import { act } from "react";
import { createRoot, type Root } from "react-dom/client";
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import { type HostAuthLanding, readAuthLanding } from "../src/auth-protocol.js";
import { HostApp } from "../src/browser/HostApp.js";
import type { EkklesiaHostConfig } from "../src/host-protocol.js";

/**
 * The host-owned recovery and verification screens (ADR 0038).
 *
 * Everything asserted here is a property of the *host's* browser surface: that an unverified account
 * never reads as authenticated, that a reset token is never persisted or rendered, that a query
 * string can only ever select among Ekklesia's own screens, and that no failure message carries a
 * provider detail. The server-side behaviour these screens sit on top of is proven separately, end
 * to end, in `apps/api/tests/email-verification.integration.ts`.
 */
declare global {
  // eslint-disable-next-line no-var
  var IS_REACT_ACT_ENVIRONMENT: boolean | undefined;
}

const apiBaseUrl = "https://ekklesia.example.test";

let container: HTMLDivElement;
let root: Root;
let consoleError: ReturnType<typeof vi.spyOn>;

beforeEach(() => {
  globalThis.IS_REACT_ACT_ENVIRONMENT = true;
  window.history.replaceState({}, "", "/");
  container = document.createElement("div");
  document.body.append(container);
  root = createRoot(container);
  consoleError = vi.spyOn(console, "error").mockImplementation(() => undefined);
});

afterEach(async () => {
  await act(async () => {
    root.unmount();
  });
  container.remove();
  consoleError.mockRestore();
  localStorage.clear();
  sessionStorage.clear();
});

interface RecordedCall {
  readonly url: string;
  readonly body: string;
}

interface AuthStub {
  /** Status for `/api/auth/sign-in/email`. 403 with `EMAIL_NOT_VERIFIED` is the unverified case. */
  readonly signIn?: () => Response;
  readonly requestPasswordReset?: () => Response;
  readonly resetPassword?: () => Response;
  readonly sendVerificationEmail?: () => Response;
}

interface Platform {
  readonly fetch: typeof fetch;
  readonly calls: RecordedCall[];
}

function platform(stub: AuthStub = {}): Platform {
  const calls: RecordedCall[] = [];
  const implementation = vi.fn(async (input: RequestInfo | URL, init?: RequestInit) => {
    const url = String(input);
    calls.push({ body: String(init?.body ?? ""), url });
    if (url.endsWith("/api/v1/principal")) {
      return Response.json({ kind: "anonymous" });
    }
    if (url.endsWith("/api/auth/sign-in/email")) {
      return (
        stub.signIn?.() ?? Response.json({ code: "INVALID_EMAIL_OR_PASSWORD" }, { status: 401 })
      );
    }
    if (url.endsWith("/api/auth/request-password-reset")) {
      return (
        stub.requestPasswordReset?.() ??
        Response.json({ message: "If this email exists in our system…", status: true })
      );
    }
    if (url.endsWith("/api/auth/reset-password")) {
      return stub.resetPassword?.() ?? Response.json({ status: true });
    }
    if (url.endsWith("/api/auth/send-verification-email")) {
      return stub.sendVerificationEmail?.() ?? Response.json({ status: true });
    }
    return new Response("{}", { status: 404 });
  });
  return { calls, fetch: implementation as unknown as typeof fetch };
}

async function render(config: EkklesiaHostConfig, authLanding?: HostAuthLanding): Promise<void> {
  await act(async () => {
    root.render(<HostApp config={config} {...(authLanding ? { authLanding } : {})} />);
  });
}

function text(): string {
  return container.textContent ?? "";
}

function query(testId: string): Element | null {
  return container.querySelector(`[data-testid="${testId}"]`);
}

async function setInput(testId: string, value: string): Promise<void> {
  const input = query(testId) as HTMLInputElement | null;
  if (!input) {
    throw new Error(`missing input ${testId}`);
  }
  await act(async () => {
    const setter = Object.getOwnPropertyDescriptor(HTMLInputElement.prototype, "value")?.set;
    setter?.call(input, value);
    input.dispatchEvent(new Event("input", { bubbles: true }));
  });
}

async function click(testId: string): Promise<void> {
  const element = query(testId) as HTMLElement | null;
  if (!element) {
    throw new Error(`missing element ${testId}`);
  }
  await act(async () => {
    element.dispatchEvent(new MouseEvent("click", { bubbles: true, cancelable: true }));
    await Promise.resolve();
  });
}

async function submit(hostTestId: string): Promise<void> {
  const form = query(hostTestId)?.querySelector("form");
  if (!form) {
    throw new Error(`missing form in ${hostTestId}`);
  }
  await act(async () => {
    form.dispatchEvent(new Event("submit", { bubbles: true, cancelable: true }));
    await Promise.resolve();
  });
}

describe("emailed-link landing parsing", () => {
  it("recognizes exactly Ekklesia's own two landings", () => {
    expect(readAuthLanding("?ekklesia_auth=verify-email")).toEqual({ kind: "verified" });
    expect(readAuthLanding("?ekklesia_auth=verify-email&error=TOKEN_EXPIRED")).toEqual({
      expired: true,
      kind: "verification-failed",
    });
    expect(readAuthLanding("?ekklesia_auth=verify-email&error=INVALID_TOKEN")).toEqual({
      expired: false,
      kind: "verification-failed",
    });
    expect(readAuthLanding("?ekklesia_auth=reset-password&token=abc123")).toEqual({
      kind: "reset-password",
      token: "abc123",
    });
    expect(readAuthLanding("?ekklesia_auth=reset-password&error=INVALID_TOKEN")).toEqual({
      kind: "reset-link-invalid",
    });
  });

  it("ignores anything that is not one of them, so a query cannot steer the shell", () => {
    for (const search of [
      "",
      "?",
      "?token=abc123",
      "?ekklesia_auth=dashboard",
      "?ekklesia_auth=",
      "?redirect=https://evil.example.test",
      "?ekklesia_auth[]=verify-email",
    ]) {
      expect(readAuthLanding(search)).toBeUndefined();
    }
  });

  it("treats a reset landing with no usable token as an invalid link, never as a token", () => {
    for (const search of [
      "?ekklesia_auth=reset-password",
      "?ekklesia_auth=reset-password&token=",
      "?ekklesia_auth=reset-password&token=has%20space",
      `?ekklesia_auth=reset-password&token=${"a".repeat(257)}`,
    ]) {
      expect(readAuthLanding(search)).toEqual({ kind: "reset-link-invalid" });
    }
  });

  it("names no destination of any kind, so there is nothing to redirect to", () => {
    const landing = readAuthLanding(
      "?ekklesia_auth=verify-email&callbackURL=https://evil.example.test&next=//evil.example.test",
    );

    expect(landing).toEqual({ kind: "verified" });
    expect(JSON.stringify(landing)).not.toContain("evil");
  });
});

describe("unverified sign-in", () => {
  const unverified = (): Response =>
    Response.json({ code: "EMAIL_NOT_VERIFIED", message: "Email not verified" }, { status: 403 });

  it("offers verification instead of a credentials error, and never renders the Dashboard", async () => {
    const stub = platform({ signIn: unverified });
    await render({ apiBaseUrl, fetch: stub.fetch });
    await setInput("login-email", "member@example.org");
    await setInput("login-password", "correct horse battery staple");

    await submit("host-login");

    expect(query("host-verification-required")).not.toBeNull();
    expect(query("host-login")).toBeNull();
    // Not "your password is wrong": it was right. And not the Dashboard either — the server minted
    // no session, so nothing about this state is authenticated.
    expect(text()).not.toContain("Email or password is incorrect");
    expect(text()).toContain("Your password was accepted");
    expect(container.querySelector("aside")).toBeNull();
  });

  it("resends from the address the person just typed, and says nothing about whether it exists", async () => {
    const stub = platform({ signIn: unverified });
    await render({ apiBaseUrl, fetch: stub.fetch });
    await setInput("login-email", "member@example.org");
    await setInput("login-password", "correct horse battery staple");
    await submit("host-login");

    await submit("host-verification-required");

    const resend = stub.calls.find((call) =>
      call.url.endsWith("/api/auth/send-verification-email"),
    );
    expect(resend?.body).toBe(JSON.stringify({ email: "member@example.org" }));
    expect(query("verification-resent")).not.toBeNull();
    // The wording is a conditional, not a confirmation that an account exists.
    expect(text()).toContain("If an unverified Ekklesia account exists");
  });

  it("keeps the password out of every request but the sign-in itself", async () => {
    const stub = platform({ signIn: unverified });
    await render({ apiBaseUrl, fetch: stub.fetch });
    await setInput("login-email", "member@example.org");
    await setInput("login-password", "correct horse battery staple");
    await submit("host-login");
    await submit("host-verification-required");

    for (const call of stub.calls) {
      expect(call.url).not.toContain("correct horse");
      if (!call.url.endsWith("/api/auth/sign-in/email")) {
        expect(call.body).not.toContain("correct horse");
      }
    }
  });
});

describe("forgot password", () => {
  it("reaches the recovery form from the sign-in screen and back again", async () => {
    const stub = platform();
    await render({ apiBaseUrl, fetch: stub.fetch });

    await click("login-forgot-password");
    expect(query("host-forgot-password")).not.toBeNull();

    await click("forgot-cancel");
    expect(query("host-login")).not.toBeNull();
  });

  it("shows one generic completion state, whatever the address", async () => {
    const stub = platform();
    await render({ apiBaseUrl, fetch: stub.fetch });
    await click("login-forgot-password");
    await setInput("forgot-email", "stranger@example.org");

    await submit("host-forgot-password");

    expect(query("host-forgot-password-sent")).not.toBeNull();
    expect(text()).toContain("If an Ekklesia account exists for that address");
    // Nothing on the screen distinguishes an address with an account from one without.
    expect(text()).not.toContain("stranger@example.org");
    expect(text()).not.toContain("No account");
  });

  it("submits once even when the form is submitted repeatedly", async () => {
    let release: (() => void) | undefined;
    const stub = platform({
      requestPasswordReset: () => Response.json({ status: true }),
    });
    const gated = vi.fn(async (input: RequestInfo | URL, init?: RequestInit) => {
      if (String(input).endsWith("/api/auth/request-password-reset")) {
        await new Promise<void>((resolve) => {
          release = resolve;
        });
      }
      return (stub.fetch as unknown as typeof fetch)(input, init);
    });
    await render({ apiBaseUrl, fetch: gated as unknown as typeof fetch });
    await click("login-forgot-password");
    await setInput("forgot-email", "member@example.org");

    await submit("host-forgot-password");
    await submit("host-forgot-password");
    await submit("host-forgot-password");
    release?.();
    await act(async () => {
      await Promise.resolve();
    });

    // Every one of these triggers an email. A duplicate is not merely untidy.
    const requests = stub.calls.filter((call) =>
      call.url.endsWith("/api/auth/request-password-reset"),
    );
    expect(requests).toHaveLength(1);
  });

  it("reports a transport failure without a provider detail or a URL", async () => {
    const stub = platform({
      requestPasswordReset: () => new Response("relay 421 at smtp.example.org", { status: 500 }),
    });
    await render({ apiBaseUrl, fetch: stub.fetch });
    await click("login-forgot-password");
    await setInput("forgot-email", "member@example.org");

    await submit("host-forgot-password");

    expect(text()).toContain("Unable to sign in right now.");
    expect(text()).not.toContain("smtp.example.org");
    expect(text()).not.toContain("421");
    expect(text()).not.toContain(apiBaseUrl);
  });
});

describe("reset password", () => {
  const landing: HostAuthLanding = { kind: "reset-password", token: "reset-token-abc" };

  it("sets a new password and returns cleanly to sign-in", async () => {
    const stub = platform();
    await render({ apiBaseUrl, fetch: stub.fetch }, landing);
    expect(query("host-reset-password")).not.toBeNull();
    await setInput("reset-password", "a brand new passphrase");
    await setInput("reset-password-confirmation", "a brand new passphrase");

    await submit("host-reset-password");

    const request = stub.calls.find((call) => call.url.endsWith("/api/auth/reset-password"));
    expect(JSON.parse(request?.body ?? "{}")).toEqual({
      newPassword: "a brand new passphrase",
      token: "reset-token-abc",
    });
    expect(query("host-reset-password-complete")).not.toBeNull();
    expect(text()).toContain(
      "every existing Ekklesia session for this account has been signed out",
    );

    await click("reset-return-to-sign-in");
    expect(query("host-login")).not.toBeNull();
  });

  it("blocks a mismatched confirmation in the browser, before anything is sent", async () => {
    const stub = platform();
    await render({ apiBaseUrl, fetch: stub.fetch }, landing);
    await setInput("reset-password", "a brand new passphrase");
    await setInput("reset-password-confirmation", "a brand new passphrasf");

    await submit("host-reset-password");

    expect(text()).toContain("The two passwords do not match.");
    expect(stub.calls.some((call) => call.url.endsWith("/api/auth/reset-password"))).toBe(false);
  });

  it("surfaces the server's password policy without inventing one of its own", async () => {
    const stub = platform({
      resetPassword: () => Response.json({ code: "PASSWORD_TOO_SHORT" }, { status: 400 }),
    });
    await render({ apiBaseUrl, fetch: stub.fetch }, landing);
    await setInput("reset-password", "short");
    await setInput("reset-password-confirmation", "short");

    await submit("host-reset-password");

    // The server stays authoritative; the browser only echoes the bounds it was configured with.
    expect(text()).toContain("between 8 and 128 characters");
    const field = query("reset-password") as HTMLInputElement;
    expect(field.minLength).toBe(8);
    expect(field.maxLength).toBe(128);
  });

  it("reports a spent or expired token as a link problem, not a password problem", async () => {
    const stub = platform({
      resetPassword: () => Response.json({ code: "INVALID_TOKEN" }, { status: 400 }),
    });
    await render({ apiBaseUrl, fetch: stub.fetch }, landing);
    await setInput("reset-password", "a brand new passphrase");
    await setInput("reset-password-confirmation", "a brand new passphrase");

    await submit("host-reset-password");

    expect(text()).toContain("This password reset link is no longer valid");
  });

  it("never persists the token, and never renders it", async () => {
    const stub = platform();
    await render({ apiBaseUrl, fetch: stub.fetch }, landing);
    await setInput("reset-password", "a brand new passphrase");
    await setInput("reset-password-confirmation", "a brand new passphrase");
    await submit("host-reset-password");

    // A reset token is a bearer credential for one account. It lives in React state for the life of
    // the form and nowhere else.
    expect(localStorage.length).toBe(0);
    expect(sessionStorage.length).toBe(0);
    expect(text()).not.toContain("reset-token-abc");
    expect(container.innerHTML).not.toContain("reset-token-abc");
    expect(window.location.search).toBe("");
    for (const call of stub.calls) {
      expect(call.url).not.toContain("reset-token-abc");
    }
  });

  it("shows a dead-end-free screen for an invalid reset link", async () => {
    await render({ apiBaseUrl, fetch: platform().fetch }, { kind: "reset-link-invalid" });

    expect(query("host-reset-link-invalid")).not.toBeNull();
    expect(text()).toContain("Password reset links last one hour and can be used once");
    await click("reset-invalid-continue");
    expect(query("host-login")).not.toBeNull();
  });
});

describe("verification landing", () => {
  it("confirms success and offers sign-in, without pretending to be signed in", async () => {
    await render({ apiBaseUrl, fetch: platform().fetch }, { kind: "verified" });

    expect(query("host-verification-succeeded")).not.toBeNull();
    expect(text()).toContain("This address is confirmed");
    // Following an emailed link mints no session, so the Dashboard must not appear.
    expect(container.querySelector("aside")).toBeNull();
    await click("verified-continue");
    expect(query("host-login")).not.toBeNull();
  });

  it("says an expired link has expired, which is the actionable version", async () => {
    await render(
      { apiBaseUrl, fetch: platform().fetch },
      { expired: true, kind: "verification-failed" },
    );

    expect(query("host-verification-failed")).not.toBeNull();
    expect(text()).toContain("This link has expired");
    expect(text()).toContain("Ekklesia will send a new one");
  });

  it("says an unusable link is invalid rather than guessing that it expired", async () => {
    await render(
      { apiBaseUrl, fetch: platform().fetch },
      { expired: false, kind: "verification-failed" },
    );

    expect(text()).toContain("This link is not valid");
    expect(text()).not.toContain("has expired");
  });

  it("still renders the Dashboard for someone who is already signed in", async () => {
    const authenticated = vi.fn(async (input: RequestInfo | URL) => {
      const url = String(input);
      if (url.endsWith("/api/v1/principal")) {
        return Response.json({ kind: "authenticated", userId: "user-1" });
      }
      if (url.endsWith("/api/v1/dashboard/navigation")) {
        return Response.json({ groups: [], ungrouped: [] });
      }
      return new Response("{}", { status: 404 });
    });

    await render(
      { apiBaseUrl, fetch: authenticated as unknown as typeof fetch },
      { kind: "verified" },
    );

    // The principal is still what decides. A landing parameter never promotes anyone.
    expect(query("host-verification-succeeded")).toBeNull();
    expect(query("host-login")).toBeNull();
  });
});