const MIN_NODE_VERSION = "20.18.1";

function parseNodeVersion(version) {
	const [major = "0", minor = "0", patch = "0"] = version.replace(/^v/, "").split(".");
	return {
		major: Number.parseInt(major, 10) || 0,
		minor: Number.parseInt(minor, 10) || 0,
		patch: Number.parseInt(patch, 10) || 0,
	};
}

function compareNodeVersions(left, right) {
	if (left.major !== right.major) return left.major - right.major;
	if (left.minor !== right.minor) return left.minor - right.minor;
	return left.patch - right.patch;
}

function isSupportedNodeVersion(version = process.versions.node) {
	return compareNodeVersions(parseNodeVersion(version), parseNodeVersion(MIN_NODE_VERSION)) >= 0;
}

function getUnsupportedNodeVersionLines(version = process.versions.node) {
	return [
		`feynman requires Node.js ${MIN_NODE_VERSION} or later (detected ${version}).`,
		"Switch to Node 20 with `nvm install 20 && nvm use 20`, or use the standalone installer:",
		"curl -fsSL https://feynman.is/install | bash",
	];
}

if (!isSupportedNodeVersion()) {
	for (const line of getUnsupportedNodeVersionLines()) {
		console.error(line);
	}
	process.exit(1);
}