"""Unit tests for background dispatch service."""

from types import SimpleNamespace
from unittest.mock import AsyncMock, patch

import pytest

from backend.app.services.background_dispatch import (
    ActiveDispatchState,
    BackgroundDispatchService,
    DispatchEnqueueRejected,
    PrintDispatchJob,
)


@pytest.mark.asyncio
async def test_dispatch_rejects_when_printer_busy_printing():
    """Reject enqueue when target printer is already printing."""
    service = BackgroundDispatchService()

    with (
        patch(
            "backend.app.services.background_dispatch.printer_manager.get_status",
            return_value=SimpleNamespace(state="RUNNING", gcode_file="active.gcode.3mf"),
        ),
        pytest.raises(DispatchEnqueueRejected, match="currently busy printing"),
    ):
        await service.dispatch_reprint_archive(
            archive_id=1,
            archive_name="Test Archive",
            printer_id=10,
            printer_name="Printer A",
            options={},
            requested_by_user_id=None,
            requested_by_username=None,
        )


@pytest.mark.asyncio
async def test_dispatch_enqueues_job_and_broadcasts_state():
    """Enqueue succeeds and emits websocket queue update."""
    service = BackgroundDispatchService()

    with (
        patch("backend.app.services.background_dispatch.printer_manager.get_status", return_value=None),
        patch(
            "backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock
        ) as mock_broadcast,
    ):
        result = await service.dispatch_print_library_file(
            file_id=22,
            filename="cube.gcode.3mf",
            printer_id=7,
            printer_name="Printer B",
            options={"plate_id": 2},
            requested_by_user_id=5,
            requested_by_username="tester",
        )

    assert result["status"] == "dispatched"
    assert result["dispatch_job_id"] == 1
    assert result["dispatch_position"] == 1
    assert len(service._queued_jobs) == 1

    mock_broadcast.assert_awaited_once()
    payload = mock_broadcast.await_args.args[0]
    assert payload["type"] == "background_dispatch"
    assert payload["data"]["recent_event"]["status"] == "dispatched"


@pytest.mark.asyncio
async def test_dispatch_library_file_defaults_cleanup_flag_false():
    """cleanup_library_after_dispatch defaults to False when not passed — protects
    File Manager / Project Detail / queued-library-file paths from surprise deletion."""
    service = BackgroundDispatchService()

    with (
        patch("backend.app.services.background_dispatch.printer_manager.get_status", return_value=None),
        patch("backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock),
    ):
        await service.dispatch_print_library_file(
            file_id=1,
            filename="cube.gcode.3mf",
            printer_id=1,
            printer_name="Printer A",
            options={},
            requested_by_user_id=None,
            requested_by_username=None,
        )

    assert len(service._queued_jobs) == 1
    assert service._queued_jobs[0].cleanup_library_after_dispatch is False


@pytest.mark.asyncio
async def test_dispatch_library_file_propagates_cleanup_flag_true():
    """cleanup_library_after_dispatch=True arrives on the queued job so the runner
    can delete the transient LibraryFile after the print is accepted by the printer."""
    service = BackgroundDispatchService()

    with (
        patch("backend.app.services.background_dispatch.printer_manager.get_status", return_value=None),
        patch("backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock),
    ):
        await service.dispatch_print_library_file(
            file_id=1,
            filename="cube.gcode.3mf",
            printer_id=1,
            printer_name="Printer A",
            options={},
            requested_by_user_id=42,
            requested_by_username="alice",
            cleanup_library_after_dispatch=True,
        )

    assert len(service._queued_jobs) == 1
    job = service._queued_jobs[0]
    assert job.cleanup_library_after_dispatch is True
    # Sanity: other fields still wired correctly
    assert job.requested_by_user_id == 42
    assert job.requested_by_username == "alice"
    assert job.kind == "print_library_file"


@pytest.mark.asyncio
async def test_cancel_queued_job_removes_it_and_broadcasts():
    """Cancelling queued job removes it immediately."""
    service = BackgroundDispatchService()

    with (
        patch("backend.app.services.background_dispatch.printer_manager.get_status", return_value=None),
        patch(
            "backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock
        ) as mock_broadcast,
    ):
        result = await service.dispatch_reprint_archive(
            archive_id=1,
            archive_name="benchy.gcode.3mf",
            printer_id=1,
            printer_name="Printer 1",
            options={},
            requested_by_user_id=None,
            requested_by_username=None,
        )
        mock_broadcast.reset_mock()

        cancel_result = await service.cancel_job(result["dispatch_job_id"])

    assert cancel_result["cancelled"] is True
    assert cancel_result["pending"] is False
    assert len(service._queued_jobs) == 0
    assert service._batch_total == 0

    mock_broadcast.assert_awaited_once()
    payload = mock_broadcast.await_args.args[0]
    assert payload["data"]["recent_event"]["status"] == "cancelled"


@pytest.mark.asyncio
async def test_cancel_active_job_marks_pending_and_sets_cancel_flag():
    """Cancelling active job marks it as pending cancellation."""
    service = BackgroundDispatchService()
    job = PrintDispatchJob(
        id=42,
        kind="reprint_archive",
        source_id=100,
        source_name="gearbox.gcode.3mf",
        printer_id=3,
        printer_name="Printer C",
    )
    service._active_jobs[job.id] = ActiveDispatchState(job=job, message="Uploading...")

    with patch(
        "backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock
    ) as mock_broadcast:
        result = await service.cancel_job(job.id)

    assert result["cancelled"] is True
    assert result["pending"] is True
    assert job.id in service._cancel_requested_job_ids

    mock_broadcast.assert_awaited_once()
    payload = mock_broadcast.await_args.args[0]
    assert payload["data"]["recent_event"]["status"] == "cancelling"


def test_resolve_plate_id_uses_request_value_when_provided(tmp_path):
    """Explicit plate_id wins over auto-detection."""
    file_path = tmp_path / "dummy.3mf"
    file_path.write_text("not-a-zip")

    plate_id = BackgroundDispatchService._resolve_plate_id(file_path, requested_plate_id=9)
    assert plate_id == 9


def test_resolve_plate_id_auto_detects_from_3mf(tmp_path):
    """Auto-detect plate from Metadata/plate_X.gcode entry."""
    import zipfile

    file_path = tmp_path / "multi.3mf"
    with zipfile.ZipFile(file_path, "w") as zf:
        zf.writestr("Metadata/plate_7.gcode", b"G1 X0 Y0")

    plate_id = BackgroundDispatchService._resolve_plate_id(file_path, requested_plate_id=None)
    assert plate_id == 7


def test_is_sliced_file_recognizes_supported_extensions():
    """Only .gcode and .gcode.3mf should be accepted."""
    assert BackgroundDispatchService._is_sliced_file("part.gcode") is True
    assert BackgroundDispatchService._is_sliced_file("part.gcode.3mf") is True
    assert BackgroundDispatchService._is_sliced_file("part.3mf") is False


@pytest.mark.asyncio
async def test_cancel_job_not_found_returns_false():
    """Cancelling a nonexistent job returns not_found."""
    service = BackgroundDispatchService()

    with patch("backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock):
        result = await service.cancel_job(999)

    assert result["cancelled"] is False
    assert result["reason"] == "not_found"


@pytest.mark.asyncio
async def test_cancel_job_single_lock_covers_both_active_and_queued():
    """cancel_job checks both active and queued jobs under a single lock acquisition.

    Regression test for TOCTOU race: previously two separate lock acquisitions allowed
    the dispatcher loop to move a job from queue to active between them, causing cancel
    to find it in neither place.
    """
    service = BackgroundDispatchService()

    # Set up a job in the queue AND an active job for a different printer
    active_job = PrintDispatchJob(
        id=1,
        kind="reprint_archive",
        source_id=10,
        source_name="active.3mf",
        printer_id=1,
        printer_name="Printer 1",
    )
    service._active_jobs[active_job.id] = ActiveDispatchState(job=active_job, message="Uploading...")

    queued_job = PrintDispatchJob(
        id=2,
        kind="reprint_archive",
        source_id=20,
        source_name="queued.3mf",
        printer_id=2,
        printer_name="Printer 2",
    )
    service._queued_jobs.append(queued_job)
    service._batch_total = 2

    with patch(
        "backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock
    ) as mock_broadcast:
        # Cancel the queued job — should find it in single lock acquisition
        result = await service.cancel_job(2)

    assert result["cancelled"] is True
    assert result["pending"] is False
    assert len(service._queued_jobs) == 0
    # Active job should be untouched
    assert 1 in service._active_jobs

    mock_broadcast.assert_awaited_once()
    payload = mock_broadcast.await_args.args[0]
    assert payload["data"]["recent_event"]["status"] == "cancelled"


@pytest.mark.asyncio
async def test_mark_job_finished_resets_batch_when_all_done():
    """Batch counters reset after last job completes."""
    service = BackgroundDispatchService()
    job = PrintDispatchJob(
        id=1,
        kind="reprint_archive",
        source_id=10,
        source_name="test.3mf",
        printer_id=1,
        printer_name="Printer 1",
    )
    service._active_jobs[job.id] = ActiveDispatchState(job=job, message="Done")
    service._batch_total = 1

    with patch("backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock):
        await service._mark_job_finished(job, failed=False, message="Complete")

    assert service._batch_total == 0
    assert service._batch_completed == 0
    assert service._batch_failed == 0


@pytest.mark.asyncio
async def test_mark_job_finished_no_reset_when_jobs_remain():
    """Batch counters NOT reset when queued jobs remain."""
    service = BackgroundDispatchService()
    job = PrintDispatchJob(
        id=1,
        kind="reprint_archive",
        source_id=10,
        source_name="test.3mf",
        printer_id=1,
        printer_name="Printer 1",
    )
    remaining_job = PrintDispatchJob(
        id=2,
        kind="reprint_archive",
        source_id=20,
        source_name="next.3mf",
        printer_id=2,
        printer_name="Printer 2",
    )
    service._active_jobs[job.id] = ActiveDispatchState(job=job, message="Done")
    service._queued_jobs.append(remaining_job)
    service._batch_total = 2

    with patch("backend.app.services.background_dispatch.ws_manager.broadcast", new_callable=AsyncMock):
        await service._mark_job_finished(job, failed=False, message="Complete")

    # Batch counters should NOT be reset — remaining job still queued
    assert service._batch_total == 2
    assert service._batch_completed == 1


@pytest.mark.asyncio
async def test_mark_job_finished_batch_reset_rechecks_under_lock():
    """Batch reset re-checks condition inside second lock acquisition.

    Regression test for TOCTOU: a new dispatch between the two lock acquisitions
    could get its counters zeroed if the re-check is missing.
    """
    service = BackgroundDispatchService()
    job = PrintDispatchJob(
        id=1,
        kind="reprint_archive",
        source_id=10,
        source_name="test.3mf",
        printer_id=1,
        printer_name="Printer 1",
    )
    service._active_jobs[job.id] = ActiveDispatchState(job=job, message="Done")
    service._batch_total = 1

    original_broadcast = AsyncMock()

    async def inject_new_job_during_broadcast(msg):
        """Simulate a new dispatch arriving between the two lock acquisitions."""
        await original_broadcast(msg)
        # After broadcast (lock released), inject a new job before reset re-check
        if not service._queued_jobs:
            new_job = PrintDispatchJob(
                id=99,
                kind="reprint_archive",
                source_id=99,
                source_name="injected.3mf",
                printer_id=5,
                printer_name="Printer 5",
            )
            service._queued_jobs.append(new_job)
            service._batch_total = 1

    with patch(
        "backend.app.services.background_dispatch.ws_manager.broadcast",
        side_effect=inject_new_job_during_broadcast,
    ):
        await service._mark_job_finished(job, failed=False, message="Complete")

    # Re-check should prevent reset since a new job appeared
    assert service._batch_total == 1
    assert len(service._queued_jobs) == 1