import type { AuthOption } from "../../../../wallets/types.js";
import type { WalletId } from "../../../wallet-types.js";
import type { AuthStoredTokenWithCookieReturnType } from "../../core/authentication/types.js";

/**
 * Checks for an auth token and associated metadata in the current URL
 */
export function getUrlToken():
  | {
      walletId?: WalletId;
      authResult?: AuthStoredTokenWithCookieReturnType;
      authProvider?: AuthOption;
      authCookie?: string;
      authFlow?: "connect" | "link";
    }
  | undefined {
  if (typeof document === "undefined") {
    // Not in web
    return undefined;
  }

  // Read params from the standard query string
  const params = new URLSearchParams(window.location.search);

  // Also check for params embedded inside the hash fragment (e.g. #/route?walletId=...)
  // This supports hash-routed apps where params may be placed after the hash path
  let hashParams: URLSearchParams | undefined;
  const hash = window.location.hash || "";
  let cleanHash = hash;
  const hashQueryIndex = hash.indexOf("?");
  if (hashQueryIndex !== -1) {
    hashParams = new URLSearchParams(hash.substring(hashQueryIndex));
    cleanHash = hash.substring(0, hashQueryIndex);
  }

  const walletId = (params.get("walletId") ??
    hashParams?.get("walletId") ??
    undefined) as WalletId | undefined;
  const authResultString =
    params.get("authResult") ?? hashParams?.get("authResult") ?? undefined;
  const authProvider = (params.get("authProvider") ??
    hashParams?.get("authProvider") ??
    undefined) as AuthOption | undefined;
  const authCookie = (params.get("authCookie") ??
    hashParams?.get("authCookie") ??
    undefined) as string | undefined;
  const authFlow = (params.get("authFlow") ??
    hashParams?.get("authFlow") ??
    undefined) as "connect" | "link" | undefined;

  if ((authCookie || authResultString) && walletId) {
    const authResult = (() => {
      if (authResultString) {
        params.delete("authResult");
        hashParams?.delete("authResult");
        return JSON.parse(decodeURIComponent(authResultString));
      }
    })();
    params.delete("walletId");
    params.delete("authProvider");
    params.delete("authCookie");
    params.delete("authFlow");
    hashParams?.delete("walletId");
    hashParams?.delete("authProvider");
    hashParams?.delete("authCookie");
    hashParams?.delete("authFlow");

    const remainingSearch = params.toString();
    const searchString = remainingSearch ? `?${remainingSearch}` : "";

    // Reconstruct hash, preserving the hash path and any remaining non-auth params
    let hashString = cleanHash;
    if (hashParams) {
      const remainingHashParams = hashParams.toString();
      if (remainingHashParams) {
        hashString = `${cleanHash}?${remainingHashParams}`;
      }
    }

    window.history.pushState(
      {},
      "",
      `${window.location.pathname}${searchString}${hashString}`,
    );
    return { authCookie, authFlow, authProvider, authResult, walletId };
  }
  return undefined;
}