// @vitest-environment jsdom
//
// The login card's sub-views (Create an account / Forgot password / Didn't get the email) used to be
// plain React state: clicking one changed nothing in history, so Back popped to whatever entry came
// before the card and the address bar moved while the form on screen did not. They now ride
// useHistorySubview, and this pins the wiring decisions that are specific to THIS card — which modes
// are mirrored, and that Back walks the views. The hook's own mechanics live in
// history.subview.dom.test.ts.
import { describe, it, expect, beforeEach, afterEach } from "vitest";
import { renderHook, act } from "@testing-library/react";

import { useHistorySubview } from "../lib/history";
import { MODE_URL, type Mode } from "./welcomeMode";

const render = (root: Mode = "signin") => renderHook(() => useHistorySubview<Mode>(root, MODE_URL));

// jsdom's history.back() is asynchronous and does not rewind location, so — as in
// history.subview.dom.test.ts — a Back is simulated by landing on the target entry and firing
// popstate. `open()` pushing a REAL entry is asserted separately via history.length.
const popTo = (search: string, state: unknown = null) =>
  act(() => {
    window.history.replaceState(state, "", search || "/");
    window.dispatchEvent(new PopStateEvent("popstate", { state }));
  });

// jsdom keeps one history across a file; land on a clean root entry before each test.
beforeEach(() => window.history.replaceState(null, "", "/"));
afterEach(() => window.history.replaceState(null, "", "/"));

describe("login card mode ↔ URL", () => {
  it("mirrors the three link-reachable views and leaves sign-in as the bare root", () => {
    expect(MODE_URL.encode("signin")).toBeNull();
    expect(MODE_URL.encode("register")).toBe("register");
    expect(MODE_URL.encode("forgot")).toBe("forgot");
    expect(MODE_URL.encode("resend")).toBe("resend");
  });

  it("never mirrors the reset view", () => {
    // Reset is only reachable with the one-time token from the #reset fragment. Mirroring it would
    // hand out a bookmark that opens a password form with no token behind it.
    expect(MODE_URL.encode("reset")).toBeNull();
    expect(MODE_URL.decode("reset")).toBeNull();
  });

  it("decodes only real views, so a hand-typed ?m= falls back to sign-in", () => {
    expect(MODE_URL.decode("register")).toBe("register");
    expect(MODE_URL.decode("")).toBeNull();
    expect(MODE_URL.decode("nonsense")).toBeNull();
  });

  it("opening a view pushes a real history entry, and landing back on the root restores sign-in", () => {
    const { result } = render();
    const entries = window.history.length;
    expect(result.current.view).toBe("signin");

    act(() => result.current.open("forgot"));

    // The whole point: a Back has somewhere to go. Before this the click changed state only.
    expect(window.history.length).toBe(entries + 1);
    expect(result.current.view).toBe("forgot");
    expect(new URLSearchParams(window.location.search).get("m")).toBe("forgot");

    popTo("/");

    expect(result.current.view).toBe("signin");
  });

  it("walks back one view at a time when the user hops between them", () => {
    const { result } = render();
    const entries = window.history.length;
    act(() => result.current.open("register"));
    act(() => result.current.open("forgot"));
    expect(window.history.length).toBe(entries + 2); // one entry per view, not one for the lot

    popTo("/?m=register", { _sub: "register" });
    expect(result.current.view).toBe("register");

    popTo("/");
    expect(result.current.view).toBe("signin");
  });

  it("opens on the reset view when a reset token seeded it, without putting it in the URL", () => {
    const { result } = render("reset");
    expect(result.current.view).toBe("reset");
    expect(window.location.search).toBe("");
  });

  it("restores a bookmarked view from the URL alone", () => {
    window.history.replaceState(null, "", "/?m=resend");
    const { result } = render();
    expect(result.current.view).toBe("resend");
  });
});