From 03d56006dc62b79aeff0b822dba2b1478473a8aa Mon Sep 17 00:00:00 2001
From: h <h@kotikot.com>
Date: Wed, 21 Jan 2026 10:20:17 +0100
Subject: [PATCH] feat(frontend): POST for images

---
 caddy/Caddyfile.example                   |  3 +
 frontend/src/app.d.ts                     | 12 ++-
 frontend/src/hooks.server.ts              |  8 ++
 frontend/src/routes/[mnemonic]/+server.ts | 91 +++++++++++++++++++++++
 4 files changed, 107 insertions(+), 7 deletions(-)
 create mode 100644 frontend/src/hooks.server.ts
 create mode 100644 frontend/src/routes/[mnemonic]/+server.ts

diff --git a/caddy/Caddyfile.example b/caddy/Caddyfile.example
index 945d10c..5e53783 100644
--- a/caddy/Caddyfile.example
+++ b/caddy/Caddyfile.example
@@ -26,6 +26,9 @@
     }
 
     handle {
+        request_body {
+            max_size 50MB
+        }
         reverse_proxy stealth-ai-relay-frontend:3000
     }
 }
diff --git a/frontend/src/app.d.ts b/frontend/src/app.d.ts
index da08e6d..785b0e4 100644
--- a/frontend/src/app.d.ts
+++ b/frontend/src/app.d.ts
@@ -1,12 +1,10 @@
-// See https://svelte.dev/docs/kit/types#app.d.ts
-// for information about these interfaces
+import type { ConvexHttpClient } from 'convex/browser';
+
 declare global {
 	namespace App {
-		// interface Error {}
-		// interface Locals {}
-		// interface PageData {}
-		// interface PageState {}
-		// interface Platform {}
+		interface Locals {
+			convex: ConvexHttpClient;
+		}
 	}
 }
 
diff --git a/frontend/src/hooks.server.ts b/frontend/src/hooks.server.ts
new file mode 100644
index 0000000..77eff0a
--- /dev/null
+++ b/frontend/src/hooks.server.ts
@@ -0,0 +1,8 @@
+import { ConvexHttpClient } from 'convex/browser';
+import { PUBLIC_CONVEX_URL } from '$env/static/public';
+import type { Handle } from '@sveltejs/kit';
+
+export const handle: Handle = async ({ event, resolve }) => {
+	event.locals.convex = new ConvexHttpClient(PUBLIC_CONVEX_URL);
+	return resolve(event);
+};
diff --git a/frontend/src/routes/[mnemonic]/+server.ts b/frontend/src/routes/[mnemonic]/+server.ts
new file mode 100644
index 0000000..006768c
--- /dev/null
+++ b/frontend/src/routes/[mnemonic]/+server.ts
@@ -0,0 +1,91 @@
+import { api } from '$lib/convex/_generated/api';
+import { error } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+
+function detectImageType(bytes: Uint8Array): string | null {
+	if (bytes[0] === 0xff && bytes[1] === 0xd8 && bytes[2] === 0xff) {
+		return 'image/jpeg';
+	}
+	if (bytes[0] === 0x89 && bytes[1] === 0x50 && bytes[2] === 0x4e && bytes[3] === 0x47) {
+		return 'image/png';
+	}
+	if (bytes[0] === 0x47 && bytes[1] === 0x49 && bytes[2] === 0x46) {
+		return 'image/gif';
+	}
+	if (bytes[0] === 0x52 && bytes[1] === 0x49 && bytes[2] === 0x46 && bytes[3] === 0x46) {
+		return 'image/webp';
+	}
+	return null;
+}
+
+export const POST: RequestHandler = async ({ params, request, locals }) => {
+	const mnemonic = params.mnemonic;
+
+	const chatData = await locals.convex.query(api.chats.getByMnemonic, { mnemonic });
+	if (!chatData) {
+		throw error(404, 'Chat not found');
+	}
+
+	const rawContentType = request.headers.get('content-type') || '';
+	const caption = request.headers.get('x-caption') || '';
+
+	console.log('[POST /{mnemonic}] headers:', Object.fromEntries(request.headers.entries()));
+	console.log('[POST /{mnemonic}] content-type:', rawContentType);
+
+	let base64: string;
+	let mediaType: string;
+
+	if (rawContentType.includes('multipart/form-data')) {
+		const formData = await request.formData();
+		const keys = [...formData.keys()];
+		console.log('[POST /{mnemonic}] formData keys:', keys);
+
+		let file: File | null = null;
+		for (const key of ['file', 'image', 'photo', 'upload', 'attachment', ...keys]) {
+			const value = formData.get(key);
+			if (value instanceof File) {
+				file = value;
+				console.log('[POST /{mnemonic}] found file in field:', key);
+				break;
+			}
+		}
+
+		if (!file) {
+			throw error(400, `No file found in form data. Keys: ${keys.join(', ')}`);
+		}
+
+		const buffer = await file.arrayBuffer();
+		const bytes = new Uint8Array(buffer);
+		base64 = Buffer.from(buffer).toString('base64');
+		mediaType = detectImageType(bytes) || file.type || 'image/jpeg';
+
+		console.log('[POST /{mnemonic}] file:', file.name, file.type, 'size:', buffer.byteLength);
+	} else if (rawContentType.includes('application/x-www-form-urlencoded')) {
+		throw error(400, 'Use Form with File field, not URL-encoded form');
+	} else {
+		const buffer = await request.arrayBuffer();
+		const bytes = new Uint8Array(buffer);
+		base64 = Buffer.from(buffer).toString('base64');
+		mediaType = detectImageType(bytes) || rawContentType || 'image/jpeg';
+
+		console.log('[POST /{mnemonic}] raw bytes size:', buffer.byteLength);
+		console.log('[POST /{mnemonic}] detected type:', mediaType);
+	}
+
+	if (!base64 || base64.length === 0) {
+		throw error(400, 'Empty image data');
+	}
+
+	await locals.convex.mutation(api.messages.create, {
+		chatId: chatData._id,
+		role: 'user',
+		content: caption,
+		source: 'web',
+		imageBase64: base64,
+		imageMediaType: mediaType
+	});
+
+	return new Response(JSON.stringify({ ok: true, mediaType, size: base64.length }), {
+		headers: { 'Content-Type': 'application/json' }
+	});
+};