import hashlib
import traceback
import threading
from django.core.signals import got_request_exception
from django.dispatch import receiver


@receiver(got_request_exception)
def log_request_exception(sender, request, **kwargs):
    def _save():
        try:
            import sys
            from .models import ErrorLog

            exc_info = sys.exc_info()
            if not exc_info[0]:
                return

            exception_type = exc_info[0].__name__
            tb_string = ''.join(traceback.format_exception(*exc_info))
            message = str(exc_info[1]) if exc_info[1] else ''

            hash_input = f"{exception_type}:{request.path}:{message[:100]}"
            hash_key = hashlib.md5(hash_input.encode()).hexdigest()

            user = None
            try:
                if hasattr(request, 'user') and request.user.is_authenticated:
                    user = request.user
            except Exception:
                pass

            ip_address = None
            x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR')
            if x_forwarded_for:
                ip_address = x_forwarded_for.split(',')[0].strip()
            else:
                ip_address = request.META.get('REMOTE_ADDR')

            existing = ErrorLog.objects.filter(hash_key=hash_key).first()
            if existing:
                existing.occurrence_count += 1
                existing.save(update_fields=['occurrence_count', 'timestamp'])
            else:
                ErrorLog.objects.create(
                    level='ERROR',
                    message=message[:1000],
                    module='request',
                    function='process_request',
                    exception_type=exception_type,
                    traceback=tb_string,
                    user=user,
                    ip_address=ip_address,
                    path=request.path[:255],
                    hash_key=hash_key,
                )
        except Exception:
            pass

    thread = threading.Thread(target=_save)
    thread.daemon = True
    thread.start()