Module: Stockshark::UciProtocol

Defined in:
lib/stockshark/uci_protocol.rb

Overview

Pure parsing of UCI protocol text into structured Ruby data. No IO, no process — every method here is a plain string in, hash/nil out, which is what makes it trivially unit-testable without ever spawning a real engine. Scores are returned exactly as the engine reports them: relative to whichever side is to move in the position that was analyzed. Flipping that to a fixed perspective is a game-aware decision this module deliberately knows nothing about — that's up to whatever calls this gem.

Class Method Summary collapse

Class Method Details

.parse_bestmove(line) ⇒ Object

"bestmove e2e4 ponder e7e5" => { best_move: "e2e4", ponder: "e7e5" }



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# File 'lib/stockshark/uci_protocol.rb', line 23

def parse_bestmove(line)
  match = line.match(/\Abestmove (?<best_move>\S+)(?: ponder (?<ponder>\S+))?/)
  return nil unless match

  { best_move: match[:best_move], ponder: match[:ponder] }
end

.parse_id(line) ⇒ Object

"id name Stockfish 16" => { name: "Stockfish 16" } "id author ..." and any other id line => nil (not what we need).



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# File 'lib/stockshark/uci_protocol.rb', line 15

def parse_id(line)
  match = line.match(/\Aid name (?<name>.+)\z/)
  return nil unless match

  { name: match[:name] }
end

.parse_info(line) ⇒ Object

"info depth 20 seldepth 28 multipv 1 score cp 34 nodes 12345 pv e2e4 e7e5 g1f3" => { depth: 20, multipv: 1, score_cp: 34, score_mate: nil, pv: ["e2e4", "e7e5", "g1f3"] } "info depth 12 multipv 2 score mate -3 pv ... " => { depth: 12, multipv: 2, score_cp: nil, score_mate: -3, pv: [...] } "info depth 0 score mate 0" (position has no legal moves — checkmate; stalemate reports "score cp 0" instead — neither carries a pv, since there's no move to report) => { depth: 0, multipv: 1, score_cp: nil, score_mate: 0, pv: [] } Returns nil for info lines that don't carry a score at all (plain "info string ..." diagnostics, "info currmove ...", etc.) — callers should just skip those.



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# File 'lib/stockshark/uci_protocol.rb', line 41

def parse_info(line)
  return nil unless line.start_with?("info ") && line.match?(/\bscore (?:cp|mate) -?\d+/)

  depth = line[/\bdepth (\d+)/, 1]
  return nil unless depth

  pv = line[/ pv (.+)\z/, 1]

  {
    depth: depth.to_i,
    multipv: (line[/\bmultipv (\d+)/, 1] || "1").to_i,
    score_cp: line[/\bscore cp (-?\d+)/, 1]&.to_i,
    score_mate: line[/\bscore mate (-?\d+)/, 1]&.to_i,
    pv: pv ? pv.split(" ") : []
  }
end