module LolcatRunner

# File lib/lolcat_runner.rb, line 29
def available?(executable: default_executable)
  executable.call(BIN)
end

# File lib/lolcat_runner.rb, line 37
def build_argv(tokens)
  argv = [BIN]
  tokens = Array(tokens).map(&:to_s)
  index = 0
  while index < tokens.length
    token = tokens[index]
    spec = ALLOWED_FLAGS[token]
    return { error: "Unknown lolcat option #{token.inspect}." } unless spec

    argv << token
    index += 1
    next if spec == :flag

    value = tokens[index]
    return { error: "Missing value for #{token}." } if value.nil? || value.empty?

    case spec
    when :numeric
      return { error: "Invalid number for #{token}." } unless value.match?(/\A-?\d+(?:\.\d+)?\z/)

      argv << value
    when :integer
      return { error: "Invalid integer for #{token}." } unless value.match?(/\A-?\d+\z/)

      argv << value
    end
    index += 1
  end

  argv << "-f" unless argv.include?("-f") || argv.include?("--force")
  { argv: argv }
end

# File lib/lolcat_runner.rb, line 33
def default_argv
  DEFAULT_ARGV.dup
end

# File lib/lolcat_runner.rb, line 95
def default_executable
  lambda do |bin|
    ENV.fetch("PATH", "").split(File::PATH_SEPARATOR).any? do |dir|
      path = File.join(dir, bin)
      File.file?(path) && File.executable?(path)
    end
  end
end

# File lib/lolcat_runner.rb, line 89
def default_run
  lambda do |argv, stdin_data:|
    Open3.capture3(*argv, stdin_data: stdin_data)
  end
end

# File lib/lolcat_runner.rb, line 70
def run(text, argv: default_argv, timeout: DEFAULT_TIMEOUT, run: default_run)
  return { error: "lolcat not installed." } unless available?

  stdout, _stderr, status = run_with_timeout(run, argv, text.to_s, timeout: timeout)
  return { error: "lolcat failed." } unless status.success?

  { output: stdout }
rescue Timeout::Error
  { error: "lolcat timed out." }
rescue StandardError
  { error: "lolcat failed." }
end

# File lib/lolcat_runner.rb, line 83
def run_with_timeout(run, argv, stdin_data, timeout:)
  Timeout.timeout(timeout) do
    run.call(argv, stdin_data: stdin_data)
  end
end