import hashlib
from user_agents import parse

# Common bot patterns
BOT_PATTERNS = [
    "googlebot", "bingbot", "yandexbot", "baidubot", "duckduckbot",
    "slurp", "crawler", "spider", "bot", "scraper", "monitor",
    "curl", "wget", "python-requests", "httpie", "postman",
    "facebookexternalhit", "twitterbot", "linkedinbot", "slackbot",
    "discordbot", "telegrambot", "whatsapp", "applebot",
]


def is_bot(user_agent: str) -> bool:
    """Check if a user agent is a known bot."""
    ua_lower = user_agent.lower()
    return any(pattern in ua_lower for pattern in BOT_PATTERNS)


def parse_user_agent(ua_string: str) -> dict:
    """Parse user agent string into browser, os, device info."""
    parsed = parse(ua_string)
    return {
        "browser": parsed.browser.family if parsed.browser else "Unknown",
        "os": parsed.os.family if parsed.os else "Unknown",
        "device": parsed.device.family if parsed.device else "Unknown",
        "is_mobile": parsed.is_mobile,
        "is_tablet": parsed.is_tablet,
        "is_bot": parsed.is_bot,
    }


def classify_device(parsed_ua: dict) -> str:
    """Classify device into a simple category."""
    if parsed_ua["is_mobile"]:
        return "mobile"
    if parsed_ua["is_tablet"]:
        return "tablet"
    return "desktop"


def hash_ip(ip: str) -> str:
    """Hash an IP address for privacy."""
    return hashlib.sha256(ip.encode()).hexdigest()[:16]


def get_country_from_ip(ip: str) -> str:
    """
    Simple geo lookup. For production, use MaxMind GeoIP2 database.
    For now, return 'Unknown' — geo can be added later.
    """
    return "Unknown"


def process_visitor(client_ip: str, headers: dict, url: str) -> dict:
    """Process a visitor request and extract analytics data."""
    ua_string = headers.get("User-Agent", "Unknown")
    referrer = headers.get("Referer", headers.get("Referer", ""))

    parsed_ua = parse_user_agent(ua_string)
    bot = parsed_ua["is_bot"] or is_bot(ua_string)

    return {
        "page": url,
        "referrer": referrer,
        "country": get_country_from_ip(client_ip),
        "city": "Unknown",
        "browser": parsed_ua["browser"],
        "os": parsed_ua["os"],
        "device": classify_device(parsed_ua),
        "is_bot": 1 if bot else 0,
        "ip_hash": hash_ip(client_ip),
    }