"""Test the functionality in the scan_directories module."""

from datetime import datetime, timedelta
from copy import copy
import json
from math import floor

from openflexure_microscope_server.scan_directories import ScanData

MOCK_START_TIME = datetime(
    year=2024,
    month=12,
    day=25,
    hour=11,
    minute=0,
    second=0,
    microsecond=1234,
)

MOCK_END_TIME = datetime(
    year=2024,
    month=12,
    day=25,
    hour=12,
    minute=29,
    second=3,
    microsecond=5678,
)


def _fake_scan_data(**kwargs) -> ScanData:
    """Make fake scan data, the start time is now. Final properties are not added.

    :param **kwargs: Key word arguments can be used to override other values.
    """
    data_dict = {
        "scan_name": "fake_scan_0001",
        "starting_position": {"x": 123, "y": 456, "z": 789},
        "overlap": 0.1,
        "max_dist": 100000,
        "dx": 100,
        "dy": 100,
        "autofocus_dz": 1000,
        "autofocus_on": True,
        "start_time": copy(MOCK_START_TIME),
        "skip_background": True,
        "stitch_automatically": True,
        "correlation_resize": 0.25,
        "save_resolution": (1000, 1000),
    }
    for key, value in kwargs.items():
        data_dict[key] = value
    return ScanData(**data_dict)


def test_set_final_data():
    """Check that adding final data to a ScanData object works as expected."""
    scan_data = _fake_scan_data()

    assert scan_data.image_count == 0
    assert scan_data.duration is None
    assert scan_data.scan_result is None

    # Quickly take 123 images!
    scan_data.image_count += 123
    # Should set duration based on finishing at datetime.now()
    scan_data.set_final_data(result="Success")
    expected_duration = datetime.now() - MOCK_START_TIME
    expected_duration_s = expected_duration.total_seconds()
    scan_duration_s = scan_data.duration.total_seconds()

    assert scan_data.image_count == 123
    assert expected_duration_s - 1 < scan_duration_s < expected_duration_s + 1
    assert scan_data.scan_result == "Success"


def test_custom_serialisation():
    """Check that the custom serialisation in ScanData works as expected."""
    scan_data = _fake_scan_data()
    # Serialise to string then load directly as json
    scan_data_dict = json.loads(scan_data.model_dump_json())
    assert scan_data_dict["start_time"] == "2024-12-25_11:00:00"
    assert scan_data_dict["image_count"] == 0
    assert scan_data_dict["duration"] == "Unknown"
    assert scan_data_dict["scan_result"] == "Unknown"

    scan_data.image_count += 123
    scan_data.set_final_data(result="Success")
    # Can't mock datetime.now as datetime is immutable. So just replace duration
    scan_data.duration = MOCK_END_TIME - scan_data.start_time
    scan_data_dict = json.loads(scan_data.model_dump_json())
    assert scan_data_dict["image_count"] == 123
    assert scan_data_dict["duration"] == "1:29:03"
    assert scan_data_dict["scan_result"] == "Success"


def test_round_trip_not_finalised():
    """Check that ScanData without final data can be serialised and deserialised."""
    scan_data = _fake_scan_data()
    scan_data_dict = json.loads(scan_data.model_dump_json())
    scan_data_reloaded = ScanData(**scan_data_dict)

    # For the round trip to be equal we must remove microseconds from the start
    # time as they are not saved
    scan_data.start_time = scan_data.start_time.replace(microsecond=0)
    assert scan_data == scan_data_reloaded


def test_round_trip_finalised():
    """Check that finalised ScanData can be serialised and deserialised."""
    scan_data = _fake_scan_data()
    # Finalise the data.
    scan_data.image_count += 123
    scan_data.set_final_data(result="Success")

    scan_data_dict = json.loads(scan_data.model_dump_json())
    scan_data_reloaded = ScanData(**scan_data_dict)

    # For the round trip to be equal we must remove microseconds from the start
    # time and duration as they are not saved
    scan_data.model_copy(update={})
    scan_data.start_time = scan_data.start_time.replace(microsecond=0)
    scan_data.duration = timedelta(seconds=floor(scan_data.duration.total_seconds()))

    assert scan_data == scan_data_reloaded