/*
Copyright 2026 Lotus Guild

SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
Please see LICENSE in the repository root for full details.
*/

import { describe, expect, test, vi } from "vitest";
import { BehaviorSubject, of, Subject } from "rxjs";

import { withTestScheduler } from "../utils/test";
import { type UserMediaViewModel } from "../state/media/UserMediaViewModel";
import { type ScreenShareViewModel } from "../state/media/ScreenShareViewModel";
import { type LayoutMode } from "../state/LayoutSwitchViewModel";
import {
  createManualSpotlight,
  type ManualSpotlight,
  overrideSpotlight$,
  pinnedMedia$,
  resolveManualSpotlight,
} from "./lotusSpotlight";
import { parseFocusPayload } from "./lotusFocus";

interface FakeMedia {
  id: string;
  userId: string;
  type: "user";
  local: boolean;
  speaking$: BehaviorSubject<boolean>;
}

function media(
  userId: string,
  deviceId: string,
  speaking = false,
  local = false,
): FakeMedia {
  return {
    id: `${userId}:${deviceId}`,
    userId,
    type: "user",
    local,
    speaking$: new BehaviorSubject(speaking),
  };
}
const asUser = (m: FakeMedia): UserMediaViewModel =>
  m as unknown as UserMediaViewModel;
const screen = { id: "@a:x:d1:screen", userId: "@a:x", type: "screen share" };

const aliceDesk = media("@alice:x", "desk");
const alicePhone = media("@alice:x", "phone", true);
const bob = media("@bob:x", "d");
const all = [aliceDesk, alicePhone, bob];

describe("resolveManualSpotlight (#30)", () => {
  const speaking = (m: FakeMedia): boolean => m.speaking$.value;

  test("null pin resolves to nothing", () => {
    expect(resolveManualSpotlight(null, all, speaking)).toBeUndefined();
  });

  test("prefers the media id when given", () => {
    expect(
      resolveManualSpotlight(
        { userId: "@alice:x", id: "@alice:x:desk" },
        all,
        speaking,
      ),
    ).toBe(aliceDesk);
  });

  test("falls back to the userId when the id is not present", () => {
    expect(
      resolveManualSpotlight(
        { userId: "@alice:x", id: "@alice:x:tablet" },
        all,
        speaking,
      ),
    ).toBe(alicePhone);
  });

  test("userId only: prefers the speaking device, else the first", () => {
    expect(
      resolveManualSpotlight({ userId: "@alice:x", id: null }, all, speaking),
    ).toBe(alicePhone);
    expect(
      resolveManualSpotlight(
        { userId: "@alice:x", id: null },
        all,
        () => false,
      ),
    ).toBe(aliceDesk);
  });

  test("absent user resolves to nothing", () => {
    expect(
      resolveManualSpotlight({ userId: "@carol:x", id: null }, all, speaking),
    ).toBeUndefined();
  });
});

describe("pinnedMedia$", () => {
  test("follows the speaking device live for a userId-only pin", () => {
    withTestScheduler(({ expectObservable, schedule }) => {
      const desk = media("@alice:x", "desk", true);
      const phone = media("@alice:x", "phone", false);
      const pin$ = new BehaviorSubject<ManualSpotlight | null>({
        userId: "@alice:x",
        id: null,
      });
      schedule("-a", {
        a: () => {
          desk.speaking$.next(false);
          phone.speaking$.next(true);
        },
      });
      expectObservable(
        pinnedMedia$(pin$, of([asUser(desk), asUser(phone)])),
      ).toBe("dp", { d: desk, p: phone });
    });
  });
});

describe("overrideSpotlight$", () => {
  test("no pin: identical to upstream", () => {
    withTestScheduler(({ expectObservable }) => {
      const result$ = overrideSpotlight$(
        of(asUser(bob)),
        of(null),
        of([]),
        of(undefined),
        of(all.map(asUser)),
      );
      expectObservable(result$.pipe()).toBe("(a|)", {
        a: expect.objectContaining({ spotlight: [bob] }),
      });
    });
  });

  test("pin replaces the auto speaker without a screenshare", () => {
    withTestScheduler(({ expectObservable }) => {
      const result$ = overrideSpotlight$(
        of(asUser(bob)),
        of({ userId: "@alice:x", id: "@alice:x:desk" }),
        of([]),
        of(undefined),
        of(all.map(asUser)),
      );
      expectObservable(result$).toBe("(a|)", {
        a: expect.objectContaining({ spotlight: [aliceDesk] }),
      });
    });
  });

  test("#29: PiP keeps the auto speaker when a third party is pinned", () => {
    withTestScheduler(({ expectObservable }) => {
      let pip$;
      overrideSpotlight$(
        of(asUser(bob)),
        of({ userId: "@alice:x", id: null }),
        of([screen as unknown as ScreenShareViewModel]),
        of(undefined),
        of(all.map(asUser)),
      ).subscribe((r) => {
        expect(r.spotlight).toEqual([screen, alicePhone]);
        pip$ = r.pip$;
      });
      expectObservable(pip$!).toBe("(b|)", { b: bob });
    });
  });

  test("#29: PiP is blanked only when the auto speaker is the pinned one", () => {
    withTestScheduler(({ expectObservable }) => {
      let pip$;
      overrideSpotlight$(
        of(asUser(alicePhone)),
        of({ userId: "@alice:x", id: null }),
        of([screen as unknown as ScreenShareViewModel]),
        of(undefined),
        of(all.map(asUser)),
      ).subscribe((r) => {
        pip$ = r.pip$;
      });
      expectObservable(pip$!).toBe("(u|)", { u: undefined });
    });
  });
});

describe("createManualSpotlight (#3 / #16)", () => {
  function setup(initialLayout: LayoutMode = "grid") {
    const pin$ = new BehaviorSubject<ManualSpotlight | null>(null);
    const layout$ = new BehaviorSubject<LayoutMode>(initialLayout);
    const setLayout = vi.fn((m: LayoutMode) => layout$.next(m));
    const userMedia$ = new BehaviorSubject<{ userId: string }[]>([
      { userId: "@alice:x" },
      { userId: "@bob:x" },
    ]);
    const leave$ = new Subject<void>();
    const ctl = createManualSpotlight(
      pin$,
      userMedia$,
      leave$,
      { layout$, setLayout },
      5000,
    );
    const sub = ctl.effects$.subscribe();
    return { pin$, layout$, setLayout, userMedia$, leave$, ctl, sub };
  }

  test("pinning forces spotlight and clearing restores the displaced mode", () => {
    const { ctl, layout$, setLayout, pin$ } = setup("grid");
    ctl.setManualSpotlight({ userId: "@alice:x", id: null });
    expect(pin$.value).toEqual({ userId: "@alice:x", id: null });
    expect(setLayout).toHaveBeenLastCalledWith("spotlight");
    // Re-pinning someone else does not touch the layout again.
    ctl.setManualSpotlight({ userId: "@bob:x", id: null });
    expect(setLayout).toHaveBeenCalledTimes(1);
    ctl.setManualSpotlight(null);
    expect(layout$.value).toBe("grid");
    expect(setLayout).toHaveBeenCalledTimes(2);
  });

  test("already in spotlight: nothing is forced or restored", () => {
    const { ctl, setLayout } = setup("spotlight");
    ctl.setManualSpotlight({ userId: "@alice:x", id: null });
    ctl.setManualSpotlight(null);
    expect(setLayout).not.toHaveBeenCalled();
  });

  test("does not clobber a layout the user chose while pinned", () => {
    const { ctl, layout$, setLayout } = setup("grid");
    ctl.setManualSpotlight({ userId: "@alice:x", id: null });
    layout$.next("grid"); // user switched back manually
    ctl.setManualSpotlight(null);
    expect(setLayout).toHaveBeenCalledTimes(1);
  });

  test("#16: pin is cleared when the user is gone for 5 s, not on a blip", () => {
    vi.useFakeTimers();
    try {
      const { ctl, pin$, userMedia$, layout$ } = setup("grid");
      ctl.setManualSpotlight({ userId: "@alice:x", id: null });
      // Transient absence: back within the window.
      userMedia$.next([{ userId: "@bob:x" }]);
      vi.advanceTimersByTime(2000);
      userMedia$.next([{ userId: "@alice:x" }, { userId: "@bob:x" }]);
      vi.advanceTimersByTime(6000);
      expect(pin$.value).not.toBeNull();
      // Real leave.
      userMedia$.next([{ userId: "@bob:x" }]);
      vi.advanceTimersByTime(4999);
      expect(pin$.value).not.toBeNull();
      vi.advanceTimersByTime(1);
      expect(pin$.value).toBeNull();
      expect(layout$.value).toBe("grid");
    } finally {
      vi.useRealTimers();
    }
  });

  test("#16: pin is cleared on leave$", () => {
    const { ctl, pin$, leave$, layout$ } = setup("grid");
    ctl.setManualSpotlight({ userId: "@alice:x", id: null });
    expect(layout$.value).toBe("spotlight");
    leave$.next();
    expect(pin$.value).toBeNull();
    expect(layout$.value).toBe("grid");
  });
});

describe("parseFocusPayload (#30)", () => {
  test("omitted userId leaves the pin alone", () => {
    expect(parseFocusPayload(undefined)).toBeUndefined();
    expect(parseFocusPayload({})).toBeUndefined();
    expect(parseFocusPayload({ id: "@a:x:d" })).toBeUndefined();
  });
  test("null / non-string userId clears", () => {
    expect(parseFocusPayload({ userId: null })).toBeNull();
    expect(parseFocusPayload({ userId: 42 })).toBeNull();
  });
  test("userId with and without id", () => {
    expect(parseFocusPayload({ userId: "@a:x" })).toEqual({
      userId: "@a:x",
      id: null,
    });
    expect(parseFocusPayload({ userId: "@a:x", id: "@a:x:d" })).toEqual({
      userId: "@a:x",
      id: "@a:x:d",
    });
    expect(parseFocusPayload({ userId: "@a:x", id: 7 })).toEqual({
      userId: "@a:x",
      id: null,
    });
  });
});