interface SemVer {
  readonly major: number;
  readonly minor: number;
  readonly patch: number;
}

function parseSemVer(version: string): SemVer {
  const match = version.match(/^(\d+)\.(\d+)\.(\d+)$/);
  if (!match) throw new Error(`Invalid semver: "${version}"`);
  return {
    major: Number(match[1]),
    minor: Number(match[2]),
    patch: Number(match[3]),
  };
}

function gte(a: SemVer, b: SemVer): boolean {
  if (a.major !== b.major) return a.major > b.major;
  if (a.minor !== b.minor) return a.minor > b.minor;
  return a.patch >= b.patch;
}

export function isApiVersionCompatible(range: string, kernelVersion: string): boolean {
  if (range === "*") return true;

  const kernel = parseSemVer(kernelVersion);

  if (range.startsWith("^")) {
    const min = parseSemVer(range.slice(1));
    if (!gte(kernel, min)) return false;
    if (min.major === 0) {
      return kernel.major === 0 && kernel.minor === min.minor;
    }
    return kernel.major === min.major;
  }

  if (range.startsWith("~")) {
    const min = parseSemVer(range.slice(1));
    if (!gte(kernel, min)) return false;
    return kernel.major === min.major && kernel.minor === min.minor;
  }

  if (range.startsWith(">=")) {
    const min = parseSemVer(range.slice(2));
    return gte(kernel, min);
  }

  const exact = parseSemVer(range);
  return (
    kernel.major === exact.major && kernel.minor === exact.minor && kernel.patch === exact.patch
  );
}
