import logging

from django.utils.crypto import get_random_string

from analytics.models import Attribution, PageView, UTMVisit


logger = logging.getLogger(__name__)

CORRELATION_COOKIE = "ms_cid"

# Portal, auth, health, assets, and transactional public endpoints.
_SKIP_PREFIXES = (
    "/portal/",
    "/admin/",
    "/accounts/",
    "/api/",
    "/healthz",
    "/static/",
    "/media/",
    "/unsubscribe/",
)
_SKIP_PATHS = frozenset({"/robots.txt", "/sitemap.xml", "/favicon.ico"})


class PublicPageViewMiddleware:
    """Record successful GET hits on public marketing pages."""

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        response = self.get_response(request)
        if _should_record_page_view(request, response):
            try:
                PageView.objects.create(path=request.path[:512])
            except Exception:
                logger.exception("Failed to record page view for %s", request.path)
        return response


def _should_record_page_view(request, response) -> bool:
    if request.method != "GET":
        return False
    if getattr(response, "status_code", 0) != 200:
        return False
    path = request.path
    if path in _SKIP_PATHS:
        return False
    return not any(path.startswith(prefix) for prefix in _SKIP_PREFIXES)


class UTMTrackingMiddleware:
    """Capture UTM params into UTMVisit and stash a correlation id cookie."""

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        cid = request.COOKIES.get(CORRELATION_COOKIE) or get_random_string(32)
        request.utm_correlation_id = cid

        params = request.GET
        has_utm = any(params.get(k) for k in (
            "utm_source", "utm_medium", "utm_campaign", "utm_term", "utm_content"
        ))
        if has_utm or params.get("utm_source"):
            UTMVisit.objects.create(
                correlation_id=cid,
                path=request.path[:512],
                referrer=(request.META.get("HTTP_REFERER") or "")[:1024],
                utm_source=params.get("utm_source", "")[:128],
                utm_medium=params.get("utm_medium", "")[:128],
                utm_campaign=params.get("utm_campaign", "")[:128],
                utm_term=params.get("utm_term", "")[:128],
                utm_content=params.get("utm_content", "")[:128],
                user_agent=(request.META.get("HTTP_USER_AGENT") or "")[:512],
            )

        response = self.get_response(request)
        if CORRELATION_COOKIE not in request.COOKIES:
            response.set_cookie(
                CORRELATION_COOKIE,
                cid,
                max_age=60 * 60 * 24 * 30,
                samesite="Lax",
            )
        return response


def attribute_lead_from_request(request, lead) -> Attribution | None:
    cid = getattr(request, "utm_correlation_id", None) or request.COOKIES.get(
        CORRELATION_COOKIE
    )
    visit = None
    if cid:
        visit = (
            UTMVisit.objects.filter(correlation_id=cid).order_by("-created_at").first()
        )
    return Attribution.objects.create(
        lead=lead,
        visit=visit,
        utm_source=visit.utm_source if visit else "",
        utm_medium=visit.utm_medium if visit else "",
        utm_campaign=visit.utm_campaign if visit else "",
    )