import { spawnSync } from "node:child_process";
import { existsSync, readdirSync, readFileSync } from "node:fs";
import { join } from "node:path";
import { describe, expect, it } from "vitest";
import { ROOT } from "../lib/common.ts";
import { readdirScenes, type Scene } from "./runner.ts";

describe("README demo scenes", () => {
	it("executes the CLI entrypoint instead of silently skipping it", () => {
		const result = spawnSync(
			process.execPath,
			[join(ROOT, "scripts/demo/runner.ts"), "missing-demo-entrypoint-probe"],
			{ cwd: ROOT, encoding: "utf8", timeout: 10_000 },
		);
		expect(result.error).toBeUndefined();
		expect(result.status).toBe(1);
		expect(result.stderr).toContain("FAIL missing-demo-entrypoint-probe:");
		expect(result.stderr).toContain("no demo/scene.json");
	});

	it("every scene is well-formed and its recordings are committed", () => {
		for (const name of readdirScenes()) {
			const dir = join(ROOT, "extensions", name);
			const scene = JSON.parse(
				readFileSync(join(dir, "demo", "scene.json"), "utf8"),
			) as Scene;
			expect(scene.title, name).toBeTruthy();
			expect(scene.extensions[0], `${name}: protagonist first`).toBe(name);
			expect(scene.steps.length, name).toBeGreaterThan(0);
			expect(
				scene.steps.some((step) => step.expect),
				`${name}: at least one expect`,
			).toBe(true);
			for (const step of scene.steps) {
				if (step.expect) {
					expect(() => new RegExp(step.expect ?? "", "u")).not.toThrow();
					expect(
						step.hold ?? 6,
						`${name}: reading pause`,
					).toBeGreaterThanOrEqual(6);
				}
				if (step.hold !== undefined)
					expect(
						step.hold,
						`${name}: pause fits renderer idle limit`,
					).toBeLessThanOrEqual(60);
			}
			expect(
				existsSync(join(dir, "demo", "SCENE.md")),
				`${name}: SCENE.md`,
			).toBe(true);
			expect(
				existsSync(join(dir, "assets", "demo.cast")),
				`${name}: cast`,
			).toBe(true);
			expect(existsSync(join(dir, "assets", "demo.gif")), `${name}: gif`).toBe(
				true,
			);
			expect(
				readFileSync(join(dir, "README.md"), "utf8"),
				`${name}: README embeds the demo`,
			).toContain("assets/demo.gif");
		}
	});

	it("no README embeds a demo without a scene behind it", () => {
		const root = join(ROOT, "extensions");
		const scenes = new Set(readdirScenes());
		for (const name of readdirSync(root)) {
			const readme = join(root, name, "README.md");
			if (!existsSync(readme) || scenes.has(name)) continue;
			expect(
				readFileSync(readme, "utf8"),
				`${name}: demo.gif without demo/scene.json`,
			).not.toContain("demo.gif");
			expect(
				existsSync(join(root, name, "assets", "demo.gif")),
				`${name}: orphan assets/demo.gif`,
			).toBe(false);
		}
	});
});