export class Router {
  private routes: Record<string, Handler[]> = {};

  public route(route: string) {
    const methods: Record<string, Handler> = {
      get: () => undefined,
      post: () => undefined,
      put: () => undefined,
      delete: () => undefined,
    };
    this.routes[route] = this.routes[route] || [];
    this.routes[route].push((r, c) => {
      switch (r.method) {
        case "GET":
          return methods.get?.(r, c);
        case "POST":
          return methods.post?.(r, c);
        case "PUT":
          return methods.put?.(r, c);
        case "DELETE":
          return methods.delete?.(r, c);
        default:
          return undefined;
      }
    });
    return {
      get(handler: Handler) {
        methods.get = handler;
        return this;
      },
      post(handler: Handler) {
        methods.post = handler;
        return this;
      },
      put(handler: Handler) {
        methods.put = handler;
        return this;
      },
      delete(handler: Handler) {
        methods.delete = handler;
        return this;
      },
    };
  }

  public handle = async (req: Request): Promise<Response> => {
    const url = new URL(req.url);
    const route = url.pathname;
    if (route in this.routes) {
      let res;
      for (const handler of this.routes[route]) {
        res = await handler(req, {
          url,
          state: {},
        });
        if (res) {
          return res;
        }
      }
    }
    return new Response("Not found", { status: 404 });
  };
}

export type Handler = (
  req: Request,
  ctx: Context,
) => Promise<Response | undefined> | Response | undefined;