import { Database } from 'bun:sqlite';
import {
  addUser,
  fetchCard,
  fetchLesson,
  fetchLessons,
  fetchResource,
} from './db';

const db = new Database('../db/data.db', { strict: true });
db.exec('PRAGMA journal_mode = WAL;');

Bun.serve({
  fetch(req) {
    const url = new URL(req.url);
    console.log(url.pathname, 'url');
    const user = parseUser(req);
    if (req.method === 'POST' && url.pathname === '/api')
      return handlePost(req, user, url);
    if (req.method === 'GET' && url.pathname.startsWith('/api'))
      return handleGet(req, user, url);
    return serveStatic(url);
  },
});

function parseUser(req: Request): number {
  // console.log(req, 'request');
  return 0;
}

async function serveStatic(url: URL) {
  const filename = url.pathname === '/' ? '/index.html' : url.pathname;
  const headers = { 'Content-type': 'text/html' };
  const opts = { headers };
  try {
    const file = await Bun.file(`../ui/${filename}`).bytes();
    return new Response(file, opts);
  } catch (_) {
    return new Response('404!');
  }
}

async function handleGet(_req: Request, user: number, url: URL) {
  if (url.pathname === '/api/resource') return handleGetExpresion(user, url);
  if (url.pathname === '/api/card') return handleGetCard(user, url);
  if (url.pathname === '/api/lesson') return handleGetLesson(user, url);
  if (url.pathname === '/api/lessons') return handleGetLessons(user, url);
  else return new Response('huh');
}
function handleGetExpresion(user: number, url: URL) {
  const params = new URLSearchParams(url.search);
  const expression = params.get('exp');
  const data = fetchResource(db, expression!);
  return Response.json({ ok: data });
}
type LessonsType = Record<
  number,
  {
    id: number;
    text: string;
    cards: Array<{ text: string; note: string | null; id: number }>;
  }
>;
type LessonsDBType = {
  id: number;
  ltext: string;
  ctext: string;
  cnote: string | null;
  cid: number;
};
function handleGetLesson(user: number, url: URL) {
  const params = new URLSearchParams(url.search);
  const lesson = params.get('lesson');
  const data = fetchLesson(db, Number(lesson!));
  return Response.json({ ok: data });
}
function handleGetCard(user: number, url: URL) {
  const params = new URLSearchParams(url.search);
  const card = params.get('card');
  const data = fetchCard(db, Number(card), user);
  return Response.json({ ok: data });
}
function handleGetLessons(user: number, url: URL) {
  const params = new URLSearchParams(url.search);
  const page = params.get('page') || '0';
  const data: LessonsDBType[] = fetchLessons(db, 20, Number(page)) as any;
  const lessons = data.reduce((acc: LessonsType, item: LessonsDBType) => {
    let cur = acc[item.id] || { id: item.id, text: item.ltext, cards: [] };
    const cards = [
      ...cur.cards,
      { text: item.ctext, note: item.cnote, id: item.cid },
    ];
    const def = { ...cur, cards };
    return { ...acc, [item.id]: def };
  }, {} as LessonsType);
  console.log(lessons, 'lesons');
  return Response.json({ ok: lessons });
}

async function handlePost(req: Request, user: number, url: URL) {
  const data = await req.json();
  if (url.pathname === '/api/user') return handlePostUser(data);
  else return new Response('huh');
}
// https://bun.sh/guides/http/server
type PostUser = { name: string; creds: string };
function handlePostUser(user: PostUser) {
  addUser(db, user.name, user.creds);
  return new Response('ok');
}