(function () {
  var ns = $.namespace('pskl.controller');

  var ACTION = {
    SELECT : 'select',
    CLONE : 'clone',
    DELETE : 'delete',
    NEW_FRAME : 'newframe'
  };

  ns.FramesListController = function (piskelController, container) {
    this.piskelController = piskelController;
    this.container = container;
    this.refreshZoom_();

    this.redrawFlag = true;

    this.cachedFrameProcessor = new pskl.model.frame.CachedFrameProcessor();
    this.cachedFrameProcessor.setFrameProcessor(this.frameToPreviewCanvas_.bind(this));
    this.cachedFrameProcessor.setOutputCloner(this.clonePreviewCanvas_.bind(this));
  };

  ns.FramesListController.prototype.init = function() {
    $.subscribe(Events.TOOL_RELEASED, this.flagForRedraw_.bind(this));
    $.subscribe(Events.PISKEL_RESET, this.flagForRedraw_.bind(this));
    $.subscribe(Events.USER_SETTINGS_CHANGED, this.flagForRedraw_.bind(this));

    $.subscribe(Events.PISKEL_RESET, this.refreshZoom_.bind(this));

    $('#preview-list-scroller').scroll(this.updateScrollerOverflows.bind(this));
    this.container.get(0).addEventListener('click', this.onContainerClick_.bind(this));
    this.updateScrollerOverflows();
  };

  ns.FramesListController.prototype.flagForRedraw_ = function () {
    this.redrawFlag = true;
  };

  ns.FramesListController.prototype.refreshZoom_ = function () {
    this.zoom = this.calculateZoom_();
  };

  ns.FramesListController.prototype.render = function () {
    if (this.redrawFlag) {
      this.createPreviews_();
      this.redrawFlag = false;
    }
  };

  ns.FramesListController.prototype.updateScrollerOverflows = function () {
    var scroller = $('#preview-list-scroller');
    var scrollerHeight = scroller.height();
    var scrollTop = scroller.scrollTop();
    var scrollerContentHeight = $('#preview-list').height();
    var treshold = $('.top-overflow').height();
    var overflowTop = false;
    var overflowBottom = false;

    if (scrollerHeight < scrollerContentHeight) {
      if (scrollTop > treshold) {
        overflowTop = true;
      }
      var scrollBottom = (scrollerContentHeight - scrollTop) - scrollerHeight;
      if (scrollBottom > treshold) {
        overflowBottom = true;
      }
    }
    var wrapper = $('#preview-list-wrapper');
    wrapper.toggleClass('top-overflow-visible', overflowTop);
    wrapper.toggleClass('bottom-overflow-visible', overflowBottom);
  };

  ns.FramesListController.prototype.onContainerClick_ = function (event) {
    var target = pskl.utils.Dom.getParentWithData(event.target, 'tileAction');
    if (!target) {
      return;
    }
    var action = target.dataset.tileAction;
    var index = parseInt(target.dataset.tileNumber, 10);

    if (action === ACTION.CLONE) {
      this.piskelController.duplicateFrameAt(index);
      this.updateScrollerOverflows();
    } else if (action === ACTION.DELETE) {
      this.piskelController.removeFrameAt(index);
      this.updateScrollerOverflows();
    } else if (action === ACTION.SELECT) {
      this.piskelController.setCurrentFrameIndex(index);
    } else if (action === ACTION.NEW_FRAME) {
      this.piskelController.addFrame();
      this.updateScrollerOverflows();
    }
  };

  ns.FramesListController.prototype.createPreviews_ = function () {
    this.container.html('');
    // Manually remove tooltips since mouseout events were shortcut by the DOM refresh:
    $('.tooltip').remove();

    var frameCount = this.piskelController.getFrameCount();

    for (var i = 0 ; i < frameCount ; i++) {
      this.container.append(this.createPreviewTile_(i));
    }
    // Append 'new empty frame' button
    var newFrameButton = document.createElement('div');
    newFrameButton.id = 'add-frame-action';
    newFrameButton.className = 'add-frame-action';
    newFrameButton.setAttribute('data-tile-action', ACTION.NEW_FRAME);
    newFrameButton.innerHTML = '<p class="label">Add new frame</p>';
    this.container.append(newFrameButton);

    var needDragndropBehavior = (frameCount > 1);
    if (needDragndropBehavior) {
      this.initDragndropBehavior_();
    }
    this.updateScrollerOverflows();
  };

  /**
   * @private
   */
  ns.FramesListController.prototype.initDragndropBehavior_ = function () {

    $('#preview-list').sortable({
      placeholder: 'preview-tile-drop-proxy',
      update: $.proxy(this.onUpdate_, this),
      items: '.preview-tile'
    });
    $('#preview-list').disableSelection();
  };

  /**
   * @private
   */
  ns.FramesListController.prototype.onUpdate_ = function (event, ui) {
    var originFrameId = parseInt(ui.item.data('tile-number'), 10);
    var targetInsertionId = $('.preview-tile').index(ui.item);

    this.piskelController.moveFrame(originFrameId, targetInsertionId);
    this.piskelController.setCurrentFrameIndex(targetInsertionId);
  };

  /**
   * @private
   * TODO(vincz): clean this giant rendering function & remove listeners.
   */
  ns.FramesListController.prototype.createPreviewTile_ = function(tileNumber) {
    var currentFrame = this.piskelController.getCurrentLayer().getFrameAt(tileNumber);

    var previewTileRoot = document.createElement('li');
    previewTileRoot.setAttribute('data-tile-number', tileNumber);
    previewTileRoot.setAttribute('data-tile-action', ACTION.SELECT);
    previewTileRoot.classList.add('preview-tile');
    if (this.piskelController.getCurrentFrame() == currentFrame) {
      previewTileRoot.classList.add('selected');
    }

    var canvasContainer = document.createElement('div');
    canvasContainer.classList.add('canvas-container', pskl.UserSettings.get(pskl.UserSettings.CANVAS_BACKGROUND));

    var height = this.zoom * this.piskelController.getCurrentFrame().getHeight();
    var horizontalMargin = (Constants.PREVIEW_FILM_SIZE - height) / 2;
    canvasContainer.style.marginTop = horizontalMargin + 'px';

    var width = this.zoom * this.piskelController.getCurrentFrame().getWidth();
    var verticalMargin = (Constants.PREVIEW_FILM_SIZE - width) / 2;
    canvasContainer.style.marginLeft = verticalMargin + 'px';
    canvasContainer.style.marginRight = verticalMargin + 'px';

    var canvasBackground = document.createElement('div');
    canvasBackground.className = 'canvas-background';
    canvasContainer.appendChild(canvasBackground);

    var cloneFrameButton = document.createElement('button');
    cloneFrameButton.setAttribute('rel', 'tooltip');
    cloneFrameButton.setAttribute('data-placement', 'right');
    cloneFrameButton.setAttribute('data-tile-number', tileNumber);
    cloneFrameButton.setAttribute('data-tile-action', ACTION.CLONE);
    cloneFrameButton.setAttribute('title', 'Duplicate this frame');
    cloneFrameButton.className = 'tile-overlay duplicate-frame-action';
    previewTileRoot.appendChild(cloneFrameButton);

    canvasContainer.appendChild(this.getCanvasForFrame(currentFrame));
    previewTileRoot.appendChild(canvasContainer);

    if (tileNumber > 0 || this.piskelController.getFrameCount() > 1) {
      // Add 'remove frame' button.
      var deleteButton = document.createElement('button');
      deleteButton.setAttribute('rel', 'tooltip');
      deleteButton.setAttribute('data-placement', 'right');
      deleteButton.setAttribute('title', 'Delete this frame');
      deleteButton.setAttribute('data-tile-number', tileNumber);
      deleteButton.setAttribute('data-tile-action', ACTION.DELETE);
      deleteButton.className = 'tile-overlay delete-frame-action';
      previewTileRoot.appendChild(deleteButton);

      // Add 'dragndrop handle'.
      var dndHandle = document.createElement('div');
      dndHandle.className = 'tile-overlay dnd-action';
      previewTileRoot.appendChild(dndHandle);
    }
    var tileCount = document.createElement('div');
    tileCount.className = 'tile-overlay tile-count';
    tileCount.innerHTML = tileNumber + 1;
    previewTileRoot.appendChild(tileCount);

    return previewTileRoot;
  };

  ns.FramesListController.prototype.getCanvasForFrame = function (frame) {
    var canvas = this.cachedFrameProcessor.get(frame, this.zoom);
    return canvas;
  };

  ns.FramesListController.prototype.frameToPreviewCanvas_ = function (frame) {
    var canvasRenderer = new pskl.rendering.CanvasRenderer(frame, this.zoom);
    canvasRenderer.drawTransparentAs(Constants.TRANSPARENT_COLOR);
    var canvas = canvasRenderer.render();
    canvas.classList.add('tile-view', 'canvas');
    return canvas;
  };

  ns.FramesListController.prototype.clonePreviewCanvas_ = function (canvas) {
    var clone = pskl.utils.CanvasUtils.clone(canvas);
    clone.classList.add('tile-view', 'canvas');
    return clone;
  };

  /**
   * Calculate the preview zoom depending on the piskel size
   */
  ns.FramesListController.prototype.calculateZoom_ = function () {
    var frame = this.piskelController.getCurrentFrame();
    var frameSize = Math.max(frame.getHeight(), frame.getWidth());

    return Constants.PREVIEW_FILM_SIZE / frameSize;
  };
})();