Class: PGN::Game

Inherits:
Object
  • Object
show all
Defined in:
lib/pgn/game.rb

Overview

Game holds all of the information about a game. It is either the result of parsing a PGN file, or created by hand.

A Game has an interactive #play method, and can also return a list of positions in Position format or FEN.

Constant Summary collapse

LEFT = 
%r{(a|\x1B\[D)\z}
RIGHT = 
%r{(d|\x1B\[C)\z}
EXIT = 
%r{(q|\x03)\z}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(moves, tags = nil, result = nil) ⇒ Game

Returns a new instance of Game.

Parameters:

  • moves (Array<String>) —

    a list of moves in SAN

  • tags (Hash<String, String>) (defaults to: nil) —

    metadata about the game

  • result (String) (defaults to: nil) —

    the outcome of the game



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# File 'lib/pgn/game.rb', line 63

def initialize(moves, tags = nil, result = nil)
  self.moves  = moves
  self.tags   = tags
  self.result = result
end

Instance Attribute Details

#moves ⇒ Array<String>

Returns a list of the moves in standard algebraic notation.

Examples:

game.moves #=> ["e4", "c5", "Nf3", "d6", "d4", "cxd4"]

Returns:

  • (Array<String>) —

    a list of the moves in standard algebraic notation



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# File 'lib/pgn/game.rb', line 52

class Game
  attr_accessor :tags, :moves, :result

  LEFT  = %r{(a|\x1B\[D)\z}
  RIGHT = %r{(d|\x1B\[C)\z}
  EXIT  = %r{(q|\x03)\z}

  # @param moves [Array<String>] a list of moves in SAN
  # @param tags [Hash<String, String>] metadata about the game
  # @param result [String] the outcome of the game
  #
  def initialize(moves, tags = nil, result = nil)
    self.moves  = moves
    self.tags   = tags
    self.result = result
  end

  # @param moves [Array<String>] a list of moves in SAN
  #
  # Standardize castling moves to use O's instead of 0's
  #
  def moves=(moves)
    @moves = moves.map do |m|
      if m.is_a? String
        MoveText.new(m.gsub("0", "O"))
      else
        MoveText.new(m.notation.gsub("0", "O"), m.annotation, m.comment, m.variations)
      end
    end
  end

  def starting_position
    @starting_position ||= if fen = (self.tags && self.tags['FEN'])
                             PGN::FEN.new(fen).to_position
                           else 
                             PGN::Position.start 
                           end 
  end 

  # @return [Array<PGN::Position>] list of the {PGN::Position}s in the game
  #
  def positions
    @positions ||= begin
      position = starting_position
      arr = [position]
      self.moves.each do |move|
        new_pos = position.move(move.notation)
        arr << new_pos
        position = new_pos
      end
      arr
    end
  end

  # @return [Array<String>] list of the fen representations of the positions
  #
  def fen_list
    self.positions.map {|p| p.to_fen.inspect }
  end

  # Interactively step through the game
  #
  # Use +d+ to move forward, +a+ to move backward, and +^C+ to exit.
  #
  def play
    index = 0
    hist = Array.new(3, "")

    loop do
      puts "\e[H\e[2J"
      puts self.positions[index].inspect
      hist[0..2] = (hist[1..2] << STDIN.getch)

      case hist.join
      when LEFT
        index -= 1 if index > 0
      when RIGHT
        index += 1 if index < self.moves.length
      when EXIT
        break
      end
    end
  end
end

#result ⇒ String

Returns the outcome of the game.

Examples:

game.result #=> "1-0"

Returns:

  • (String) —

    the outcome of the game



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# File 'lib/pgn/game.rb', line 52

class Game
  attr_accessor :tags, :moves, :result

  LEFT  = %r{(a|\x1B\[D)\z}
  RIGHT = %r{(d|\x1B\[C)\z}
  EXIT  = %r{(q|\x03)\z}

  # @param moves [Array<String>] a list of moves in SAN
  # @param tags [Hash<String, String>] metadata about the game
  # @param result [String] the outcome of the game
  #
  def initialize(moves, tags = nil, result = nil)
    self.moves  = moves
    self.tags   = tags
    self.result = result
  end

  # @param moves [Array<String>] a list of moves in SAN
  #
  # Standardize castling moves to use O's instead of 0's
  #
  def moves=(moves)
    @moves = moves.map do |m|
      if m.is_a? String
        MoveText.new(m.gsub("0", "O"))
      else
        MoveText.new(m.notation.gsub("0", "O"), m.annotation, m.comment, m.variations)
      end
    end
  end

  def starting_position
    @starting_position ||= if fen = (self.tags && self.tags['FEN'])
                             PGN::FEN.new(fen).to_position
                           else 
                             PGN::Position.start 
                           end 
  end 

  # @return [Array<PGN::Position>] list of the {PGN::Position}s in the game
  #
  def positions
    @positions ||= begin
      position = starting_position
      arr = [position]
      self.moves.each do |move|
        new_pos = position.move(move.notation)
        arr << new_pos
        position = new_pos
      end
      arr
    end
  end

  # @return [Array<String>] list of the fen representations of the positions
  #
  def fen_list
    self.positions.map {|p| p.to_fen.inspect }
  end

  # Interactively step through the game
  #
  # Use +d+ to move forward, +a+ to move backward, and +^C+ to exit.
  #
  def play
    index = 0
    hist = Array.new(3, "")

    loop do
      puts "\e[H\e[2J"
      puts self.positions[index].inspect
      hist[0..2] = (hist[1..2] << STDIN.getch)

      case hist.join
      when LEFT
        index -= 1 if index > 0
      when RIGHT
        index += 1 if index < self.moves.length
      when EXIT
        break
      end
    end
  end
end

#tags ⇒ Hash<String, String>

Returns metadata about the game.

Examples:

game.tags #=> {"White" => "Kasparov", "Black" => "Deep Blue"}

Returns:

  • (Hash<String, String>) —

    metadata about the game



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# File 'lib/pgn/game.rb', line 52

class Game
  attr_accessor :tags, :moves, :result

  LEFT  = %r{(a|\x1B\[D)\z}
  RIGHT = %r{(d|\x1B\[C)\z}
  EXIT  = %r{(q|\x03)\z}

  # @param moves [Array<String>] a list of moves in SAN
  # @param tags [Hash<String, String>] metadata about the game
  # @param result [String] the outcome of the game
  #
  def initialize(moves, tags = nil, result = nil)
    self.moves  = moves
    self.tags   = tags
    self.result = result
  end

  # @param moves [Array<String>] a list of moves in SAN
  #
  # Standardize castling moves to use O's instead of 0's
  #
  def moves=(moves)
    @moves = moves.map do |m|
      if m.is_a? String
        MoveText.new(m.gsub("0", "O"))
      else
        MoveText.new(m.notation.gsub("0", "O"), m.annotation, m.comment, m.variations)
      end
    end
  end

  def starting_position
    @starting_position ||= if fen = (self.tags && self.tags['FEN'])
                             PGN::FEN.new(fen).to_position
                           else 
                             PGN::Position.start 
                           end 
  end 

  # @return [Array<PGN::Position>] list of the {PGN::Position}s in the game
  #
  def positions
    @positions ||= begin
      position = starting_position
      arr = [position]
      self.moves.each do |move|
        new_pos = position.move(move.notation)
        arr << new_pos
        position = new_pos
      end
      arr
    end
  end

  # @return [Array<String>] list of the fen representations of the positions
  #
  def fen_list
    self.positions.map {|p| p.to_fen.inspect }
  end

  # Interactively step through the game
  #
  # Use +d+ to move forward, +a+ to move backward, and +^C+ to exit.
  #
  def play
    index = 0
    hist = Array.new(3, "")

    loop do
      puts "\e[H\e[2J"
      puts self.positions[index].inspect
      hist[0..2] = (hist[1..2] << STDIN.getch)

      case hist.join
      when LEFT
        index -= 1 if index > 0
      when RIGHT
        index += 1 if index < self.moves.length
      when EXIT
        break
      end
    end
  end
end

Instance Method Details

#fen_list ⇒ Array<String>

Returns list of the fen representations of the positions.

Returns:

  • (Array<String>) —

    list of the fen representations of the positions



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# File 'lib/pgn/game.rb', line 108

def fen_list
  self.positions.map {|p| p.to_fen.inspect }
end

#play ⇒ Object

Interactively step through the game

Use d to move forward, a to move backward, and ^C to exit.



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# File 'lib/pgn/game.rb', line 116

def play
  index = 0
  hist = Array.new(3, "")

  loop do
    puts "\e[H\e[2J"
    puts self.positions[index].inspect
    hist[0..2] = (hist[1..2] << STDIN.getch)

    case hist.join
    when LEFT
      index -= 1 if index > 0
    when RIGHT
      index += 1 if index < self.moves.length
    when EXIT
      break
    end
  end
end

#positions ⇒ Array<PGN::Position>

Returns list of the Positions in the game.

Returns:



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# File 'lib/pgn/game.rb', line 93

def positions
  @positions ||= begin
    position = starting_position
    arr = [position]
    self.moves.each do |move|
      new_pos = position.move(move.notation)
      arr << new_pos
      position = new_pos
    end
    arr
  end
end

#starting_position ⇒ Object 



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# File 'lib/pgn/game.rb', line 83

def starting_position
  @starting_position ||= if fen = (self.tags && self.tags['FEN'])
                           PGN::FEN.new(fen).to_position
                         else 
                           PGN::Position.start 
                         end 
end