import re

def parse_semver(s):
    if not isinstance(s, str):
        return None
    pattern = r'^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$'
    match = re.match(pattern, s)
    if match is None:
        return None
    major = int(match.group(1))
    minor = int(match.group(2))
    patch = int(match.group(3))
    prerelease = match.group(4)
    build = match.group(5)
    return {
        "major": major,
        "minor": minor,
        "patch": patch,
        "prerelease": prerelease,
        "build": build
    }