class Alda::REPL

# File lib/alda-rb/repl.rb, line 249
def initialize color: true, preview: true, reline: true, **opts
  @score = TempScore.new self
  @binding = @score.get_binding
  # IRB once changed the API of RubyLex#initialize. Take care of that.
  @lex = RubyLex.new *(RubyLex.instance_method(:initialize).arity == 0 ? [] : [@binding])
  @color = color
  @preview = preview
  @reline = reline
  setup_repl opts
end

# File lib/alda-rb/repl.rb, line 506
def clear_history
  if Alda.v1?
    @history = StringIO.new
  else
    try_command { message :new_score }
  end
  nil
end

# File lib/alda-rb/repl.rb, line 492
def history
  if Alda.v1?
    @history
  else
    try_command { message :score_text }
  end
end

# File lib/alda-rb/repl.rb, line 320
def message op, **params
  result = raw_message op: Alda::Utils.snake_to_slug(op), **params
  result.transform_keys! { Alda::Utils.slug_to_snake _1 }
  if (status = result.delete :status).include? 'error'
    raise Alda::NREPLServerError.new @host, @port, result.delete(:problems), status
  end
  case result.size
  when 0 then nil
  when 1 then result.values.first
  else result
  end
end

# File lib/alda-rb/repl.rb, line 452
def play_score code
  if Alda.v1?
    Alda.play code: code, history: @history
    @history.puts code
  else
    message :eval_and_play, code: code
  end
end

# File lib/alda-rb/repl.rb, line 411
def process_rb_code code
  @score.clear
  begin
    @binding.eval code
  rescue StandardError, ScriptError, Interrupt => e
    $stderr.print e.full_message
    return true
  rescue SystemExit
    return false
  end
  code = @score.events_alda_codes
  unless code.empty?
    $stdout.puts @color ? code.yellow : code
    try_command { play_score code }
  end
  true
end

# File lib/alda-rb/repl.rb, line 296
def raw_message contents
  Alda::GenerationError.assert_generation [:v2]
  contents = JSON.parse contents if contents.is_a? String
  @socket.write contents.bencode
  @bencode_parser.parse!
end

# File lib/alda-rb/repl.rb, line 362
def rb_code
  result = ''
  indent = 0
  begin
    result.concat readline(indent).tap { return unless _1 }, ?\n
    # IRB once changed the API of RubyLex#check_state. Take care of that.
    opts = @lex.method(:check_state).arity.positive? ? {} : { context: @binding }
    ltype, indent, continue, block_open = @lex.check_state result, **opts
  rescue Interrupt
    $stdout.puts
    return ''
  end while ltype || indent.nonzero? || continue || block_open
  result
end

# File lib/alda-rb/repl.rb, line 387
def readline indent = 0
  prompt = indent.nonzero? ? '. ' : '> '
  prompt = prompt.green if @color
  if @reline
    Reline.pre_input_hook = -> do
      Reline.insert_text '  ' * indent
      Reline.redisplay
      Reline.pre_input_hook = nil
    end
    Reline.readline prompt, true
  else
    $stdout.print prompt
    $stdout.flush
    $stdin.gets chomp: true
  end
end

# File lib/alda-rb/repl.rb, line 339
def run
  start
  while code = rb_code
    next if code.empty?
    break unless process_rb_code code
  end
  terminate
end

# File lib/alda-rb/repl.rb, line 268
def setup_repl opts
  if Alda.v1?
    @history = StringIO.new
  else
    @port = (opts.fetch :port, -1).to_i
    @host = opts.fetch :host, 'localhost'
    unless @port.positive? && %w[localhost 127.0.0.1].include?(@host) &&
           Alda.processes.any? { _1[:port] == @port && _1[:type] == :repl_server }
      Alda.env(ALDA_DISABLE_SPAWNING: :no) { @nrepl_pipe = Alda.pipe :repl, **opts, server: true }
      /nrepl:\/\/[a-zA-Z0-9._\-]+:(?<port>\d+)/ =~ @nrepl_pipe.gets
      @port = port.to_i
      Process.detach @nrepl_pipe.pid
    end
    @socket = TCPSocket.new @host, @port
    @bencode_parser = BEncode::Parser.new @socket
  end
  nil
end

# File lib/alda-rb/repl.rb, line 353
def start
end

# File lib/alda-rb/repl.rb, line 468
def terminate
  if Alda.v1?
    clear_history
  else
    if @nrepl_pipe
      if Alda::Utils.win_platform?
        unless IO.popen(['taskkill', '/f', '/pid', @nrepl_pipe.pid.to_s], &:read).include? 'SUCCESS'
          Alda::Warning.warn 'failed to kill nREPL server; may become zombie process'
        end
      else
        Process.kill :INT, @nrepl_pipe.pid
      end
      @nrepl_pipe.close
    end
    @socket.close
  end
end

# File lib/alda-rb/repl.rb, line 437
def try_command
  begin
    yield
  rescue Alda.v1? ? Alda::CommandLineError : Alda::NREPLServerError => e
    puts @color ? e.message.red : e.message
  end
end