```typescript
function parseSemver(version: string): { major: number; minor: number; patch: number; prerelease: string | null; build: string | null } {
    const regex = /^v?(\d+)\.(\d+)\.(\d+)(?:-(\w+))?(?:\+(\w+))?$/;

    if (!regex.test(version)) {
        throw new Error(`Invalid version string: ${version}`);
    }

    const [_, major, minor, patch, prerelease = null, build = null] = regex.exec(version)! as RegExpExecArray;

    return {
        major: parseInt(major, 10),
        minor: parseInt(minor, 10),
        patch: parseInt(patch, 10),
        prerelease,
        build
    };
}
```