"""
Tests for scan_processor task registry and control functions.

Tests cancel_scan_task, pause_scan_task, stop_scan_task, and the
done-callback that removes tasks from the registry on completion.
"""

import asyncio
import pytest
import sys
import os
from unittest.mock import MagicMock

sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))

from scan_processor import (
    _running_tasks,
    _cancel_reasons,
    cancel_scan_task,
    pause_scan_task,
    stop_scan_task,
)


class TestScanProcessorControl:
    """Tests for task registry and cancel/pause/stop functions."""

    def teardown_method(self, _method):
        """Clean up any test state from _running_tasks and _cancel_reasons."""
        for key in [9001, 8001, 8002, 7001]:
            _running_tasks.pop(key, None)
            _cancel_reasons.pop(key, None)

    # ── cancel_scan_task ───────────────────────────────────────────────────

    def test_cancel_scan_task_returns_false_when_no_task(self):
        """Returns False when no task is registered for the given scan id."""
        result = cancel_scan_task(99999)
        assert result is False

    def test_cancel_scan_task_returns_true_when_task_exists(self):
        """Returns True and calls task.cancel() when a live task is registered."""
        mock_task = MagicMock()
        mock_task.done.return_value = False
        _running_tasks[9001] = mock_task

        result = cancel_scan_task(9001)

        assert result is True
        mock_task.cancel.assert_called_once()

    def test_cancel_scan_task_returns_false_for_completed_task(self):
        """Returns False when the registered task is already done."""
        mock_task = MagicMock()
        mock_task.done.return_value = True
        _running_tasks[9001] = mock_task

        result = cancel_scan_task(9001)

        assert result is False
        mock_task.cancel.assert_not_called()

    # ── pause_scan_task ────────────────────────────────────────────────────

    def test_pause_sets_cancel_reason_paused(self):
        """pause_scan_task sets _cancel_reasons[id] = 'paused'."""
        mock_task = MagicMock()
        mock_task.done.return_value = False
        _running_tasks[8001] = mock_task

        pause_scan_task(8001)

        assert _cancel_reasons.get(8001) == 'paused'

    def test_pause_calls_cancel_on_task(self):
        """pause_scan_task triggers cancellation of the underlying task."""
        mock_task = MagicMock()
        mock_task.done.return_value = False
        _running_tasks[8001] = mock_task

        result = pause_scan_task(8001)

        assert result is True
        mock_task.cancel.assert_called_once()

    # ── stop_scan_task ─────────────────────────────────────────────────────

    def test_stop_sets_cancel_reason_cancelled(self):
        """stop_scan_task sets _cancel_reasons[id] = 'cancelled'."""
        mock_task = MagicMock()
        mock_task.done.return_value = False
        _running_tasks[8002] = mock_task

        stop_scan_task(8002)

        assert _cancel_reasons.get(8002) == 'cancelled'

    def test_stop_calls_cancel_on_task(self):
        """stop_scan_task triggers cancellation of the underlying task."""
        mock_task = MagicMock()
        mock_task.done.return_value = False
        _running_tasks[8002] = mock_task

        result = stop_scan_task(8002)

        assert result is True
        mock_task.cancel.assert_called_once()

    # ── done callback ──────────────────────────────────────────────────────

    def test_task_removed_from_registry_on_completion(self):
        """The done-callback registered by start_scan_processor removes the task."""

        async def run():
            async def quick():
                return

            task = asyncio.create_task(quick())
            _running_tasks[7001] = task
            task.add_done_callback(lambda _: _running_tasks.pop(7001, None))
            await task
            # Yield to let done callbacks fire
            await asyncio.sleep(0)
            return 7001 not in _running_tasks

        result = asyncio.run(run())
        assert result is True