Class: Sashite::Ggn::Ruleset::Source

Inherits:
Object
  • Object
show all
Includes:
MoveValidator
Defined in:
lib/sashite/ggn/ruleset/source.rb,
lib/sashite/ggn/ruleset/source/destination.rb,
lib/sashite/ggn/ruleset/source/destination/engine.rb,
lib/sashite/ggn/ruleset/source/destination/engine/transition.rb

Overview

Represents the possible source positions for a specific piece type.

A Source instance contains all the starting positions from which a piece can move on the board. Since GGN focuses exclusively on board-to-board transformations, all source positions are regular board squares.

Examples:

Basic usage with chess king

piece_data = Sashite::Ggn.load_file('chess.json')
source = piece_data.select('CHESS:K')
destinations = source.from('e1')

Complete move evaluation workflow

piece_data = Sashite::Ggn.load_file('chess.json')
king_source = piece_data.select('CHESS:K')
destinations = king_source.from('e1')
engine = destinations.to('e2')

board_state = { 'e1' => 'CHESS:K', 'e2' => nil }
transitions = engine.where(board_state, 'CHESS')

if transitions.any?
  puts "King can move from e1 to e2"
end

Defined Under Namespace

Classes: Destination

Constant Summary

Constants included from MoveValidator

MoveValidator::GAN_SEPARATOR

Instance Method Summary collapse

Constructor Details

#initialize(data, actor:) ⇒ Source

Creates a new Source instance from movement data.

Examples:

Creating a Source instance

source_data = {
  "e1" => { "e2" => [...], "f1" => [...] },
  "d4" => { "d5" => [...], "e5" => [...] }
}
source = Source.new(source_data, actor: "CHESS:K")

Parameters:

  • data (Hash) —

    The movement data where keys are source positions (square labels) and values contain destination data.

  • actor (String) —

    The GAN identifier for this piece type

Raises:

  • (ArgumentError) —

    If data is not a Hash



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# File 'lib/sashite/ggn/ruleset/source.rb', line 50

def initialize(data, actor:)
  raise ::ArgumentError, "Expected Hash, got #{data.class}" unless data.is_a?(::Hash)

  @data = data
  @actor = actor

  freeze
end

Instance Method Details

#from(origin) ⇒ Destination

Retrieves possible destinations from a specific source position.

Examples:

Getting moves from a specific square

destinations = source.from('e1')
engine = destinations.to('e2')

Handling missing origins

begin
  destinations = source.from('invalid_square')
rescue KeyError => e
  puts "No moves from this position: #{e.message}"
end

Iterating through all possible origins

# Assuming you have access to the source data keys
available_origins = ['e1', 'd1', 'f1']  # example origins
available_origins.each do |pos|
  begin
    destinations = source.from(pos)
    puts "Piece can move from #{pos}"
    # Process destinations...
  rescue KeyError
    puts "No moves available from #{pos}"
  end
end

Parameters:

  • origin (String) —

    The source position label. Must be a regular square label (e.g., ‘e1’, ‘5i’, ‘a1’).

Returns:

  • (Destination) —

    A Destination instance containing all possible target squares and their movement conditions from this origin.

Raises:

  • (KeyError) —

    If the origin position is not found in the data



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# File 'lib/sashite/ggn/ruleset/source.rb', line 92

def from(origin)
  data = @data.fetch(origin)
  Destination.new(data, actor: @actor, origin: origin)
end