import struct
from logging import Logger

from .constants import RESET, NO_RESET
from leahi_dialin.common.msg_defs import MsgIds, MsgFieldPositions
from leahi_dialin.common.td_defs import TDTemperatureSensorNames
from leahi_dialin.protocols.CAN import DenaliMessage, DenaliChannels
from leahi_dialin.utils.base import AbstractSubSystem, publish
from leahi_dialin.utils.checks import check_broadcast_interval_override_ms
from leahi_dialin.utils.conversions import integer_to_bytearray, float_to_bytearray


class TDTemperatureSensors(AbstractSubSystem):
    """
    Treatment Delivery (TD) Dialin API sub-class for temperature related commands.
    """

    def __init__(self, can_interface, logger: Logger):
        """
        TDTemperatureSensors constructor

        """
        super().__init__()
        self.can_interface = can_interface
        self.logger = logger

        if self.can_interface is not None:
            channel_id = DenaliChannels.td_sync_broadcast_ch_id
            self.msg_id_td_temperature_data = MsgIds.MSG_ID_TD_TEMPERATURE_DATA.value
            self.can_interface.register_receiving_publication_function(channel_id, self.msg_id_td_temperature_data,
                                                                       self._handler_temperature_sync)
        self.td_temperatures_status = {TDTemperatureSensorNames.H23_TEMP.name: 0.0}
        self.td_temperature_timestamp = 0.0

    @publish(["msg_id_td_temperature_data",
        "td_temperatures_status",
        "td_temperature_timestamp"
    ])
    def _handler_temperature_sync(self, message, timestamp=0.0):
        """
        Handles published temperature data messages.  Temperature data are captured
        for reference.

        @param message:  published temperature data message
        @return: none
        """
        baro = struct.unpack('f', bytearray(
            message['message'][MsgFieldPositions.START_POS_FIELD_1:MsgFieldPositions.END_POS_FIELD_1]))[0]

        self.td_temperatures_status[TDTemperatureSensorNames.H23_TEMP.name] = baro
        self.td_temperature_timestamp = timestamp

    def cmd_temperature_sensor_override(self, sensor: int, temperature: float,  reset: int = NO_RESET) -> int:
        """
        Constructs and sends the measured temperature sensor override command
    .
        Constraints:
            Must be logged into TD.

        @param sensor: int - sensor ID
        @param temperature:  float - measured temperature in C
        @param reset:  integer - 1 to reset a previous override, 0 to override
        @return: 1 if successful, zero otherwise
        """

        rst = integer_to_bytearray(reset)
        sen = integer_to_bytearray(sensor)
        prs = float_to_bytearray(temperature)
        payload = rst + prs + sen

        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_td_ch_id,
                                              message_id=MsgIds.MSG_ID_TD_TEMPERATURE_OVERRIDE.value,
                                              payload=payload)

        self.logger.debug("override temperature sensor")

        # Send message
        received_message = self.can_interface.send(message)

        # If there is content...
        if received_message is not None:
            if reset == RESET:
                str_res = "reset back to normal.  "
            else:
                str_res = str(prs) + " C.  "
            self.logger.debug("temperature (measured)) overridden to " + str_res +
                              str(received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]))
            # response payload is OK or not OK
            return received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]
        else:
            self.logger.debug("Timeout!!!!")
            return False

    def cmd_temperature_sensors_broadcast_interval_override(self, ms: int, reset: int = NO_RESET) -> int:
        """
        Constructs and sends the measured temperature sensors broadcast interval override command
        Constraints:
            Must be logged into TD.
            Given interval must be non-zero and a multiple of the TD general task interval (50 ms).

        @param ms:  integer - interval (in ms) to override with
        @param reset:  integer - 1 to reset a previous override, 0 to override
        @return: 1 if successful, zero otherwise
        """

        if not check_broadcast_interval_override_ms(ms):
            return False

        rst = integer_to_bytearray(reset)
        mis = integer_to_bytearray(ms)
        payload = rst + mis

        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_td_ch_id,
                                              message_id=MsgIds.MSG_ID_TD_TEMPERATURE_PUBLISH_INTERVAL_OVERRIDE_REQUEST.value,
                                              payload=payload)

        self.logger.debug("override temperature sensors broadcast interval")

        # Send message
        received_message = self.can_interface.send(message)

        # If there is content...
        if received_message is not None:
            # self.logger.debug(received_message)
            if reset == RESET:
                str_res = "reset back to normal: "
            else:
                str_res = str(ms) + " ms: "
            self.logger.debug("Temperature sensors broadcast interval overridden to " + str_res +
                              str(received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]))
            # response payload is OK or not OK
            return received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]
        else:
            self.logger.debug("Timeout!!!!")
            return False