import { APP_DATA_VERSION, dbStatusAtom, jotaiStore } from "../../src/globals";
import stepchartsUrl from "../../data/stepData.ndjson?url";
import { RpcProvider } from "worker-rpc";
import ndjsonStream from "../ndjsonStream";

async function init() {
  const rpcProvider = new RpcProvider((message, transfer) =>
    self.postMessage(message, undefined, transfer),
  );
  self.addEventListener("message", (evt) => rpcProvider.dispatch(evt.data));

  rpcProvider.registerSignalHandler("start", async () => {
    const result = await rpcProvider.rpc("db", {
      cmd: "exec",
      s: "SELECT version FROM _appDataVersion",
    });
    const appDataVersion = result[0].values[0][0];
    if (appDataVersion === APP_DATA_VERSION) {
      console.log(`data version is up to date! (${appDataVersion})`);
      return;
    }

    console.log(
      `outdated data version ${appDataVersion} < ${APP_DATA_VERSION}`,
    );
    await rpcProvider.rpc("db", {
      cmd: "run",
      s: "DELETE FROM charts",
    });

    const response = await fetch(stepchartsUrl);
    const stream = ndjsonStream<ChartData>(response.body);
    const reader = stream.getReader();
    const iter = iterStream(reader);

    // TODO: Actually stream this into the DB somehow?
    // For slow connections where this download process actually takes quite a bit
    const lol = [];
    for await (const thing of iter) {
      lol.push(thing);
    }
    console.log(lol);
    console.log(`got ${lol.length} entries. inserting...`);
    const h = await rpcProvider.rpc("db", {
      cmd: "bulkInsert",
      s: `
        INSERT INTO charts
          (artist, title, difficulty)
        VALUES ($artist, $title, $difficulty)
      `,
      data: lol,
    });

    jotaiStore.set(dbStatusAtom, (prev) => ({
      ...prev,
      lastUpdated: new Date().getTime(),
    }));
  });
}

async function* iterStream(reader: ReadableStreamReader<ChartData>) {
  let result;
  while (!result || !result.done) {
    result = await reader.read();
    if (result.value) yield result.value;
  }
}

init();