angular.module('tutorials', [])
.directive('docTutorialNav', function(templateMerge) {
  var pages = [
    '',
    'step_00', 'step_01', 'step_02', 'step_03', 'step_04',
    'step_05', 'step_06', 'step_07', 'step_08', 'step_09',
    'step_10', 'step_11', 'step_12', 'the_end'
  ];
  return {
    compile: function(element, attrs) {
      var seq = 1 * attrs.docTutorialNav,
          props = {
            seq: seq,
            prev: pages[seq],
            next: pages[2 + seq],
            diffLo: seq ? (seq - 1): '0~1',
            diffHi: seq
          };
      element.addClass('btn-group');
      element.addClass('tutorial-nav');
      element.append(templateMerge(
        '
Reset the workspace to step ' + step + '.
' + '' + command + '
Refresh your browser or check the app out on Angular\'s server.