import { FastifyInstance, FastifyRequest } from 'fastify';
import { spawn } from 'child_process';
import { getCommand } from '../whitelist.js';

interface ExecBody {
  command_key: string;
  args?: string[];
}

export async function execRoutes(app: FastifyInstance): Promise<void> {
  app.post('/agent/v1/exec', async (req: FastifyRequest<{ Body: ExecBody }>, reply) => {
    const { command_key, args = [] } = req.body;

    const def = getCommand(command_key);
    if (!def) {
      return reply
        .status(403)
        .send({ error: `command_key '${command_key}' is not in the whitelist` });
    }

    reply.raw.writeHead(200, {
      'Content-Type': 'text/event-stream',
      'Cache-Control': 'no-cache',
      Connection: 'keep-alive',
    });

    const sendEvent = (event: string, data: string) => {
      reply.raw.write(`event: ${event}\ndata: ${JSON.stringify({ data })}\n\n`);
    };

    const [bin, ...staticArgs] = def.exec.split(' ');
    const child = spawn(bin, [...staticArgs, ...args], { shell: false });

    child.stdout.on('data', (chunk: Buffer) => {
      sendEvent('stdout', chunk.toString());
    });

    child.stderr.on('data', (chunk: Buffer) => {
      sendEvent('stderr', chunk.toString());
    });

    child.on('close', (code) => {
      reply.raw.write(`event: exit\ndata: ${JSON.stringify({ code })}\n\n`);
      reply.raw.end();
    });

    child.on('error', (err) => {
      reply.raw.write(`event: error\ndata: ${JSON.stringify({ message: err.message })}\n\n`);
      reply.raw.end();
    });

    req.raw.on('close', () => {
      child.kill();
    });
  });
}