expo-screen-orientation/src/ExpoScreenOrientation.web.ts

Expo universal module for managing device's screen orientation

import { NativeModule, Platform, registerWebModule } from 'expo-modules-core';

import { getOrientationLockAsync, getOrientationAsync } from './ScreenOrientation';
import {
  Orientation,
  OrientationLock,
  WebOrientationLock,
  WebOrientation,
  ExpoOrientationEvents,
} from './ScreenOrientation.types';

const OrientationLockAPIToWeb: {
  [lock: string]: WebOrientationLock;
} = {
  [OrientationLock.DEFAULT]: WebOrientationLock.NATURAL,
  [OrientationLock.ALL]: WebOrientationLock.ANY,
  [OrientationLock.PORTRAIT]: WebOrientationLock.PORTRAIT,
  [OrientationLock.PORTRAIT_UP]: WebOrientationLock.PORTRAIT_PRIMARY,
  [OrientationLock.PORTRAIT_DOWN]: WebOrientationLock.PORTRAIT_SECONDARY,
  [OrientationLock.LANDSCAPE]: WebOrientationLock.LANDSCAPE,
  [OrientationLock.LANDSCAPE_LEFT]: WebOrientationLock.LANDSCAPE_PRIMARY,
  [OrientationLock.LANDSCAPE_RIGHT]: WebOrientationLock.LANDSCAPE_SECONDARY,
};

const OrientationWebToAPI: {
  [orientationWeb: string]: Orientation;
} = {
  [WebOrientation.PORTRAIT_PRIMARY]: Orientation.PORTRAIT_UP,
  [WebOrientation.PORTRAIT_SECONDARY]: Orientation.PORTRAIT_DOWN,
  [WebOrientation.LANDSCAPE_PRIMARY]: Orientation.LANDSCAPE_LEFT,
  [WebOrientation.LANDSCAPE_SECONDARY]: Orientation.LANDSCAPE_RIGHT,
};

declare const window: Window;

const screen: Screen = Platform.canUseViewport ? window.screen : ({} as Screen);

function _convertToLegacyOrientationLock(orientationLock: WebOrientationLock): string | string[] {
  switch (orientationLock) {
    case WebOrientationLock.UNKNOWN:
      throw new Error(
        `expo-screen-orientation: WebOrientationLock.UNKNOWN is not a valid lock to be converted.`
      );
    case WebOrientationLock.ANY:
      return ['portrait', 'landscape'];
    case WebOrientationLock.NATURAL:
      return 'default';
    default:
      return orientationLock;
  }
}

async function _lockAsync(webOrientationLock: WebOrientationLock): Promise<void> {
  if (webOrientationLock === WebOrientationLock.UNKNOWN) {
    throw new Error(
      `expo-screen-orientation: WebOrientationLock.UNKNOWN is not a valid lock that can be applied to the device.`
    );
  }
  // @ts-ignore-error: This is missing in the TypeScript definitions
  if (screen.orientation && screen.orientation.lock) {
    // @ts-ignore-error
    await screen.orientation.lock(webOrientationLock);
  } else if (
    screen['lockOrientation'] ||
    screen['mozLockOrientation'] ||
    screen['msLockOrientation']
  ) {
    const legacyLock = _convertToLegacyOrientationLock(webOrientationLock);
    const lockOrientation =
      screen['lockOrientation'] || screen['mozLockOrientation'] || screen['msLockOrientation'];
    // correct `this` context must be passed in otherwise method call is disallowed by browser
    const isSuccess = lockOrientation.call(screen, legacyLock);
    if (!isSuccess) {
      throw new Error(
        `Applying orientation lock: ${JSON.stringify(webOrientationLock)} to device was denied`
      );
    }
  } else {
    throw new Error(
      `expo-screen-orientation: The browser doesn't support locking screen orientation.`
    );
  }
}

let _lastWebOrientationLock: WebOrientationLock = WebOrientationLock.UNKNOWN;

class ExpoScreenOrientation extends NativeModule<ExpoOrientationEvents> {
  orientation: ScreenOrientation | null = Platform.canUseViewport
    ? screen.orientation || (screen as any).msOrientation || null
    : null;
  async emitOrientationEvent() {
    const [orientationLock, orientation] = await Promise.all([
      getOrientationLockAsync(),
      getOrientationAsync(),
    ]);
    this.emit('expoDidUpdateDimensions', {
      orientationLock,
      orientationInfo: { orientation },
    });
  }
  startObserving() {
    this.listener = () => this.emitOrientationEvent();
    if (Platform.canUseEventListeners) {
      if (this.orientation && this.orientation.addEventListener) {
        this.orientation.addEventListener('change', this.listener);
      } else {
        window.addEventListener('orientationchange', this.listener);
      }
    }
  }
  stopObserving(): void {
    if (Platform.canUseEventListeners) {
      if (this.orientation && this.orientation.removeEventListener) {
        this.orientation.removeEventListener('change', this.listener);
      } else {
        window.removeEventListener('orientationchange', this.listener);
      }
    }
  }
  async supportsOrientationLockAsync(orientationLock: OrientationLock): Promise<boolean> {
    return orientationLock in OrientationLockAPIToWeb;
  }
  async getPlatformOrientationLockAsync(): Promise<WebOrientationLock> {
    return _lastWebOrientationLock;
  }
  async getOrientationAsync(): Promise<Orientation> {
    const webOrientation =
      screen['msOrientation'] || (screen.orientation || screen['mozOrientation'] || {}).type;
    if (!webOrientation) {
      return Orientation.UNKNOWN;
    }
    return OrientationWebToAPI[webOrientation];
  }
  async lockAsync(orientationLock: OrientationLock): Promise<void> {
    const webOrientationLock = OrientationLockAPIToWeb[orientationLock];
    if (!webOrientationLock) {
      throw new TypeError(`Invalid Orientation Lock: ${orientationLock}`);
    }
    await _lockAsync(webOrientationLock);
  }
  async lockPlatformAsync(webOrientationLock: WebOrientationLock): Promise<void> {
    await _lockAsync(webOrientationLock);
    _lastWebOrientationLock = webOrientationLock;
  }
  async unlockAsync(): Promise<void> {
    if (screen.orientation && screen.orientation.unlock) {
      screen.orientation.unlock();
    } else if (
      screen['unlockOrientation'] ||
      screen['mozUnlockOrientation'] ||
      screen['msUnlockOrientation']
    ) {
      const unlockOrientation =
        screen['unlockOrientation'] ||
        screen['mozUnlockOrientation'] ||
        screen['msUnlockOrientation'];
      // correct `this` context must be passed in otherwise method call is disallowed by browser
      const isSuccess = unlockOrientation.call(screen);
      if (!isSuccess) {
        throw new Error(`Unlocking screen orientation on device was denied`);
      }
    } else {
      throw new Error(
        `expo-screen-orientation: The browser doesn't support unlocking screen orientation.`
      );
    }
  }
}

export default registerWebModule(ExpoScreenOrientation);