app/api/vision-agent/route.ts

import { OpenAIStream, StreamingTextResponse } from 'ai';

import { auth } from '@/auth';
import {
  AIStream,
  type AIStreamParser,
  type AIStreamCallbacksAndOptions,
} from 'ai';
import { MessageBase } from '../../../lib/types';
import { fetcher } from '@/lib/utils';

export const runtime = 'edge';

function parseVisionAgentStream(): AIStreamParser {
  let previous = '';

  return data => {
    console.log('[Ming] ~ parseVisionAgentStream ~ data:', data);
    // const json = JSON.parse(data) as {
    //   completion: string;
    //   stop: string | null;
    //   stop_reason: string | null;
    //   truncated: boolean;
    //   log_id: string;
    //   model: string;
    //   exception: string | null;
    // };

    // // Anthropic's `completion` field is cumulative unlike OpenAI's
    // // deltas. In order to compute the delta, we must slice out the text
    // // we previously received.
    // const text = json.completion;
    // console.log('[Ming] ~ parseVisionAgentStream ~ text:', text);
    // const delta = text.slice(previous.length);
    // previous = text;

    return data;
  };
}

function visionAgentStream(
  res: Response,
  cb?: AIStreamCallbacksAndOptions,
): ReadableStream {
  return AIStream(res, parseVisionAgentStream(), cb);
}

function readChunks(reader: any) {
  return {
    async *[Symbol.asyncIterator]() {
      let readResult = await reader.read();
      while (!readResult.done) {
        yield readResult.value;
        readResult = await reader.read();
      }
    },
  };
}

export async function POST(req: Request) {
  const json = await req.json();
  const { messages, url } = json as {
    messages: MessageBase[];
    id: string;
    url: string;
  };

  const session = await auth();
  if (!session?.user?.email) {
    return new Response('Unauthorized', {
      status: 401,
    });
  }

  const formData = new FormData();
  formData.append('input', JSON.stringify(messages));
  formData.append('image', url);

  const fetchResponse = await fetch(
    'https://api.dev.landing.ai/v1/agent/chat?agent_class=vision_agent',
    // 'http://localhost:5050/v1/agent/chat?agent_class=vision_agent',
    {
      method: 'POST',
      headers: {
        apikey: 'land_sk_DKeoYtaZZrYqJ9TMMiXe4BIQgJcZ0s3XAoB0JT3jv73FFqnr6k',
      },
      body: formData,
    },
  );

  // console.log('[Ming] ~ POST ~ fetchResponse:', fetchResponse);

  if (fetchResponse.body) {
    return new StreamingTextResponse(fetchResponse.body);
  } else {
    return fetchResponse;
  }
}