#!/usr/bin/python
# Copyright 2013 Google Inc.
#
# 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: gce
version_added: "1.4"
short_description: create or terminate GCE instances
description:
     - Creates or terminates Google Compute Engine (GCE) instances.  See
       U(https://cloud.google.com/products/compute-engine) for an overview.
       Full install/configuration instructions for the gce* modules can
       be found in the comments of ansible/test/gce_tests.py.
options:
  image:
    description:
       - image string to use for the instance
    required: false
    default: "debian-7"
  instance_names:
    description:
      - a comma-separated list of instance names to create or destroy
    required: false
    default: null
  machine_type:
    description:
      - machine type to use for the instance, use 'n1-standard-1' by default
    required: false
    default: "n1-standard-1"
  metadata:
    description:
      - a hash/dictionary of custom data for the instance;
        '{"key":"value", ...}'
    required: false
    default: null
  service_account_email:
    version_added: "1.5.1"
    description:
      - service account email
    required: false
    default: null
  service_account_permissions:
    version_added: "2.0"
    description:
      - service account permissions (see
        U(https://cloud.google.com/sdk/gcloud/reference/compute/instances/create),
        --scopes section for detailed information)
    required: false
    default: null
    choices: [
      "bigquery", "cloud-platform", "compute-ro", "compute-rw",
      "useraccounts-ro", "useraccounts-rw", "datastore", "logging-write",
      "monitoring", "sql", "sql-admin", "storage-full", "storage-ro",
      "storage-rw", "taskqueue", "userinfo-email"
    ]
  pem_file:
    version_added: "1.5.1"
    description:
      - path to the pem file associated with the service account email
        This option is deprecated. Use 'credentials_file'.
    required: false
    default: null
  credentials_file:
    version_added: "2.1.0"
    description:
      - path to the JSON file associated with the service account email
    default: null
    required: false
  project_id:
    version_added: "1.5.1"
    description:
      - your GCE project ID
    required: false
    default: null
  name:
    description:
      - identifier when working with a single instance
    required: false
  network:
    description:
      - name of the network, 'default' will be used if not specified
    required: false
    default: "default"
  subnetwork:
    description:
      - name of the subnetwork in which the instance should be created
    required: false
    default: null
    version_added: "2.2"
  persistent_boot_disk:
    description:
      - if set, create the instance with a persistent boot disk
    required: false
    default: "false"
  disks:
    description:
      - a list of persistent disks to attach to the instance; a string value
        gives the name of the disk; alternatively, a dictionary value can
        define 'name' and 'mode' ('READ_ONLY' or 'READ_WRITE'). The first entry
        will be the boot disk (which must be READ_WRITE).
    required: false
    default: null
    version_added: "1.7"
  state:
    description:
      - desired state of the resource
    required: false
    default: "present"
    choices: ["active", "present", "absent", "deleted", "started", "stopped", "terminated"]
  tags:
    description:
      - a comma-separated list of tags to associate with the instance
    required: false
    default: null
  zone:
    description:
      - the GCE zone to use
    required: true
    default: "us-central1-a"
  ip_forward:
    version_added: "1.9"
    description:
      - set to true if the instance can forward ip packets (useful for
        gateways)
    required: false
    default: "false"
  external_ip:
    version_added: "1.9"
    description:
      - type of external ip, ephemeral by default; alternatively, a list of fixed gce ips or ip names can be given (if there is not enough specified ip, 'ephemeral' will be used). Specify 'none' if no external ip is desired.
    required: false
    default: "ephemeral"
  disk_auto_delete:
    version_added: "1.9"
    description:
      - if set boot disk will be removed after instance destruction
    required: false
    default: "true"
  preemptible:
    version_added: "2.1"
    description:
      - if set to true, instances will be preemptible and time-limited.
        (requires libcloud >= 0.20.0)
    required: false
    default: "false"

requirements:
    - "python >= 2.6"
    - "apache-libcloud >= 0.13.3, >= 0.17.0 if using JSON credentials,
      >= 0.20.0 if using preemptible option"
notes:
  - Either I(name) or I(instance_names) is required.
author: "Eric Johnson (@erjohnso) <erjohnso@google.com>"
'''

EXAMPLES = '''
# Basic provisioning example.  Create a single Debian 7 instance in the
# us-central1-a Zone of n1-standard-1 machine type.
- local_action:
    module: gce
    name: test-instance
    zone: us-central1-a
    machine_type: n1-standard-1
    image: debian-7

# Example using defaults and with metadata to create a single 'foo' instance
- local_action:
    module: gce
    name: foo
    metadata: '{"db":"postgres", "group":"qa", "id":500}'


# Launch instances from a control node, runs some tasks on the new instances,
# and then terminate them
# This example uses JSON credentials with the credentials_file parameter
# rather than the deprecated pem_file option with PEM formatted credentials.

- name: Create a sandbox instance
  hosts: localhost
  vars:
    names: foo,bar
    machine_type: n1-standard-1
    image: debian-6
    zone: us-central1-a
    service_account_email: unique-email@developer.gserviceaccount.com
    credentials_file: /path/to/json_file
    project_id: project-id
  tasks:
    - name: Launch instances
      local_action: gce instance_names={{names}} machine_type={{machine_type}}
                    image={{image}} zone={{zone}}
                    service_account_email={{ service_account_email }}
                    credentials_file={{ credentials_file }}
                    project_id={{ project_id }}
      register: gce
    - name: Wait for SSH to come up
      local_action: wait_for host={{item.public_ip}} port=22 delay=10
                    timeout=60 state=started
      with_items: {{gce.instance_data}}

- name: Configure instance(s)
  hosts: launched
  become: True
  roles:
    - my_awesome_role
    - my_awesome_tasks

- name: Terminate instances
  hosts: localhost
  connection: local
  tasks:
    - name: Terminate instances that were previously launched
      local_action:
        module: gce
        state: 'absent'
        instance_names: {{gce.instance_names}}

# The deprecated PEM file credentials can be used as follows
- name: Create a sandbox instance with PEM credentials
  hosts: localhost
  vars:
    names: foo,bar
    machine_type: n1-standard-1
    image: debian-6
    zone: us-central1-a
    service_account_email: unique-email@developer.gserviceaccount.com
    pem_file: /path/to/pem_file
    project_id: project-id
  tasks:
    - name: Launch instances
      local_action: gce instance_names={{names}} machine_type={{machine_type}}
                    image={{image}} zone={{zone}}
                    service_account_email={{ service_account_email }}
                    pem_file={{ pem_file }}
                    project_id={{ project_id }}
      register: gce
    - name: Wait for SSH to come up
      local_action: wait_for host={{item.public_ip}} port=22 delay=10
                    timeout=60 state=started
      with_items: {{gce.instance_data}}

'''

import socket

try:
    import libcloud
    from libcloud.compute.types import Provider
    from libcloud.compute.providers import get_driver
    from libcloud.common.google import GoogleBaseError, QuotaExceededError, \
        ResourceExistsError, ResourceInUseError, ResourceNotFoundError
    from libcloud.compute.drivers.gce import GCEAddress
    _ = Provider.GCE
    HAS_LIBCLOUD = True
except ImportError:
    HAS_LIBCLOUD = False

try:
    from ast import literal_eval
    HAS_PYTHON26 = True
except ImportError:
    HAS_PYTHON26 = False


def get_instance_info(inst):
    """Retrieves instance information from an instance object and returns it
    as a dictionary.

    """
    metadata = {}
    if 'metadata' in inst.extra and 'items' in inst.extra['metadata']:
        for md in inst.extra['metadata']['items']:
            metadata[md['key']] = md['value']

    try:
        netname = inst.extra['networkInterfaces'][0]['network'].split('/')[-1]
    except:
        netname = None
    try:
        subnetname = inst.extra['networkInterfaces'][0]['subnetwork'].split('/')[-1]
    except:
        subnetname = None
    if 'disks' in inst.extra:
        disk_names = [disk_info['source'].split('/')[-1]
                      for disk_info
                      in sorted(inst.extra['disks'],
                                key=lambda disk_info: disk_info['index'])]
    else:
        disk_names = []

    if len(inst.public_ips) == 0:
        public_ip = None
    else:
        public_ip = inst.public_ips[0]

    return({
        'image': inst.image is not None and inst.image.split('/')[-1] or None,
        'disks': disk_names,
        'machine_type': inst.size,
        'metadata': metadata,
        'name': inst.name,
        'network': netname,
        'subnetwork': subnetname,
        'private_ip': inst.private_ips[0],
        'public_ip': public_ip,
        'status': ('status' in inst.extra) and inst.extra['status'] or None,
        'tags': ('tags' in inst.extra) and inst.extra['tags'] or [],
        'zone': ('zone' in inst.extra) and inst.extra['zone'].name or None,
    })


def create_instances(module, gce, instance_names):
    """Creates new instances. Attributes other than instance_names are picked
    up from 'module'

    module : AnsibleModule object
    gce: authenticated GCE libcloud driver
    instance_names: python list of instance names to create

    Returns:
        A list of dictionaries with instance information
        about the instances that were launched.

    """
    image = module.params.get('image')
    machine_type = module.params.get('machine_type')
    metadata = module.params.get('metadata')
    network = module.params.get('network')
    subnetwork = module.params.get('subnetwork')
    persistent_boot_disk = module.params.get('persistent_boot_disk')
    disks = module.params.get('disks')
    state = module.params.get('state')
    tags = module.params.get('tags')
    zone = module.params.get('zone')
    ip_forward = module.params.get('ip_forward')
    external_ip = module.params.get('external_ip')
    disk_auto_delete = module.params.get('disk_auto_delete')
    preemptible = module.params.get('preemptible')
    service_account_permissions = module.params.get('service_account_permissions')
    service_account_email = module.params.get('service_account_email')

    if external_ip == "none":
        instance_external_ip = None
    elif not isinstance(external_ip, basestring):
        try:
            if len(external_ip) != 0:
                instance_external_ip = external_ip.pop(0)
                # check if instance_external_ip is an ip or a name
                try:
                    socket.inet_aton(instance_external_ip)
                    instance_external_ip = GCEAddress(id='unknown', name='unknown', address=instance_external_ip, region='unknown', driver=gce)
                except socket.error:
                    instance_external_ip = gce.ex_get_address(instance_external_ip)
            else:
                instance_external_ip = 'ephemeral'
        except GoogleBaseError as e:
            module.fail_json(msg='Unexpected error attempting to get a static ip %s, error: %s' % (external_ip, e.value))
    else:
        instance_external_ip = external_ip

    new_instances = []
    changed = False

    lc_disks = []
    disk_modes = []
    for i, disk in enumerate(disks or []):
        if isinstance(disk, dict):
            lc_disks.append(gce.ex_get_volume(disk['name']))
            disk_modes.append(disk['mode'])
        else:
            lc_disks.append(gce.ex_get_volume(disk))
            # boot disk is implicitly READ_WRITE
            disk_modes.append('READ_ONLY' if i > 0 else 'READ_WRITE')
    lc_network = gce.ex_get_network(network)
    lc_machine_type = gce.ex_get_size(machine_type)
    lc_zone = gce.ex_get_zone(zone)

    # Try to convert the user's metadata value into the format expected
    # by GCE.  First try to ensure user has proper quoting of a
    # dictionary-like syntax using 'literal_eval', then convert the python
    # dict into a python list of 'key' / 'value' dicts.  Should end up
    # with:
    # [ {'key': key1, 'value': value1}, {'key': key2, 'value': value2}, ...]
    if metadata:
        if isinstance(metadata, dict):
            md = metadata
        else:
            try:
                md = literal_eval(str(metadata))
                if not isinstance(md, dict):
                    raise ValueError('metadata must be a dict')
            except ValueError as e:
                module.fail_json(msg='bad metadata: %s' % str(e))
            except SyntaxError as e:
                module.fail_json(msg='bad metadata syntax')

        if hasattr(libcloud, '__version__') and libcloud.__version__ < '0.15':
            items = []
            for k, v in md.items():
                items.append({"key": k, "value": v})
            metadata = {'items': items}
        else:
            metadata = md

    lc_image = LazyDiskImage(module, gce, image, lc_disks)
    ex_sa_perms = []
    bad_perms = []
    if service_account_permissions:
        for perm in service_account_permissions:
            if perm not in gce.SA_SCOPES_MAP.keys():
                bad_perms.append(perm)
        if len(bad_perms) > 0:
            module.fail_json(msg='bad permissions: %s' % str(bad_perms))
        ex_sa_perms.append({'email': "default"})
        ex_sa_perms[0]['scopes'] = service_account_permissions

    # These variables all have default values but check just in case
    if not lc_network or not lc_machine_type or not lc_zone:
        module.fail_json(msg='Missing required create instance variable',
                         changed=False)

    for name in instance_names:
        pd = None
        if lc_disks:
            pd = lc_disks[0]
        elif persistent_boot_disk:
            try:
                pd = gce.ex_get_volume("%s" % name, lc_zone)
            except ResourceNotFoundError:
                pd = gce.create_volume(None, "%s" % name, image=lc_image())

        gce_args = dict(
            location=lc_zone,
            ex_network=network, ex_tags=tags, ex_metadata=metadata,
            ex_boot_disk=pd, ex_can_ip_forward=ip_forward,
            external_ip=instance_external_ip, ex_disk_auto_delete=disk_auto_delete,
            ex_service_accounts=ex_sa_perms
        )
        if preemptible is not None:
            gce_args['ex_preemptible'] = preemptible
        if subnetwork is not None:
            gce_args['ex_subnetwork'] = subnetwork

        inst = None
        try:
            inst = gce.ex_get_node(name, lc_zone)
        except ResourceNotFoundError:
            inst = gce.create_node(
                name, lc_machine_type, lc_image(), **gce_args
            )
            changed = True
        except GoogleBaseError as e:
            module.fail_json(msg='Unexpected error attempting to create ' +
                             'instance %s, error: %s' % (name, e.value))

        for i, lc_disk in enumerate(lc_disks):
            # Check whether the disk is already attached
            if (len(inst.extra['disks']) > i):
                attached_disk = inst.extra['disks'][i]
                if attached_disk['source'] != lc_disk.extra['selfLink']:
                    module.fail_json(
                        msg=("Disk at index %d does not match: requested=%s found=%s" % (
                            i, lc_disk.extra['selfLink'], attached_disk['source'])))
                elif attached_disk['mode'] != disk_modes[i]:
                    module.fail_json(
                        msg=("Disk at index %d is in the wrong mode: requested=%s found=%s" % (
                            i, disk_modes[i], attached_disk['mode'])))
                else:
                    continue
            gce.attach_volume(inst, lc_disk, ex_mode=disk_modes[i])
            # Work around libcloud bug: attached volumes don't get added
            # to the instance metadata. get_instance_info() only cares about
            # source and index.
            if len(inst.extra['disks']) != i+1:
                inst.extra['disks'].append(
                    {'source': lc_disk.extra['selfLink'], 'index': i})

        if inst:
            new_instances.append(inst)

    instance_names = []
    instance_json_data = []
    for inst in new_instances:
        d = get_instance_info(inst)
        instance_names.append(d['name'])
        instance_json_data.append(d)

    return (changed, instance_json_data, instance_names)

def change_instance_state(module, gce, instance_names, zone_name, state):
    """Changes the state of a list of instances. For example,
    change from started to stopped, or started to absent.

    module: Ansible module object
    gce: authenticated GCE connection object
    instance_names: a list of instance names to terminate
    zone_name: the zone where the instances reside prior to termination
    state: 'state' parameter passed into module as argument

    Returns a dictionary of instance names that were changed.

    """
    changed = False
    changed_instance_names = []
    for name in instance_names:
        inst = None
        try:
            inst = gce.ex_get_node(name, zone_name)
        except ResourceNotFoundError:
            pass
        except Exception as e:
            module.fail_json(msg=unexpected_error_msg(e), changed=False)
        if inst and state in ['absent', 'deleted']:
            gce.destroy_node(inst)
            changed_instance_names.append(inst.name)
            changed = True
        elif inst and state == 'started' and \
                  inst.state == libcloud.compute.types.NodeState.STOPPED:
            gce.ex_start_node(inst)
            changed_instance_names.append(inst.name)
            changed = True
        elif inst and state in ['stopped', 'terminated'] and \
                  inst.state == libcloud.compute.types.NodeState.RUNNING:
            gce.ex_stop_node(inst)
            changed_instance_names.append(inst.name)
            changed = True

    return (changed, changed_instance_names)

def main():
    module = AnsibleModule(
        argument_spec = dict(
            image = dict(default='debian-7'),
            instance_names = dict(),
            machine_type = dict(default='n1-standard-1'),
            metadata = dict(),
            name = dict(),
            network = dict(default='default'),
            subnetwork = dict(),
            persistent_boot_disk = dict(type='bool', default=False),
            disks = dict(type='list'),
            state = dict(choices=['active', 'present', 'absent', 'deleted',
                                  'started', 'stopped', 'terminated'],
                         default='present'),
            tags = dict(type='list'),
            zone = dict(default='us-central1-a'),
            service_account_email = dict(),
            service_account_permissions = dict(type='list'),
            pem_file = dict(),
            credentials_file = dict(),
            project_id = dict(),
            ip_forward = dict(type='bool', default=False),
            external_ip=dict(default='ephemeral'),
            disk_auto_delete = dict(type='bool', default=True),
            preemptible = dict(type='bool', default=None),
        )
    )

    if not HAS_PYTHON26:
        module.fail_json(msg="GCE module requires python's 'ast' module, python v2.6+")
    if not HAS_LIBCLOUD:
        module.fail_json(msg='libcloud with GCE support (0.17.0+) required for this module')

    gce = gce_connect(module)

    image = module.params.get('image')
    instance_names = module.params.get('instance_names')
    machine_type = module.params.get('machine_type')
    metadata = module.params.get('metadata')
    name = module.params.get('name')
    network = module.params.get('network')
    subnetwork = module.params.get('subnetwork')
    persistent_boot_disk = module.params.get('persistent_boot_disk')
    state = module.params.get('state')
    tags = module.params.get('tags')
    zone = module.params.get('zone')
    ip_forward = module.params.get('ip_forward')
    preemptible = module.params.get('preemptible')
    changed = False

    inames = []
    if isinstance(instance_names, list):
        inames = instance_names
    elif isinstance(instance_names, str):
        inames = instance_names.split(',')
    if name:
        inames.append(name)
    if not inames:
        module.fail_json(msg='Must specify a "name" or "instance_names"',
                         changed=False)
    if not zone:
        module.fail_json(msg='Must specify a "zone"', changed=False)

    if preemptible is not None and hasattr(libcloud, '__version__') and libcloud.__version__ < '0.20':
        module.fail_json(msg="Apache Libcloud 0.20.0+ is required to use 'preemptible' option",
                         changed=False)

    if subnetwork is not None and not hasattr(gce, 'ex_get_subnetwork'):
        module.fail_json(msg="Apache Libcloud 1.0.0+ is required to use 'subnetwork' option",
                         changed=False)

    json_output = {'zone': zone}
    if state in ['absent', 'deleted', 'started', 'stopped', 'terminated']:
        json_output['state'] = state
        (changed, changed_instance_names) = change_instance_state(
            module, gce, inames, zone, state)

        # based on what user specified, return the same variable, although
        # value could be different if an instance could not be destroyed
        if instance_names:
            json_output['instance_names'] = changed_instance_names
        elif name:
            json_output['name'] = name

    elif state in ['active', 'present']:
        json_output['state'] = 'present'
        (changed, instance_data, instance_name_list) = create_instances(
            module, gce, inames)
        json_output['instance_data'] = instance_data
        if instance_names:
            json_output['instance_names'] = instance_name_list
        elif name:
            json_output['name'] = name

    json_output['changed'] = changed
    module.exit_json(**json_output)


class LazyDiskImage:
    """
    Object for lazy instantiation of disk image
    gce.ex_get_image is a very expensive call, so we want to avoid calling it as much as possible.
    """
    def __init__(self, module, gce, name, has_pd):
        self.image = None
        self.was_called = False
        self.gce = gce
        self.name = name
        self.has_pd = has_pd
        self.module = module

    def __call__(self):
        if not self.was_called:
            self.was_called = True
            if not self.has_pd:
                self.image = self.gce.ex_get_image(self.name)
                if not self.image:
                    self.module.fail_json(msg='image or disks missing for create instance', changed=False)
        return self.image


# import module snippets
from ansible.module_utils.basic import *
from ansible.module_utils.gce import *
if __name__ == '__main__':
    main()
