#!/usr/bin/python
#
# Copyright (c) 2018 Yunge Zhu, <yungez@microsoft.com>
#
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import absolute_import, division, print_function
__metaclass__ = type


ANSIBLE_METADATA = {'metadata_version': '1.1',
                    'status': ['preview'],
                    'supported_by': 'community'}


DOCUMENTATION = '''
---
module: azure_rm_appserviceplan
version_added: "2.7"
short_description: Manage App Service Plan
description:
    - Create, update and delete instance of App Service Plan.

options:
    resource_group:
        description:
            - Name of the resource group to which the resource belongs.
        required: True

    name:
        description:
            - Unique name of the app service plan to create or update.
        required: True

    location:
        description:
            - Resource location. If not set, location from the resource group will be used as default.

    sku:
        description:
            - The pricing tiers, e.g., F1, D1, B1, B2, B3, S1, P1, P1V2 etc.
            - Please see U(https://azure.microsoft.com/en-us/pricing/details/app-service/plans/) for more detail.
            - For linux app service plan, please see U(https://azure.microsoft.com/en-us/pricing/details/app-service/linux/) for more detail.

    is_linux:
        description:
            - Describe whether to host webapp on Linux worker.
        type: bool
        default: false

    number_of_workers:
        description:
            - Describe number of workers to be allocated.

    state:
      description:
        - Assert the state of the app service plan.
        - Use 'present' to create or update an app service plan and 'absent' to delete it.
      default: present
      choices:
        - absent
        - present

extends_documentation_fragment:
    - azure
    - azure_tags

author:
    - "Yunge Zhu(@yungezz)"

'''

EXAMPLES = '''
    - name: Create a windows app service plan
      azure_rm_appserviceplan:
        name: "windowsplan1"
        resource_group: "appserviceplan_rg"
        location: "eastus"
        sku: S1

    - name: Create a linux app service plan
      azure_rm_appserviceplan:
        resource_group: "appserviceplan_rg"
        name: "linuxplan1"
        location: "eastus"
        sku: S1
        is_linux: true
        number_of_workers: 1

    - name: update sku of existing windows app service plan
      azure_rm_appserviceplan:
        name: "windowsplan2"
        resource_group: "appserviceplan_rg"
        location: "eastus"
        sku: S2
'''

RETURN = '''
azure_appserviceplan:
    description: Facts about the current state of the app service plan
    returned: always
    type: dict
    sample: {
            "id": "/subscriptions/<subs_id>/resourceGroups/ansiblewebapp1_plan/providers/Microsoft.Web/serverfarms/win_appplan11"
    }
'''

import time
from ansible.module_utils.azure_rm_common import AzureRMModuleBase

try:
    from msrestazure.azure_exceptions import CloudError
    from msrestazure.azure_operation import AzureOperationPoller
    from msrest.serialization import Model
    from azure.mgmt.web.models import (
        app_service_plan, AppServicePlan, SkuDescription
    )
except ImportError:
    # This is handled in azure_rm_common
    pass


def _normalize_sku(sku):
    if sku is None:
        return sku

    sku = sku.upper()
    if sku == 'FREE':
        return 'F1'
    elif sku == 'SHARED':
        return 'D1'
    return sku


def get_sku_name(tier):
    tier = tier.upper()
    if tier == 'F1' or tier == "FREE":
        return 'FREE'
    elif tier == 'D1' or tier == "SHARED":
        return 'SHARED'
    elif tier in ['B1', 'B2', 'B3', 'BASIC']:
        return 'BASIC'
    elif tier in ['S1', 'S2', 'S3']:
        return 'STANDARD'
    elif tier in ['P1', 'P2', 'P3']:
        return 'PREMIUM'
    elif tier in ['P1V2', 'P2V2', 'P3V2']:
        return 'PREMIUMV2'
    else:
        return None


class AzureRMAppServicePlans(AzureRMModuleBase):
    """Configuration class for an Azure RM App Service Plan resource"""

    def __init__(self):
        self.module_arg_spec = dict(
            resource_group=dict(
                type='str',
                required=True
            ),
            name=dict(
                type='str',
                required=True
            ),
            location=dict(
                type='str'
            ),
            sku=dict(
                type='str'
            ),
            is_linux=dict(
                type='bool',
                default=False
            ),
            number_of_workers=dict(
                type='str'
            ),
            state=dict(
                type='str',
                default='present',
                choices=['present', 'absent']
            )
        )

        self.resource_group = None
        self.name = None
        self.location = None

        self.sku = None
        self.is_linux = None
        self.number_of_workers = 1

        self.tags = None

        self.results = dict(
            changed=False,
            ansible_facts=dict(azure_appserviceplan=None)
        )
        self.state = None

        super(AzureRMAppServicePlans, self).__init__(derived_arg_spec=self.module_arg_spec,
                                                     supports_check_mode=True,
                                                     supports_tags=True)

    def exec_module(self, **kwargs):
        """Main module execution method"""

        for key in list(self.module_arg_spec.keys()) + ['tags']:
            if kwargs[key]:
                setattr(self, key, kwargs[key])

        old_response = None
        response = None
        to_be_updated = False

        # set location
        resource_group = self.get_resource_group(self.resource_group)
        if not self.location:
            self.location = resource_group.location

        # get app service plan
        old_response = self.get_plan()

        # if not existing
        if not old_response:
            self.log("App Service plan doesn't exist")

            if self.state == "present":
                to_be_updated = True

                if not self.sku:
                    self.fail('Please specify sku in plan when creation')

        else:
            # existing app service plan, do update
            self.log("App Service Plan already exists")

            if self.state == 'present':
                self.log('Result: {0}'.format(old_response))

                update_tags, newtags = self.update_tags(old_response.get('tags', dict()))

                if update_tags:
                    to_be_updated = True
                    self.tags = newtags

                # check if sku changed
                if self.sku and _normalize_sku(self.sku) != old_response['sku']['size']:
                    to_be_updated = True

                # check if number_of_workers changed
                if self.number_of_workers and int(self.number_of_workers) != old_response['sku']['capacity']:
                    to_be_updated = True

                if self.is_linux and self.is_linux != old_response['reserved']:
                    self.fail("Operation not allowed: cannot update reserved of app service plan.")

        if old_response:
            self.results['id'] = old_response['id']

        if to_be_updated:
            self.log('Need to Create/Update app service plan')
            self.results['changed'] = True

            if self.check_mode:
                return self.results

            response = self.create_or_update_plan()
            self.results['id'] = response['id']

        if self.state == 'absent' and old_response:
            self.log("Delete app service plan")
            self.results['changed'] = True

            if self.check_mode:
                return self.results

            self.delete_plan()

            self.log('App service plan instance deleted')

        return self.results

    def get_plan(self):
        '''
        Gets app service plan
        :return: deserialized app service plan dictionary
        '''
        self.log("Get App Service Plan {0}".format(self.name))

        try:
            response = self.web_client.app_service_plans.get(self.resource_group, self.name)
            self.log("Response : {0}".format(response))
            self.log("App Service Plan : {0} found".format(response.name))

            return response.as_dict()
        except CloudError as ex:
            self.log("Didn't find app service plan {0} in resource group {1}".format(self.name, self.resource_group))

        return False

    def create_or_update_plan(self):
        '''
        Creates app service plan
        :return: deserialized app service plan dictionary
        '''
        self.log("Create App Service Plan {0}".format(self.name))

        try:
            # normalize sku
            sku = _normalize_sku(self.sku)

            sku_def = SkuDescription(tier=get_sku_name(
                sku), name=sku, capacity=self.number_of_workers)
            plan_def = AppServicePlan(
                location=self.location, app_service_plan_name=self.name, sku=sku_def, reserved=self.is_linux, tags=self.tags if self.tags else None)

            poller = self.web_client.app_service_plans.create_or_update(self.resource_group, self.name, plan_def)

            if isinstance(poller, AzureOperationPoller):
                response = self.get_poller_result(poller)

            self.log("Response : {0}".format(response))

            return response.as_dict()
        except CloudError as ex:
            self.fail("Failed to create app service plan {0} in resource group {1}: {2}".format(self.name, self.resource_group, str(ex)))

    def delete_plan(self):
        '''
        Deletes specified App service plan in the specified subscription and resource group.

        :return: True
        '''
        self.log("Deleting the App service plan {0}".format(self.name))
        try:
            response = self.web_client.app_service_plans.delete(resource_group_name=self.resource_group,
                                                                name=self.name)
        except CloudError as e:
            self.log('Error attempting to delete App service plan.')
            self.fail(
                "Error deleting the App service plan : {0}".format(str(e)))

        return True


def main():
    """Main execution"""
    AzureRMAppServicePlans()


if __name__ == '__main__':
    main()
