@checksub_team/peaks_timeline/src/components/segment-shape.js

JavaScript UI component for displaying audio waveforms

/**
 * @file
 *
 * Defines the {@link SegmentShape} class.
 *
 * @module segment-shape
 */

define([
  'konva',
  './segment-marker',
  '../utils'
], function(
  Konva,
  SegmentMarker,
  Utils) {
  'use strict';

  var SEGMENT_WIDTH = 10;
  var SEGMENT_CORNER_RADIUS = 10;
  var INDICATOR_RADIUS = 4; // px
  var INDICATORS_MARGIN_RIGHT = 4; // px
  var INDICATORS_MARGIN_TOP = 8; // px

  /**
   * Creates a waveform segment shape with optional start and end markers.
   *
   * @class
   * @alias SegmentShape
   *
   * @param {Segment} segment
   * @param {Peaks} peaks
   * @param {SegmentsGroup} group
   * @param {WaveformOverview|WaveformZoomView} view
   */

  function SegmentShape(segment, peaks, group, view) {
    this._segment       = segment;
    this._peaks         = peaks;
    this._group         = group;
    this._view          = view;
    // this._waveformShape = null;
    this._segmentsGroup = null;
    this._label         = null;
    this._startMarker   = null;
    this._endMarker     = null;
    this._shapeGroup    = null;
    this._rectangle     = null;
    this._indicators    = {};
    this._selected      = this._segment.selected;
    this._hovered       = false;

    var self = this;

    this._segmentWidth = this._view.timeToPixels(this._segment.endTime - this._segment.startTime);
    this._segmentHeight = this._peaks.options.segmentHeight;

    this._shapeGroup = new Konva.Group({
      x: this._view.timeToPixels(this._segment.startTime),
      y: 0,
      width: this._segmentWidth,
      height: this._segmentHeight,
      draggable: this._segment.editable,
      clipFunc: function(ctx) {
        self._drawRect(ctx);
      }
    });

    var width = this._view.timeToPixels(this._segment.endTime - this._segment.startTime);
    var fillColor = segment.color + Math.round(segment.opacity * 255).toString(16);

    this._rectangle = new Konva.Rect({
      width: width,
      height: this._segmentHeight,
      cornerRadius: this._cornerRadius(),
      stroke: segment.borderColor || segment.textColor + 'FF',
      strokeWidth: !Utils.isNullOrUndefined(segment.borderWidth) ?
        segment.borderWidth :
        2,
      fillPriority: segment.shouldShowWarning() ? 'linear-gradient' : 'color',
      fill: fillColor,
      fillLinearGradientColorStops: [
        0, fillColor,
        0.65, segment.warningColor
      ],
      fillLinearGradientStartPointX: Math.max(width - 20, width / 2),
      fillLinearGradientEndPointX: width
    });

    this._shapeGroup.add(this._rectangle);

    this._shapeGroup.dragBoundFunc(function() {
      return self._onShapeGroupDrag(this);
    });

    // Set up event handlers to show/hide the segment label text when the user
    // hovers the mouse over the segment.
    this._shapeGroup.on('mouseenter', this._onMouseEnter.bind(this));
    this._shapeGroup.on('mouseleave', this._onMouseLeave.bind(this));
    this._shapeGroup.on('click', this._onClick.bind(this));

    this._shapeGroup.on('dragstart', this._onSegmentDragStart.bind(this));
    this._shapeGroup.on('dragend', this._onSegmentDragEnd.bind(this));

    // Event handlers for markers
    this._onSegmentHandleDrag      = this._onSegmentHandleDrag.bind(this);
    this._onSegmentHandleDragStart = this._onSegmentHandleDragStart.bind(this);
    this._onSegmentHandleDragEnd   = this._onSegmentHandleDragEnd.bind(this);

    this._createLabel();

    this._createMarkers();

    this._indicatorsGroup = new Konva.Group();
    this._shapeGroup.add(this._indicatorsGroup);

    this.createIndicators();
    this._applyVisualState();
  }

  SegmentShape.prototype._onShapeGroupDrag = function(draggedElement) {
    return this._view._sourcesLayer.onSegmentDrag(draggedElement);
  };

  SegmentShape.prototype._cornerRadius = function() {
    return !Utils.isNullOrUndefined(this._segment.borderRadius) ?
      this._segment.borderRadius :
      SEGMENT_CORNER_RADIUS;
  };

  SegmentShape.prototype._createLabel = function() {
    this._label = this._peaks.options.createSegmentLabel({
      x:        this._view.timeToPixels(this._segment.startTime),
      y:        this._segmentY,
      width:    this._view.timeToPixels(this._segment.endTime - this._segment.startTime),
      height:   this._segmentHeight,
      segment:  this._segment,
      view:     this._view.getName(),
      group:    this._group,
      fontSize: 12
    });
  };

  SegmentShape.prototype._getFillColor = function() {
    var color = this._segment.color;

    if (this._selected) {
      color = this._segment.selectedColor;
    }
    else if (this._hovered) {
      color = this._segment.hoverColor;
    }

    return color + Math.round(this._segment.opacity * 255).toString(16);
  };

  SegmentShape.prototype._getStrokeColor = function() {
    if (this._selected) {
      return this._segment.selectedBorderColor;
    }

    return this._segment.borderColor || this._segment.textColor + 'FF';
  };

  SegmentShape.prototype._getLabelTextColor = function() {
    return this._selected ? this._segment.selectedTextColor : this._segment.textColor;
  };

  SegmentShape.prototype._getHandleTextColor = function() {
    return this._selected ?
      this._segment.selectedHandleTextColor :
      this._segment.handleTextColor;
  };

  SegmentShape.prototype._applyVisualState = function() {
    var fillColor = this._getFillColor();
    var handleTextColor = this._getHandleTextColor();

    this._rectangle.fill(fillColor);
    this._rectangle.stroke(this._getStrokeColor());
    this._rectangle.fillLinearGradientColorStops([
      0, fillColor,
      0.65, this._segment.warningColor
    ]);

    if (this._label && this._label.fill) {
      this._label.fill(this._getLabelTextColor());
    }

    if (this._startMarker) {
      this._startMarker.setTextColor(handleTextColor);
    }

    if (this._endMarker) {
      this._endMarker.setTextColor(handleTextColor);
    }
  };

  SegmentShape.prototype.update = function() {
    this._applyDisplayTimes(this._segment.startTime, this._segment.endTime);
  };

  SegmentShape.prototype.setSelected = function() {
    this._selected = this._segment.selected;
    this._applyVisualState();
  };

  SegmentShape.prototype._applyDisplayTimes = function(startTime, endTime) {
    var startPixel  = this._view.timeToPixels(startTime);
    var endPixel    = this._view.timeToPixels(endTime);
    var frameOffset = this._view.timeToPixels(this._view.getTimeOffset());

    this._shapeGroup.x(startPixel - frameOffset);

    this._segmentWidth = endPixel - startPixel;

    this._shapeGroup.width(this._segmentWidth);
    this._rectangle.width(this._segmentWidth);
    if (this._segment.shouldShowWarning()) {
      this._rectangle.fillPriority('linear-gradient');
      this._rectangle.fillLinearGradientStartPointX(
        Math.max(this._segmentWidth - 20, this._segmentWidth / 2)
      );
      this._rectangle.fillLinearGradientEndPointX(this._segmentWidth);
    }
    else {
      this._rectangle.fillPriority('color');
    }

    this._indicatorsGroup.x(this._segmentWidth);

    var newWidth = Math.floor(this._segmentWidth / 2);

    if (this._segmentWidth
      < this._startMarker.getHandleWidth() + this._endMarker.getHandleWidth()) {
      this._startMarker.setHandleWidth(newWidth);
      this._endMarker.setHandleWidth(newWidth);
    }
    else if (this._startMarker.getHandleWidth() < SEGMENT_WIDTH
      && newWidth > this._startMarker.getHandleWidth()) {
      this._startMarker.setHandleWidth(Math.min(newWidth, SEGMENT_WIDTH));
      this._endMarker.setHandleWidth(Math.min(newWidth, SEGMENT_WIDTH));
    }

    if (this._startMarker) {
      this._startMarker.setX(startPixel - frameOffset);
      this._startMarker.timeUpdated(startTime);
    }

    if (this._endMarker) {
      this._endMarker.setX(endPixel - this._endMarker.getHandleWidth() - frameOffset);
      this._endMarker.timeUpdated(endTime);
    }

    if (this._label) {
      this._label.setX(startPixel - frameOffset);
      this._label.setWidth(endPixel - startPixel);
    }
  };

  SegmentShape.prototype.getSegmentHeight = function() {
    return this._segmentHeight;
  };

  SegmentShape.prototype.getText = function() {
    return this._label;
  };

  SegmentShape.prototype.getSegment = function() {
    return this._segment;
  };

  SegmentShape.prototype.getSegmentsGroup = function() {
    return this._segmentsGroup;
  };

  SegmentShape.prototype.getStartMarker = function() {
    return this._startMarker;
  };

  SegmentShape.prototype.getEndMarker = function() {
    return this._endMarker;
  };

  SegmentShape.prototype.stopDrag = function() {
    this._shapeGroup.stopDrag();
  };

  SegmentShape.prototype.moveTo = function(group, segmentsGroup) {
    if (segmentsGroup) {
      this._segmentsGroup = segmentsGroup;
    }

    this._shapeGroup.moveTo(group);

    if (this._label) {
      this._label.moveTo(group);
    }

    if (this._startMarker) {
      this._startMarker.moveTo(group);
    }

    if (this._endMarker) {
      this._endMarker.moveTo(group);
    }
  };

  SegmentShape.prototype._createMarkers = function() {
    var editable = this._group.isEditingEnabled() && this._segment.editable;

    var startMarker = this._peaks.options.createSegmentMarker({
      peaks:              this._peaks,
      segment:            this._segment,
      draggable:          editable,
      startMarker:        true,
      group:              this._group,
      view:               this._view,
      showSegmentMarkers: this._peaks.options.showSegmentMarkers,
      segmentHeight:      this._segmentHeight,
      segmentWidth:       SEGMENT_WIDTH,
      y:                  this._segmentY
    });

    if (startMarker) {
      this._startMarker = new SegmentMarker({
        segment:      this._segment,
        segmentShape: this,
        draggable:    editable,
        startMarker:  true,
        marker:       startMarker,
        onDrag:       this._onSegmentHandleDrag,
        onDragStart:  this._onSegmentHandleDragStart,
        onDragEnd:    this._onSegmentHandleDragEnd,
        view:         this._view
      });
    }

    var endMarker = this._peaks.options.createSegmentMarker({
      peaks:              this._peaks,
      segment:            this._segment,
      draggable:          editable,
      startMarker:        false,
      group:              this._group,
      view:               this._view,
      showSegmentMarkers: this._peaks.options.showSegmentMarkers,
      segmentHeight:      this._segmentHeight,
      segmentWidth:       SEGMENT_WIDTH,
      y:                  this._segmentY
    });

    if (endMarker) {
      this._endMarker = new SegmentMarker({
        segment:      this._segment,
        segmentShape: this,
        draggable:    editable,
        startMarker:  false,
        marker:       endMarker,
        onDrag:       this._onSegmentHandleDrag,
        onDragStart:  this._onSegmentHandleDragStart,
        onDragEnd:    this._onSegmentHandleDragEnd,
        view:         this._view
      });
    }
  };

  SegmentShape.prototype.createIndicators = function() {
    var newIndicatorsColors = this._segment.indicators;
    var oldIndicators = this._indicators;
    var newIndicators = {};

    if (newIndicatorsColors) {
      newIndicatorsColors.forEach(function(indicatorColor) {
        var oldIndicator = oldIndicators[indicatorColor];

        if (oldIndicator) {
          newIndicators[indicatorColor] = oldIndicator;
          delete oldIndicators[indicatorColor];
        }
        else {
          newIndicators[indicatorColor] = null;
        }
      });

      for (var color in oldIndicators) {
        if (Utils.objectHasProperty(oldIndicators, color)) {
          oldIndicators[color].destroy();
        }
      }
    }

    this._indicators = Object.keys(newIndicators)
      .sort()
      .reverse()
      .reduce(function(objEntries, key) {
        objEntries[key] = newIndicators[key];
        return objEntries;
        }, {}
      );

    this._createIndicators();
  };

  SegmentShape.prototype._createIndicators = function() {
    var currentX = 0;
    var zIndex = 0;

    for (var color in this._indicators) {
      if (Utils.objectHasProperty(this._indicators, color)) {
        if (!this._indicators[color]) {
          this._indicators[color] = new Konva.Circle({
            radius: INDICATOR_RADIUS,
            fill: color,
            strokeEnabled: false
          });
          this._indicatorsGroup.add(this._indicators[color]);
        }

        this._indicators[color].x(currentX);
        this._indicators[color].zIndex(zIndex);
        currentX += INDICATOR_RADIUS;
        zIndex += 1;
      }
    }

    this._indicatorsGroup.offsetX(currentX + INDICATORS_MARGIN_RIGHT);
    this._indicatorsGroup.offsetY(-INDICATORS_MARGIN_TOP);
  };

  SegmentShape.prototype._onMouseEnter = function() {
    this._view.setCursor('pointer');

    this._view.setHoveredElement(this);
    this._hovered = true;
    this._applyVisualState();

    this._view.batchDrawSourcesLayer();

    this._peaks.emit('segments.mouseenter', this._segment);
  };

  SegmentShape.prototype._onMouseLeave = function() {
    this._view.setCursor('default');

    this._view.setHoveredElement(null);
    this._hovered = false;
    this._applyVisualState();

    this._view.batchDrawSourcesLayer();

    this._peaks.emit('segments.mouseleave', this._segment);
  };

  SegmentShape.prototype._onClick = function() {
    this._peaks.emit('segments.click', this._segment);
  };

  SegmentShape.prototype._onSegmentDragStart = function() {
    this._view.setCursor('grab');

    this._view._sourcesLayer.onSegmentDragStart(this);
  };

  SegmentShape.prototype._onSegmentDragEnd = function() {
    this._view.setCursor('pointer');

    this._view._sourcesLayer.onSegmentDragEnd(this);
  };

  /**
   * @param {SegmentMarker} segmentMarker
   */

  SegmentShape.prototype._onSegmentHandleDrag = function() {
    this._peaks.emit('segments.dragged');
  };

  /**
   * @param {SegmentMarker} segmentMarker
   */

  SegmentShape.prototype._onSegmentHandleDragStart = function(segmentMarker) {
    this._view._sourcesLayer.onSegmentHandleDragStart(segmentMarker);
  };

  /**
   * @param {SegmentMarker} segmentMarker
   */

  SegmentShape.prototype._onSegmentHandleDragEnd = function(segmentMarker) {
    this._view._sourcesLayer.onSegmentHandleDragEnd(segmentMarker);
  };

  SegmentShape.prototype.fitToView = function() {
    if (this._startMarker) {
      this._startMarker.fitToView();
    }

    if (this._endMarker) {
      this._endMarker.fitToView();
    }
  };

  SegmentShape.prototype.destroy = function() {
    this._shapeGroup.destroy();

    if (this._label) {
      this._label.destroy();
    }

    if (this._startMarker) {
      this._startMarker.destroy();
    }

    if (this._endMarker) {
      this._endMarker.destroy();
    }
  };

  SegmentShape.prototype._drawRect = function(ctx) {
    var cornerRadius = this._cornerRadius();

    ctx.beginPath();
    ctx.moveTo(cornerRadius + 1.5, 0);
    ctx.lineTo(this._segmentWidth - cornerRadius - 1.5, 0);
    ctx.quadraticCurveTo(this._segmentWidth, 0, this._segmentWidth, cornerRadius + 1.5);
    ctx.lineTo(this._segmentWidth, this._segmentHeight - cornerRadius - 1.5);
    ctx.quadraticCurveTo(
      this._segmentWidth,
      this._segmentHeight,
      this._segmentWidth - cornerRadius - 1.5,
      this._segmentHeight
    );
    ctx.lineTo(cornerRadius + 1.5, this._segmentHeight);
    ctx.quadraticCurveTo(
      0, this._segmentHeight, 0, this._segmentHeight - cornerRadius - 1.5
    );
    ctx.lineTo(0, cornerRadius + 1.5);
    ctx.quadraticCurveTo(0, 0, cornerRadius + 1.5, 0);
    ctx.closePath();
  };

  return SegmentShape;
});