import {
  applyExternalViewSnapshot,
  applySnapshotToControls,
  DEFAULT_DIRECTOR_VIEW_SNAPSHOT,
  getViewportGizmoHitButtonStyle,
  getViewportSnapshotFromGizmoDirection,
  shouldRenderViewportGrid,
} from "./DirectorCanvas";
import { createDefaultDirectorProject } from "../store/directorStore";
import { getCameraViewSnapshotFromShot } from "../schema/cameraGeometry";
import { PerspectiveCamera, Vector3 } from "three";

function expectTupleToBeCloseTo(
  received: [number, number, number],
  expected: [number, number, number]
) {
  received.forEach((value, index) => {
    expect(value).toBeCloseTo(expected[index], 5);
  });
}

it("keeps the viewport grid visible when there is no panorama background", () => {
  expect(shouldRenderViewportGrid(false, false)).toBe(true);
});

it("flushes leftover orbit inertia before writing the reset view back", () => {
  const dampingStateDuringUpdate: boolean[] = [];
  const controls = {
    enableDamping: true,
    target: new Vector3(9, 9, 9),
    update: () => dampingStateDuringUpdate.push(controls.enableDamping),
  };
  const camera = new PerspectiveCamera();

  applySnapshotToControls(controls, camera, DEFAULT_DIRECTOR_VIEW_SNAPSHOT);

  // 两次 update 都在「阻尼关闭」状态下跑：第一次结算残余惯性，第二次稳在新视角上。
  // 如果带着残余惯性直接写回，画布还在滑行时点重置视角就会被继续推走（表现为重置无效）。
  expect(dampingStateDuringUpdate).toEqual([false, false]);
  // 用完把阻尼恢复原状
  expect(controls.enableDamping).toBe(true);
  expect(controls.target.toArray()).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.target);
  expect(camera.fov).toBe(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.fov);
  expect(camera.position.toArray()).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.position);
});

it("writes an external view change on the spot instead of deferring it to the next render", () => {
  // 机位视角下没有 OrbitControls：写不进去，交给切回导演视角时的副作用补写
  expect(applyExternalViewSnapshot(null, DEFAULT_DIRECTOR_VIEW_SNAPSHOT)).toBe(false);

  const dampingStateDuringUpdate: boolean[] = [];
  const controls = {
    enableDamping: true,
    target: new Vector3(9, 9, 9),
    object: new PerspectiveCamera(),
    update: () => dampingStateDuringUpdate.push(controls.enableDamping),
  };

  expect(applyExternalViewSnapshot(controls, DEFAULT_DIRECTOR_VIEW_SNAPSHOT)).toBe(true);

  // 当场就把残余惯性结算掉并落到目标视角（惯性滑行中点重置视角不会再被推走）
  expect(dampingStateDuringUpdate).toEqual([false, false]);
  expect(controls.target.toArray()).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.target);
  expect(controls.object.position.toArray()).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.position);
  expect(controls.enableDamping).toBe(true);
});

it("keeps the viewport grid visible when a panorama background is active", () => {
  expect(shouldRenderViewportGrid(true, false)).toBe(true);
});

it("keeps the viewport grid visible when snap to grid is enabled during a panorama background", () => {
  expect(shouldRenderViewportGrid(true, true)).toBe(true);
});

it("starts the director and default camera view from a centered front composition", () => {
  const defaultCamera = createDefaultDirectorProject().cameras[0];

  expect(DEFAULT_DIRECTOR_VIEW_SNAPSHOT).toEqual({
    fov: 50,
    position: [0, 1.55, 5.4],
    target: [0, 1.05, 0],
  });
  const defaultCameraView = getCameraViewSnapshotFromShot(defaultCamera);

  expect(defaultCameraView.fov).toBe(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.fov);
  expectTupleToBeCloseTo(defaultCameraView.position, defaultCamera.transform.position);
  expect(defaultCameraView.target).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.target);
  expect(defaultCamera.transform.position[0]).toBe(0);
  expect(defaultCamera.transform.position[1]).toBeGreaterThan(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.target[1]);
});

it("keeps the current orbit distance when native gizmo axis clicks switch viewport direction", () => {
  const snapshot = getViewportSnapshotFromGizmoDirection(
    DEFAULT_DIRECTOR_VIEW_SNAPSHOT,
    new Vector3(1, 0, 0)
  );

  expect(snapshot.fov).toBe(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.fov);
  expect(snapshot.target).toEqual(DEFAULT_DIRECTOR_VIEW_SNAPSHOT.target);
  expectTupleToBeCloseTo(snapshot.position, [5.423099, 1.05, 0]);
});

it("positions the transparent native gizmo hit target over the visible X axis head", () => {
  const style = getViewportGizmoHitButtonStyle(DEFAULT_DIRECTOR_VIEW_SNAPSHOT, [1, 0, 0]);

  // 命中框以 .viewport-gizmo-overlay 的 80px 图层为基准（见 index.css 契约测试）：
  // 中心 40px，X 轴正向落在屏幕半径 25px 处，15px 命中框需回退半个身位。
  expect(style.left).toBe("57.5px");
  expect(style.top).toBe("32.5px");
  expect(style.zIndex).toBe(100);
});