import re


def filter_links(links):
    '''
    input: {
        'internal': [{}],
        'external': [
            {
                "href": "xx",
                "text": "xxm",
                "title": "",
                "base_domain": "benlcollins.com"
            }
        ],
    }
    '''
    external_links = links["external"]
    filtered_links = [link for link in external_links if "google" not in link["base_domain"]]
    return filtered_links

def is_valid_domain(domain):
    # 正则表达式匹配域名格式
    pattern = r'^([a-zA-Z0-9-]+\.)+[a-zA-Z]{2,}$'
    return re.match(pattern, domain) is not None

def filter_local_domain(links):
    '''
    input: [{
            "href": "xx",
            "text": "xxm",
            "title": "",
            "base_domain": "benlcollins.com"
    }]
    '''
    filtered_links = []
    for link in links:
        if 'base_domain' in link and is_valid_domain(link['base_domain']):
            filtered_links.append(link)
    return filtered_links