const DISABLED_ENV_VALUES = new Set(["0", "false", "off", "none", "no", "disabled"]);
const ENABLED_ENV_VALUES = new Set(["1", "true", "on", "yes", "enabled"]);

function normalizeEnvBoolean(raw: string | undefined): string | undefined {
	const normalized = raw?.trim().toLowerCase();
	return normalized || undefined;
}

export function parseOptionalEnvBoolean(raw: string | undefined): boolean | undefined {
	const normalized = normalizeEnvBoolean(raw);
	if (!normalized) return undefined;
	if (DISABLED_ENV_VALUES.has(normalized)) return false;
	if (ENABLED_ENV_VALUES.has(normalized)) return true;
	return undefined;
}

export function parseEnvBoolean(
	raw: string | undefined,
	defaultValue: boolean,
): boolean {
	return parseOptionalEnvBoolean(raw) ?? defaultValue;
}