###########################################################################
#
# Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
#
# THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
# WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
#
# @file load_cells.py
#
# @author (last) Peter Lucia
# @date (last) 10-Nov-2020
# @author (original) Sean
# @date (original) 14-Apr-2020
#
############################################################################
import struct
from ..utils.conversions import integer_to_bytearray, float_to_bytearray
from ..common.msg_defs import MsgIds, MsgFieldPositions
from .constants import RESET,NO_RESET
from ..protocols.CAN import (DenaliMessage,
                             DenaliChannels)
from ..utils.base import _AbstractSubSystem, _publish
from logging import Logger


class DGLoadCells(_AbstractSubSystem):
    """
    DGLoadCells

    Dialysate Generator (DG) Dialin API sub-class for load cell related commands.
    """

    # Load Cell IDs
    LOAD_CELL_A1 = 0
    LOAD_CELL_A2 = 1
    LOAD_CELL_B1 = 2
    LOAD_CELL_B2 = 3

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

        @param can_interface: Denali Can Messenger object
        """
        super().__init__()
        self.can_interface = can_interface
        self.logger = logger

        if self.can_interface is not None:
            channel_id = DenaliChannels.dg_sync_broadcast_ch_id
            msg_id = MsgIds.MSG_ID_LOAD_CELL_READINGS.value
            self.can_interface.register_receiving_publication_function(channel_id, msg_id,
                                                                       self._handler_load_cells_sync)

        self.load_cell_A1 = 0.0
        self.load_cell_A2 = 0.0
        self.load_cell_B1 = 0.0
        self.load_cell_B2 = 0.0

    def get_load_cells(self):
        """
        Gets the current load cell weights

        @return: List containing load cell values: [A1, A2, B1, B2]
        """
        return [self.load_cell_A1, self.load_cell_A2, self.load_cell_B1, self.load_cell_B2]

    @_publish(["load_cell_A1", "load_cell_A2", "load_cell_B1", "load_cell_B2"])
    def _handler_load_cells_sync(self, message):
        """
        Handles published load cell data messages.  Load cell data are captured
        for reference.

        @param message:  published load cell data message
        @return: None
        """

        a1 = struct.unpack('f', bytearray(
            message['message'][MsgFieldPositions.START_POS_FIELD_1:MsgFieldPositions.END_POS_FIELD_1]))
        a2 = struct.unpack('f', bytearray(
            message['message'][MsgFieldPositions.START_POS_FIELD_2:MsgFieldPositions.END_POS_FIELD_2]))
        b1 = struct.unpack('f', bytearray(
            message['message'][MsgFieldPositions.START_POS_FIELD_3:MsgFieldPositions.END_POS_FIELD_3]))
        b2 = struct.unpack('f', bytearray(
            message['message'][MsgFieldPositions.START_POS_FIELD_4:MsgFieldPositions.END_POS_FIELD_4]))

        self.load_cell_A1 = a1[0]
        self.load_cell_A2 = a2[0]
        self.load_cell_B1 = b1[0]
        self.load_cell_B2 = b2[0]

    def cmd_load_cell_override(self, grams, sensor, reset=NO_RESET):
        """
        Constructs and sends the load cell override command
        Constraints:
            Must be logged into DG.
            Given sensor must be one of the sensors listed below.

        @param grams:  float - weight (in grams) to override sensor with
        @param sensor: unsigned int - sensor ID
        @param reset:  integer - 1 to reset a previous override, 0 to override
        @return: 1 if successful, zero otherwise

        Load Cell sensor IDs: \n
            0 = A1 \n
            1 = A2 \n
            2 = B1 \n
            3 = B2 \n
        """

        rst = integer_to_bytearray(reset)
        grm = float_to_bytearray(grams)
        idx = integer_to_bytearray(sensor)
        payload = rst + grm + idx

        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
                                              message_id=MsgIds.MSG_ID_LOAD_CELL_OVERRIDE.value,
                                              payload=payload)

        self.logger.debug("override load cell weight value for sensor " + str(sensor))

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

        # If there is content...
        if received_message is not None:
            # response payload is OK or not OK
            return received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]
        else:
            self.logger.debug("Timeout!!!!")
            return False

    def cmd_load_cell_data_broadcast_interval_override(self, ms, reset=NO_RESET):
        """
        Constructs and sends the load cell data broadcast interval override command
        Constraints:
            Must be logged into DG.
            Given interval must be non-zero and a multiple of the DG priority task interval (10 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
        """

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

        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
                                              message_id=MsgIds.MSG_ID_LOAD_CELLL_SEND_INTERVAL_OVERRIDE.value,
                                              payload=payload)

        self.logger.debug("override DG load cell broadcast interval")

        # 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(ms) + " ms: "
            self.logger.debug("Load cell data 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