#
# -*- coding: utf-8 -*-
# Copyright 2019 Red Hat
# GNU General Public License v3.0+
# (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
"""
The exos_vlans class
It is in this file where the current configuration (as dict)
is compared to the provided configuration (as dict) and the command set
necessary to bring the current configuration to it's desired end-state is
created
"""
from __future__ import absolute_import, division, print_function
__metaclass__ = type

import json
from copy import deepcopy
from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.cfg.base import ConfigBase
from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.utils import to_list, dict_diff
from ansible_collections.community.general.plugins.module_utils.network.exos.facts.facts import Facts
from ansible_collections.community.general.plugins.module_utils.network.exos.exos import send_requests
from ansible_collections.community.general.plugins.module_utils.network.exos.utils.utils import search_obj_in_list


class Vlans(ConfigBase):
    """
    The exos_vlans class
    """

    gather_subset = [
        '!all',
        '!min',
    ]

    gather_network_resources = [
        'vlans',
    ]

    VLAN_POST = {
        "data": {"openconfig-vlan:vlans": []},
        "method": "POST",
        "path": "/rest/restconf/data/openconfig-vlan:vlans/"
    }

    VLAN_PATCH = {
        "data": {"openconfig-vlan:vlans": {"vlan": []}},
        "method": "PATCH",
        "path": "/rest/restconf/data/openconfig-vlan:vlans/"
    }

    VLAN_DELETE = {
        "method": "DELETE",
        "path": None
    }

    DEL_PATH = "/rest/restconf/data/openconfig-vlan:vlans/vlan="

    REQUEST_BODY = {
        "config": {"name": None, "status": "ACTIVE", "tpid": "oc-vlan-types:TPID_0x8100", "vlan-id": None}
    }

    def __init__(self, module):
        super(Vlans, self).__init__(module)

    def get_vlans_facts(self):
        """ Get the 'facts' (the current configuration)

        :rtype: A dictionary
        :returns: The current configuration as a dictionary
        """
        facts, _warnings = Facts(self._module).get_facts(
            self.gather_subset, self.gather_network_resources)
        vlans_facts = facts['ansible_network_resources'].get('vlans')
        if not vlans_facts:
            return []
        return vlans_facts

    def execute_module(self):
        """ Execute the module

        :rtype: A dictionary
        :returns: The result from module execution
        """
        result = {'changed': False}
        warnings = list()
        requests = list()

        existing_vlans_facts = self.get_vlans_facts()
        requests.extend(self.set_config(existing_vlans_facts))
        if requests:
            if not self._module.check_mode:
                send_requests(self._module, requests=requests)
            result['changed'] = True
        result['requests'] = requests

        changed_vlans_facts = self.get_vlans_facts()

        result['before'] = existing_vlans_facts
        if result['changed']:
            result['after'] = changed_vlans_facts

        result['warnings'] = warnings
        return result

    def set_config(self, existing_vlans_facts):
        """ Collect the configuration from the args passed to the module,
            collect the current configuration (as a dict from facts)

        :rtype: A list
        :returns: the requests necessary to migrate the current configuration
                  to the desired configuration
        """
        want = self._module.params['config']
        have = existing_vlans_facts
        resp = self.set_state(want, have)
        return to_list(resp)

    def set_state(self, want, have):
        """ Select the appropriate function based on the state provided

        :param want: the desired configuration as a dictionary
        :param have: the current configuration as a dictionary
        :rtype: A list
        :returns: the requests necessary to migrate the current configuration
                  to the desired configuration
        """
        state = self._module.params['state']
        if state == 'overridden':
            requests = self._state_overridden(want, have)
        elif state == 'deleted':
            requests = self._state_deleted(want, have)
        elif state == 'merged':
            requests = self._state_merged(want, have)
        elif state == 'replaced':
            requests = self._state_replaced(want, have)
        return requests

    def _state_replaced(self, want, have):
        """ The request generator when state is replaced

        :rtype: A list
        :returns: the requests necessary to migrate the current configuration
                  to the desired configuration
        """
        requests = []
        request_patch = deepcopy(self.VLAN_PATCH)

        for w in want:
            if w.get('vlan_id'):
                h = search_obj_in_list(w['vlan_id'], have, 'vlan_id')
                if h:
                    if dict_diff(w, h):
                        request_body = self._update_patch_request(w)
                        request_patch["data"]["openconfig-vlan:vlans"]["vlan"].append(request_body)
                else:
                    request_post = self._update_post_request(w)
                    requests.append(request_post)

        if len(request_patch["data"]["openconfig-vlan:vlans"]["vlan"]):
            request_patch["data"] = json.dumps(request_patch["data"])
            requests.append(request_patch)

        return requests

    def _state_overridden(self, want, have):
        """ The request generator when state is overridden

        :rtype: A list
        :returns: the requests necessary to migrate the current configuration
                  to the desired configuration
        """
        requests = []
        request_patch = deepcopy(self.VLAN_PATCH)

        have_copy = []
        for w in want:
            if w.get('vlan_id'):
                h = search_obj_in_list(w['vlan_id'], have, 'vlan_id')
                if h:
                    if dict_diff(w, h):
                        request_body = self._update_patch_request(w)
                        request_patch["data"]["openconfig-vlan:vlans"]["vlan"].append(request_body)
                    have_copy.append(h)
                else:
                    request_post = self._update_post_request(w)
                    requests.append(request_post)

        for h in have:
            if h not in have_copy and h['vlan_id'] != 1:
                request_delete = self._update_delete_request(h)
                requests.append(request_delete)

        if len(request_patch["data"]["openconfig-vlan:vlans"]["vlan"]):
            request_patch["data"] = json.dumps(request_patch["data"])
            requests.append(request_patch)

        return requests

    def _state_merged(self, want, have):
        """ The requests generator when state is merged

        :rtype: A list
        :returns: the requests necessary to merge the provided into
                  the current configuration
        """
        requests = []

        request_patch = deepcopy(self.VLAN_PATCH)

        for w in want:
            if w.get('vlan_id'):
                h = search_obj_in_list(w['vlan_id'], have, 'vlan_id')
                if h:
                    if dict_diff(w, h):
                        request_body = self._update_patch_request(w)
                        request_patch["data"]["openconfig-vlan:vlans"]["vlan"].append(request_body)
                else:
                    request_post = self._update_post_request(w)
                    requests.append(request_post)

        if len(request_patch["data"]["openconfig-vlan:vlans"]["vlan"]):
            request_patch["data"] = json.dumps(request_patch["data"])
            requests.append(request_patch)
        return requests

    def _state_deleted(self, want, have):
        """ The requests generator when state is deleted

        :rtype: A list
        :returns: the requests necessary to remove the current configuration
                  of the provided objects
        """
        requests = []

        if want:
            for w in want:
                if w.get('vlan_id'):
                    h = search_obj_in_list(w['vlan_id'], have, 'vlan_id')
                    if h:
                        request_delete = self._update_delete_request(h)
                        requests.append(request_delete)

        else:
            if not have:
                return requests
            for h in have:
                if h['vlan_id'] == 1:
                    continue
                else:
                    request_delete = self._update_delete_request(h)
                    requests.append(request_delete)

        return requests

    def _update_vlan_config_body(self, want, request):
        request["config"]["name"] = want["name"]
        request["config"]["status"] = "SUSPENDED" if want["state"] == "suspend" else want["state"].upper()
        request["config"]["vlan-id"] = want["vlan_id"]
        return request

    def _update_patch_request(self, want):
        request_body = deepcopy(self.REQUEST_BODY)
        request_body = self._update_vlan_config_body(want, request_body)
        return request_body

    def _update_post_request(self, want):
        request_post = deepcopy(self.VLAN_POST)
        request_body = deepcopy(self.REQUEST_BODY)
        request_body = self._update_vlan_config_body(want, request_body)
        request_post["data"]["openconfig-vlan:vlans"].append(request_body)
        request_post["data"] = json.dumps(request_post["data"])
        return request_post

    def _update_delete_request(self, have):
        request_delete = deepcopy(self.VLAN_DELETE)
        request_delete["path"] = self.DEL_PATH + str(have['vlan_id'])
        return request_delete