myhunt/ruby/lib/minehunt.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

module MineHunt
  VERSION = '1.1.0'

  class Cell
    attr_accessor :mine,
                  :open

    def initialize( mine: false, open: false )
      @mine = mine
      @open = open
    end

    def explore
      @open = true

      @mine
    end
  end

  class Board
    attr_reader :width,
                :height,
                :field,
                :number_of_mines,
                :explorer_x,
                :explorer_y,
                :score

    def initialize( number_of_mines = 20, height = 8, width = 16 )
      @height = height
      @width = width
      @explorer_x = 0
      @explorer_y = 0
      @score = 1
      @field = {}
      @number_of_mines = if number_of_mines.negative? && number_of_mines > ((@height * @width) - 2)
                           20
                         else
                           number_of_mines
                         end

      @width.times do |x|
        @height.times do |y|
          @field[[x, y]] = Cell.new( open: x.zero? && y.zero? )
        end
      end

      placed_mines = 0
      while placed_mines < @number_of_mines
        coordinates = [rand( @width ), rand( @height )]
        next if coordinates == [0, 0]
        next if @field[ coordinates ].mine

        @field[ coordinates ].mine = true
        placed_mines += 1
      end
    end

    def update_explorer_location( direction )
      case direction
      when 'up'
        @explorer_y -= 1 if @explorer_y.positive?
      when 'right'
        @explorer_x += 1 if @explorer_x < (@width - 1)
      when 'down'
        @explorer_y += 1 if @explorer_y < (@height - 1)
      when 'left'
        @explorer_x -= 1 if @explorer_x.positive?
      when 'up-right'
        if @explorer_x < (@width - 1) && @explorer_y.positive?
          @explorer_x += 1
          @explorer_y -= 1
        end
      when 'down-right'
        if @explorer_x < (@width - 1) && @explorer_y < (@height - 1)
          @explorer_x += 1
          @explorer_y += 1
        end
      when 'down-left'
        if @explorer_x.positive? && @explorer_y < (@height - 1)
          @explorer_x -= 1
          @explorer_y += 1
        end
      when 'up-left'
        if @explorer_x.positive? && @explorer_y.positive?
          @explorer_x -= 1
          @explorer_y -= 1
        end
      end
    end

    def move( direction )
      update_explorer_location( direction )
      @score += 1 unless @field[[@explorer_x, @explorer_y]].open

      { dead: @field[[@explorer_x, @explorer_y]].explore,
        victory: @explorer_x == (@width - 1) && @explorer_y == (@height - 1) }
    end

    def count_nearby_mines
      counter = 0

      [@explorer_x - 1, @explorer_x, @explorer_x + 1].each do |x|
        [@explorer_y - 1, @explorer_y, @explorer_y + 1].each do |y|
          next if x.negative?
          next if y.negative?
          next if x == @width
          next if y == @height
          next if x == @explorer_x && y == @explorer_y

          counter += 1 if @field[[x, y]].mine
        end
      end

      counter
    end
  end
end