import { readFileSync } from "node:fs";
import { describe, expect, it } from "vitest";

// A tab names the account it was built for, and the server refuses a request from a tab showing
// another one than the cookie's. Spelled on both sides, so nothing but this test notices a rename:
// the server would see no header, and a tab left showing the previous account would act as the new
// one without a word.
const read = (path: string) => readFileSync(new URL(path, import.meta.url), "utf-8");
const AUTH = read("../../../../backend/app/auth.py");
const ROUTES = read("../../../../backend/app/routes/auth.py");
const CORE = read("./core.ts");
const CONNECT = read("../googleConnect.ts");
const ENTRY = read("../entryUrl.ts");

describe("the account a tab was built for", () => {
  it("is the header the server checks", () => {
    const backend = /^EXPECTED_ACCOUNT_HEADER = "([^"]+)"$/m.exec(AUTH)?.[1];
    const frontend = /^const EXPECTED_ACCOUNT_HEADER = "([^"]+)";$/m.exec(CORE)?.[1];
    expect(backend).toBeTruthy();
    expect(backend).toBe(frontend?.toLowerCase());
  });

  it("rides a Google connect as the query parameter the route reads", () => {
    // A navigation carries no headers; a rename on one side would leave the connect unchecked.
    expect(CONNECT).toMatch(/params\.set\("expect", account\)/);
    expect(ROUTES).toMatch(/^ {4}expect: str \| None = None,$/m);
  });

  it("lands a refused navigation where the reloaded tab says why", () => {
    const landing = /^ACCOUNT_CHANGED_LANDING = "\/\?([^"]+)"$/m.exec(ROUTES)?.[1];
    const flag = /^export const ACCOUNT_CHANGED_FLAG = "([^"]+)";$/m.exec(ENTRY)?.[1];
    expect(landing).toBeTruthy();
    expect(landing).toBe(flag);
  });
});