# sfputil.py
#
# Platform-specific SFP transceiver interface for SONiC
#

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


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

    PORT_START = 0
    PORT_END = 53
    PORTS_IN_BLOCK = 32

    EEPROM_OFFSET = 20

    _port_to_eeprom_mapping = {}

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

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

    @property
    def qsfp_ports(self):
        return list(range(0, self.PORTS_IN_BLOCK + 1))

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

    def __init__(self):
        eeprom_path = "/sys/class/i2c-adapter/i2c-{0}/{0}-0050/eeprom"

        for x in range(0, self.port_end + 1):
            self._port_to_eeprom_mapping[x] = eeprom_path.format(
                x + self.EEPROM_OFFSET)

        SfpUtilBase.__init__(self)

    def get_presence(self, port_name):
        # modify by zhw to get sfp presence
        # Check for invalid port_num
        port_num = int(port_name[8:])

        if port_num < (self.port_start+1) or port_num > (self.port_end+1):
            return False

        # cpld info from "CPLD Register for es5800A2.2(V1.1)"
        cpld_map = {0: '0x82', 1: '0x83', 2: '0x84',
                    3: '0x85', 4: '0x86', 5: '0x87', 6: '0x8E'}
        cpld_key = (port_num - 1)/8
        cpld_mask = (1 << (port_num - 1) % 8)

        # use i2cget cmd to get cpld data
        output = os.popen('i2cdetect -l | grep CP')
        bus_num = output.read()[4]
        cmd = "i2cget -y "+bus_num+" 0x5 "+cpld_map[cpld_key]
        tmp = os.popen(cmd).read().replace("\n", "")
        cpld_value = int(tmp, 16)

        if cpld_value & cpld_mask == 0:
            return True
        else:
            return False

    def get_low_power_mode(self, port_num):
        '''
        # Check for invalid port_num
        if port_num < self.port_start or port_num > self.port_end:
            return False

        try:
            reg_file = open("/sys/devices/platform/dell-s6000-cpld.0/qsfp_lpmode")
        except IOError as e:
            print "Error: unable to open file: %s" % str(e)

        content = reg_file.readline().rstrip()

        # content is a string containing the hex representation of the register
        reg_value = int(content, 16)

        # Mask off the bit corresponding to our port
        mask = (1 << port_num)

        # LPMode is active high
        if reg_value & mask == 0:
            return False
        '''
        return False

    def set_low_power_mode(self, port_num, lpmode):
        # Check for invalid port_num
        if port_num < self.port_start or port_num > self.port_end:
            return False

        try:
            reg_file = open(
                "/sys/devices/platform/dell-s6000-cpld.0/qsfp_lpmode", "r+")
        except IOError as e:
            print("Error: unable to open file: %s" % str(e))
            return False

        content = reg_file.readline().rstrip()

        # content is a string containing the hex representation of the register
        reg_value = int(content, 16)

        # Mask off the bit corresponding to our port
        mask = (1 << port_num)

        # LPMode is active high; set or clear the bit accordingly
        if lpmode is True:
            reg_value = reg_value | mask
        else:
            reg_value = reg_value & ~mask

        # Convert our register value back to a hex string and write back
        content = hex(reg_value)

        reg_file.seek(0)
        reg_file.write(content)
        reg_file.close()

        return True

    def reset(self, port_num):
        QSFP_RESET_REGISTER_DEVICE_FILE = "/sys/devices/platform/dell-s6000-cpld.0/qsfp_reset"

        # Check for invalid port_num
        if port_num < self.port_start or port_num > self.port_end:
            return False

        try:
            reg_file = open(QSFP_RESET_REGISTER_DEVICE_FILE, "r+")
        except IOError as e:
            print("Error: unable to open file: %s" % str(e))
            return False

        content = reg_file.readline().rstrip()

        # File content is a string containing the hex representation of the register
        reg_value = int(content, 16)

        # Mask off the bit corresponding to our port
        mask = (1 << port_num)

        # ResetL is active low
        reg_value = reg_value & ~mask

        # Convert our register value back to a hex string and write back
        reg_file.seek(0)
        reg_file.write(hex(reg_value))
        reg_file.close()

        # Sleep 1 second to allow it to settle
        time.sleep(1)

        # Flip the bit back high and write back to the register to take port out of reset
        try:
            reg_file = open(QSFP_RESET_REGISTER_DEVICE_FILE, "w")
        except IOError as e:
            print("Error: unable to open file: %s" % str(e))
            return False

        reg_value = reg_value | mask
        reg_file.seek(0)
        reg_file.write(hex(reg_value))
        reg_file.close()

        return True

    def get_transceiver_change_event(self):
        """
        TODO: This function need to be implemented
        when decide to support monitoring SFP(Xcvrd)
        on this platform.
        """
        raise NotImplementedError