import type { IncomingMessage, ServerResponse } from 'node:http';
import { CLOUD_AGENTS_PATH } from '../../../shared/cloud-agents';
import { CloudAgentsError, CloudAgentsModule } from '../../services/cloud-agents';
import { parseJsonBody, sendJson, flushStreamingHeaders, writeStreamingChunk } from '../route-utils';

const cloudAgents = new CloudAgentsModule();

export async function handleCloudAgentsRoutes(req: IncomingMessage, res: ServerResponse, url: URL): Promise<boolean> {
  if (!url.pathname.startsWith(CLOUD_AGENTS_PATH + '/')) return false;
  res.setHeader('Cache-Control', 'no-store');
  const path = url.pathname.slice(CLOUD_AGENTS_PATH.length);
  try {
    let data: unknown;
    const stream = /^\/runs\/([a-zA-Z0-9_-]{1,64})\/events$/.exec(path);
    if (stream && req.method === 'GET') {
      const controller = new AbortController();
      const decoder = new TextDecoder();
      const close = () => controller.abort();
      res.once('close', close);
      try {
        const after = (typeof req.headers['last-event-id'] === 'string' ? req.headers['last-event-id'] : null)
          ?? url.searchParams.get('after_seq') ?? '0-0';
        for await (const chunk of cloudAgents.events(stream[1], after, controller.signal)) {
          if (!res.headersSent) {
            res.setHeader('Content-Type', 'text/event-stream; charset=utf-8');
            res.setHeader('Connection', 'keep-alive');
            flushStreamingHeaders(res);
          }
          if (!await writeStreamingChunk(res, decoder.decode(chunk, { stream: true }))) break;
        }
      } finally {
        controller.abort();
        res.off('close', close);
      }
      res.end();
      return true;
    }
    if (path === '/recovery' && req.method === 'GET') {
      data = await cloudAgents.recovery();
    } else if (path === '/recovery/recent' && req.method === 'PUT') {
      data = await cloudAgents.rememberRecent(await parseJsonBody(req));
    } else if (path === '/recovery/pending' && req.method === 'POST') {
      data = await cloudAgents.resolvePending(await parseJsonBody(req));
    } else if (path === '/attachments/pick' && req.method === 'POST') {
      data = await cloudAgents.upload();
    } else if (path === '/knowledge/pick' && req.method === 'POST') {
      data = await cloudAgents.uploadKnowledge(await parseJsonBody(req));
    } else if (path === '/skills/pick' && req.method === 'POST') {
      data = await cloudAgents.uploadSkill();
    } else if (path === '/files/save' && req.method === 'POST') {
      data = await cloudAgents.download(await parseJsonBody(req));
    } else if (path === '/actions' && req.method === 'POST') {
      data = await cloudAgents.execute(await parseJsonBody(req));
    } else if ((path === '/bootstrap' || path === '/agents') && req.method === 'GET') {
      data = await cloudAgents.list(url.searchParams.get('cursor'), url.searchParams.get('archived') === 'true');
    } else if (path === '/agents' && req.method === 'POST') {
      data = await cloudAgents.create(await parseJsonBody(req));
    } else {
      const match = /^\/agents\/(ml-[a-f0-9]{32})(\/draft)?$/.exec(path);
      if (match && !match[2] && req.method === 'GET') data = await cloudAgents.get(match[1]);
      else if (match && match[2] && req.method === 'PATCH') data = await cloudAgents.save(match[1], await parseJsonBody(req));
      else {
        sendJson(res, 404, { error: '智能体接口不存在' });
        return true;
      }
    }
    sendJson(res, 200, data);
  } catch (error) {
    const failure = error instanceof CloudAgentsError ? error
      : new CloudAgentsError(error instanceof SyntaxError ? 400 : 502, error instanceof SyntaxError ? 'invalid_input' : 'cloud_service_unavailable');
    if (res.headersSent) res.end();
    else sendJson(res, failure.status, { success: false, error: failure.message, code: failure.code });
  }
  return true;
}