#!/usr/bin/python
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
#

DOCUMENTATION = '''
---

module: nxos_interface
version_added: "2.1"
short_description: Manages physical attributes of interfaces
description:
    - Manages physical attributes of interfaces of NX-OS switches
author: Jason Edelman (@jedelman8)
notes:
    - This module is also used to create logical interfaces such as
      svis and loopbacks.
    - Be cautious of platform specific idiosyncrasies. For example,
      when you default a loopback interface, the admin state toggles
      on certain versions of NX-OS.
options:
    interface:
        description:
            - Full name of interface, i.e. Ethernet1/1, port-channel10.
        required: true
        default: null
    admin_state:
        description:
            - Administrative state of the interface.
        required: false
        default: up
        choices: ['up','down']
    description:
        description:
            - Interface description.
        required: false
        default: null
    mode:
        description:
            - Manage I(Layer2) or I(Layer3) state of the interface.
        required: false
        default: null
        choices: ['layer2','layer3']
    state:
        description:
            - Specify desired state of the resource.
        required: true
        default: present
        choices: ['present','absent','default']
'''

EXAMPLES = '''
# Ensure an interface is a Layer 3 port and that it has the proper description
- nxos_interface: interface=Ethernet1/1 description='Configured by Ansible' mode=layer3 host={{ inventory_hostname }}

# Admin down an interface
- nxos_interface: interface=Ethernet2/1 host={{ inventory_hostname }} admin_state=down

# Remove all loopback interfaces
- nxos_interface: interface=loopback state=absent host={{ inventory_hostname }}

# Remove all logical interfaces
- nxos_interface: interface={{ item }} state=absent host={{ inventory_hostname }}
  with_items:
    - loopback
    - portchannel
    - svi

# Admin up all ethernet interfaces
- nxos_interface: interface=ethernet host={{ inventory_hostname }} admin_state=up

# Admin down ALL interfaces (physical and logical)
- nxos_interface: interface=all host={{ inventory_hostname }} admin_state=down

'''
RETURN = '''

proposed:
    description: k/v pairs of parameters passed into module
    returned: always
    type: dict
    sample: {"admin_state": "down"}
existing:
    description: k/v pairs of existing switchport
    type: dict
    sample:  {"admin_state": "up", "description": "None", "interface": "port-channel101", "mode": "layer2", "type": "portchannel"}
end_state:
    description: k/v pairs of switchport after module execution
    returned: always
    type: dict or null
    sample:  {"admin_state": "down", "description": "None", "interface": "port-channel101", "mode": "layer2", "type": "portchannel"}
state:
    description: state as sent in from the playbook
    returned: always
    type: string
    sample: "present"
updates:
    description: command list sent to the device
    returned: always
    type: list
    sample: ["interface port-channel101", "shutdown"]
changed:
    description: check to see if a change was made on the device
    returned: always
    type: boolean
    sample: true

'''


def is_default_interface(interface, module):
    """Checks to see if interface exists and if it is a default config

    Args:
        interface (str): full name of interface, i.e. vlan10,
            Ethernet1/1, loopback10

    Returns:
        True: if interface has default config
        False: if it does not have a default config
        DNE (str): if the interface does not exist - loopbacks, SVIs, etc.

    """
    command = 'show run interface ' + interface

    try:
        body = execute_show_command(command, module,
                                    command_type='cli_show_ascii')[0]
        # module.exit_json(abcd='asdasdfasdf', body=body, c=command)
    except IndexError:
        body = []

    if body:
        raw_list = body.split('\n')
        found = False
        for line in raw_list:
            if line.startswith('interface'):
                found = True
            if found and line and not line.startswith('interface'):
                return False
        return True

    else:
        return 'DNE'


def get_interface_type(interface):
    """Gets the type of interface

    Args:
        interface (str): full name of interface, i.e. Ethernet1/1, loopback10,
            port-channel20, vlan20

    Returns:
        type of interface: ethernet, svi, loopback, management, portchannel,
         or unknown

    """
    if interface.upper().startswith('ET'):
        return 'ethernet'
    elif interface.upper().startswith('VL'):
        return 'svi'
    elif interface.upper().startswith('LO'):
        return 'loopback'
    elif interface.upper().startswith('MG'):
        return 'management'
    elif interface.upper().startswith('MA'):
        return 'management'
    elif interface.upper().startswith('PO'):
        return 'portchannel'
    else:
        return 'unknown'


def get_manual_interface_attributes(interface, module):
    """Gets admin state and description of a SVI interface. Hack due to API.

    Args:
        interface (str): full name of SVI interface, i.e. vlan10

    Returns:
        dictionary that has two k/v pairs: admin_state & description
            if not an svi, returns None

    """

    if get_interface_type(interface) == 'svi':
        command = 'show interface ' + interface
        try:
            body = execute_modified_show_for_cli_text(command, module)[0]
        except (IndexError, ShellError):
            return None

        command_list = body.split('\n')
        desc = None
        admin_state = 'up'
        for each in command_list:
            if 'Description:' in each:
                line = each.split('Description:')
                desc = line[1].strip().split('MTU')[0].strip()
            elif 'Administratively down' in each:
                admin_state = 'down'

        return dict(description=desc, admin_state=admin_state)
    else:
        return None


def get_interface(intf, module):
    """Gets current config/state of interface

    Args:
        intf (string): full name of interface, i.e. Ethernet1/1, loopback10,
            port-channel20, vlan20

    Returns:
      dictionary that has relevant config/state data about the given
          interface based on the type of interface it is

    """
    base_key_map = {
        'interface': 'interface',
        'admin_state': 'admin_state',
        'desc': 'description',
    }
    mode_map = {
        'eth_mode': 'mode'
    }
    loop_map = {
        'state': 'admin_state'
    }
    svi_map = {
        'svi_admin_state': 'admin_state',
        'desc': 'description'
    }
    mode_value_map = {
        "mode": {
            "access": "layer2",
            "trunk": "layer2",
            "routed": "layer3",
            "layer3": "layer3"
        }
    }

    key_map = {}
    interface = {}

    command = 'show interface ' + intf
    try:
        body = execute_show_command(command, module)[0]
    except IndexError:
        body = []

    if body:
        interface_table = body['TABLE_interface']['ROW_interface']

        intf_type = get_interface_type(intf)
        if intf_type in ['portchannel', 'ethernet']:
            if not interface_table.get('eth_mode'):
                interface_table['eth_mode'] = 'layer3'

        if intf_type == 'ethernet':
            key_map.update(base_key_map)
            key_map.update(mode_map)
            temp_dict = apply_key_map(key_map, interface_table)
            temp_dict = apply_value_map(mode_value_map, temp_dict)
            interface.update(temp_dict)

        elif intf_type == 'svi':
            key_map.update(svi_map)
            temp_dict = apply_key_map(key_map, interface_table)
            interface.update(temp_dict)
            attributes = get_manual_interface_attributes(intf, module)
            interface['admin_state'] = str(attributes.get('admin_state',
                                                          'nxapibug'))
            interface['description'] = str(attributes.get('description',
                                                          'nxapi_bug'))
        elif intf_type == 'loopback':
            key_map.update(base_key_map)
            key_map.pop('admin_state')
            key_map.update(loop_map)
            temp_dict = apply_key_map(key_map, interface_table)
            if not temp_dict.get('description'):
                temp_dict['description'] = "None"
            interface.update(temp_dict)

        elif intf_type == 'management':
            key_map.update(base_key_map)
            temp_dict = apply_key_map(key_map, interface_table)
            interface.update(temp_dict)

        elif intf_type == 'portchannel':
            key_map.update(base_key_map)
            key_map.update(mode_map)
            temp_dict = apply_key_map(key_map, interface_table)
            temp_dict = apply_value_map(mode_value_map, temp_dict)
            if not temp_dict.get('description'):
                temp_dict['description'] = "None"
            interface.update(temp_dict)

    interface['type'] = intf_type

    return interface


def get_intf_args(interface):
    intf_type = get_interface_type(interface)

    arguments = ['admin_state', 'description']

    if intf_type in ['ethernet', 'portchannel']:
        arguments.extend(['mode'])

    return arguments


def get_interfaces_dict(module):
    """Gets all active interfaces on a given switch

    Returns:
        dictionary with interface type (ethernet,svi,loop,portchannel) as the
            keys.  Each value is a list of interfaces of given interface (key)
            type.

    """
    command = 'show interface status'
    try:
        body = execute_show_command(command, module)[0]
    except IndexError:
        body = {}

    interfaces = {
        'ethernet': [],
        'svi': [],
        'loopback': [],
        'management': [],
        'portchannel': [],
        'unknown': []
        }

    interface_list = body.get('TABLE_interface')['ROW_interface']
    for i in interface_list:
        intf = i['interface']
        intf_type = get_interface_type(intf)

        interfaces[intf_type].append(intf)

    return interfaces


def normalize_interface(if_name):
    """Return the normalized interface name
    """
    def _get_number(if_name):
        digits = ''
        for char in if_name:
            if char.isdigit() or char == '/':
                digits += char
        return digits

    if if_name.lower().startswith('et'):
        if_type = 'Ethernet'
    elif if_name.lower().startswith('vl'):
        if_type = 'Vlan'
    elif if_name.lower().startswith('lo'):
        if_type = 'loopback'
    elif if_name.lower().startswith('po'):
        if_type = 'port-channel'
    else:
        if_type = None

    number_list = if_name.split(' ')
    if len(number_list) == 2:
        number = number_list[-1].strip()
    else:
        number = _get_number(if_name)

    if if_type:
        proper_interface = if_type + number
    else:
        proper_interface = if_name

    return proper_interface


def apply_key_map(key_map, table):
    new_dict = {}
    for key, value in table.items():
        new_key = key_map.get(key)
        if new_key:
            value = table.get(key)
            if value:
                new_dict[new_key] = str(value)
            else:
                new_dict[new_key] = value
    return new_dict


def apply_value_map(value_map, resource):
    for key, value in value_map.items():
        resource[key] = value[resource.get(key)]
    return resource


def get_interface_config_commands(interface, intf, existing):
    """Generates list of commands to configure on device

    Args:
        interface (str): k/v pairs in the form of a set that should
            be configured on the device
        intf (str): full name of interface, i.e. Ethernet1/1

    Returns:
      list: ordered list of commands to be sent to device

    """

    commands = []

    desc = interface.get('description')
    if desc:
        commands.append('description {0}'.format(desc))

    mode = interface.get('mode')
    if mode:
        if mode == 'layer2':
            command = 'switchport'
        elif mode == 'layer3':
            command = 'no switchport'
        commands.append(command)

    admin_state = interface.get('admin_state')
    if admin_state:
        command = get_admin_state(interface, intf, admin_state)
        commands.append(command)

    if commands:
        commands.insert(0, 'interface ' + intf)

    return commands


def get_admin_state(interface, intf, admin_state):
    if admin_state == 'up':
        command = 'no shutdown'
    elif admin_state == 'down':
        command = 'shutdown'
    return command


def get_proposed(existing, normalized_interface, args):

    # gets proper params that are allowed based on interface type
    allowed_params = get_intf_args(normalized_interface)

    proposed = {}

    # retrieves proper interface params from args (user defined params)
    for param in allowed_params:
        temp = args.get(param)
        if temp:
            proposed[param] = temp

    return proposed


def smart_existing(module, intf_type, normalized_interface):

    # 7K BUG MAY CAUSE THIS TO FAIL

    all_interfaces = get_interfaces_dict(module)
    if normalized_interface in all_interfaces[intf_type]:
        existing = get_interface(normalized_interface, module)
        is_default = is_default_interface(normalized_interface, module)
    else:
        if intf_type == 'ethernet':
            module.fail_json(msg='Invalid Ethernet interface provided.',
                             interface=normalized_interface)
        elif intf_type in ['loopback', 'portchannel', 'svi']:
            existing = {}
            is_default = 'DNE'
    return existing, is_default


def execute_config_command(commands, module):
    try:
        module.configure(commands)
    except ShellError:
        clie = get_exception()
        module.fail_json(msg='Error sending CLI commands',
                         error=str(clie), commands=commands)


def get_cli_body_ssh(command, response, module):
    """Get response for when transport=cli.  This is kind of a hack and mainly
    needed because these modules were originally written for NX-API.  And
    not every command supports "| json" when using cli/ssh.  As such, we assume
    if | json returns an XML string, it is a valid command, but that the
    resource doesn't exist yet.
    """
    if 'xml' in response[0]:
        body = []
    elif 'show run' in command:
        body = response
    else:
        try:
            body = [json.loads(response[0])]
        except ValueError:
            module.fail_json(msg='Command does not support JSON output',
                             command=command)
    return body


def execute_show(cmds, module, command_type=None):
    try:
        if command_type:
            response = module.execute(cmds, command_type=command_type)
        else:
            response = module.execute(cmds)
    except ShellError:
        clie = get_exception()
        module.fail_json(msg='Error sending {0}'.format(command),
                         error=str(clie))
    return response


def execute_show_command(command, module, command_type='cli_show'):

    if module.params['transport'] == 'cli':
        command += ' | json'
        cmds = [command]
        response = execute_show(cmds, module)
        body = get_cli_body_ssh(command, response, module)
    elif module.params['transport'] == 'nxapi':
        cmds = [command]
        body = execute_show(cmds, module, command_type=command_type)

    return body


def execute_modified_show_for_cli_text(command, module):
    cmds = [command]
    response = execute_show(cmds, module)
    body = response
    return body


def flatten_list(command_lists):
    flat_command_list = []
    for command in command_lists:
        if isinstance(command, list):
            flat_command_list.extend(command)
        else:
            flat_command_list.append(command)
    return flat_command_list


def main():

    argument_spec = dict(
        interface=dict(required=True,),
        admin_state=dict(default='up', choices=['up', 'down'], required=False),
        description=dict(required=False, default=None),
        mode=dict(choices=['layer2', 'layer3'], required=False),
        state=dict(choices=['absent', 'present', 'default'],
                   default='present', required=False)
    )
    module = get_module(argument_spec=argument_spec,
                        supports_check_mode=True)

    interface = module.params['interface'].lower()
    admin_state = module.params['admin_state']
    description = module.params['description']
    mode = module.params['mode']
    state = module.params['state']

    changed = False

    args = dict(interface=interface, admin_state=admin_state,
                description=description, mode=mode)

    intf_type = get_interface_type(interface)

    normalized_interface = normalize_interface(interface)

    if normalized_interface == 'Vlan1' and state == 'absent':
        module.fail_json(msg='ERROR: CANNOT REMOVE VLAN 1!')

    if intf_type == 'unknown':
        module.fail_json(
            msg='unknown interface type found-1',
            interface=interface)

    existing, is_default = smart_existing(module, intf_type, normalized_interface)
    proposed = get_proposed(existing, normalized_interface, args)

    delta = dict()
    commands = []

    if state == 'absent':
        if intf_type in ['svi', 'loopback', 'portchannel']:
            if is_default != 'DNE':
                cmds = ['no interface {0}'.format(normalized_interface)]
                commands.append(cmds)
        elif intf_type in ['ethernet']:
            if is_default is False:
                cmds = ['default interface {0}'.format(normalized_interface)]
                commands.append(cmds)
    elif state == 'present':
        if not existing:
            cmds = get_interface_config_commands(proposed,
                                                 normalized_interface,
                                                 existing)
            commands.append(cmds)
        else:
            delta = dict(set(proposed.iteritems()).difference(
                existing.iteritems()))
            if delta:
                cmds = get_interface_config_commands(delta,
                                                     normalized_interface,
                                                     existing)
                commands.append(cmds)
    elif state == 'default':
        if is_default is False:
            cmds = ['default interface {0}'.format(normalized_interface)]
            commands.append(cmds)
        elif is_default == 'DNE':
            module.exit_json(msg='interface you are trying to default does'
                             ' not exist')

    cmds = flatten_list(commands)

    end_state = existing

    if cmds:
        if module.check_mode:
            module.exit_json(changed=True, commands=cmds)
        else:
            execute_config_command(cmds, module)
            if delta.get('mode'): # or delta.get('admin_state'):
                # if the mode changes from L2 to L3, the admin state
                # seems to change after the API call, so adding a second API
                # call to ensure it's in the desired state.
                admin_state = delta.get('admin_state') or admin_state
                c1 = 'interface {0}'.format(normalized_interface)
                c2 = get_admin_state(delta, normalized_interface, admin_state)
                cmds2 = [c1, c2]
                execute_config_command(cmds2, module)
                cmds.extend(cmds2)
            changed = True
            end_state, is_default = smart_existing(module, intf_type,
                                                   normalized_interface)

    results = {}
    results['proposed'] = proposed
    results['existing'] = existing
    results['end_state'] = end_state
    results['state'] = state
    results['updates'] = cmds
    results['changed'] = changed

    module.exit_json(**results)

from ansible.module_utils.basic import *
from ansible.module_utils.urls import *
from ansible.module_utils.shell import *
from ansible.module_utils.netcfg import *
from ansible.module_utils.nxos import *

if __name__ == '__main__':
    main()