import { describe, expect, it } from 'vitest';
import { DeleteAssetCommand } from '../../src/core/commands/assetCommands';
import { CompoundCommand } from '../../src/core/commands/CompoundCommand';
import { CreateContainerCommand } from '../../src/core/commands/containerCommands';
import { MoveSceneObjectCommand, RemoveSceneObjectsCommand, SetParentCommand } from '../../src/core/commands/sceneObjectCommands';
import { worldPositionOf } from '../../src/core/graph';
import type { ContainerAsset } from '../../src/core/model/Asset';
import { subtreeRoots, treeOrder } from '../../src/core/model/hierarchy';
import { findAsset, findScene } from '../../src/core/model/Project';
import { makeSpriteScene, place, roundTrip, startWorld } from '../helpers';

/** Three boxes: a at (100,100,z1), b at (10,0) and c at (0,5) parented under b (local (-10,5)). */
function setup() {
  const f = makeSpriteScene();
  const a = place(f, f.spriteId, { x: 100, y: 100, z: 1 });
  const b = place(f, f.spriteId, { x: 10, y: 0 });
  const c = place(f, f.spriteId, { x: 0, y: 5 });
  f.stack.execute(new SetParentCommand(f.sceneId, c, b));
  return { ...f, a, b, c };
}

describe('subtree roots', () => {
  it('drops ids that have a selected ancestor', () => {
    const { sceneOf, a, b, c } = setup();
    expect(subtreeRoots(sceneOf(), [a, b, c])).toEqual([a, b]);
    expect(subtreeRoots(sceneOf(), [c, a])).toEqual([c, a]);
  });
});

describe('CreateContainerCommand', () => {
  it('centres the template on the selection and re-parents the roots, keeping world positions', () => {
    const { project, stack, sceneId, spriteId, a, b, c, sceneOf, object, world } = setup();
    const before = { a: world(a), b: world(b), c: world(c) };
    const command = new CreateContainerCommand(sceneId, [a, b]);
    stack.execute(command);

    // Bounding box of (100,100) and (10,0) → centre (55,50); z is always 0.
    const container = object(command.objectId);
    expect(container.assetId).toBe(command.assetId);
    expect(container.parentId).toBe('');
    expect(container.position).toEqual({ x: 55, y: 50, z: 0 });
    expect(object(a).parentId).toBe(command.objectId);
    expect(object(a).position).toEqual({ x: 45, y: 50, z: 1 });
    expect(object(b).position).toEqual({ x: -45, y: -50, z: 0 });
    expect(object(c).parentId).toBe(b); // descendants keep their local frame
    expect(object(c).position).toEqual({ x: -10, y: 5, z: 0 });
    expect({ a: world(a), b: world(b), c: world(c) }).toEqual(before);

    // The asset holds the same structure with private ids; the members point at it.
    const asset = findAsset(project, command.assetId) as ContainerAsset;
    expect(asset.type).toBe('container');
    expect(asset.objects).toHaveLength(3);
    const template = (id: string) => asset.objects.find((t) => t.id === object(id).templateId)!;
    expect(template(a).position).toEqual({ x: 45, y: 50, z: 1 });
    expect(template(a).parentId).toBe('');
    expect(template(c).parentId).toBe(template(b).id);
    expect(template(c).assetId).toBe(spriteId);
    expect(asset.objects.map((t) => t.id)).not.toContain(a);
    expect(treeOrder(sceneOf()).map((e) => e.object.id)).toEqual([command.objectId, a, b, c]);

    stack.undo();
    expect(sceneOf().objects.map((o) => o.id)).toEqual([a, b, c]);
    expect(object(a).parentId).toBe('');
    expect(object(a).position).toEqual({ x: 100, y: 100, z: 1 });
    expect(object(a).templateId).toBe('');
    expect(project.assets.some((x) => x.id === command.assetId)).toBe(false);
    stack.redo();
    expect(object(a).parentId).toBe(command.objectId);
    expect(world(a)).toEqual(before.a);
  });

  it('places the container below the parent all roots share', () => {
    const f = setup();
    const { stack, sceneId, spriteId, b, c, object, world } = f;
    const d = place(f, spriteId, { x: 30, y: 25 }, b);
    const command = new CreateContainerCommand(sceneId, [c, d]);
    stack.execute(command);
    const container = object(command.objectId);
    expect(container.parentId).toBe(b);
    // World centre of c (0,5) and d (30,25) is (15,15); b is at (10,0) → local (5,15).
    expect(container.position).toEqual({ x: 5, y: 15, z: 0 });
    expect(world(c)).toEqual({ x: 0, y: 5, z: 0 });
    expect(world(d)).toEqual({ x: 30, y: 25, z: 0 });
  });

  it('rejects an empty or unknown selection', () => {
    const { stack, sceneId } = setup();
    expect(() => stack.execute(new CreateContainerCommand(sceneId, []))).toThrow(/at least one/);
    expect(() => stack.execute(new CreateContainerCommand(sceneId, ['nope']))).toThrow(/not found/);
  });
});

describe('placing a container', () => {
  it('instantiates the template with fresh ids below the placed object', () => {
    const f = setup();
    const { project, stack, sceneId, a, b, c, sceneOf, object, world } = f;
    const create = new CreateContainerCommand(sceneId, [a, b]);
    stack.execute(create);
    const placed = place(f, create.assetId, { x: 1000, y: 0 });

    const copies = sceneOf().objects.filter((o) => ![a, b, c, create.objectId].includes(o.id));
    expect(copies).toHaveLength(4); // container + 3 template objects
    const root = object(placed);
    expect(root.assetId).toBe(create.assetId);
    const asset = findAsset(project, create.assetId) as ContainerAsset;
    const copyOf = (id: string) => copies.find((o) => o.templateId === object(id).templateId)!;
    expect(copyOf(a).parentId).toBe(placed);
    expect(world(copyOf(a).id)).toEqual({ x: 1045, y: 50, z: 1 });
    expect(copyOf(c).parentId).toBe(copyOf(b).id);
    expect(world(copyOf(c).id)).toEqual({ x: 945, y: -45, z: 0 });
    expect(new Set(copies.map((o) => o.id)).size).toBe(4);
    expect(asset.objects.map((t) => t.id)).not.toContain(copyOf(a).id);

    stack.undo();
    expect(sceneOf().objects).toHaveLength(4);
    expect(sceneOf().objects.some((o) => o.id === placed)).toBe(false);
  });

  it('survives a save/load round trip', () => {
    const { project, stack, sceneId, a, b } = setup();
    const create = new CreateContainerCommand(sceneId, [a, b]);
    stack.execute(create);
    const loaded = roundTrip(project);
    const asset = findAsset(loaded, create.assetId) as ContainerAsset;
    expect(asset.type).toBe('container');
    expect(asset.objects).toHaveLength(3);
    const scene = findScene(loaded, sceneId)!;
    expect(scene.objects.find((o) => o.id === a)?.templateId).toBe(asset.objects[0]!.id);
    expect(scene.objects.find((o) => o.id === create.objectId)?.assetId).toBe(create.assetId);
  });

  it('deleting an asset removes its template objects from containers too', () => {
    const { project, stack, sceneId, spriteId, a, b, sceneOf } = setup();
    const create = new CreateContainerCommand(sceneId, [a, b]);
    stack.execute(create);
    const asset = () => findAsset(project, create.assetId) as ContainerAsset;
    stack.execute(new DeleteAssetCommand(spriteId));
    expect(asset().objects).toHaveLength(0);
    expect(sceneOf().objects.map((o) => o.id)).toEqual([create.objectId]);
    stack.undo();
    expect(asset().objects).toHaveLength(3);
    expect(sceneOf().objects).toHaveLength(4);
  });

  it('spawns a container with its content at runtime', () => {
    const f = setup();
    const { stack, sceneId, a, b, sceneOf } = f;
    const create = new CreateContainerCommand(sceneId, [a, b]);
    stack.execute(create);
    const { world } = startWorld(f);
    const spawned = world.spawn(create.assetId, { x: 500, y: 500, z: 0 }, null)!;
    expect(spawned.type).toBe('container');
    const children = world.entities.filter((e) => e.parent === spawned);
    expect(children).toHaveLength(2);
    const grandchild = world.entities.find((e) => e.parent && children.includes(e.parent))!;
    expect(worldPositionOf(children.find((e) => e.z === 1)!)).toEqual({ x: 545, y: 550, z: 1 });
    expect(worldPositionOf(grandchild)).toEqual({ x: 445, y: 455, z: 0 });
    expect(world.syncToModel()).toBe(true);
    expect(sceneOf().objects).toHaveLength(8);
  });
});

describe('multi-selection commands', () => {
  it('removes several subtrees as one step, covering nested ids', () => {
    const { stack, sceneId, a, b, c, sceneOf, object } = setup();
    stack.execute(new RemoveSceneObjectsCommand(sceneId, [b, c, a]));
    expect(sceneOf().objects).toHaveLength(0);
    stack.undo();
    expect(sceneOf().objects.map((o) => o.id)).toEqual([a, b, c]);
    expect(object(c).parentId).toBe(b);
  });

  it('a compound move rolls back entirely when one part fails', () => {
    const { stack, sceneId, a, object } = setup();
    const compound = new CompoundCommand('Move objects', [
      new MoveSceneObjectCommand(sceneId, a, { x: 1, y: 2, z: 3 }),
      new MoveSceneObjectCommand(sceneId, 'missing', { x: 0, y: 0, z: 0 }),
    ]);
    expect(() => stack.execute(compound)).toThrow(/not found/);
    expect(object(a).position).toEqual({ x: 100, y: 100, z: 1 });
    expect(stack.canUndo).toBe(true); // the earlier commands of setup()
  });
});