fix: proxy nextcloud requests through server

src/server/request-handler.ts

@@ -19,6 +19,34 @@ type ShareListingEntry = {
   isCollection: boolean;
 };
 
+function resolveDavUrlFromShareUrl(shareUrl: string): string {
+  const url = new URL(shareUrl);
+  const publicShare = url.pathname.match(/\/s\/([^/?#]+)/);
+
+  if (publicShare) {
+    return `${url.origin}/public.php/dav/files/${publicShare[1]}/`;
+  }
+
+  const davShare = url.pathname.match(/\/public\.php\/dav\/files\/([^/?#]+)\/?/);
+
+  if (davShare) {
+    return `${url.origin}/public.php/dav/files/${davShare[1]}/`;
+  }
+
+  throw new Error("Bitte einen öffentlichen Nextcloud-Share-Link einfügen.");
+}
+
+async function proxyUpstream(url: string, init?: RequestInit) {
+  const upstream = await fetch(url, init);
+  const body = await upstream.arrayBuffer();
+
+  return {
+    body: Buffer.from(body),
+    contentType: upstream.headers.get("content-type") ?? "application/octet-stream",
+    status: upstream.status
+  };
+}
+
 const demoPhotos: Photo[] = [
   {
     id: "demo-1",
@@ -581,7 +609,7 @@ function htmlPage(): string {
       function parseShareInput(value) {
         const trimmed = value.trim();
         const url = new URL(trimmed);
-        const publicShare = url.pathname.match(/\/s\/([^/?#]+)/);
+        const publicShare = url.pathname.match(/\\\/s\\\/([^/?#]+)/);
         if (publicShare) {
           return {
             origin: url.origin,
@@ -589,7 +617,7 @@ function htmlPage(): string {
           };
         }
 
-        const davShare = url.pathname.match(/\/public\.php\/dav\/files\/([^/?#]+)\/?/);
+        const davShare = url.pathname.match(/\\\/public\\.php\\\/dav\\\/files\\\/([^/?#]+)\\\/?/);
         if (davShare) {
           return {
             origin: url.origin,
@@ -640,36 +668,19 @@ function htmlPage(): string {
       }
 
       async function loadShareListing(davUrl) {
-        const response = await fetch(davUrl, {
-          method: "PROPFIND",
-          mode: "cors",
-          headers: {
-            Depth: "1",
-            "Content-Type": "application/xml; charset=utf-8",
-            Accept: "application/xml, text/xml"
-          },
-          body:
-            '<?xml version="1.0" encoding="UTF-8"?>' +
-            '<d:propfind xmlns:d="DAV:">' +
-              "<d:prop>" +
-                "<d:displayname/>" +
-                "<d:getlastmodified/>" +
-                "<d:getcontenttype/>" +
-                "<d:getcontentlength/>" +
-                "<d:resourcetype/>" +
-              "</d:prop>" +
-            "</d:propfind>"
-        });
+        const response = await fetch(
+          "/api/nextcloud/list?share=" + encodeURIComponent(shareUrl.value.trim())
+        );
 
         if (!response.ok) {
-          throw new Error("WebDAV hat mit Status " + response.status + " geantwortet.");
+          throw new Error("Nextcloud-Liste konnte nicht geladen werden: " + response.status);
         }
 
         return parseListing(await response.text(), davUrl);
       }
 
       async function readRemotePhoto(entry) {
-        const response = await fetch(entry.href, { mode: "cors" });
+        const response = await fetch("/api/nextcloud/blob?url=" + encodeURIComponent(entry.href));
         if (!response.ok) {
           throw new Error("Bild konnte nicht geladen werden: " + entry.name);
         }
@@ -781,6 +792,84 @@ export function createRequestHandler() {
       return;
     }
 
+    if (url.pathname === "/api/nextcloud/list") {
+      const share = url.searchParams.get("share");
+
+      if (!share) {
+        res.statusCode = 400;
+        res.setHeader("content-type", "application/json; charset=utf-8");
+        res.end(JSON.stringify({ error: "share parameter missing" }));
+        return;
+      }
+
+      try {
+        const davUrl = resolveDavUrlFromShareUrl(share);
+        const xml =
+          '<?xml version="1.0" encoding="UTF-8"?>' +
+          '<d:propfind xmlns:d="DAV:">' +
+            "<d:prop>" +
+              "<d:displayname/>" +
+              "<d:getlastmodified/>" +
+              "<d:getcontenttype/>" +
+              "<d:getcontentlength/>" +
+              "<d:resourcetype/>" +
+            "</d:prop>" +
+          "</d:propfind>";
+
+        const upstream = await proxyUpstream(davUrl, {
+          method: "PROPFIND",
+          headers: {
+            Depth: "1",
+            "Content-Type": "application/xml; charset=utf-8",
+            Accept: "application/xml, text/xml"
+          },
+          body: xml
+        });
+
+        res.statusCode = upstream.status;
+        res.setHeader("content-type", upstream.contentType);
+        res.end(upstream.body);
+        return;
+      } catch (error) {
+        res.statusCode = 502;
+        res.setHeader("content-type", "application/json; charset=utf-8");
+        res.end(
+          JSON.stringify({
+            error: error instanceof Error ? error.message : "upstream request failed"
+          })
+        );
+        return;
+      }
+    }
+
+    if (url.pathname === "/api/nextcloud/blob") {
+      const target = url.searchParams.get("url");
+
+      if (!target) {
+        res.statusCode = 400;
+        res.setHeader("content-type", "application/json; charset=utf-8");
+        res.end(JSON.stringify({ error: "url parameter missing" }));
+        return;
+      }
+
+      try {
+        const upstream = await proxyUpstream(target);
+        res.statusCode = upstream.status;
+        res.setHeader("content-type", upstream.contentType);
+        res.end(upstream.body);
+        return;
+      } catch (error) {
+        res.statusCode = 502;
+        res.setHeader("content-type", "application/json; charset=utf-8");
+        res.end(
+          JSON.stringify({
+            error: error instanceof Error ? error.message : "upstream request failed"
+          })
+        );
+        return;
+      }
+    }
+
     res.statusCode = 200;
     res.setHeader("content-type", "text/html; charset=utf-8");
     res.end(htmlPage());