import Fastify from "fastify";
import fastifyStatic from "@fastify/static";
import { exec } from "node:child_process";
import { promisify } from "node:util";
import path from "node:path";
import crypto from "node:crypto";

const { WEBHOOK_SECRET } = process.env;

const execAsync = promisify(exec);
const fastify = Fastify({ logger: true });

fastify.register(fastifyStatic, {
  root: path.join(process.cwd(), "dist"),
  prefix: "/",
});

const verifySignature = (payload, signature) => {
  const hmac = crypto.createHmac("sha256", WEBHOOK_SECRET);
  const digest = "sha256=" + hmac.update(payload).digest("hex");
  return crypto.timingSafeEqual(Buffer.from(digest), Buffer.from(signature));
};

const updateRepo = async (repoUrl) => {
  try {
    const { code } = await execAsync("git rev-parse --git-dir")
      .then(() => ({ code: 0 }))
      .catch((error) => ({ code: error.code }));

    if (code !== 0) {
      await execAsync("git init");
      await execAsync(`git remote add origin ${repoUrl}`);
    }

    await execAsync("git fetch origin");
    await execAsync("git reset --hard origin/main");
    await execAsync("npm run build");
  } catch (error) {
    console.error("Failed to update repository:", error);
    throw error;
  }
};

fastify.post("/webhook/rebuild", async (request, reply) => {
  const signature = request.headers["x-gitea-signature"];

  if (!signature || !verifySignature(JSON.stringify(request.body), signature)) {
    return reply.status(401).send("Invalid signature");
  }

  try {
    const repoUrl = request.body.repository.clone_url;
    await updateRepo(repoUrl);
    reply.status(200).send("Updated successfully");
  } catch (error) {
    reply.status(500).send("Update failed");
  }
});

fastify.listen({ port: 3000, host: "0.0.0.0" }, (err) => {
  if (err) {
    fastify.log.error(err);
    process.exit(1);
  }
});