feat: support acl capabilities check

app/routes/acls/overview.tsx

@@ -0,0 +1,173 @@
+import { Construction, Eye, FlaskConical, Pencil } from 'lucide-react';
+import { useEffect, useState } from 'react';
+import {
+	ActionFunctionArgs,
+	LoaderFunctionArgs,
+	useFetcher,
+	useLoaderData,
+	useRevalidator,
+} from 'react-router';
+import Button from '~/components/Button';
+import Code from '~/components/Code';
+import Link from '~/components/Link';
+import Notice from '~/components/Notice';
+import Tabs from '~/components/Tabs';
+import type { LoadContext } from '~/server';
+import toast from '~/utils/toast';
+import { aclAction } from './acl-action';
+import { aclLoader } from './acl-loader';
+import { Differ, Editor } from './components/cm.client';
+import { ErrorView, NoticeView } from './components/error';
+
+export async function loader(request: LoaderFunctionArgs<LoadContext>) {
+	return aclLoader(request);
+}
+
+export async function action(request: ActionFunctionArgs<LoadContext>) {
+	return aclAction(request);
+}
+
+export default function Page() {
+	// Access is a write check here, we already check read in aclLoader
+	const { access, writable, policy } = useLoaderData<typeof loader>();
+	const [codePolicy, setCodePolicy] = useState(policy);
+	const fetcher = useFetcher<typeof action>();
+	const { revalidate } = useRevalidator();
+	const disabled = !access || !writable; // Disable if no permission or not writable
+
+	useEffect(() => {
+		// Update the codePolicy when the loader data changes
+		if (policy !== codePolicy) {
+			setCodePolicy(policy);
+		}
+	}, [policy]);
+
+	useEffect(() => {
+		if (!fetcher.data) {
+			// No data yet, return
+			return;
+		}
+
+		if (fetcher.data.success === true) {
+			toast('Updated policy');
+			revalidate();
+		}
+	}, [fetcher.data]);
+
+	return (
+		<div>
+			{!access ? (
+				<NoticeView title="ACL Policy restricted">
+					You do not have the necessary permissions to edit the Access Control
+					List policy. Please contact your administrator to request access or to
+					make changes to the ACL policy.
+				</NoticeView>
+			) : !writable ? (
+				<NoticeView title="Read-only ACL Policy">
+					The ACL policy mode is most likely set to <Code>file</Code> in your
+					Headscale configuration. This means that the ACL file cannot be edited
+					through the web interface. In order to resolve this, you'll need to
+					set <Code>acl.mode</Code> to <Code>database</Code> in your Headscale
+					configuration.
+				</NoticeView>
+			) : undefined}
+			<h1 className="text-2xl font-medium mb-4">Access Control List (ACL)</h1>
+			<p className="mb-4 max-w-prose">
+				The ACL file is used to define the access control rules for your
+				network. You can find more information about the ACL file in the{' '}
+				<Link
+					to="https://tailscale.com/kb/1018/acls"
+					name="Tailscale ACL documentation"
+				>
+					Tailscale ACL guide
+				</Link>{' '}
+				and the{' '}
+				<Link
+					to="https://headscale.net/stable/ref/acls/"
+					name="Headscale ACL documentation"
+				>
+					Headscale docs
+				</Link>
+				.
+			</p>
+			{fetcher.data?.error !== undefined ? (
+				<ErrorView>{fetcher.data.error}</ErrorView>
+			) : undefined}
+			<Tabs label="ACL Editor" className="mb-4">
+				<Tabs.Item
+					key="edit"
+					title={
+						<div className="flex items-center gap-2">
+							<Pencil className="p-1" />
+							<span>Edit file</span>
+						</div>
+					}
+				>
+					<Editor
+						isDisabled={disabled}
+						value={codePolicy}
+						onChange={setCodePolicy}
+					/>
+				</Tabs.Item>
+				<Tabs.Item
+					key="diff"
+					title={
+						<div className="flex items-center gap-2">
+							<Eye className="p-1" />
+							<span>Preview changes</span>
+						</div>
+					}
+				>
+					<Differ left={policy} right={codePolicy} />
+				</Tabs.Item>
+				<Tabs.Item
+					key="preview"
+					title={
+						<div className="flex items-center gap-2">
+							<FlaskConical className="p-1" />
+							<span>Preview rules</span>
+						</div>
+					}
+				>
+					<div className="flex flex-col items-center py-8">
+						<Construction />
+						<p className="w-1/2 text-center mt-4">
+							Previewing rules is not available yet. This feature is still in
+							development and is pretty complicated to implement. Hopefully I
+							will be able to get to it soon.
+						</p>
+					</div>
+				</Tabs.Item>
+			</Tabs>
+			<Button
+				variant="heavy"
+				className="mr-2"
+				isDisabled={
+					disabled ||
+					fetcher.state !== 'idle' ||
+					codePolicy.length === 0 ||
+					codePolicy === policy
+				}
+				onPress={() => {
+					const formData = new FormData();
+					console.log(codePolicy);
+					formData.append('policy', codePolicy);
+					fetcher.submit(formData, { method: 'PATCH' });
+				}}
+			>
+				Save
+			</Button>
+			<Button
+				isDisabled={
+					disabled || fetcher.state !== 'idle' || codePolicy === policy
+				}
+				onPress={() => {
+					// Reset the editor to the original policy
+					setCodePolicy(policy);
+				}}
+			>
+				Discard Changes
+			</Button>
+		</div>
+	);
+}