"""TelegramAdapter wedged-getUpdates detection via pending_update_count.

PTB can report ``updater.running == True`` while its long-poll consumer is
silently stuck (observed on WSL2), so DMs queue in the Bot API and never reach
handlers (#42909). ``get_me()`` stays healthy (general request path), so the
CLOSE-WAIT heartbeat is blind to it. ``_probe_pending_updates`` watches
``get_webhook_info().pending_update_count`` and escalates to the existing
network-error recovery ladder after two consecutive stuck probes.
"""
import sys
from unittest.mock import AsyncMock, MagicMock, patch

import pytest

from gateway.config import PlatformConfig


def _ensure_telegram_mock():
    if "telegram" in sys.modules and hasattr(sys.modules["telegram"], "__file__"):
        return
    mod = MagicMock()
    mod.error.NetworkError = type("NetworkError", (OSError,), {})
    mod.error.TimedOut = type("TimedOut", (OSError,), {})
    mod.error.BadRequest = type("BadRequest", (Exception,), {})
    for name in ("telegram", "telegram.ext", "telegram.constants", "telegram.request"):
        sys.modules.setdefault(name, mod)
    sys.modules.setdefault("telegram.error", mod.error)


_ensure_telegram_mock()

from plugins.platforms.telegram.adapter import TelegramAdapter  # noqa: E402


def _make_adapter(*, pending: int) -> TelegramAdapter:
    adapter = TelegramAdapter(PlatformConfig(enabled=True, token="***"))
    adapter._webhook_mode = False
    adapter._app = MagicMock()
    adapter._app.updater.running = True
    bot = MagicMock()
    bot.get_webhook_info = AsyncMock(
        return_value=MagicMock(pending_update_count=pending)
    )
    adapter._app.bot = bot
    adapter._bot = bot
    return adapter


@pytest.mark.asyncio
async def test_single_stuck_probe_does_not_escalate():
    """One probe with a queued update only increments the counter."""
    adapter = _make_adapter(pending=3)
    with patch.object(adapter, "_handle_polling_network_error", new=AsyncMock()) as rec:
        await adapter._probe_pending_updates(adapter._app.bot, 5)
    assert adapter._polling_pending_stuck_count == 1
    rec.assert_not_called()


@pytest.mark.asyncio
async def test_two_consecutive_stuck_probes_trigger_recovery():
    """Second consecutive stuck probe routes into the recovery ladder."""
    adapter = _make_adapter(pending=2)
    recovery = AsyncMock()
    with patch.object(adapter, "_handle_polling_network_error", new=recovery):
        await adapter._probe_pending_updates(adapter._app.bot, 5)
        assert adapter._polling_pending_stuck_count == 1
        await adapter._probe_pending_updates(adapter._app.bot, 5)
        # Let the scheduled recovery task run.
        task = adapter._polling_error_task
        assert task is not None
        await task
    recovery.assert_awaited_once()
    # Counter resets after escalation so a fresh wedge starts from zero.
    assert adapter._polling_pending_stuck_count == 0


@pytest.mark.asyncio
async def test_zero_pending_resets_counter():
    """A drained queue clears any prior stuck count without escalating."""
    adapter = _make_adapter(pending=0)
    adapter._polling_pending_stuck_count = 1
    with patch.object(adapter, "_handle_polling_network_error", new=AsyncMock()) as rec:
        await adapter._probe_pending_updates(adapter._app.bot, 5)
    assert adapter._polling_pending_stuck_count == 0
    rec.assert_not_called()


@pytest.mark.asyncio
async def test_webhook_mode_is_noop():
    """Webhook mode holds no server-side queue — probe never runs."""
    adapter = _make_adapter(pending=9)
    adapter._webhook_mode = True
    await adapter._probe_pending_updates(adapter._app.bot, 5)
    adapter._app.bot.get_webhook_info.assert_not_called()
    assert adapter._polling_pending_stuck_count == 0


@pytest.mark.asyncio
async def test_no_probe_when_updater_not_running():
    """If the updater isn't running, recovery is already someone else's job."""
    adapter = _make_adapter(pending=9)
    adapter._app.updater.running = False
    adapter._polling_pending_stuck_count = 1
    await adapter._probe_pending_updates(adapter._app.bot, 5)
    adapter._app.bot.get_webhook_info.assert_not_called()
    assert adapter._polling_pending_stuck_count == 0


@pytest.mark.asyncio
async def test_reconnect_in_flight_skips_probe():
    """An active recovery task owns the connection — don't double-trigger."""
    adapter = _make_adapter(pending=9)
    inflight = MagicMock()
    inflight.done.return_value = False
    adapter._polling_error_task = inflight
    await adapter._probe_pending_updates(adapter._app.bot, 5)
    adapter._app.bot.get_webhook_info.assert_not_called()