```ts
/**
 * Parses a semantic version string into its components.
 *
 * @param version - The semantic version string to parse.
 * @returns An object containing major, minor, patch, prerelease, and build components.
 */
export function parseSemver(version: string): { major: number; minor: number; patch: number; prerelease: string | null; build: string | null } {
    const match = version.match(/^(v?)?(\d+).(\d+).(\d+)(?:-([0-9A-Za-z.-]+))?(?:\+([0-9A-Za-z.-]+))?$/);
    if (!match) {
        throw new Error("Invalid version format");
    }
    const [_, __, majorStr, minorStr, patchStr, prerelease, build] = match;
    const major = parseInt(majorStr, 10);
    const minor = parseInt(minorStr, 10);
    const patch = parseInt(patchStr, 10);
    return {
        major,
        minor,
        patch,
        prerelease: prerelease || null,
        build: build || null
    };
}
```