✨(front) add switch camera on mobile

We want to have a more simple control bar and give the user to switch
its back / front camera from the responsive menu.

src/frontend/src/features/rooms/livekit/components/controls/CameraSwitchButton.tsx

@@ -0,0 +1,123 @@
+import { Button } from '@/primitives'
+import { useMediaDeviceSelect } from '@livekit/components-react'
+import { RiCameraSwitchLine } from '@remixicon/react'
+import { useEffect, useState } from 'react'
+import { ButtonProps } from 'react-aria-components'
+import { useTranslation } from 'react-i18next'
+
+enum FacingMode {
+  USER = 'user',
+  ENVIRONMENT = 'environment',
+}
+
+export const CameraSwitchButton = (props: Partial<ButtonProps>) => {
+  const { t } = useTranslation('rooms')
+
+  const { devices, activeDeviceId, setActiveMediaDevice } =
+    useMediaDeviceSelect({
+      kind: 'videoinput',
+      requestPermissions: true,
+    })
+
+  // getCapabilities type is not available.
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const getDeviceFacingMode = (device: any): string[] => {
+    if (!device.getCapabilities) {
+      return []
+    }
+    const capabilities = device.getCapabilities()
+    if (!capabilities) {
+      return []
+    }
+    if (typeof capabilities.facingMode !== 'object') {
+      return []
+    }
+    return capabilities.facingMode
+  }
+
+  const detectCurrentFacingMode = (): FacingMode | null => {
+    if (!activeDeviceId) {
+      return null
+    }
+    const activeDevice = devices.find(
+      (device) => device.deviceId === activeDeviceId
+    )
+    if (!activeDevice) {
+      return null
+    }
+    const facingMode = getDeviceFacingMode(activeDevice)
+    if (facingMode.indexOf(FacingMode.USER) >= 0) {
+      return FacingMode.USER
+    }
+    if (facingMode.indexOf(FacingMode.ENVIRONMENT) >= 0) {
+      return FacingMode.ENVIRONMENT
+    }
+    return null
+  }
+
+  const guessCurrentFacingMode = () => {
+    const facingMode = detectCurrentFacingMode()
+    if (facingMode) {
+      return facingMode
+    }
+    // We consider by default if we have no clue that the user camera is used.
+    return FacingMode.USER
+  }
+
+  const [facingMode, setFacingMode] = useState<FacingMode | null>()
+
+  /**
+   * Before setting the initial value of facingMode we need to wait for devices to
+   * be loaded ( because in detectCurrentFacingMode we need to find the active device
+   * in the devices list ), which is not the case at first render.
+   */
+  useEffect(() => {
+    if (devices.length == 0) {
+      return
+    }
+    if (facingMode) {
+      return
+    }
+
+    setFacingMode(guessCurrentFacingMode())
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [devices])
+
+  const getUserDevice = (
+    facingMode: FacingMode
+  ): MediaDeviceInfo | undefined => {
+    return devices.find((device) => {
+      return getDeviceFacingMode(device).indexOf(facingMode) >= 0
+    })
+  }
+
+  const toggle = () => {
+    let target: FacingMode
+    if (facingMode === FacingMode.USER) {
+      target = FacingMode.ENVIRONMENT
+    } else {
+      target = FacingMode.USER
+    }
+    const device = getUserDevice(target)
+    if (device) {
+      setActiveMediaDevice(device.deviceId)
+      setFacingMode(target)
+    } else {
+      console.error('Cannot get user device with facingMode ' + target)
+    }
+  }
+  return (
+    <Button
+      onPress={(e) => {
+        toggle()
+        props.onPress?.(e)
+      }}
+      variant="primaryTextDark"
+      aria-label={t('options.items.switchCamera')}
+      tooltip={t('options.items.switchCamera')}
+      description={true}
+    >
+      <RiCameraSwitchLine size={20} />
+    </Button>
+  )
+}

src/frontend/src/features/rooms/livekit/prefabs/ControlBar/MobileControlBar.tsx

@@ -23,6 +23,7 @@ import { LinkButton } from '@/primitives'
 import { useSettingsDialog } from '../../components/controls/SettingsDialogContext'
 import { ResponsiveMenu } from './ResponsiveMenu'
 import { TranscriptToggle } from '../../components/controls/TranscriptToggle'
+import { CameraSwitchButton } from '../../components/controls/CameraSwitchButton'
 
 export function MobileControlBar({
   onDeviceError,
@@ -176,6 +177,7 @@ export function MobileControlBar({
             >
               <RiSettings3Line size={20} />
             </Button>
+            <CameraSwitchButton onPress={() => setIsMenuOpened(false)} />
           </div>
         </div>
       </ResponsiveMenu>

src/frontend/src/locales/de/rooms.json

@@ -83,7 +83,8 @@
       "feedback": "",
       "settings": "",
       "username": "",
-      "effects": ""
+      "effects": "",
+      "switchCamera": ""
     }
   },
   "effects": {

src/frontend/src/locales/en/rooms.json

@@ -82,7 +82,8 @@
       "feedback": "Give us feedback",
       "settings": "Settings",
       "username": "Update Your Name",
-      "effects": "Apply effects"
+      "effects": "Apply effects",
+      "switchCamera": "Switch camera"
     }
   },
   "effects": {

src/frontend/src/locales/fr/rooms.json

@@ -82,7 +82,8 @@
       "feedback": "Partager votre avis",
       "settings": "Paramètres",
       "username": "Choisir votre nom",
-      "effects": "Appliquer des effets"
+      "effects": "Appliquer des effets",
+      "switchCamera": "Changer de caméra"
     }
   },
   "effects": {