import { afterEach, beforeAll, describe, expect, it, vi } from 'vitest';
import { CreateAssetCommand, SetAssetPropertyCommand } from '../../src/core/commands/assetCommands';
import { AddFrameCommand, SetFrameCollisionCommand } from '../../src/core/commands/frameCommands';
import { AddTilePictureCommand } from '../../src/core/commands/tileCommands';
import { PaintTilesCommand } from '../../src/core/commands/tilemapCommands';
import type { TextureAsset, TilemapAsset } from '../../src/core/model/Asset';
import { liveLayers } from '../../src/core/model/liveTilemap';
import { findAsset } from '../../src/core/model/Project';
import { TILE_KIND_KEY, TILE_SOLID_KEY } from '../../src/core/model/tile';
import {
  layerTiles,
  TILEMAP_COLUMNS_KEY,
  TILEMAP_ROWS_KEY,
  TILEMAP_TILE_KEY,
} from '../../src/core/model/tilemap';
import { solidPolygons, solidRects } from '../../src/core/model/tilemapCollision';
import { cellsChanged, cellsVersion, KeyedMemo } from '../../src/core/model/tilemapMemo';
import { loadPhysics } from '../../src/runtime/physics/engine';
import { Solids } from '../../src/runtime/systems/solids';
import { makeSpriteScene, place, startWorld } from '../helpers';

beforeAll(async () => {
  await loadPhysics();
});

afterEach(() => {
  vi.restoreAllMocks();
});

const TRIANGLE = [
  { x: 0, y: 0 },
  { x: 32, y: 0 },
  { x: 0, y: 32 },
];

/**
 * A 4 × 4 map of 32 px cells with two tiles: `box` blocks as a box, `cut` with a triangle drawn on
 * its picture. Both lie on the one layer, `box` along the top row and `cut` at (1,2).
 */
function map() {
  const f = makeSpriteScene('Thing');
  const texture = new CreateAssetCommand('texture', 'Sheet');
  const box = new CreateAssetCommand('tile', 'Box');
  const cut = new CreateAssetCommand('tile', 'Cut');
  const tilemap = new CreateAssetCommand('tilemap', 'Ground');
  for (const command of [texture, box, cut, tilemap]) f.stack.execute(command);
  const sheet = findAsset(f.project, texture.asset.id) as TextureAsset;
  sheet.file = `${'a'.repeat(64)}.png`;
  sheet.width = 32;
  sheet.height = 32;
  const frame = new AddFrameCommand(texture.asset.id, { x: 0, y: 0, w: 32, h: 32 });
  f.stack.execute(frame);
  f.stack.execute(new AddTilePictureCommand(cut.asset.id, frame.frameId));
  f.stack.execute(new SetFrameCollisionCommand(texture.asset.id, frame.frameId, [TRIANGLE]));
  for (const tile of [box, cut]) {
    f.stack.execute(new SetAssetPropertyCommand(tile.asset.id, TILE_SOLID_KEY, true));
    f.stack.execute(new SetAssetPropertyCommand(tile.asset.id, TILE_KIND_KEY, 'none'));
  }
  for (const [key, value] of [
    [TILEMAP_COLUMNS_KEY, 4],
    [TILEMAP_ROWS_KEY, 4],
    [TILEMAP_TILE_KEY, 32],
  ] as const)
    f.stack.execute(new SetAssetPropertyCommand(tilemap.asset.id, key, value));
  const mapId = place(f, tilemap.asset.id, { x: 0, y: 0 });
  const asset = findAsset(f.project, tilemap.asset.id) as TilemapAsset;
  const layer = asset.layers[0]!;
  const top = [0, 1, 2, 3].map((x) => ({ x, y: 0, tileId: box.asset.id }));
  f.stack.execute(new PaintTilesCommand(asset.id, layer.id, [...top, { x: 1, y: 2, tileId: cut.asset.id }]));
  return {
    ...f,
    mapId,
    asset,
    layer,
    boxId: box.asset.id,
    cutId: cut.asset.id,
    textureId: texture.asset.id,
    frameId: frame.frameId,
    props: asset.props,
  };
}

describe('what a tilemap works out is remembered while its content stays', () => {
  it('a version stays while the cells hold the same, and changes when one is painted in place', () => {
    const cells: Record<string, string> = { '0,0': 'a', '1,0': 'b' };
    const paint = (key: string, tileId: string) => {
      if (tileId) cells[key] = tileId;
      else delete cells[key];
      cellsChanged(cells);
    };
    const first = cellsVersion(cells);
    expect(cellsVersion(cells)).toBe(first);
    paint('2,0', 'a');
    const added = cellsVersion(cells);
    expect(added).not.toBe(first);
    paint('2,0', 'b');
    const changed = cellsVersion(cells);
    expect(changed).not.toBe(added);
    paint('0,0', '');
    expect(cellsVersion(cells)).not.toBe(changed);
  });

  it('cells are compared only when their painter says so, and keep their version when nothing differs', () => {
    const cells: Record<string, string> = { '0,0': 'a', '1,0': 'b' };
    const first = cellsVersion(cells);
    // A stroke that ends where it began: written to, but the same content as before.
    cells['2,0'] = 'a';
    delete cells['2,0'];
    cellsChanged(cells);
    expect(cellsVersion(cells)).toBe(first);
    // Not walked again on every question: a write nobody reported goes unseen until one is.
    cells['2,0'] = 'a';
    expect(cellsVersion(cells)).toBe(first);
    cellsChanged(cells);
    expect(cellsVersion(cells)).not.toBe(first);
  });

  it('a paint command and its undo are each seen at once', () => {
    const m = map();
    expect(solidRects(m.project, m.props, m.asset)).toEqual([{ x: 0, y: 0, w: 4, h: 1 }]);
    m.stack.execute(new PaintTilesCommand(m.asset.id, m.layer.id, [{ x: 0, y: 3, tileId: m.boxId }]));
    expect(solidRects(m.project, m.props, m.asset)).toEqual([
      { x: 0, y: 0, w: 4, h: 1 },
      { x: 0, y: 3, w: 1, h: 1 },
    ]);
    m.stack.undo();
    expect(solidRects(m.project, m.props, m.asset)).toEqual([{ x: 0, y: 0, w: 4, h: 1 }]);
  });

  it('the cache hands out what it made for a key, and forgets the oldest once full', () => {
    const memo = new KeyedMemo<number[]>(2);
    const make = vi.fn(() => [1]);
    const a = memo.get('a', make);
    expect(memo.get('a', make)).toBe(a);
    expect(make).toHaveBeenCalledTimes(1);
    memo.get('b', make);
    memo.get('c', make);
    expect(memo.get('a', make)).not.toBe(a);
    expect(make).toHaveBeenCalledTimes(4);
  });

  it('asking again for an unchanged map hands out the very same tiles and solids', () => {
    const m = map();
    expect(layerTiles(m.project, m.props, m.layer)).toBe(layerTiles(m.project, m.props, m.layer));
    expect(solidRects(m.project, m.props, m.asset)).toBe(solidRects(m.project, m.props, m.asset));
    expect(solidPolygons(m.project, m.props, m.asset)).toBe(solidPolygons(m.project, m.props, m.asset));
  });

  it('a cell painted in place, as a stroke does before it is a command, is seen at once', () => {
    const m = map();
    const rects = solidRects(m.project, m.props, m.asset);
    expect(rects).toEqual([{ x: 0, y: 0, w: 4, h: 1 }]);
    m.layer.cells['0,3'] = m.boxId;
    cellsChanged(m.layer.cells);
    expect(solidRects(m.project, m.props, m.asset)).toEqual([
      { x: 0, y: 0, w: 4, h: 1 },
      { x: 0, y: 3, w: 1, h: 1 },
    ]);
    expect(layerTiles(m.project, m.props, m.layer).map((t) => `${t.x},${t.y}`)).toContain('0,3');
    delete m.layer.cells['1,2'];
    cellsChanged(m.layer.cells);
    expect(solidPolygons(m.project, m.props, m.asset)).toEqual([]);
  });

  it('a tile no longer solid, a new outline and a new kind are each seen at once', () => {
    const m = map();
    const polygons = solidPolygons(m.project, m.props, m.asset);
    expect(polygons).toHaveLength(1);
    const other = [
      { x: 32, y: 0 },
      { x: 32, y: 32 },
      { x: 0, y: 32 },
    ];
    m.stack.execute(new SetFrameCollisionCommand(m.textureId, m.frameId, [other]));
    const turned = solidPolygons(m.project, m.props, m.asset);
    expect(turned).not.toBe(polygons);
    expect(turned[0]!.outline).not.toEqual(polygons[0]!.outline);
    m.stack.execute(new SetAssetPropertyCommand(m.boxId, TILE_SOLID_KEY, false));
    expect(solidRects(m.project, m.props, m.asset)).toEqual([]);
    const before = layerTiles(m.project, m.props, m.layer).find((t) => t.tileId === m.boxId)!;
    m.stack.execute(new SetAssetPropertyCommand(m.boxId, TILE_KIND_KEY, 'floor'));
    const after = layerTiles(m.project, m.props, m.layer).find((t) => t.tileId === m.boxId)!;
    expect(after.quadrants).not.toEqual(before.quadrants);
  });

  it('a run lays the same edits over a layer once, and again when the layer was painted meanwhile', () => {
    const m = map();
    const edits = { [m.layer.id]: { '3,3': m.boxId } };
    const first = liveLayers(m.asset, edits)[0]!;
    expect(liveLayers(m.asset, edits)[0]).toBe(first);
    m.layer.cells['2,3'] = m.boxId;
    cellsChanged(m.layer.cells);
    const painted = liveLayers(m.asset, edits)[0]!;
    expect(painted).not.toBe(first);
    expect(painted.cells['2,3']).toBe(m.boxId);
    expect(painted.cells['3,3']).toBe(m.boxId);
    m.layer.z = 3;
    expect(liveLayers(m.asset, edits)[0]!.z).toBe(3);
  });

  it('the physics works a still map out once, and again once it is moved', () => {
    const m = map();
    const shapesOf = vi.spyOn(Solids.prototype, 'solidShapesOf');
    const s = startWorld(m, { physics: true, collisions: true });
    const mapWorkedOut = () =>
      shapesOf.mock.calls.filter(([, body, within]) => body.objectId === m.mapId && !within).length;
    for (let i = 0; i < 5; i++) s.frame();
    expect(mapWorkedOut()).toBe(1);
    s.world.findByObjectId(m.mapId)!.x += 10;
    s.frame();
    expect(mapWorkedOut()).toBe(2);
    s.frame();
    expect(mapWorkedOut()).toBe(2);
  });
});