/* eslint-disable */
// Adds a fade-out animation to grid layers when they're removed from the map

(function () {
  var gridProto = L.GridLayer.prototype
  var onRemoveProto = gridProto.onRemove
  var onAddProto = gridProto.onAdd
  var fadeDuration = 200

  L.GridLayer.include({

    onAdd: function (map) {
      if (this._fadeOutTime) {
        var now = performance.now() || (+new Date())
        L.Util.cancelAnimFrame(this._fadeOutFrame)
        this._fadeOutTime = now + fadeDuration - this._fadeOutTime + now
        L.Util.requestAnimFrame(this._fadeIn, this)
      } else {
        onAddProto.call(this, map)
      }
    },

    onRemove: function (map) {
      if (this._fadeOutTime) {
        // We're removing this *again* quickly after removing and re-adding
        var now = performance.now() || (+new Date())

        this._fadeOutTime = now + fadeDuration - this._fadeOutTime + now
      }
      this._fadeOutTime = (performance.now() || (+new Date())) + fadeDuration * 2
      this._fadeOutMap = this._map

      L.Util.requestAnimFrame(this._fadeOut, this)
    },

    _fadeOut: function () {
      if (!this._fadeOutTime || !this._container) { return }

      var now = performance.now() || (+new Date())

      var opacity = Math.min((this._fadeOutTime - now) / fadeDuration, 1)
      // console.log('fadeout:', opacity);
      if (opacity < 0) {
        this._fadeOutTime = false

        onRemoveProto.call(this, this._fadeOutMap)

        return
      }

      L.DomUtil.setOpacity(this._container, opacity * this.options.opacity)

      this._fadeOutFrame = L.Util.requestAnimFrame(this._fadeOut, this)
    },

    // Only runs when the gridlayer is quickly re-added while it's being faded out
    _fadeIn: function _fadeIn () {
      if (!this._fadeOutTime || !this._container) { return }

      var now = performance.now() || (+new Date())

      var opacity = (now - this._fadeOutTime) / fadeDuration
      // console.log('fadein:', opacity);

      if (opacity > 1) {
        this._fadeOutTime = false
        return
      }

      L.DomUtil.setOpacity(this._container, opacity * this.options.opacity)

      L.Util.requestAnimFrame(this._fadeIn, this)
    }

  })
})()