var urlHash = require('./urlHash.js');
   insertPreview = require('./insertPreview.js');
function DefaultHtmlSequencerUi(_sequencer, options) {

  options = options || {};
  var addStepSel = options.addStepSel = options.addStepSel || '#addStep';
  var removeStepSel = options.removeStepSel = options.removeStepSel || 'button.remove';
  var selectStepSel = options.selectStepSel = options.selectStepSel || '#selectStep';

  function onLoad() {
    importStepsFromUrlHash();
    if ($('#selectStep').val() === 'none')
      $(addStepSel + ' #add-step-btn').prop('disabled', true);
    handleSaveSequence();
  }

  // look up needed steps from Url Hash:
  function importStepsFromUrlHash() {
    var hash = urlHash.getUrlHashParameter('steps');

    if (hash) {
      _sequencer.importString(hash);
      _sequencer.run({ index: 0 });
    }
    urlHash.setUrlHashParameter('steps', sequencer.toString());
  }

  function selectNewStepUi() {
    var m = $(addStepSel + ' select').val();
    if(!m) m = arguments[0];
    else $(addStepSel + ' .info').html(_sequencer.modulesInfo(m).description);
    $(addStepSel + ' #add-step-btn').prop('disabled', false);
  }

  function removeStepUi() {
    var index = $(removeStepSel).index(this) + 1;
    // If last step is removed.
    if(sequencer.steps.length==index+1){
      console.log("inside")
      insertPreview.updatePreviews(sequencer.steps[index-1].output.src, document.querySelector('#addStep'));
    }
    sequencer.removeSteps(index).run({ index: index - 1 });
    // remove from URL hash too
    urlHash.setUrlHashParameter('steps', sequencer.toString());
    //disable save-sequence button if all steps are removed
    handleSaveSequence();
  }

  function addStepUi() {
    if ($(addStepSel + ' select').val() == 'none') return;
    var newStepName;
    if(typeof arguments[0] !== 'string')
      newStepName = $(addStepSel + ' select option').html().toLowerCase().split(' ').join('-');
    else newStepName = arguments[0];

    
    /*
    * after adding the step we run the sequencer from defined step
    * and since loadImage is not a part of the drawarray the step lies at current
    * length - 2 of the drawarray
    */
    var sequenceLength = 1;
    if (sequencer.sequences[newStepName]) {
      sequenceLength = sequencer.sequences[newStepName].length;
    } else if (sequencer.modules[newStepName][1]['length']) {
      sequenceLength = sequencer.modules[newStepName][1]['length'];
    }
    _sequencer
      .addSteps(newStepName, options)
      .run({ index: _sequencer.steps.length - sequenceLength - 1 });
    $(addStepSel + ' .info').html('Select a new module to add to your sequence.');
    $(addStepSel + ' select').val('none');

    //enable save-sequence button if disabled initially
    handleSaveSequence();

    // add to URL hash too
    urlHash.setUrlHashParameter('steps', _sequencer.toString());
  }

  function handleSaveSequence(){
    var stepCount = sequencer.steps.length;
    if(stepCount < 2)
      $(' #save-seq').prop('disabled', true);
    else
      $(' #save-seq').prop('disabled', false);
  }

  return {
    onLoad: onLoad,
    importStepsFromUrlHash: importStepsFromUrlHash,
    selectNewStepUi: selectNewStepUi,
    removeStepUi: removeStepUi,
    addStepUi: addStepUi
  };
}

module.exports = DefaultHtmlSequencerUi;