import express from "express";
import { createHandler } from "graphql-http/lib/use/http";
import { buildSchema } from "graphql";
import { ruruHTML } from "ruru/server";
import { serveStatic } from "ruru/static";
import { generateDefinitions } from "../generateLexiconSchema";

// Initialize Express app
const app = express();

const lexiconIds = (await import("../../lexicons.json")).lexicons;

// Generate definitions (this is what main.ts does when no --output flag is provided)
const { chunks: generatedDefinitions, lexiconCalls } =
  generateDefinitions(lexiconIds);

// Define GraphQL schema using GraphQL-JS
const schema = buildSchema(
  generatedDefinitions.join("\n\n") +
    `
type Query {
  lexicon: Lexicon
}`,
);

const ty = (schema.getQueryType().getFields()["lexicon"].resolve = () => ({}));

// Serve static files
for (const key of Object.keys(lexiconCalls)) {
  const segments = key.split(".");
  const ty = schema.getType(
    ["Lexicon"].concat(segments.slice(0, -1)).join("_"),
  );
  ty.getFields()[segments.slice(-1)[0]].resolve = lexiconCalls[key];

  for (let i = 1; i < segments.length; i++) {
    const ty = schema.getType(
      ["Lexicon"].concat(segments.slice(0, i - 1)).join("_"),
    );
    ty.getFields()[segments.slice(0, i).pop()].resolve = () => ({});
  }
}

app.use(express.static("public"));

// Serve lexicons.json at /lexicons path
app.get("/lexicons", (req, res) => {
  res.json(Object.keys(lexiconCalls));
});

const handler = createHandler({ schema });

// GraphQL endpoint
app.all("/graphql", handler);

/**
 * Setup GraphiQL
 */

const config = { staticPath: "/ruru-static/", endpoint: "/graphql" };

// Serve Ruru HTML
app.get("/graphiql", (req, res) => {
  res.format({
    html: () => res.status(200).send(ruruHTML(config)),
    default: () => res.status(406).send("Not Acceptable"),
  });
});

// Serve static files
app.use(serveStatic(config.staticPath));

// Start the HTTP server
const PORT = process.env.PORT || 4000;
const httpServer = app.listen(PORT, () => {
  console.log(`Server ready at http://localhost:${PORT}`);
  console.log(`GraphQL endpoint: http://localhost:${PORT}/graphql`);
  console.log(`GraphiQL endpoint: http://localhost:${PORT}/graphiql`);
});

// Handle server shutdown gracefully
process.on("SIGINT", () => {
  httpServer.close(() => {
    console.log("Server closed");
  });
});