#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright: (c) 2017, F5 Networks Inc.
# 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

DOCUMENTATION = r'''
---
module: bigip_irule
short_description: Manage iRules across different modules on a BIG-IP
description:
  - Manage iRules across different modules on a BIG-IP device.
version_added: "1.0.0"
options:
  content:
    description:
      - When used instead of B(src), sets the contents of an iRule directly to
        the specified value. This is for simple values, but can be used with
        lookup plugins for anything complex or with formatting. Either one
        of C(src) or C(content) must be provided.
    type: str
  module:
    description:
      - The BIG-IP module to which the iRule should be added.
    type: str
    required: True
    choices:
      - ltm
      - gtm
  name:
    description:
      - The name of the iRule.
    type: str
    required: True
  src:
    description:
      - The iRule file to interpret and upload to the BIG-IP. Either one
        of C(src) or C(content) must be provided.
    type: path
  state:
    description:
      - Whether the iRule should exist or not.
    type: str
    choices:
      - present
      - absent
    default: present
  partition:
    description:
      - Device partition to manage resources on.
    type: str
    default: Common
extends_documentation_fragment: f5networks.f5_modules.f5
author:
  - Tim Rupp (@caphrim007)
  - Wojciech Wypior (@wojtek0806)
'''

EXAMPLES = r'''
- name: Add the iRule contained in template irule.tcl to the LTM module
  bigip_irule:
    content: "{{ lookup('template', 'irule.tcl') }}"
    module: ltm
    name: MyiRule
    state: present
    provider:
      user: admin
      password: secret
      server: lb.mydomain.com
  delegate_to: localhost

- name: Add the iRule contained in static file irule.tcl to the LTM module
  bigip_irule:
    module: ltm
    name: MyiRule
    src: irule.tcl
    state: present
    provider:
      user: admin
      password: secret
      server: lb.mydomain.com
  delegate_to: localhost
'''

RETURN = r'''
module:
  description: The module that the iRule was added to.
  returned: changed and success
  type: str
  sample: gtm
src:
  description: The filename that included the iRule source.
  returned: changed and success, when provided
  type: str
  sample: /opt/src/irules/example1.tcl
content:
  description: The content of the iRule that was managed.
  returned: changed and success
  type: str
  sample: "when LB_FAILED { set wipHost [LB::server addr] }"
'''

import os
from datetime import datetime

from ansible.module_utils.basic import (
    AnsibleModule, env_fallback
)

from ..module_utils.bigip import F5RestClient
from ..module_utils.common import (
    F5ModuleError, AnsibleF5Parameters, transform_name, f5_argument_spec
)
from ..module_utils.icontrol import tmos_version
from ..module_utils.teem import send_teem


class Parameters(AnsibleF5Parameters):
    api_map = {
        'apiAnonymous': 'content',
    }

    updatables = [
        'content',
    ]

    api_attributes = [
        'apiAnonymous',
    ]

    returnables = [
        'content', 'src', 'module',
    ]


class ApiParameters(Parameters):
    pass


class ModuleParameters(Parameters):
    @property
    def content(self):
        if self._values['content'] is None:
            result = self.src_content
        else:
            result = self._values['content']

        return str(result).strip()

    @property
    def src(self):
        if self._values['src'] is None:
            return None
        return self._values['src']

    @property
    def src_content(self):
        if not os.path.exists(self._values['src']):
            raise F5ModuleError(
                "The specified 'src' was not found."
            )
        with open(self._values['src']) as f:
            result = f.read()
        return result


class Changes(Parameters):
    def to_return(self):
        result = {}
        try:
            for returnable in self.returnables:
                result[returnable] = getattr(self, returnable)
            result = self._filter_params(result)
        except Exception:
            raise
        return result


class UsableChanges(Changes):
    pass


class ReportableChanges(Changes):
    pass


class Difference(object):
    def __init__(self, want, have=None):
        self.want = want
        self.have = have

    def compare(self, param):
        try:
            result = getattr(self, param)
            return result
        except AttributeError:
            return self.__default(param)

    def __default(self, param):
        attr1 = getattr(self.want, param)
        try:
            attr2 = getattr(self.have, param)
            if attr1 != attr2:
                return attr1
        except AttributeError:
            return attr1


class ModuleManager(object):
    def __init__(self, *args, **kwargs):
        self.client = kwargs.get('client', None)
        self.module = kwargs.get('module', None)
        self.kwargs = kwargs

    def exec_module(self):
        if self.module.params['module'] == 'ltm':
            manager = self.get_manager('ltm')
        elif self.module.params['module'] == 'gtm':
            manager = self.get_manager('gtm')
        else:
            raise F5ModuleError(
                "An unknown iRule module type was specified"
            )
        return manager.exec_module()

    def get_manager(self, type):
        if type == 'ltm':
            return LtmManager(**self.kwargs)
        elif type == 'gtm':
            return GtmManager(**self.kwargs)


class BaseManager(object):
    def __init__(self, *args, **kwargs):
        self.module = kwargs.get('module', None)
        self.client = F5RestClient(**self.module.params)
        self.have = None
        self.want = ModuleParameters(params=self.module.params)
        self.changes = UsableChanges()

    def _set_changed_options(self):
        changed = {}
        for key in Parameters.returnables:
            if getattr(self.want, key) is not None:
                changed[key] = getattr(self.want, key)
        if changed:
            self.changes = UsableChanges(params=changed)

    def _update_changed_options(self):
        diff = Difference(self.want, self.have)
        updatables = Parameters.updatables
        changed = dict()
        for k in updatables:
            change = diff.compare(k)
            if change is None:
                continue
            else:
                if isinstance(change, dict):
                    changed.update(change)
                else:
                    changed[k] = change
        if changed:
            self.changes = UsableChanges(params=changed)
            return True
        return False

    def _announce_deprecations(self, result):
        warnings = result.pop('__warnings', [])
        for warning in warnings:
            self.module.deprecate(
                msg=warning['msg'],
                version=warning['version']
            )

    def exec_module(self):
        start = datetime.now().isoformat()
        version = tmos_version(self.client)
        changed = False
        result = dict()
        state = self.want.state

        if state in ["present"]:
            changed = self.present()
        elif state == "absent":
            changed = self.absent()

        reportable = ReportableChanges(params=self.changes.to_return())
        changes = reportable.to_return()
        result.update(**changes)
        result.update(dict(changed=changed))
        self._announce_deprecations(result)
        send_teem(start, self.client, self.module, version)
        return result

    def present(self):
        if not self.want.content and not self.want.src:
            raise F5ModuleError(
                "Either 'content' or 'src' must be provided"
            )
        if self.exists():
            return self.update()
        else:
            return self.create()

    def create(self):
        self._set_changed_options()
        if self.module.check_mode:
            return True
        self.create_on_device()
        if not self.exists():
            raise F5ModuleError("Failed to create the iRule")
        return True

    def should_update(self):
        result = self._update_changed_options()
        if result:
            return True
        return False

    def update(self):
        self.have = self.read_current_from_device()
        if not self.should_update():
            return False
        if self.module.check_mode:
            return True
        self.update_on_device()
        return True

    def absent(self):
        if self.exists():
            return self.remove()
        return False

    def remove(self):
        if self.module.check_mode:
            return True
        self.remove_from_device()
        if self.exists():
            raise F5ModuleError("Failed to delete the iRule")
        return True


class LtmManager(BaseManager):
    def exists(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.get(uri)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status == 404 or 'code' in response and response['code'] == 404:
            return False
        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True

        errors = [401, 403, 409, 500, 501, 502, 503, 504]

        if resp.status in errors or 'code' in response and response['code'] in errors:
            if 'message' in response:
                raise F5ModuleError(response['message'])
            else:
                raise F5ModuleError(resp.content)

    def update_on_device(self):
        params = self.changes.api_params()
        uri = "https://{0}:{1}/mgmt/tm/ltm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.patch(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True
        raise F5ModuleError(resp.content)

    def create_on_device(self):
        params = self.changes.api_params()
        params['name'] = self.want.name
        params['partition'] = self.want.partition
        uri = "https://{0}:{1}/mgmt/tm/ltm/rule/".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
        )
        resp = self.client.api.post(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True
        raise F5ModuleError(resp.content)

    def read_current_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )

        resp = self.client.api.get(uri)

        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return ApiParameters(params=response)
        raise F5ModuleError(resp.content)

    def remove_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/ltm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        response = self.client.api.delete(uri)

        if response.status in [200, 201]:
            return True
        raise F5ModuleError(response.content)


class GtmManager(BaseManager):
    def exists(self):
        uri = "https://{0}:{1}/mgmt/tm/gtm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.get(uri)
        try:
            response = resp.json()
        except ValueError:
            return False
        if resp.status == 404 or 'code' in response and response['code'] == 404:
            return False
        return True

    def update_on_device(self):
        params = self.changes.api_params()
        uri = "https://{0}:{1}/mgmt/tm/gtm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        resp = self.client.api.patch(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True
        raise F5ModuleError(resp.content)

    def create_on_device(self):
        params = self.changes.api_params()
        params['name'] = self.want.name
        params['partition'] = self.want.partition
        uri = "https://{0}:{1}/mgmt/tm/gtm/rule/".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
        )
        resp = self.client.api.post(uri, json=params)
        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return True
        raise F5ModuleError(resp.content)

    def read_current_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/gtm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )

        resp = self.client.api.get(uri)

        try:
            response = resp.json()
        except ValueError as ex:
            raise F5ModuleError(str(ex))

        if resp.status in [200, 201] or 'code' in response and response['code'] in [200, 201]:
            return ApiParameters(params=response)
        raise F5ModuleError(resp.content)

    def remove_from_device(self):
        uri = "https://{0}:{1}/mgmt/tm/gtm/rule/{2}".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
            transform_name(self.want.partition, self.want.name)
        )
        response = self.client.api.delete(uri)

        if response.status in [200, 201]:
            return True
        raise F5ModuleError(response.content)


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        argument_spec = dict(
            content=dict(),
            src=dict(
                type='path',
            ),
            name=dict(required=True),
            module=dict(
                required=True,
                choices=['gtm', 'ltm']
            ),
            state=dict(
                default='present',
                choices=['present', 'absent']
            ),
            partition=dict(
                default='Common',
                fallback=(env_fallback, ['F5_PARTITION'])
            )
        )
        self.argument_spec = {}
        self.argument_spec.update(f5_argument_spec)
        self.argument_spec.update(argument_spec)
        self.mutually_exclusive = [
            ['content', 'src']
        ]


def main():
    spec = ArgumentSpec()

    module = AnsibleModule(
        argument_spec=spec.argument_spec,
        supports_check_mode=spec.supports_check_mode,
        mutually_exclusive=spec.mutually_exclusive
    )

    try:
        mm = ModuleManager(module=module)
        results = mm.exec_module()
        module.exit_json(**results)
    except F5ModuleError as ex:
        module.fail_json(msg=str(ex))


if __name__ == '__main__':
    main()
