@difizen/mana-core/es/browser.js

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

/**
 * Resolves after the next animation frame if no parameter is given,
 * or after the given number of animation frames.
 */
export function animationFrame() {
  var n = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : 1;
  return new Promise(function (resolve) {
    function frameFunc() {
      if (n <= 0) {
        resolve();
      } else {
        n -= 1;
        requestAnimationFrame(frameFunc);
      }
    }
    frameFunc();
  });
}

/**
 * Parse a magnitude value (e.g. width, height, left, top) from a CSS attribute value.
 * Returns the given default value (or undefined) if the value cannot be determined,
 * e.g. because it is a relative value like `50%` or `auto`.
 */

export function parseCssMagnitude(value, defaultValue) {
  if (value) {
    var parsed;
    if (value.endsWith('px')) {
      parsed = parseFloat(value.substring(0, value.length - 2));
    } else {
      parsed = parseFloat(value);
    }
    if (!Number.isNaN(parsed)) {
      return parsed;
    }
  }
  return defaultValue;
}

/**
 * Parse the number of milliseconds from a CSS time value.
 * Returns the given default value (or undefined) if the value cannot be determined.
 */

export function parseCssTime(time, defaultValue) {
  if (time) {
    var parsed;
    if (time.endsWith('ms')) {
      parsed = parseFloat(time.substring(0, time.length - 2));
    } else if (time.endsWith('s')) {
      parsed = parseFloat(time.substring(0, time.length - 1)) * 1000;
    } else {
      parsed = parseFloat(time);
    }
    if (!Number.isNaN(parsed)) {
      return parsed;
    }
  }
  return defaultValue;
}
function getMonacoEditorScroll(elem) {
  var linesContent = elem.querySelector('.lines-content');
  var viewLines = elem.querySelector('.view-lines');
  if (linesContent === null || viewLines === null) {
    return undefined;
  }
  var linesContentStyle = linesContent.style;
  var elemStyle = elem.style;
  var viewLinesStyle = viewLines.style;
  return {
    left: -parseCssMagnitude(linesContentStyle.left, 0),
    top: -parseCssMagnitude(linesContentStyle.top, 0),
    maxLeft: parseCssMagnitude(viewLinesStyle.width, 0) - parseCssMagnitude(elemStyle.width, 0),
    maxTop: parseCssMagnitude(viewLinesStyle.height, 0) - parseCssMagnitude(elemStyle.height, 0)
  };
}

/**
 * Prevent browser back/forward navigation of a mouse wheel event.
 */
export function preventNavigation(event) {
  var currentTarget = event.currentTarget,
    deltaX = event.deltaX,
    deltaY = event.deltaY;
  var absDeltaX = Math.abs(deltaX);
  var absDeltaY = Math.abs(deltaY);
  var elem = event.target;
  while (elem && elem !== currentTarget) {
    var scroll = void 0;
    if (elem.classList.contains('monaco-scrollable-element')) {
      scroll = getMonacoEditorScroll(elem);
    } else {
      scroll = {
        left: elem.scrollLeft,
        top: elem.scrollTop,
        maxLeft: elem.scrollWidth - elem.clientWidth,
        maxTop: elem.scrollHeight - elem.clientHeight
      };
    }
    if (scroll) {
      var scrollH = scroll.maxLeft > 0 && (deltaX < 0 && scroll.left > 0 || deltaX > 0 && scroll.left < scroll.maxLeft);
      var scrollV = scroll.maxTop > 0 && (deltaY < 0 && scroll.top > 0 || deltaY > 0 && scroll.top < scroll.maxTop);
      if (scrollH && scrollV || scrollH && absDeltaX > absDeltaY || scrollV && absDeltaY > absDeltaX) {
        // The event is consumed by the scrollable child element
        return;
      }
    }
    elem = elem.parentElement;
  }
  event.preventDefault();
  event.stopPropagation();
}