import { act, render } from "@testing-library/react";
import { isKnownSoftwareWebGL } from "@/lib/device";
import HeroFieldScene from "./HeroFieldScene";

/*
 * O componente que monta a cena: cria o renderizador do Three.js (sem React Three Fiber), põe o canvas na página,
 * liga a batida só com o hero à vista e solta tudo ao sair. A cena nasce em tarefas separadas (renderizador,
 * compilação do shader, primeiro quadro): os testes deixam essas tarefas correrem com `mount`. O WebGL do jsdom não
 * existe: o renderizador é um dublê.
 */

type RendererOptions = {
  alpha?: boolean;
  antialias?: boolean;
  powerPreference?: string;
};
const mockRenderers: MockRenderer[] = [];
let mockFailToCreate = false;
/** O nome do renderizador que o contexto de teste conta (WEBGL_debug_renderer_info); `null` = a extensão não existe. */
let mockRendererName: string | null = null;
/** Quando o teste quer segurar a compilação do shader: a promessa que `compileAsync` devolve. */
let mockCompile: () => Promise<unknown> = () => Promise.resolve();

class MockRenderer {
  domElement = document.createElement("canvas");
  pixelRatio = 1;
  options: RendererOptions;
  render = jest.fn();
  compileAsync = jest.fn(() => mockCompile());
  dispose = jest.fn();
  forceContextLoss = jest.fn();
  setSize = jest.fn();
  setPixelRatio = (value: number) => {
    this.pixelRatio = value;
  };
  getPixelRatio = () => this.pixelRatio;
  getContext = () => ({
    getExtension: (name: string) =>
      name === "WEBGL_debug_renderer_info" && mockRendererName !== null
        ? { UNMASKED_RENDERER_WEBGL: 37446 }
        : null,
    getParameter: (parameter: number) =>
      parameter === 37446 ? mockRendererName : null,
  });
  constructor(options: RendererOptions) {
    if (mockFailToCreate) throw new Error("sem WebGL");
    this.options = options;
    mockRenderers.push(this);
  }
}

// a classe é criada só quando a cena pede o renderizador (o mock é içado antes da declaração dela)
jest.mock("three", () => ({
  ...jest.requireActual("three"),
  WebGLRenderer: jest.fn(
    (options: RendererOptions) => new MockRenderer(options),
  ),
}));

const props = () => ({
  progressRef: { current: 0 },
  visible: false,
  onReady: jest.fn(),
  onError: jest.fn(),
});

function setDevicePixelRatio(value: number) {
  Object.defineProperty(window, "devicePixelRatio", {
    configurable: true,
    value,
  });
}

beforeEach(() => {
  jest.useFakeTimers();
  mockRenderers.length = 0;
  mockFailToCreate = false;
  mockRendererName = null;
  mockCompile = () => Promise.resolve();
  setDevicePixelRatio(1);
});

afterEach(() => {
  jest.useRealTimers();
});

/** Deixa as tarefas da montagem correrem (renderizador, compilação do shader, primeiro quadro pedido). */
const buildScene = (ms = 10) =>
  act(async () => {
    await jest.advanceTimersByTimeAsync(ms);
  });

/** Só a tarefa que já estava na fila (as que ela mesma agenda esperam a próxima chamada): um passo da montagem. */
const nextTask = () =>
  act(async () => {
    await jest.runOnlyPendingTimersAsync();
  });

async function mount(ui: React.ReactElement) {
  const result = render(ui);
  await buildScene();
  return result;
}

describe("HeroFieldScene (ambient 3D)", () => {
  it("creates a transparent renderer without antialiasing, on the high-performance GPU, and puts its canvas in the page", async () => {
    const { container } = await mount(<HeroFieldScene {...props()} />);

    expect(mockRenderers).toHaveLength(1);
    expect(mockRenderers[0].options).toMatchObject({
      alpha: true,
      antialias: false,
      powerPreference: "high-performance",
    });
    const canvas = container.querySelector("canvas");
    expect(canvas).toBe(mockRenderers[0].domElement);
    expect(canvas).toHaveAttribute("aria-hidden", "true");
    expect(container.firstElementChild).toHaveAttribute("aria-hidden", "true");
  });

  it.each([
    [0.5, 1],
    [1, 1],
    [1.25, 1.25],
    [2, 1.5],
    [3, 1.5],
  ])(
    "caps the pixel ratio at 1.5 (device %s -> %s)",
    async (device, expected) => {
      setDevicePixelRatio(device);
      await mount(<HeroFieldScene {...props()} />);
      expect(mockRenderers[0].pixelRatio).toBe(expected);
    },
  );

  it("draws on demand: a frame is asked for, never a fixed 60 fps loop, and nothing keeps running once settled", async () => {
    const frames = jest.spyOn(window, "requestAnimationFrame");
    await mount(<HeroFieldScene {...props()} />);
    expect(frames).toHaveBeenCalledTimes(1);

    // a entrada ainda corre: cada quadro pede o seguinte, até assentar (2,6 s de entrada)
    act(() => {
      jest.advanceTimersByTime(5000);
    });
    const settled = frames.mock.calls.length;
    expect(settled).toBeGreaterThan(2);
    expect(settled).toBeLessThan(5000 / 16);

    // hero fora de cena e tudo assentado: nenhum quadro a mais
    act(() => {
      jest.advanceTimersByTime(5000);
    });
    expect(frames.mock.calls.length).toBe(settled);
    expect(mockRenderers[0].render.mock.calls.length).toBeGreaterThan(2);
  });

  it("tells the page it is ready after the second frame", async () => {
    const scene = props();
    await mount(<HeroFieldScene {...scene} />);
    expect(scene.onReady).not.toHaveBeenCalled();

    act(() => {
      jest.advanceTimersByTime(100);
    });

    expect(scene.onReady).toHaveBeenCalledTimes(1);
  });

  it("starts the 30 fps pulse only while the hero is visible, and stops it when it leaves", async () => {
    const frames = jest.spyOn(window, "requestAnimationFrame");
    const scene = props();
    const { rerender } = await mount(
      <HeroFieldScene {...scene} visible={false} />,
    );
    act(() => {
      jest.advanceTimersByTime(6000);
    });
    const hidden = frames.mock.calls.length;
    expect(jest.getTimerCount()).toBe(0);

    rerender(<HeroFieldScene {...scene} visible />);
    act(() => {
      jest.advanceTimersByTime(20); // o quadro que a batida pediu sai
    });
    expect(jest.getTimerCount()).toBe(1); // um setInterval, nenhum segundo laço
    act(() => {
      jest.advanceTimersByTime(980);
    });
    const shown = frames.mock.calls.length - hidden;
    expect(shown).toBeGreaterThan(20);
    expect(shown).toBeLessThanOrEqual(34);

    rerender(<HeroFieldScene {...scene} visible={false} />);
    const stopped = frames.mock.calls.length;
    act(() => {
      jest.advanceTimersByTime(2000);
    });
    expect(frames.mock.calls.length).toBe(stopped);
    expect(jest.getTimerCount()).toBe(0);
  });

  it("releases the context, the canvas and the timers when it unmounts", async () => {
    const scene = props();
    const { container, unmount } = await mount(
      <HeroFieldScene {...scene} visible />,
    );
    expect(container.querySelector("canvas")).not.toBeNull();

    unmount();

    expect(mockRenderers[0].dispose).toHaveBeenCalledTimes(1);
    expect(mockRenderers[0].forceContextLoss).toHaveBeenCalledTimes(1);
    expect(mockRenderers[0].domElement.isConnected).toBe(false);
    expect(jest.getTimerCount()).toBe(0);
    const drawn = mockRenderers[0].render.mock.calls.length;
    act(() => {
      jest.advanceTimersByTime(1000);
    });
    expect(mockRenderers[0].render.mock.calls.length).toBe(drawn);
  });

  it("does not rebuild the scene when the parent passes new callbacks, and calls the newest ones", async () => {
    const first = props();
    const { rerender } = await mount(<HeroFieldScene {...first} />);
    const second = props();
    rerender(
      <HeroFieldScene
        progressRef={first.progressRef}
        visible={false}
        onReady={second.onReady}
        onError={second.onError}
      />,
    );
    expect(mockRenderers).toHaveLength(1);

    act(() => {
      jest.advanceTimersByTime(100);
    });

    expect(first.onReady).not.toHaveBeenCalled();
    expect(second.onReady).toHaveBeenCalledTimes(1);
  });

  it("tells the page and renders nothing but the empty host when WebGL cannot be created", async () => {
    mockFailToCreate = true;
    const scene = props();

    const { container } = await mount(<HeroFieldScene {...scene} />);

    expect(scene.onError).toHaveBeenCalledTimes(1);
    expect(container.querySelector("canvas")).toBeNull();
  });

  it.each([
    [0, 1], // aparelho que não informa a proporção: 1
    [0.5, 1], // nunca abaixo de 1
    [1.25, 1.25],
    [3, 1.5], // nunca acima de 1,5: cada ponto custa fragmentos e o fundo é ambiente
  ])(
    "draws at a pixel ratio of %p -> the renderer gets %p",
    async (device, expected) => {
      setDevicePixelRatio(device);

      await mount(<HeroFieldScene {...props()} />);

      expect(mockRenderers[0].pixelRatio).toBe(expected);
    },
  );

  it("tells the page when the WebGL context is lost after mounting, through the newest callback", async () => {
    const scene = props();
    await mount(<HeroFieldScene {...scene} />);

    act(() => {
      mockRenderers[0].domElement.dispatchEvent(
        new Event("webglcontextlost", { cancelable: true }),
      );
    });

    expect(scene.onError).toHaveBeenCalledTimes(1);
  });

  describe("built in separate tasks (no single long task)", () => {
    it("takes the steps one task at a time: the renderer, the point cloud and the shader compile, then the first frame", async () => {
      let finishCompile = () => {};
      mockCompile = () =>
        new Promise((resolve) => {
          finishCompile = () => resolve(undefined);
        });
      const frames = jest.spyOn(window, "requestAnimationFrame");
      const scene = props();

      render(<HeroFieldScene {...scene} />);
      // nada acontece dentro do commit do React: nem o contexto WebGL
      expect(mockRenderers).toHaveLength(0);

      await nextTask();
      // tarefa 1: só o renderizador (o contexto WebGL); a nuvem de pontos e o shader esperam a vez
      expect(mockRenderers).toHaveLength(1);
      expect(mockRenderers[0].compileAsync).not.toHaveBeenCalled();
      expect(frames).not.toHaveBeenCalled();

      await nextTask();
      // tarefa 2: a nuvem de pontos e o pedido de compilação; o shader compila fora da thread principal e nada foi desenhado
      expect(mockRenderers[0].compileAsync).toHaveBeenCalledTimes(1);
      expect(frames).not.toHaveBeenCalled();
      expect(mockRenderers[0].setSize).not.toHaveBeenCalled();

      finishCompile();
      await act(async () => {
        await Promise.resolve();
      });
      // a compilação acabou, mas o tamanho e o primeiro quadro esperam a própria tarefa
      expect(mockRenderers[0].setSize).not.toHaveBeenCalled();
      expect(frames).not.toHaveBeenCalled();

      await nextTask();
      // tarefa 3: tamanho e o pedido do primeiro quadro, que sai noutra tarefa (requestAnimationFrame)
      expect(mockRenderers[0].setSize).toHaveBeenCalled();
      expect(frames).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].render).not.toHaveBeenCalled();
      await act(async () => {
        await jest.advanceTimersByTimeAsync(20);
      });
      expect(mockRenderers[0].render).toHaveBeenCalled();
    });

    it("compiles the very scene it is going to draw", async () => {
      await mount(<HeroFieldScene {...props()} />);

      const [scene, camera] = mockRenderers[0].compileAsync.mock
        .calls[0] as unknown as [{ isScene: boolean }, { isCamera: boolean }];
      expect(scene.isScene).toBe(true);
      expect(camera.isCamera).toBe(true);
      await act(async () => {
        await jest.advanceTimersByTimeAsync(20);
      });
      expect(mockRenderers[0].render.mock.calls[0][0]).toBe(scene);
    });

    it("creates nothing when it is unmounted before the first task (StrictMode, a quick scroll away)", async () => {
      const scene = props();
      const { unmount } = render(<HeroFieldScene {...scene} />);

      unmount();
      await buildScene();

      expect(mockRenderers).toHaveLength(0);
      expect(scene.onError).not.toHaveBeenCalled();
      expect(jest.getTimerCount()).toBe(0);
    });

    it("frees the context if it is unmounted between the renderer and the point cloud", async () => {
      const { container, unmount } = render(<HeroFieldScene {...props()} />);
      await nextTask();
      expect(mockRenderers).toHaveLength(1);

      unmount();
      await buildScene();

      expect(mockRenderers[0].compileAsync).not.toHaveBeenCalled();
      expect(mockRenderers[0].dispose).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].forceContextLoss).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].domElement.isConnected).toBe(false);
      expect(container.querySelector("canvas")).toBeNull();
    });

    it("releases the context if it is unmounted while the shader compiles", async () => {
      let finishCompile = () => {};
      mockCompile = () =>
        new Promise((resolve) => {
          finishCompile = () => resolve(undefined);
        });
      const frames = jest.spyOn(window, "requestAnimationFrame");
      const { container, unmount } = await mount(
        <HeroFieldScene {...props()} />,
      );
      expect(mockRenderers).toHaveLength(1);

      unmount();
      finishCompile();
      await buildScene();

      expect(mockRenderers[0].dispose).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].forceContextLoss).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].domElement.isConnected).toBe(false);
      expect(container.querySelector("canvas")).toBeNull();
      expect(frames).not.toHaveBeenCalled();
    });

    it("tells the page, and frees the context, when the shader does not compile", async () => {
      mockCompile = () => Promise.reject(new Error("shader inválido"));
      const scene = props();

      const { container } = await mount(<HeroFieldScene {...scene} />);

      expect(scene.onError).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].dispose).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].forceContextLoss).toHaveBeenCalledTimes(1);
      expect(container.querySelector("canvas")).toBeNull();
    });

    it("applies the visibility the page asked for while it was still being built", async () => {
      const frames = jest.spyOn(window, "requestAnimationFrame");
      const scene = props();
      const { rerender } = render(
        <HeroFieldScene {...scene} visible={false} />,
      );
      rerender(<HeroFieldScene {...scene} visible />);

      await buildScene();
      await act(async () => {
        await jest.advanceTimersByTimeAsync(980);
      });

      // a batida de 30 quadros por segundo ligou assim que a cena nasceu
      expect(frames.mock.calls.length).toBeGreaterThan(20);
    });
  });
});

describe("HeroFieldScene: WebGL por software (o teste é o contexto da própria cena)", () => {
  beforeEach(() => sessionStorage.clear());
  afterEach(() => sessionStorage.clear());

  it.each([
    "ANGLE (Google, Vulkan 1.3.0 (SwiftShader Device (Subzero) (0x0000C0DE)), SwiftShader driver)",
    "llvmpipe (LLVM 15.0.7, 256 bits)",
    "ANGLE (Microsoft, Microsoft Basic Render Driver (0x0000008C) Direct3D11 vs_5_0 ps_5_0, D3D11)",
  ])(
    "draws on the CPU (%s): no canvas, the page is told once, the context is freed and the session remembers it",
    async (name) => {
      mockRendererName = name;
      const scene = props();

      const { container } = await mount(<HeroFieldScene {...scene} />);

      // um só contexto: o do teste é o que a cena abriria para desenhar, sem um segundo
      expect(mockRenderers).toHaveLength(1);
      expect(mockRenderers[0].dispose).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].forceContextLoss).toHaveBeenCalledTimes(1);
      expect(mockRenderers[0].compileAsync).not.toHaveBeenCalled();
      expect(container.querySelector("canvas")).toBeNull();
      expect(scene.onError).toHaveBeenCalledTimes(1);
      expect(scene.onReady).not.toHaveBeenCalled();
      expect(isKnownSoftwareWebGL()).toBe(true);
    },
  );

  it("draws on the GPU: the canvas stays and the session is not marked", async () => {
    mockRendererName =
      "ANGLE (NVIDIA, NVIDIA GeForce RTX 3070 Direct3D11 vs_5_0 ps_5_0, D3D11)";
    const scene = props();

    const { container } = await mount(<HeroFieldScene {...scene} />);

    expect(container.querySelector("canvas")).toBe(mockRenderers[0].domElement);
    expect(scene.onError).not.toHaveBeenCalled();
    expect(isKnownSoftwareWebGL()).toBe(false);
  });

  it("does not report an unknown renderer (no debug extension) as software", async () => {
    mockRendererName = null;
    const scene = props();

    await mount(<HeroFieldScene {...scene} />);

    expect(scene.onError).not.toHaveBeenCalled();
    expect(isKnownSoftwareWebGL()).toBe(false);
  });
});