
  }
  checkMove(newPositionX, newPositionY) {
    if (newPositionX < 0 || newPositionX > this.rows || newPositionY < 0 || newPositionY > this.columns) {
      throw new Error('You are out of the field');
    } else {
      if (this.path.length > 1 && newPositionX === this.path[this.path.length - 2][0] && newPositionY === this.path[this.path.length - 2][1]) {
        throw new Error('You can\'t go back!');
      }
      const nextPathObj = this.field[newPositionY][newPositionX];
      if (nextPathObj === hole) throw new Error('You fall down in a hole!');
      if (nextPathObj === pathCharacter) return false;
      if (nextPathObj === hat) return true;
    }
  }
  static generateField(height, width, percentage = 0) {
    // Initialize the number of hats, holes and blanks that should fill the field
    let hats = 1;
    let holes = (percentage) ? height * width * percentage / 100 : 1;
    let blanks = width * height - holes - hats - 1; // Minus one because of the first path character
    let field = [];
    const pickOne = () => {
      const numberOfItemsRemaining = hats + holes + blanks;
      if (numberOfItemsRemaining) {
        const newPick = Math.floor(Math.random() * numberOfItemsRemaining + 1);
        // The program selects an item based on the number of items remaining
        // This method allows that when the program pick an item for the field,
        // the probability of picking a certain item was based in the in the remaining
        // number of items of that particular item.
        if (newPick <= hats) {
          hats--;
          return hat;
        }
        if (newPick <= hats + holes) {
          holes--;
          return hole;
        }
        if (newPick <= numberOfItemsRemaining) {
          blanks--;
          return fieldCharacter;
        }  
      }
      // By default returns the field character (just in case ;) )
      return fieldCharacter;
    }

    for (let i = 0; i < height; i++) {
      const line = [];
      for (let j = 0; j < width; j++) {
        if (i === 0 && j === 0) line.push(pathCharacter);
        else line.push(pickOne());
      }
      field.push(line);
    }
    return field;
  }
  // 0 -> left - 1 -> Right - 2 -> Up - 3 -> Down
  movePlayer(direction) {
    const prevPosition = [this.positionX, this.positionY];
    let newPositionX = this.positionX;
    let newPositionY = this.positionY;
    switch (direction) {
      case 0:
        newPositionX = this.positionX - 1;
        break;
      case 1:
        newPositionX = this.positionX + 1;
        break;
      case 2:
        newPositionY = this.positionY - 1;
        break;
      case 3:
        newPositionY = this.positionY + 1;
        break;
      default:
        break;
    }
    try {
      const winner = this.checkMove(newPositionX, newPositionY);
      if (!winner) {
        this.positionX = newPositionX;
        this.positionY = newPositionY;
        if (prevPosition[0] !== this.positionX || prevPosition[1] !== this.positionY) {
          this.path.push([this.positionX, this.positionY]);
          this.field[this.positionY][this.positionX] = pathCharacter;
        }
      } else {
        this.win = true;
        console.log("You find the hat!")
      }
    } catch (err) {
      this.lose = true;
      console.log(err.message);
    }
  }
}

const newField = Field.generateField(5, 6, 20);
const myField = new Field(newField);

while (!myField.win && !myField.lose) {
  // console.clear();
  myField.print();
  const direction = prompt(
    `Which direction you like to move?:
      0 -> left |||| 1 -> Right |||| 2 -> Up |||| 3 -> Down: `);
  myField.movePlayer(Number.parseInt(direction));
}