/**
 * Editing one field of a struct rebuilds the whole bundle – an override is one value per property
 * key, not per field. The question here is what the untouched fields are filled from: an override
 * is sparse and starts out unset, so only the *resolved* value carries the asset's own numbers.
 */
import { beforeEach, describe, expect, it } from 'vitest';
import { CreateAssetCommand, SetAssetPropertyCommand } from '../../src/core/commands/assetCommands';
import { PlaceAssetCommand, SetOverrideCommand } from '../../src/core/commands/sceneObjectCommands';
import { AddStructFieldCommand, AddVariableCommand } from '../../src/core/commands/variableCommands';
import type { PropertyValue } from '../../src/core/model/Properties';
import type { SceneObject } from '../../src/core/model/SceneObject';
import { createEmptyProject, findAsset, findScene } from '../../src/core/model/Project';
import { requirePropDef } from '../../src/core/commands/require';
import { resolveAssetProps, resolveSceneObjectProps } from '../../src/core/properties/resolve';
import { structFieldsOf } from '../../src/editor/inspector/previewHandlers';
import { EditorState } from '../../src/editor/state';

const FIELDS = [
  { key: 'x', kind: 'number' },
  { key: 'y', kind: 'number' },
  { key: 'tag', kind: 'text' },
] as const;

function setup() {
  const state = new EditorState();
  state.loadProject(createEmptyProject('p', 'P'), 1);
  const scene = new CreateAssetCommand('scene', 'Level');
  const behavior = new CreateAssetCommand('behavior', 'B');
  // A rejected command only returns false, so an unasserted setup would let the tests below pass
  // for the wrong reason.
  expect(state.execute(scene)).toBe(true);
  expect(state.execute(behavior)).toBe(true);
  expect(state.execute(new AddVariableCommand(behavior.asset.id, 'piece', 'struct'))).toBe(true);
  for (const field of FIELDS)
    expect(state.execute(new AddStructFieldCommand(behavior.asset.id, 'piece', { ...field }))).toBe(true);
  // The asset's own values: what the inspector shows for an object that overrides nothing.
  expect(
    state.execute(new SetAssetPropertyCommand(behavior.asset.id, 'piece', { x: 3, y: 4, tag: 'T' })),
  ).toBe(true);
  const place = new PlaceAssetCommand(scene.asset.id, behavior.asset.id, { x: 0, y: 0 });
  expect(state.execute(place)).toBe(true);
  return { state, sceneId: scene.asset.id, behaviorId: behavior.asset.id, objectId: place.objectId };
}

describe('editing one field of a struct', () => {
  let f: ReturnType<typeof setup>;
  beforeEach(() => {
    f = setup();
  });

  const asset = () => findAsset(f.state.project, f.behaviorId)!;
  const object = (): SceneObject =>
    findScene(f.state.project, f.sceneId)!.objects.find((o) => o.id === f.objectId)!;
  const structDef = () => {
    const def = requirePropDef(f.state.project, asset(), 'piece');
    if (def.kind !== 'struct') throw new Error('piece is not a struct');
    return def;
  };

  /** The spec `objectSection` builds for an override, resolved value included. */
  const objectHandlers = () =>
    structFieldsOf<SceneObject>({ state: f.state }, structDef(), {
      target: object,
      read: (o) => o.overrides.piece,
      current: (o) => resolveSceneObjectProps(f.state.project, asset(), o).piece,
      write: (o, value) => (o.overrides.piece = value),
      remove: (o) => delete o.overrides.piece,
      commit: (value) => new SetOverrideCommand(f.sceneId, f.objectId, 'piece', value),
    });

  it('fills the untouched fields of a first override from the asset, not from an empty bundle', () => {
    objectHandlers()({ key: 'x', kind: 'number' }).onChange(9);
    expect(object().overrides.piece).toEqual({ x: 9, y: 4, tag: 'T' });
  });

  it('leaves the others alone on a second edit, and undo goes back one field at a time', () => {
    objectHandlers()({ key: 'x', kind: 'number' }).onChange(9);
    objectHandlers()({ key: 'tag', kind: 'text' }).onChange('hi');
    expect(object().overrides.piece).toEqual({ x: 9, y: 4, tag: 'hi' });

    f.state.commands.undo();
    expect(object().overrides.piece).toEqual({ x: 9, y: 4, tag: 'T' });
    f.state.commands.undo();
    expect(object().overrides.piece).toBeUndefined();
  });

  it('builds on the preview while typing, and still undoes to before it', () => {
    const handlers = objectHandlers()({ key: 'x', kind: 'number' });
    handlers.onInput(1);
    handlers.onInput(12);
    handlers.onChange(12);
    expect(object().overrides.piece).toEqual({ x: 12, y: 4, tag: 'T' });

    f.state.commands.undo();
    expect(object().overrides.piece).toBeUndefined();
  });

  it('copies those values in rather than keeping them tied to the asset', () => {
    objectHandlers()({ key: 'x', kind: 'number' }).onChange(9);
    f.state.execute(new SetAssetPropertyCommand(f.behaviorId, 'piece', { x: 3, y: 99, tag: 'T' }));
    // The whole bundle is overridden now, so the asset moving on no longer reaches y.
    expect(resolveSceneObjectProps(f.state.project, asset(), object()).piece).toEqual({
      x: 9,
      y: 4,
      tag: 'T',
    });
  });

  it('takes the stored value where that already is the resolved one – the dense asset bag', () => {
    const handlers = structFieldsOf<{ props: Record<string, PropertyValue> }>(
      { state: f.state },
      structDef(),
      {
        target: () => asset(),
        read: (a) => a.props.piece,
        write: (a, value) => (a.props.piece = value),
        commit: (value) => new SetAssetPropertyCommand(f.behaviorId, 'piece', value),
      },
    );
    handlers({ key: 'y', kind: 'number' }).onChange(8);
    expect(resolveAssetProps(f.state.project, asset()).piece).toEqual({ x: 3, y: 8, tag: 'T' });
  });
});