$(function() {
  var ENTER_KEY_CODE = 13;

  var clearOutput = function() {
    $('#output').html('');
  };

  var executeCommand = function(command) {
    $.ajax({
      data: {
        command: command
      },
      method: 'POST',
      url: $('#shell').data('url')
    }).done(handleResponse);
  };

  var handleKeyPress = function(event) {
    if (event.which === ENTER_KEY_CODE) {
      var command = $(this).val();
      if (command === 'clear') {
        clearOutput();
      } else {
        printCommand(command);
        executeCommand(command);
      }
      $(this).val('');
    }
  };

  var handleResponse = function(response) {
    if (response.status === 'ok') {
      printOutput(response);
    } else if (response.status === 'timeout') {
      printTimeout(response);
    }
  };

  var printCommand = function(command) {
    $('#output').append('<p><em>' + command + '</em></p>');
  };

  var printOutput = function(output) {
    var element = $('<p>');
    if (output.stderr) {
      element.addClass('text-warning');
      element.html(output.stderr);
    } else if (output.stdout) {
      element.addClass('text-success');
      element.html(output.stdout);
    } else {
      element.addClass('text-muted');
      element.html($('#output').data('message-no-output'));
    }
    $('#output').append(element);
  };

  var printTimeout = function(output) {
    var element = $.append('<p>');
    element.addClass('text-danger');
    element.html($('#shell').data('message-timeout'));
    $('#output').append(element);
  };

  if ($('#shell').isPresent()) {
    $('#command').focus();
    $('#command').on('keypress', handleKeyPress);
  }
});