# -*- coding: utf-8 -*-
#
# SPDX-FileCopyrightText: © 2017 The glucometerutils Authors
# SPDX-License-Identifier: MIT
"""Driver for FreeStyle InsuLinx devices.

Supported features:
    - get readings;
    - get and set date and time;
    - get serial number and software version.

Expected device path: /dev/hidraw9 or similar HID device. Optional when using
HIDAPI.

WARNING: currently untested! Based off reverse engineering notes provided by
Xavier Claessens.

"""

import collections
import datetime
from collections.abc import Generator
from typing import NoReturn, Optional

from glucometerutils import common
from glucometerutils.support import freestyle

# The type is a string because it precedes the parsing of the object.
_TYPE_GLUCOSE_READING = "0"

_InsulinxReading = collections.namedtuple(
    "_InsulinxReading",
    (
        "type",  # 0 = blood glucose
        "id",
        "month",
        "day",
        "year",  # year is two-digits
        "hour",
        "minute",
        "unknown1",
        "unknown2",
        "unknown3",
        "unknown4",
        "unknown5",
        "unknown6",
        "value",
        "unknown7",
        "unknown8",
    ),
)


class Device(freestyle.FreeStyleHidDevice):
    """Glucometer driver for FreeStyle InsuLinux devices."""

    def __init__(self, device_path: Optional[str]) -> None:
        super().__init__(0x3460, device_path)

    def get_meter_info(self) -> common.MeterInfo:
        """Return the device information in structured form."""
        return common.MeterInfo(
            "FreeStyle InsuLinx",
            serial_number=self.get_serial_number(),
            version_info=("Software version: " + self._get_version(),),
            native_unit=self.get_glucose_unit(),
        )

    def get_glucose_unit(self) -> common.Unit:  # pylint: disable=no-self-use
        """Returns the glucose unit of the device."""
        return common.Unit.MG_DL

    def get_readings(self) -> Generator[common.AnyReading, None, None]:
        """Iterate through the reading records in the device."""
        for record in self._session.query_multirecord(b"$result?"):
            if not record or record[0] != _TYPE_GLUCOSE_READING:
                continue

            # Build a reading object by parsing each of the entries in the CSV
            # as integers.
            raw_reading = _InsulinxReading._make([int(v) for v in record])

            timestamp = datetime.datetime(
                raw_reading.year + 2000,
                raw_reading.month,
                raw_reading.day,
                raw_reading.hour,
                raw_reading.minute,
            )

            yield common.GlucoseReading(timestamp, raw_reading.value)

    def zero_log(self) -> NoReturn:
        raise NotImplementedError