DevTools: extract modules (non-extensions)

third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-/**
- * @unrestricted
- */
-UI.ChartViewport = class extends UI.VBox {
-  constructor() {
-    super(true);
-
-    this.viewportElement = this.contentElement.createChild('div', 'fill');
-    this.viewportElement.addEventListener('mousewheel', this._onMouseWheel.bind(this), false);
-    this.viewportElement.addEventListener('keydown', this._handleZoomPanKeys.bind(this), false);
-
-    UI.installInertialDragHandle(
-        this.viewportElement, this._startDragging.bind(this), this._dragging.bind(this), this._endDragging.bind(this),
-        '-webkit-grabbing', null);
-    UI.installDragHandle(
-        this.viewportElement, this._startRangeSelection.bind(this), this._rangeSelectionDragging.bind(this),
-        this._endRangeSelection.bind(this), 'text', null);
-
-    this._alwaysShowVerticalScroll = false;
-    this._vScrollElement = this.contentElement.createChild('div', 'flame-chart-v-scroll');
-    this._vScrollContent = this._vScrollElement.createChild('div');
-    this._vScrollElement.addEventListener('scroll', this._onScroll.bind(this), false);
-
-    this._selectionOverlay = this.contentElement.createChild('div', 'flame-chart-selection-overlay hidden');
-    this._selectedTimeSpanLabel = this._selectionOverlay.createChild('div', 'time-span');
-
-    this.reset();
-  }
-
-  alwaysShowVerticalScroll() {
-    this._alwaysShowVerticalScroll = true;
-    this._vScrollElement.classList.add('always-show-scrollbar');
-  }
-
-  /**
-   * @return {boolean}
-   */
-  isDragging() {
-    return this._isDragging;
-  }
-
-  /**
-   * @override
-   * @return {!Array<!Element>}
-   */
-  elementsToRestoreScrollPositionsFor() {
-    return [this._vScrollElement];
-  }
-
-  /**
-   * @private
-   */
-  _updateScrollBar() {
-    const showScroll = this._alwaysShowVerticalScroll || this._totalHeight > this._offsetHeight;
-    if (this._vScrollElement.classList.contains('hidden') !== showScroll)
-      return;
-    this._vScrollElement.classList.toggle('hidden', !showScroll);
-    this._updateContentElementSize();
-  }
-
-  /**
-   * @override
-   */
-  onResize() {
-    this._updateScrollBar();
-    this._updateContentElementSize();
-    this.scheduleUpdate();
-  }
-
-  reset() {
-    this._vScrollElement.scrollTop = 0;
-    this._scrollTop = 0;
-    this._rangeSelectionStart = 0;
-    this._rangeSelectionEnd = 0;
-    this._isDragging = false;
-    this._dragStartPointX = 0;
-    this._dragStartPointY = 0;
-    this._dragStartScrollTop = 0;
-    this._timeWindowLeft = 0;
-    this._timeWindowRight = 0;
-    this._offsetWidth = 0;
-    this._offsetHeight = 0;
-    this._totalHeight = 0;
-    this._pendingAnimationTimeLeft = 0;
-    this._pendingAnimationTimeRight = 0;
-  }
-
-  /**
-   * @private
-   */
-  _updateContentElementSize() {
-    var offsetWidth = this._vScrollElement.offsetLeft;
-    if (!offsetWidth)
-      offsetWidth = this.contentElement.offsetWidth;
-    this._offsetWidth = offsetWidth;
-    this._offsetHeight = this.contentElement.offsetHeight;
-  }
-
-  setContentHeight(totalHeight) {
-    this._totalHeight = totalHeight;
-    this._vScrollContent.style.height = totalHeight + 'px';
-    this._updateScrollBar();
-    if (this._scrollTop + this._offsetHeight <= totalHeight)
-      return;
-    this._scrollTop = Math.max(0, totalHeight - this._offsetHeight);
-    this._vScrollElement.scrollTop = this._scrollTop;
-  }
-
-  /**
-   * @param {number} offset
-   * @param {number=} height
-   */
-  setScrollOffset(offset, height) {
-    height = height || 0;
-    if (this._vScrollElement.scrollTop > offset)
-      this._vScrollElement.scrollTop = offset;
-    else if (this._vScrollElement.scrollTop < offset - this._offsetHeight + height)
-      this._vScrollElement.scrollTop = offset - this._offsetHeight + height;
-  }
-
-  /**
-   * @return {number}
-   */
-  getScrollOffset() {
-    return this._vScrollElement.scrollTop;
-  }
-
-  /**
-   * @param {!Event} e
-   * @private
-   */
-  _onMouseWheel(e) {
-    if (!this._enabled())
-      return;
-    // Pan vertically when shift down only.
-    var panVertically = e.shiftKey && (e.wheelDeltaY || Math.abs(e.wheelDeltaX) === 120);
-    var panHorizontally = Math.abs(e.wheelDeltaX) > Math.abs(e.wheelDeltaY) && !e.shiftKey;
-    if (panVertically) {
-      this._vScrollElement.scrollTop -= (e.wheelDeltaY || e.wheelDeltaX) / 120 * this._offsetHeight / 8;
-    } else if (panHorizontally) {
-      var shift = -e.wheelDeltaX * this._pixelToTime;
-      this._muteAnimation = true;
-      this._handlePanGesture(shift);
-      this._muteAnimation = false;
-    } else {  // Zoom.
-      const mouseWheelZoomSpeed = 1 / 120;
-      this._handleZoomGesture(Math.pow(1.2, -(e.wheelDeltaY || e.wheelDeltaX) * mouseWheelZoomSpeed) - 1);
-    }
-
-    // Block swipe gesture.
-    e.consume(true);
-  }
-
-  /**
-   * @param {number} x
-   * @param {number} y
-   * @param {!MouseEvent} event
-   * @private
-   * @return {boolean}
-   */
-  _startDragging(x, y, event) {
-    if (event.shiftKey)
-      return false;
-    if (this._windowRight === Infinity)
-      return false;
-    this._isDragging = true;
-    this._initMaxDragOffset(event);
-    this._dragStartPointX = x;
-    this._dragStartPointY = y;
-    this._dragStartScrollTop = this._vScrollElement.scrollTop;
-    this.viewportElement.style.cursor = '';
-    this.hideHighlight();
-    return true;
-  }
-
-  /**
-   * @param {number} x
-   * @param {number} y
-   * @private
-   */
-  _dragging(x, y) {
-    var pixelShift = this._dragStartPointX - x;
-    this._dragStartPointX = x;
-    this._muteAnimation = true;
-    this._handlePanGesture(pixelShift * this._pixelToTime);
-    this._muteAnimation = false;
-
-    var pixelScroll = this._dragStartPointY - y;
-    this._vScrollElement.scrollTop = this._dragStartScrollTop + pixelScroll;
-    this._updateMaxDragOffset(x, y);
-  }
-
-  /**
-   * @private
-   */
-  _endDragging() {
-    this._isDragging = false;
-    this._updateHighlight();
-  }
-
-  /**
-   * @param {!MouseEvent} event
-   * @private
-   */
-  _initMaxDragOffset(event) {
-    this._maxDragOffsetSquared = 0;
-    this._dragStartX = event.pageX;
-    this._dragStartY = event.pageY;
-  }
-
-  /**
-   * @param {number} x
-   * @param {number} y
-   * @private
-   */
-  _updateMaxDragOffset(x, y) {
-    var dx = x - this._dragStartX;
-    var dy = y - this._dragStartY;
-    var dragOffsetSquared = dx * dx + dy * dy;
-    this._maxDragOffsetSquared = Math.max(this._maxDragOffsetSquared, dragOffsetSquared);
-  }
-
-  /**
-   * @return {number}
-   */
-  maxDragOffset() {
-    return Math.sqrt(this._maxDragOffsetSquared);
-  }
-
-  /**
-   * @param {!MouseEvent} event
-   * @private
-   * @return {boolean}
-   */
-  _startRangeSelection(event) {
-    if (!event.shiftKey)
-      return false;
-    this._isDragging = true;
-    this._initMaxDragOffset(event);
-    this._selectionOffsetShiftX = event.offsetX - event.pageX;
-    this._selectionOffsetShiftY = event.offsetY - event.pageY;
-    this._selectionStartX = event.offsetX;
-    var style = this._selectionOverlay.style;
-    style.left = this._selectionStartX + 'px';
-    style.width = '1px';
-    this._selectedTimeSpanLabel.textContent = '';
-    this._selectionOverlay.classList.remove('hidden');
-    this.hideHighlight();
-    return true;
-  }
-
-  /**
-   * @private
-   */
-  _endRangeSelection() {
-    this._isDragging = false;
-    this._updateHighlight();
-  }
-
-  hideRangeSelection() {
-    this._selectionOverlay.classList.add('hidden');
-  }
-
-  /**
-   * @param {!MouseEvent} event
-   * @private
-   */
-  _rangeSelectionDragging(event) {
-    this._updateMaxDragOffset(event.pageX, event.pageY);
-    var x = Number.constrain(event.pageX + this._selectionOffsetShiftX, 0, this._offsetWidth);
-    var start = this._cursorTime(this._selectionStartX);
-    var end = this._cursorTime(x);
-    this._rangeSelectionStart = Math.min(start, end);
-    this._rangeSelectionEnd = Math.max(start, end);
-    this._updateRangeSelectionOverlay();
-    this._flameChartDelegate.updateRangeSelection(this._rangeSelectionStart, this._rangeSelectionEnd);
-  }
-
-  /**
-   * @private
-   */
-  _updateRangeSelectionOverlay() {
-    var /** @const */ margin = 100;
-    var left = Number.constrain(this._timeToPosition(this._rangeSelectionStart), -margin, this._offsetWidth + margin);
-    var right = Number.constrain(this._timeToPosition(this._rangeSelectionEnd), -margin, this._offsetWidth + margin);
-    var style = this._selectionOverlay.style;
-    style.left = left + 'px';
-    style.width = (right - left) + 'px';
-    var timeSpan = this._rangeSelectionEnd - this._rangeSelectionStart;
-    this._selectedTimeSpanLabel.textContent = Number.preciseMillisToString(timeSpan, 2);
-  }
-
-  /**
-   * @private
-   */
-  _onScroll() {
-    this._scrollTop = this._vScrollElement.scrollTop;
-    this.scheduleUpdate();
-  }
-
-  /**
-   * @param {!Event} e
-   * @private
-   */
-  _handleZoomPanKeys(e) {
-    if (!UI.KeyboardShortcut.hasNoModifiers(e))
-      return;
-    var zoomMultiplier = e.shiftKey ? 0.8 : 0.3;
-    var panMultiplier = e.shiftKey ? 320 : 80;
-    if (e.code === 'KeyA') {
-      this._handlePanGesture(-panMultiplier * this._pixelToTime);
-      e.consume(true);
-    } else if (e.code === 'KeyD') {
-      this._handlePanGesture(panMultiplier * this._pixelToTime);
-      e.consume(true);
-    } else if (e.code === 'KeyW') {
-      this._handleZoomGesture(-zoomMultiplier);
-      e.consume(true);
-    } else if (e.code === 'KeyS') {
-      this._handleZoomGesture(zoomMultiplier);
-      e.consume(true);
-    }
-  }
-
-  /**
-   * @param {number} zoom
-   * @private
-   */
-  _handleZoomGesture(zoom) {
-    this._cancelAnimation();
-    var bounds = this._windowForGesture();
-    var cursorTime = this._cursorTime(this._lastMouseOffsetX);
-    bounds.left += (bounds.left - cursorTime) * zoom;
-    bounds.right += (bounds.right - cursorTime) * zoom;
-    this._requestWindowTimes(bounds);
-  }
-
-  /**
-   * @param {number} shift
-   * @private
-   */
-  _handlePanGesture(shift) {
-    this._cancelAnimation();
-    var bounds = this._windowForGesture();
-    shift = Number.constrain(
-        shift, this._minimumBoundary - bounds.left, this._totalTime + this._minimumBoundary - bounds.right);
-    bounds.left += shift;
-    bounds.right += shift;
-    this._requestWindowTimes(bounds);
-  }
-
-  /**
-   * @private
-   * @return {{left: number, right: number}}
-   */
-  _windowForGesture() {
-    var windowLeft = this._timeWindowLeft ? this._timeWindowLeft : this._dataProvider.minimumBoundary();
-    var windowRight = this._timeWindowRight !== Infinity ?
-        this._timeWindowRight :
-        this._dataProvider.minimumBoundary() + this._dataProvider.totalTime();
-    return {left: windowLeft, right: windowRight};
-  }
-
-  /**
-   * @param {{left: number, right: number}} bounds
-   * @private
-   */
-  _requestWindowTimes(bounds) {
-    bounds.left = Number.constrain(bounds.left, this._minimumBoundary, this._totalTime + this._minimumBoundary);
-    bounds.right = Number.constrain(bounds.right, this._minimumBoundary, this._totalTime + this._minimumBoundary);
-    if (bounds.right - bounds.left < UI.FlameChart.MinimalTimeWindowMs)
-      return;
-    this._flameChartDelegate.requestWindowTimes(bounds.left, bounds.right);
-  }
-
-  /**
-   * @param {number} startTime
-   * @param {number} endTime
-   * @private
-   */
-  _animateWindowTimes(startTime, endTime) {
-    this._timeWindowLeft = startTime;
-    this._timeWindowRight = endTime;
-    this._updateHighlight();
-    this.update();
-  }
-
-  /**
-   * @private
-   */
-  _animationCompleted() {
-    delete this._cancelWindowTimesAnimation;
-    this._updateHighlight();
-  }
-
-  /**
-   * @private
-   */
-  _cancelAnimation() {
-    if (!this._cancelWindowTimesAnimation)
-      return;
-    this._timeWindowLeft = this._pendingAnimationTimeLeft;
-    this._timeWindowRight = this._pendingAnimationTimeRight;
-    this._cancelWindowTimesAnimation();
-    delete this._cancelWindowTimesAnimation;
-  }
-
-  scheduleUpdate() {
-    if (this._updateTimerId || this._cancelWindowTimesAnimation)
-      return;
-    this._updateTimerId = this.element.window().requestAnimationFrame(() => {
-      this._updateTimerId = 0;
-      this.update();
-    });
-  }
-
-  update() {
-  }
-
-  /**
-   * @param {number} startTime
-   * @param {number} endTime
-   */
-  setWindowTimes(startTime, endTime) {
-    this.hideRangeSelection();
-    if (this._muteAnimation || this._timeWindowLeft === 0 || this._timeWindowRight === Infinity ||
-        (startTime === 0 && endTime === Infinity) || (startTime === Infinity && endTime === Infinity)) {
-      // Initial setup.
-      this._timeWindowLeft = startTime;
-      this._timeWindowRight = endTime;
-      this.scheduleUpdate();
-      return;
-    }
-    this._cancelAnimation();
-    this._cancelWindowTimesAnimation = UI.animateFunction(
-        this.element.window(), this._animateWindowTimes.bind(this),
-        [{from: this._timeWindowLeft, to: startTime}, {from: this._timeWindowRight, to: endTime}], 5,
-        this._animationCompleted.bind(this));
-    this._pendingAnimationTimeLeft = startTime;
-    this._pendingAnimationTimeRight = endTime;
-  }
-};