```ts
function parseSemver(version: string): { major: number; minor: number; patch: number; prerelease: string | null; build: string | null } {
    const semVerRegex = /^v?(\d+)\.(\d+)\.(\d+)(-\w*)?(+\w*)$/;
    if (!semVerRegex.test(version)) {
        throw new Error(`Invalid semver format: ${version}`);
    }

    const match = version.match(semVerRegex);
    const major = parseInt(match[1], 10);
    const minor = parseInt(match[2], 10);
    const patch = parseInt(match[3], 10);

    const prerelease = match[4] ? match[4].slice(1) : null;
    const build = match[5] && match[5][0] === '+' ? match[5].slice(1) : null;

    return { major, minor, patch, prerelease, build };
}
```