import logging
import sys

import hqt.logging as hqt_logging
from hqt.config import Settings


def test_setup_logging_does_not_write_to_terminal(tmp_path, monkeypatch):
    """setup_logging must NOT attach a StreamHandler that writes to the real
    terminal stderr/stdout.

    The TUI is a Textual app that paints to sys.__stderr__. A root-logger
    StreamHandler bound to that same fd writes raw log lines straight onto the
    pane Textual owns, corrupting tmux's grid — visible as rendering artifacts
    when switching back to the hqt window. Logs must go to file only.
    """
    settings = Settings(db_path=tmp_path / "hqt.db")
    monkeypatch.setattr(hqt_logging, "get_settings", lambda: settings)

    root = logging.getLogger()
    saved_handlers = root.handlers[:]
    saved_level = root.level
    try:
        root.handlers.clear()
        hqt_logging.setup_logging()

        terminal_streams = {sys.stderr, sys.__stderr__, sys.stdout, sys.__stdout__}
        offending = [
            h
            for h in root.handlers
            # FileHandler subclasses StreamHandler but writes to a file, not the terminal.
            if type(h) is logging.StreamHandler
            and getattr(h, "stream", None) in terminal_streams
        ]
        assert not offending, (
            f"setup_logging attached a terminal StreamHandler: {offending}"
        )
        # Logs are still captured to a file.
        assert any(isinstance(h, logging.FileHandler) for h in root.handlers)
    finally:
        root.handlers[:] = saved_handlers
        root.setLevel(saved_level)