fix: Move content into to frontend directory

Doing this BEFORE the merge prevents a lot of merge conflicts.

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

frontend/src/components/intro-page/cover-buttons/cover-buttons.module.scss

@@ -0,0 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+.cover-button {
+  min-width: 200px;
+}

frontend/src/components/intro-page/cover-buttons/cover-buttons.tsx

@@ -0,0 +1,41 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React from 'react'
+import { Button } from 'react-bootstrap'
+import { Trans, useTranslation } from 'react-i18next'
+import { useApplicationState } from '../../../hooks/common/use-application-state'
+import { ShowIf } from '../../common/show-if/show-if'
+import { SignInButton } from '../../landing-layout/navigation/sign-in-button'
+import './cover-buttons.module.scss'
+import { cypressId } from '../../../utils/cypress-attribute'
+import Link from 'next/link'
+
+export const CoverButtons: React.FC = () => {
+  useTranslation()
+  const userExists = useApplicationState((state) => !!state.user)
+  const anyAuthProviderActivated = useApplicationState((state) => state.config.authProviders.length > 0)
+
+  if (userExists) {
+    return null
+  }
+
+  return (
+    <div className='mb-5'>
+      <SignInButton className='cover-button' variant='success' size='lg' />
+      <ShowIf condition={anyAuthProviderActivated}>
+        <span className='m-2'>
+          <Trans i18nKey='common.or' />
+        </span>
+      </ShowIf>
+      <Link href='/n/features' passHref={true}>
+        <Button {...cypressId('features-button')} className='cover-button' variant='primary' size='lg'>
+          <Trans i18nKey='landing.intro.exploreFeatures' />
+        </Button>
+      </Link>
+    </div>
+  )
+}

frontend/src/components/intro-page/intro-custom-content.tsx

@@ -0,0 +1,40 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React, { useEffect } from 'react'
+import { RenderIframe } from '../editor-page/renderer-pane/render-iframe'
+import { RendererType } from '../render-page/window-post-message-communicator/rendering-message'
+import { fetchFrontPageContent } from './requests'
+import { Logger } from '../../utils/logger'
+import { useAsync } from 'react-use'
+import { AsyncLoadingBoundary } from '../common/async-loading-boundary'
+
+const logger = new Logger('Intro Content')
+
+/**
+ * Fetches the content for the customizable part of the intro page and renders it.
+ */
+export const IntroCustomContent: React.FC = () => {
+  const { value, error, loading } = useAsync(async () => (await fetchFrontPageContent()).split('\n'), [])
+
+  useEffect(() => {
+    if (error) {
+      logger.error('Error while loading custom intro content', error)
+    }
+  }, [error])
+
+  return (
+    <AsyncLoadingBoundary loading={loading} error={error} componentName={'custom intro content'}>
+      <RenderIframe
+        frameClasses={'w-100 overflow-y-hidden'}
+        markdownContentLines={value as string[]}
+        rendererType={RendererType.INTRO}
+        forcedDarkMode={true}
+        adaptFrameHeightToContent={true}
+      />
+    </AsyncLoadingBoundary>
+  )
+}

frontend/src/components/intro-page/requests.ts

@@ -0,0 +1,25 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { defaultConfig } from '../../api/common/default-config'
+
+/**
+ * Get the intro.md contents from the public directory.
+ *
+ * @return The content of intro.md
+ * @throws {Error} if the content can't be fetched
+ */
+export const fetchFrontPageContent = async (): Promise<string> => {
+  const response = await fetch('public/intro.md', {
+    ...defaultConfig,
+    method: 'GET'
+  })
+  if (response.status !== 200) {
+    throw new Error('Error fetching intro content')
+  }
+
+  return await response.text()
+}