Class: ConsoleShogi::PieceMovementChecker

Inherits:
Object
  • Object
show all
Defined in:
lib/console_shogi/piece_movement_checker.rb

Instance Method Summary collapse

Constructor Details

#initialize(board:, from:, to:) ⇒ PieceMovementChecker

Returns a new instance of PieceMovementChecker.



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# File 'lib/console_shogi/piece_movement_checker.rb', line 5

def initialize(board:, from:, to:)
  @board = board
  @from = from
  @to = to
end

Instance Method Details

#can_move? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/console_shogi/piece_movement_checker.rb', line 11

def can_move?
  return false unless board.within_range?(x: to[:x], y: to[:y])

  diff = {x: to[:x] - from[:x], y: to[:y] - from[:y]}

  return false if from_piece.moves.none? {|m| m[:x] == diff[:x] && m[:y] == diff[:y] }

  return false if from_piece.teban == to_piece.teban

  return true unless from_piece.can_move_long_distance?

  distance = (diff[:x].nonzero? || diff[:y]).abs
  element = [diff[:x] / distance, diff[:y] / distance]

  1.upto(distance - 1) do |d|
    piece = board.fetch_piece(x: from[:x] + element[0] * d, y: from[:y] + element[1] * d)

    return false unless piece.none?
  end

  true
end