# Copyright (c) 2026 DeepBeepMeep - part of WanGP, WanGP Community License 2.0 (see LICENSE.txt)
"""Identify writes to lost asyncio transports without filtering their warnings."""
import asyncio
import logging
import sys
import traceback
import weakref


class LostSocketDiagnostics(logging.Handler):
    def __init__(self):
        super().__init__(logging.WARNING)
        self.reported = weakref.WeakSet()

    def emit(self, record):
        if record.getMessage() != "socket.send() raised exception.":
            return
        frame = sys._getframe()
        try:
            while frame is not None:
                transport = frame.f_locals.get("self")
                if isinstance(transport, asyncio.BaseTransport):
                    if transport in self.reported:
                        return
                    self.reported.add(transport)
                    protocol = transport.get_protocol()
                    cycle = getattr(protocol, "cycle", None)
                    scope = getattr(protocol, "scope", None) or getattr(cycle, "scope", None) or {}
                    logging.getLogger("wangp.network").error(
                        "Write after connection loss: transport=%s protocol=%s method=%s path=%s peer=%s closing=%s lost_writes=%s\n%s",
                        type(transport).__name__, type(protocol).__name__, scope.get("method"), scope.get("path"),
                        transport.get_extra_info("peername"), transport.is_closing(), getattr(transport, "_conn_lost", None),
                        "".join(traceback.format_stack(frame, limit=20)),
                    )
                    return
                frame = frame.f_back
        finally:
            del frame


def install_network_diagnostics():
    logger = logging.getLogger("asyncio")
    if not any(isinstance(handler, LostSocketDiagnostics) for handler in logger.handlers):
        logger.addHandler(LostSocketDiagnostics())