nEngine/packages/render/test/tiles.test.ts

import { describe, expect, it } from "vitest";
import type { MapDef } from "@nengine/core";
import { TILE_COLORS, UNKNOWN_TILE_COLOR, tileAssetId, tileColor } from "../src/tiles.js";

function map(tiles?: Record<string, string>): MapDef {
  return {
    id: "farm",
    width: 2,
    height: 2,
    tilesetRef: "tiles",
    spawn: { x: 0, y: 0 },
    layers: [{ name: "ground", data: [["grass", "water"], ["grass", "tilled"]] }],
    ...(tiles !== undefined ? { tiles } : {}),
  };
}

describe("tile palette", () => {
  it("maps known tile ids to their colors", () => {
    expect(tileColor("grass")).toBe(TILE_COLORS.grass);
    expect(tileColor("tilled")).toBe(TILE_COLORS.tilled);
    expect(tileColor("water")).toBe(TILE_COLORS.water);
    expect(TILE_COLORS.grass).toBe(0x7cb342);
    expect(TILE_COLORS.tilled).toBe(0x8d6e63);
    expect(TILE_COLORS.water).toBe(0x4fc3f7);
  });

  it("falls back to a neutral color for unknown tile ids", () => {
    expect(tileColor("void")).toBe(UNKNOWN_TILE_COLOR);
    expect(tileColor("")).toBe(UNKNOWN_TILE_COLOR);
  });
});

describe("tileAssetId (D31 map tiles mapping)", () => {
  it("resolves a mapped tile id to its image asset id", () => {
    expect(tileAssetId(map({ grass: "grass-1" }), "grass")).toBe("grass-1");
    expect(tileAssetId(map({ grass: "grass-1" }), "water")).toBeUndefined();
  });

  it("returns undefined when the map has no tiles mapping (palette fallback)", () => {
    expect(tileAssetId(map(), "grass")).toBeUndefined();
  });
});