nEngine/packages/core/test/particle-shader.test.ts

import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { describe, expect, it } from "vitest";
import {
  ContentLoader,
  ContentRegistry,
  particleSchema,
  shaderSchema,
  type ParticleDef,
  type ShaderDef,
} from "../src/index.js";

async function setupLoader(): Promise<{ registry: ContentRegistry; loader: ContentLoader; tmp: string }> {
  const tmp = await mkdtemp(join(tmpdir(), "farm-particle-shader-"));
  await mkdir(join(tmp, "particles"), { recursive: true });
  await mkdir(join(tmp, "shaders"), { recursive: true });
  await writeFile(join(tmp, "particles", "dust.yaml"), "id: dust\nemitRate: 8\ncolors: ['#d7ccc8']\n");
  await writeFile(join(tmp, "shaders", "rain-tint.yaml"), "id: rain-tint\nfilter: grayscale\nparams: { factor: 0.7 }\n");
  const registry = new ContentRegistry();
  const loader = new ContentLoader(registry);
  return { registry, loader, tmp };
}

describe("particle content kind", () => {
  it("loads and validates particle YAML from content/particles/", async () => {
    const { registry, loader, tmp } = await setupLoader();
    try {
      const report = await loader.load(tmp);
      expect(report.ok).toBe(true);
      expect(registry.ids("particle")).toEqual(["dust"]);
      expect(registry.get<ParticleDef>("particle", "dust")).toEqual({ id: "dust", emitRate: 8, colors: ["#d7ccc8"] });
    } finally {
      await rm(tmp, { recursive: true, force: true });
    }
  });

  it("rejects an invalid particle def (bad color, negative speed, strict keys)", () => {
    expect(particleSchema.safeParse({ id: "bad", colors: ["green"] }).success).toBe(false);
    expect(particleSchema.safeParse({ id: "bad", speed: { min: -1, max: 1 } }).success).toBe(false);
    expect(particleSchema.safeParse({ id: "bad", emitRate: 0 }).success).toBe(false);
    expect(particleSchema.safeParse({ id: "bad", extra: true }).success).toBe(false);
  });

  it("accepts an empty (defaults-only) def and a fully-specified def", () => {
    expect(particleSchema.safeParse({ id: "plain" }).success).toBe(true);
    expect(
      particleSchema.safeParse({
        id: "rain",
        emitRate: 24,
        lifetime: { min: 600, max: 1000 },
        speed: { min: 240, max: 360 },
        angle: 90,
        spread: 8,
        gravity: 220,
        size: { min: 1, max: 2 },
        colors: ["#64b5f6"],
        fade: true,
      }).success,
    ).toBe(true);
  });
});

describe("shader content kind", () => {
  it("loads and validates shader YAML from content/shaders/", async () => {
    const { registry, loader, tmp } = await setupLoader();
    try {
      const report = await loader.load(tmp);
      expect(report.ok).toBe(true);
      expect(registry.ids("shader")).toEqual(["rain-tint"]);
      expect(registry.get<ShaderDef>("shader", "rain-tint")).toEqual({
        id: "rain-tint",
        filter: "grayscale",
        params: { factor: 0.7 },
      });
    } finally {
      await rm(tmp, { recursive: true, force: true });
    }
  });

  it("rejects an invalid shader def (unknown filter, strict keys)", () => {
    expect(shaderSchema.safeParse({ id: "bad", filter: "vignette" }).success).toBe(false);
    expect(shaderSchema.safeParse({ id: "bad", filter: "blur", extra: true }).success).toBe(false);
  });

  it("accepts every built-in filter name", () => {
    for (const filter of ["blur", "tint", "grayscale", "sepia", "hue", "brightness"]) {
      expect(shaderSchema.safeParse({ id: "x", filter }).success).toBe(true);
    }
  });
});