try:
    import time
    from sonic_sfp.sfputilbase import SfpUtilBase
except ImportError as e:
    raise ImportError(str(e) + "- required module not found")

SFP_STATUS_INSERTED = '1'
SFP_STATUS_REMOVED = '0'


class SfpUtil(SfpUtilBase):
    """Platform specific SfpUtill class"""

    _port_start = 0
    _port_end = 53
    _qsfp_port_start = 48
    _ports_in_block = 54

    _port_to_eeprom_mapping = {}
    _port_to_i2c_mapping = {
        0: 37,
        1: 38,
        2: 39,
        3: 40,
        4: 41,
        5: 42,
        6: 43,
        7: 44,
        8: 45,
        9: 46,
        10: 47,
        11: 48,
        12: 49,
        13: 50,
        14: 51,
        15: 52,
        16: 53,
        17: 54,
        18: 55,
        19: 56,
        20: 57,
        21: 58,
        22: 59,
        23: 60,
        24: 61,
        25: 62,
        26: 63,
        27: 64,
        28: 65,
        29: 66,
        30: 67,
        31: 68,
        32: 69,
        33: 70,
        34: 71,
        35: 72,
        36: 73,
        37: 74,
        38: 75,
        39: 76,
        40: 77,
        41: 78,
        42: 79,
        43: 80,
        44: 81,
        45: 82,
        46: 83,
        47: 84,
        48: 21,
        49: 22,
        50: 23,
        51: 24,
        52: 25,
        53: 26,
    }

    _qsfp_ports = list(range(_qsfp_port_start, _ports_in_block + 1))

    _present_status = dict()

    def __init__(self):
        eeprom_path = '/sys/bus/i2c/devices/{0}-0050/sfp_eeprom'
        for x in range(self._port_start, self._port_end + 1):
            port_eeprom_path = eeprom_path.format(self._port_to_i2c_mapping[x])
            self._port_to_eeprom_mapping[x] = port_eeprom_path
            self._present_status[x] = SFP_STATUS_REMOVED

        SfpUtilBase.__init__(self)

    def reset(self, port_num):
        # Check for invalid port_num
        if port_num < self._qsfp_port_start or port_num > self._port_end:
            print("Error: port %d is not qsfp port" % port_num)
            return False

        path = "/sys/bus/i2c/devices/{0}-0050/sfp_port_reset"
        port_ps = path.format(self._port_to_i2c_mapping[port_num])

        try:
            reg_file = open(port_ps, 'w')
        except IOError as e:
            print("Error: unable to open file: %s" % str(e))
            return False

        # toggle reset
        reg_file.seek(0)
        reg_file.write('1')
        time.sleep(1)
        reg_file.seek(0)
        reg_file.write('0')
        reg_file.close()
        return True

    def set_low_power_mode(self, port_nuM, lpmode):
        raise NotImplementedError

    def get_low_power_mode(self, port_num):
        raise NotImplementedError

    def get_presence(self, port_num):
        # Check for invalid port_num
        if port_num < self._port_start or port_num > self._port_end:
            return False

        path = "/sys/bus/i2c/devices/{0}-0050/sfp_is_present"
        port_ps = path.format(self._port_to_i2c_mapping[port_num])

        reg_value = '0'
        try:
            reg_file = open(port_ps)
            reg_value = reg_file.readline().rstrip()
            reg_file.close()
        except IOError as e:
            print("Error: unable to access file: %s" % str(e))
            return False

        if reg_value == '1':
            return True

        return False

    def get_transceiver_change_event(self, timeout=0):
        raise NotImplementedError

    @property
    def port_start(self):
        return self._port_start

    @property
    def port_end(self):
        return self._port_end

    @property
    def qsfp_ports(self):
        return self._qsfp_ports

    @property
    def port_to_eeprom_mapping(self):
        return self._port_to_eeprom_mapping

    def get_transceiver_change_event(self, timeout=0):
        ret_present = dict()
        for phy_port in range(self._port_start, self._port_end + 1):
            last_present_status = SFP_STATUS_INSERTED if self.get_presence(phy_port) else SFP_STATUS_REMOVED
            if self._present_status[phy_port] != last_present_status:
                ret_present[phy_port] = last_present_status
                self._present_status[phy_port] = last_present_status

        time.sleep(2)

        return True, ret_present