import { Application, Router } from "@oak/oak";
import { XMLParser } from "npm:fast-xml-parser";

const router = new Router();

let wsClients: WebSocket[] = [];

router.get("/", (context) => {
  if (context.isUpgradable) {
    const ws = context.upgrade();
    ws.onopen = () => wsClients.push(ws);
    ws.onclose = () => wsClients = wsClients.filter((client) => client != ws);
  }
});

router
  .get("/statusline", async (ctx) => {
    ctx.response.body = await Deno.readFile("web/statusline.html");
  })
  .get("/statusline.js", async (ctx) => {
    ctx.response.body = await Deno.readFile("web/statusline.js");
  })
  .get("/gone", async (ctx) => {
    ctx.response.body = await Deno.readFile("web/gone.html");
  })
  .get("/gone.js", async (ctx) => {
    ctx.response.body = await Deno.readFile("web/gone.js");
  })
  .get("/style.css", async (ctx) => {
    ctx.response.body = await Deno.readFile("web/style.css");
  });

const app = new Application();
app.use(router.routes());
app.use(router.allowedMethods());

app.addEventListener("listen", ({ hostname, port }) => {
  console.log(`Start listening on ${hostname}:${port}`);
});

app.listen({ port: 8012 });

const topic =
  "Something Fun For Everyone With Streamboy!!!!!!!! git.jeevio.xyz/jeeves/streamboy";

setInterval(async () => {
  let songinfo: SongInfo | null = null;
  try {
    songinfo = await getVlcSongInfo();
  } catch (e) {
    console.log(`getVlcSongInfo() error: ${e}`);
    // properly handling this error is by ignoring it,
    // since then that leaves songinfo as null,
    // and that is guaranteed to be handled correctly.
  }

  const data = {
    blocks: [{ text: topic, color: "#ffffff" }],
  };
  if (songinfo != null) {
    data.blocks.push({
      text: `♪ ${songinfo.title} - ${songinfo.artist}`,
      color: "#ffffff",
    });
  }
  for (const ws of wsClients) {
    ws.send(JSON.stringify(data));
  }
}, 900);

interface SongInfo {
  title?: string;
  artist?: string;
  album?: string;
}

async function getVlcSongInfo(): Promise<SongInfo> {
  const parser = new XMLParser({ ignoreAttributes: false });
  const password = "1234";

  const res = await fetch("http://localhost:8080/requests/status.xml", {
    headers: { authorization: `Basic ${btoa(`:${password}`)}` },
  });

  const json = parser.parse(await res.text());

  const songinfo: SongInfo = {};

  try {
    for (const category of json.root.information.category) {
      if (category["@_name"] != "meta") continue;
      for (const property of category.info) {
        if (property["@_name"] == "title") {
          songinfo.title = processBadXmlString(property["#text"]);
        } else if (property["@_name"] == "artist") {
          songinfo.artist = processBadXmlString(property["#text"]);
        } else if (property["@_name"] == "album") {
          songinfo.album = processBadXmlString(property["#text"]);
        }
      }
    }
  } catch {
    songinfo.title = "Unknown Title";
    songinfo.artist = "Unknown Artist";
    songinfo.album = "Unknown Album";
  }

  return songinfo;
}

function processBadXmlString(str: string): string {
  let newStr = str;

  while (true) {
    const amp = newStr.indexOf("&#");
    if (amp > 0) {
      const semi = newStr.indexOf(";", amp);
      if (semi > 0) {
        const int = String.fromCharCode(parseInt(newStr.slice(amp + 2, semi)));
        newStr = newStr.replace(newStr.slice(amp, semi + 1), int);
      } else break;
    } else break;
  }

  return newStr;
}