import { existsSync } from "node:fs";
import { join } from "node:path";
import Fastify from "fastify";
import jwt from "@fastify/jwt";
import rateLimit from "@fastify/rate-limit";
import fastifyStatic from "@fastify/static";
import formbody from "@fastify/formbody";
import { loadConfig } from "./config.js";
import { buildContext } from "./context.js";
import { authRoutes } from "./routes/auth.js";
import { webhookRoutes } from "./routes/webhook.js";
import { ticketRoutes } from "./routes/tickets.js";
import { testRoutes } from "./routes/test.js";

export async function build() {
  const config = loadConfig();
  const app = Fastify({
    logger: { level: config.LOG_LEVEL },
    trustProxy: true, // behind nginx
    bodyLimit: 1_000_000,
  });

  app.decorate("ctx", buildContext(config));

  await app.register(jwt, { secret: config.TOKEN_SECRET });
  await app.register(rateLimit, { global: false });
  await app.register(formbody); // accept application/x-www-form-urlencoded webhooks too

  await app.register(authRoutes);
  await app.register(webhookRoutes);
  await app.register(ticketRoutes);
  await app.register(testRoutes);

  // Serve the exported Expo web build (if present) with SPA fallback.
  const webDir = config.WEB_DIR ?? join(process.cwd(), "web");
  if (existsSync(webDir)) {
    await app.register(fastifyStatic, { root: webDir, wildcard: false });
    app.setNotFoundHandler((req, reply) => {
      // Let unknown /api routes 404 as JSON; everything else -> SPA index.
      if (req.raw.url && req.raw.url.startsWith("/api")) {
        return reply.code(404).send({ error: "not_found" });
      }
      return reply.sendFile("index.html");
    });
    app.log.info({ webDir }, "serving static web build");
  } else {
    app.log.warn({ webDir }, "no web build found; serving API only");
  }

  return app;
}

// Entry point (skipped when imported by tests).
const isMain = process.argv[1] && import.meta.url === `file://${process.argv[1]}`;
if (isMain) {
  const config = loadConfig();
  build()
    .then((app) => app.listen({ port: config.PORT, host: config.HOST }))
    .then((addr) => {
      // eslint-disable-next-line no-console
      console.log(`camptickets backend listening on ${addr}`);
    })
    .catch((err) => {
      // eslint-disable-next-line no-console
      console.error(err);
      process.exit(1);
    });
}