module AsyncDuel

# File lib/async_duel.rb, line 47
def accept(game:, user:)
  return { error: "No pending challenge." } unless game && game["stage"] == "lobby"
  return { error: "That challenge is not for you." } unless GameStore.same_nick?(user, game["target"])

  game = game.dup
  game["stage"] = "active"
  { game: game }
end

# File lib/async_duel.rb, line 30
def challenge(game:, challenger:, target:, channel_users:)
  normalized_target = GameStore.norm_nick(target)
  unless channel_users.any? { |nick| GameStore.same_nick?(nick, normalized_target) }
    return { error: "#{target} is not in this channel." }
  end
  return { error: "You cannot challenge yourself." } if GameStore.same_nick?(challenger, target)

  {
    game: {
      "stage" => "lobby",
      "challenger" => GameStore.norm_nick(challenger),
      "target" => normalized_target,
      "turn" => GameStore.norm_nick(challenger)
    }
  }
end

# File lib/async_duel.rb, line 56
def decline(game:, user:)
  return { error: "No pending challenge." } unless game && game["stage"] == "lobby"
  return { error: "That challenge is not for you." } unless GameStore.same_nick?(user, game["target"])

  { cleared: true }
end

# File lib/async_duel.rb, line 67
def opponent(game, user)
  if GameStore.same_nick?(user, game["challenger"])
    game["target"]
  else
    game["challenger"]
  end
end

# File lib/async_duel.rb, line 8
def parse_base(text, usage:)
  parts = text.to_s.strip.split(/\s+/)
  return { action: :help } if parts.empty?

  case parts[0].downcase
  when "help"
    { action: :help }
  when "challenge"
    return { error: usage } if parts.length < 2

    { action: :challenge, target: parts[1] }
  when "accept"
    { action: :accept }
  when "decline"
    { action: :decline }
  when "status"
    { action: :status }
  else
    { action: :unknown, tail: parts }
  end
end

# File lib/async_duel.rb, line 63
def player?(game, user)
  GameStore.same_nick?(user, game["challenger"]) || GameStore.same_nick?(user, game["target"])
end