#!/usr/bin/python
# -*- coding: utf-8 -*-

# Copyright: (c) 2017, IBM Corp
# Author(s): Andreas Nafpliotis <nafpliot@de.ibm.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: vmware_cfg_backup
short_description: Backup / Restore / Reset ESXi host configuration
description:
    - This module can be used to perform various operations related to backup, restore and reset of ESXi host configuration.
version_added: "2.5"
author:
    - Andreas Nafpliotis (@nafpliot-ibm)
notes:
    - Tested on ESXi 6.0
    - Works only for ESXi hosts
    - For configuration save or reset, the host will be switched automatically to maintenance mode.
requirements:
    - "python >= 2.6"
    - PyVmomi installed
options:
    esxi_hostname:
        description:
            - Name of ESXi server. This is required only if authentication against a vCenter is done.
        required: False
    dest:
        description:
            - The destination where the ESXi configuration bundle will be saved. The I(dest) can be a folder or a file.
            - If I(dest) is a folder, the backup file will be saved in the folder with the default filename generated from the ESXi server.
            - If I(dest) is a file, the backup file will be saved with that filename. The file extension will always be .tgz.
    src:
        description:
            - The file containing the ESXi configuration that will be restored.
    state:
        description:
            - If C(saved), the .tgz backup bundle will be saved in I(dest).
            - If C(absent), the host configuration will be reset to default values.
            - If C(loaded), the backup file in I(src) will be loaded to the ESXi host rewriting the hosts settings.
        choices: [saved, absent, loaded]
extends_documentation_fragment: vmware.documentation
'''

EXAMPLES = '''
- name: Save the ESXi configuration locally by authenticating directly against the ESXi host
  vmware_cfg_backup:
    hostname: '{{ esxi_hostname }}'
    username: '{{ esxi_username }}'
    password: '{{ esxi_password }}'
    state: saved
    dest: /tmp/
  delegate_to: localhost

- name: Save the ESXi configuration locally by authenticating against the vCenter and selecting the ESXi host
  vmware_cfg_backup:
    hostname: '{{ vcenter_hostname }}'
    esxi_hostname: '{{ esxi_hostname }}'
    username: '{{ esxi_username }}'
    password: '{{ esxi_password }}'
    state: saved
    dest: /tmp/
  delegate_to: localhost
'''

RETURN = '''
dest_file:
    description: The full path of where the file holding the ESXi configurations was stored
    returned: changed
    type: string
    sample: /tmp/configBundle-esxi.host.domain.tgz
'''

import os
try:
    from pyVmomi import vim
except ImportError:
    pass

from ansible.module_utils.vmware import vmware_argument_spec, get_all_objs, wait_for_task, PyVmomi
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.urls import open_url
from ansible.module_utils.six.moves.urllib.error import HTTPError
from ansible.module_utils._text import to_native


class VMwareConfigurationBackup(PyVmomi):
    def __init__(self, module):
        super(VMwareConfigurationBackup, self).__init__(module)
        self.state = self.module.params['state']
        self.dest = self.module.params['dest']
        self.src = self.module.params['src']
        self.hostname = self.module.params['hostname']
        self.username = self.module.params['username']
        self.password = self.module.params['password']
        self.validate_certs = self.module.params['validate_certs']
        self.esxi_hostname = self.module.params.get('esxi_hostname', None)
        self.host = self.find_host_system()

    def find_host_system(self):
        if self.esxi_hostname:
            host_system_obj = self.find_hostsystem_by_name(host_name=self.esxi_hostname)
            if host_system_obj:
                return host_system_obj
            else:
                self.module.fail_json(msg="Failed to find ESXi %s" % self.esxi_hostname)

        host_system = get_all_objs(self.content, [vim.HostSystem])
        return host_system.keys()[0]

    def process_state(self):
        if self.state == 'saved':
            self.save_configuration()

        if self.state == 'absent':
            self.reset_configuration()

        if self.state == 'loaded':
            self.load_configuration()

    def load_configuration(self):
        if not os.path.isfile(self.src):
            self.module.fail_json(msg="Source file {} does not exist".format(self.src))

        url = self.host.configManager.firmwareSystem.QueryFirmwareConfigUploadURL()
        url = url.replace('*', self.host.name)
        # find manually the url if there is a redirect because urllib2 -per RFC- doesn't do automatic redirects for PUT requests
        try:
            request = open_url(url=url, method='HEAD', validate_certs=self.validate_certs)
        except HTTPError as e:
            url = e.geturl()

        try:
            with open(self.src, 'rb') as file:
                data = file.read()
            request = open_url(url=url, data=data, method='PUT', validate_certs=self.validate_certs,
                               url_username=self.username, url_password=self.password, force_basic_auth=True)
        except Exception as e:
            self.module.fail_json(msg=to_native(e))

        if not self.host.runtime.inMaintenanceMode:
            self.enter_maintenance()
        try:
            self.host.configManager.firmwareSystem.RestoreFirmwareConfiguration(force=True)
            self.module.exit_json(changed=True)
        except Exception as e:
            self.exit_maintenance()
            self.module.fail_json(msg=to_native(e))

    def reset_configuration(self):
        if not self.host.runtime.inMaintenanceMode:
            self.enter_maintenance()
        try:
            self.host.configManager.firmwareSystem.ResetFirmwareToFactoryDefaults()
            self.module.exit_json(changed=True)
        except Exception as e:
            self.exit_maintenance()
            self.module.fail_json(msg=to_native(e))

    def save_configuration(self):
        url = self.host.configManager.firmwareSystem.BackupFirmwareConfiguration()
        url = url.replace('*', self.host.name)
        if os.path.isdir(self.dest):
            filename = url.rsplit('/', 1)[1]
            self.dest = os.path.join(self.dest, filename)
        else:
            filename, file_extension = os.path.splitext(self.dest)
            if file_extension != ".tgz":
                self.dest = filename + ".tgz"
        try:
            request = open_url(url=url, validate_certs=self.validate_certs)
            with open(self.dest, "wb") as file:
                file.write(request.read())
            self.module.exit_json(changed=True, dest_file=self.dest)
        except IOError as e:
            self.module.fail_json(msg="Failed to write backup file. Ensure that "
                                      "the dest path exists and is writable. Details : %s" % to_native(e))
        except Exception as e:
            self.module.fail_json(msg=to_native(e))

    def enter_maintenance(self):
        try:
            task = self.host.EnterMaintenanceMode_Task(timeout=15)
            success, result = wait_for_task(task)
        except Exception as e:
            self.module.fail_json(msg="Failed to enter maintenance mode."
                                      " Ensure that there are no powered on machines on the host. %s" % to_native(e))

    def exit_maintenance(self):
        try:
            task = self.host.ExitMaintenanceMode_Task(timeout=15)
            success, result = wait_for_task(task)
        except Exception as generic_exc:
            self.module.fail_json(msg="Failed to exit maintenance mode due to %s" % to_native(generic_exc))


def main():
    argument_spec = vmware_argument_spec()
    argument_spec.update(dict(dest=dict(required=False, type='path'),
                              esxi_hostname=dict(required=False, type='str'),
                              src=dict(required=False, type='path'),
                              state=dict(required=True, choices=['saved', 'absent', 'loaded'], type='str')))
    required_if = [('state', 'saved', ['dest']),
                   ('state', 'loaded', ['src'])]

    module = AnsibleModule(argument_spec=argument_spec,
                           required_if=required_if,
                           supports_check_mode=False)

    vmware_cfg_backup = VMwareConfigurationBackup(module)
    vmware_cfg_backup.process_state()


if __name__ == '__main__':
    main()
