"""
IP address and request utilities.

Used across all phases for login history, rate limiting, security events.
"""


def get_client_ip(request) -> str:
    """Extract the real client IP from the request, respecting proxy headers."""
    x_forwarded_for = request.META.get("HTTP_X_FORWARDED_FOR")
    if x_forwarded_for:
        return x_forwarded_for.split(",")[0].strip()
    return request.META.get("REMOTE_ADDR", "")


def get_user_agent(request) -> str:
    """Extract User-Agent header from request."""
    return request.META.get("HTTP_USER_AGENT", "")


def get_device_fingerprint(request) -> str:
    """
    Generate a simple device fingerprint from request headers.

    Combines IP + User-Agent + Accept-Language for basic fingerprinting.
    """
    parts = [
        get_client_ip(request),
        get_user_agent(request),
        request.META.get("HTTP_ACCEPT_LANGUAGE", ""),
    ]
    import hashlib
    raw = "|".join(parts)
    return hashlib.sha256(raw.encode()).hexdigest()[:32]