# Copyright (c) 2014  Kontron Europe GmbH
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA

from .msgs import create_request_by_name
from .utils import check_rsp_completion_code, ByteBuffer

LAN_PARAMETER_SET_IN_PROGRESS = 0
LAN_PARAMETER_AUTHENTICATION_TYPE_SUPPORT = 1
LAN_PARAMETER_AUTHENTICATION_TYPE_ENABLE = 2
LAN_PARAMETER_IP_ADDRESS = 3
LAN_PARAMETER_IP_ADDRESS_SOURCE = 4
LAN_PARAMETER_MAC_ADDRESS = 5
LAN_PARAMETER_SUBNET_MASK = 6
LAN_PARAMETER_IPV4_HEADER_PARAMETERS = 7
LAN_PARAMETER_PRIMARY_RMCP_PORT = 8
LAN_PARAMETER_SECONDARY_RMCP_PORT = 9
LAN_PARAMETER_BMC_GENERATED_ARP_CONTROL = 10
LAN_PARAMETER_GRATUITOUS_ARP_INTERVAL = 11
LAN_PARAMETER_DEFAULT_GATEWAY_ADDRESS = 12
LAN_PARAMETER_DEFAULT_GATEWAY_MAC_ADDRESS = 13
LAN_PARAMETER_BACKUP_GATEWAY_ADDRESS = 14
LAN_PARAMETER_BACKUP_GATEWAY_MAC_ADDRESS = 15
LAN_PARAMETER_COMMUNITY_STRING = 16
LAN_PARAMETER_NUMBER_OF_DESTINATIONS = 17
LAN_PARAMETER_DESTINATION_TYPE = 18
LAN_PARAMETER_DESTINATION_ADDRESSES = 19
# following parameters are introduced with IPMI v2.0/RMCP+
LAN_PARAMETER_802_1Q_VLAN_ID = 20
LAN_PARAMETER_802_1Q_VLAN_PRIORITY = 21
LAN_PARAMETER_RMCP_PLUS_MESSAGING_CIPHER_SUITE_ENTRY_SUPPORT = 22
LAN_PARAMETER_RMCP_PLUS__MESSAGING_CIPHER_SUITE_ENTRIES = 23
LAN_PARAMETER_RMCP_PLUS_MESSAGING_CIPHER_SUITE_PRIVILEGE_LEVES = 24
LAN_PARAMETER_DESTINATION_ADDRESS_VLAN_TAGS = 25

LAN_PARAMETER_IP_ADDRESS_SOURCE_UNSPECIFIED = 0
LAN_PARAMETER_IP_ADDRESS_SOURCE_STATIC = 1
LAN_PARAMETER_IP_ADDRESS_SOURCE_DHCP = 2
LAN_PARAMETER_IP_ADDRESS_SOURCE_BIOS_OR_SYSTEM_SOFTWARE = 3
LAN_PARAMETER_IP_ADDRESS_SOURCE_BMC_OTHER_PROTOCOL = 4

CONVERT_RAW_TO_IP_SRC = {
    0: "unknown",
    1: "static",
    2: "dhcp",
    3: "bios",
    4: "other"
}


def data_to_ip_address(data):
    """
    Convert a `GetLanConfigurationParameters(LAN_PARAMETER_IP_ADDRESS)` response
    data into the string representation of the encoded ip address,
    in format xxx.xxx.xxx.xxx .
    """
    return '.'.join(map(str, data))


def ip_address_to_data(ip_address):
    """
    Convert an ip address (string) into a
    `SetLanConfigurationParameters(LAN_PARAMETER_IP_ADDRESS)` request data.
    """
    return ByteBuffer(map(int, ip_address.split('.')))


def data_to_ip_source(data):
    """
    Convert a `GetLanConfigurationParameters(LAN_PARAMETER_IP_ADDRESS_SOURCE)`
    response data into the string representation of the encoded ip source.
    """
    # The ip source is encoded in the last 4 bits of the response
    return CONVERT_RAW_TO_IP_SRC[data[0] & 0b1111]


def ip_source_to_data(ip_source):
    """
    Convert an ip source (string) into a
    `SetLanConfigurationParameters(LAN_PARAMETER_IP_ADDRESS_SOURCE)` request data.
    """
    if ip_source == "dhcp":
        data = ByteBuffer([2])
    elif ip_source == "static":
        data = ByteBuffer([1])
    else:
        raise ValueError(f"Unknown value for ip_source argument: {ip_source}. Possible values are: dhcp, static.")
    return data


def data_to_mac_address(data):
    """
    Convert a `GetLanConfigurationParameters(LAN_PARAMETER_MAC_ADDRESS)` response
    data into the string representation of the encoded mac address,
    in format aa:bb:cc:dd:ee:ff .
    """
    return ':'.join([f"{i:02x}" for i in data])


def data_to_vlan(data):
    """
    Convert a `GetLanConfigurationParameters(LAN_PARAMETER_802_1Q_VLAN_ID)` response
    data into an integer representation of the encoded vlan.

    A disabled VLAN will return a VLAN ID = 0
    """
    # Check if the vlan is enabled. We return vlan = 0 for a disabled vlan as a
    # convention.
    if data[1] >> 7 == 0:
        return 0

    # The vlan ID must be extracted from the response, according to IPMI
    # specification.
    #
    #   Example with VLAN ID = 394
    #   The raw response to `get_lan_config_param` will be [138, 129]
    #   The binary representation will be :
    #
    #       |    data[0]   |  |    data[1]   |
    # Rsp : 1 0 0 0  1 0 1 0  1 0 0 0  0 0 0 1
    #       ^              ^           ^     ^
    #       |--------------|           |-----|
    #       |least sign. bits          |most sign. bits
    #
    # By rearranging the bits order, we get the VLAN value :
    #       0 0 0 0  0 0 0 1  1 0 0 0  1 0 1 0 = 394
    return ((data[1] & 0b1111) << 8) | data[0]


def vlan_to_data(vlan):
    """
    Convert a vlan (int) into a
    `SetLanConfigurationParameters(LAN_PARAMETER_802_1Q_VLAN_ID)` request data.
    """
    if not isinstance(vlan, int):
        raise TypeError(f"Wrong type for vlan argument: {type(vlan)}, expected int.")
    elif vlan > 4095:
        raise ValueError(f"Wrong value for vlan argument: {vlan}. It cannot be greater than 4095.")

    if vlan == 0:
        # We want to deactivate the vlan (no vlan)
        data = ByteBuffer([0, 0])
    else:
        # We want to set the vlan ID
        # first separate the two bytes of the vlan
        least_sign_byte = vlan & 0b11111111
        most_sign_byte = (vlan >> 8) & 0b1111
        # then create the vlan enabled bit
        vlan_enable = 0b10000000
        # finally we concatenate every byte together
        data = ByteBuffer([least_sign_byte, vlan_enable | most_sign_byte])
    return data


class Lan(object):
    def get_lan_config_param(self, channel=0, parameter_selector=0,
                             set_selector=0, block_selector=0,
                             revision_only=0):
        req = create_request_by_name('GetLanConfigurationParameters')
        req.command.get_parameter_revision_only = revision_only
        if revision_only != 1:
            req.command.channel_number = channel
            req.parameter_selector = parameter_selector
            req.set_selector = set_selector
            req.block_selector = block_selector
        rsp = self.send_message(req)
        check_rsp_completion_code(rsp)
        return rsp.data

    def set_lan_config_param(self, channel,
                             parameter_selector, data):
        req = create_request_by_name('SetLanConfigurationParameters')
        req.command.channel_number = channel
        req.parameter_selector = parameter_selector
        req.data = data
        rsp = self.send_message(req)
        check_rsp_completion_code(rsp)

    def get_ip_address(self, channel=0):
        """
        Return a string representing the ip address of the device, in format xxx.xxx.xxx.xxx
        """
        ip_address_raw = self.get_lan_config_param(channel, LAN_PARAMETER_IP_ADDRESS)
        return data_to_ip_address(ip_address_raw)

    def set_ip_address(self, ip_address, channel=0):
        """
        WARNING: changing the IP address of the BMC will make a current
        lan session unusable because it still has the former IP address.

        Be sure to open a new session with the new IP for future calls if
        using a lan interface.
        """
        data = ip_address_to_data(ip_address)
        self.set_lan_config_param(channel, LAN_PARAMETER_IP_ADDRESS, data)

    def get_ip_source(self, channel=0):
        """
        Return a string representing the ip source of the device.

        Possible values are listed in `CONVERT_RAW_TO_IP_SRC` variable.
        """
        ip_source_raw = self.get_lan_config_param(channel, LAN_PARAMETER_IP_ADDRESS_SOURCE)
        return data_to_ip_source(ip_source_raw)

    def set_ip_source(self, ip_source, channel=0):
        """
        WARNING: changing the IP source may change the IP address of the BMC,
        which will make a current lan session unusable because it still has
        the former IP address.

        Be sure to open a new session with the new IP for future calls if
        using a lan interface.
        """
        data = ip_source_to_data(ip_source)
        self.set_lan_config_param(channel, LAN_PARAMETER_IP_ADDRESS_SOURCE, data)

    def get_mac_address(self, channel=0):
        """
        Return a string representing the mac address of the device, in format aa:bb:cc:dd:ee:ff.
        """
        mac_address_raw = self.get_lan_config_param(channel, LAN_PARAMETER_MAC_ADDRESS)
        return data_to_mac_address(mac_address_raw)

    def get_vlan_id(self, channel=0):
        """
        Return the 802.1q VLAN ID of the device.
        """
        vlan_id_raw = self.get_lan_config_param(channel, LAN_PARAMETER_802_1Q_VLAN_ID)
        return data_to_vlan(vlan_id_raw)

    def set_vlan_id(self, vlan, channel=0):
        """
        WARNING: changing the VLAN ID may change the IP address of the BMC
        depending on your current network configuration.
        This could make a current lan session unusable because it still has
        the former IP address.

        Be sure to open a new session with the new IP for future calls if
        using a lan interface.
        """
        data = vlan_to_data(vlan)
        self.set_lan_config_param(channel, LAN_PARAMETER_802_1Q_VLAN_ID, data)


class LanParameter(object):
    pass