tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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orientation.js (2877B)

      1 /* This Source Code Form is subject to the terms of the Mozilla Public
      2 * License, v. 2.0. If a copy of the MPL was not distributed with this
      3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      4 
      5 "use strict";
      6 
      7 const {
      8  PORTRAIT_PRIMARY,
      9  LANDSCAPE_PRIMARY,
     10 } = require("resource://devtools/client/responsive/constants.js");
     11 
     12 /**
     13 * Helper that gets the screen orientation of the device displayed in the RDM viewport.
     14 * This function take in both a device and viewport object and an optional rotated angle.
     15 * If a rotated angle is passed, then we calculate what the orientation type of the device
     16 * would be in relation to its current orientation. Otherwise, return the current
     17 * orientation and angle.
     18 *
     19 * @param {object} device
     20 *        The device whose content is displayed in the viewport. Used to determine the
     21 *        primary orientation.
     22 * @param {object} viewport
     23 *        The viewport displaying device content. Used to determine the current
     24 *        orientation type of the device while in RDM.
     25 * @param {number | null} angleToRotateTo
     26 *        Optional. The rotated angle specifies the degree to which the device WILL be
     27 *        turned to. If undefined, then only return the current orientation and angle
     28 *        of the device.
     29 * @return {object} the orientation of the device.
     30 */
     31 function getOrientation(device, viewport, angleToRotateTo = null) {
     32  const { width: deviceWidth, height: deviceHeight } = device;
     33  const { width: viewportWidth, height: viewportHeight } = viewport;
     34 
     35  // Determine the primary orientation of the device screen.
     36  const primaryOrientation =
     37    deviceHeight >= deviceWidth ? PORTRAIT_PRIMARY : LANDSCAPE_PRIMARY;
     38 
     39  // Determine the current orientation of the device screen.
     40  const currentOrientation =
     41    viewportHeight >= viewportWidth ? PORTRAIT_PRIMARY : LANDSCAPE_PRIMARY;
     42 
     43  // Calculate the orientation angle of the device.
     44  let angle;
     45 
     46  if (typeof angleToRotateTo === "number") {
     47    angle = angleToRotateTo;
     48  } else if (currentOrientation !== primaryOrientation) {
     49    angle = 90;
     50  } else {
     51    angle = 0;
     52  }
     53 
     54  // Calculate the orientation type of the device.
     55  let orientationType = currentOrientation;
     56 
     57  // If the viewport orientation is different from the primary orientation and the angle
     58  // to rotate to is 0, then we are moving the device orientation back to its primary
     59  // orientation.
     60  if (currentOrientation !== primaryOrientation && angleToRotateTo === 0) {
     61    orientationType = primaryOrientation;
     62  } else if (angleToRotateTo === 90 || angleToRotateTo === 270) {
     63    if (currentOrientation.includes("portrait")) {
     64      orientationType = LANDSCAPE_PRIMARY;
     65    } else if (currentOrientation.includes("landscape")) {
     66      orientationType = PORTRAIT_PRIMARY;
     67    }
     68  }
     69 
     70  return {
     71    type: orientationType,
     72    angle,
     73  };
     74 }
     75 
     76 exports.getOrientation = getOrientation;