import logging
import os

from gunicorn.glogging import Logger

TRUSTED_PROXIES = {
    ip.strip()
    for ip in os.environ.get("TRUSTED_PROXIES", "").split(",")
    if ip.strip()
}


class HealthCheckFilter(logging.Filter):
    def filter(self, record):
        message = record.getMessage()
        return "kube-probe" not in message


class CustomLogger(Logger):
    def atoms(self, resp, req, environ, request_time):
        atoms = super().atoms(resp, req, environ, request_time)
        atoms["{client-ip}e"] = self._get_client_ip(environ)
        return atoms

    @staticmethod
    def _get_client_ip(environ):
        remote_addr = environ.get("REMOTE_ADDR", "-")
        xff = environ.get("HTTP_X_FORWARDED_FOR", "")
        if not xff:
            return remote_addr
        # Walk the chain from right to left, skipping trusted proxies
        ips = [ip.strip() for ip in xff.split(",")]
        for ip in reversed(ips):
            if ip not in TRUSTED_PROXIES:
                return ip
        # All IPs in the chain are trusted; fall back to the leftmost
        return ips[0]


logger_class = CustomLogger
access_log_format = '%({client-ip}e)s %(l)s %(u)s %(t)s "%(r)s" %(s)s %(b)s "%(f)s" "%(a)s"'

logconfig_dict = {
    "version": 1,
    "disable_existing_loggers": False,
    "filters": {
        "health_check": {
            "()": HealthCheckFilter,
        },
    },
    "handlers": {
        "console": {
            "class": "logging.StreamHandler",
            "stream": "ext://sys.stderr",
        },
        "access_console": {
            "class": "logging.StreamHandler",
            "filters": ["health_check"],
            "stream": "ext://sys.stdout",
        },
    },
    "root": {
        "level": "INFO",
        "handlers": ["console"],
    },
    "loggers": {
        "gunicorn.error": {
            "level": "INFO",
            "handlers": ["console"],
            "propagate": False,
        },
        "gunicorn.access": {
            "level": "INFO",
            "handlers": ["access_console"],
            "propagate": False,
        },
    },
}