Refactor HighlightedCode

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

src/components/common/async-library-loading-boundary.tsx

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+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React, { Fragment } from 'react'
+import { Trans, useTranslation } from 'react-i18next'
+import { WaitSpinner } from './wait-spinner/wait-spinner'
+import { Alert } from 'react-bootstrap'
+
+export interface AsyncLoadingBoundaryProps {
+  loading: boolean
+  error?: Error
+  componentName: string
+}
+
+/**
+ * Indicates that a component currently loading or an error occurred.
+ * It's meant to be used in combination with useAsync from react-use.
+ *
+ * @param loading Indicates that the component is currently loading. Setting this will show a spinner instead of the children.
+ * @param error Indicates that an error occurred during the loading process. Setting this to any non-null value will show an error message instead of the children.
+ * @param libraryName The name of the component that is currently loading. It will be shown in the error message.
+ * @param children The child {@link ReactElement elements} that are only shown if the component isn't in loading or error state
+ */
+export const AsyncLibraryLoadingBoundary: React.FC<AsyncLoadingBoundaryProps> = ({
+  loading,
+  error,
+  componentName,
+  children
+}) => {
+  useTranslation()
+  if (error) {
+    return (
+      <Alert variant={'danger'}>
+        <Trans i18nKey={'common.errorWhileLoading'} values={{ name: componentName }} />
+      </Alert>
+    )
+  } else if (loading) {
+    return <WaitSpinner />
+  } else {
+    return <Fragment>{children}</Fragment>
+  }
+}