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

# Copyright: (c) 2012, Stephen Fromm <sfromm@gmail.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': ['stableinterface'],
                    'supported_by': 'core'}

DOCUMENTATION = '''
---
module: group
author:
- Stephen Fromm (@sfromm)
version_added: "0.0.2"
short_description: Add or remove groups
requirements:
- groupadd
- groupdel
- groupmod
description:
    - Manage presence of groups on a host.
    - For Windows targets, use the M(win_group) module instead.
options:
    name:
        description:
            - Name of the group to manage.
        required: true
    gid:
        description:
            - Optional I(GID) to set for the group.
    state:
        description:
            - Whether the group should be present or not on the remote host.
        choices: [ absent, present ]
        default: present
    system:
        description:
            - If I(yes), indicates that the group created is a system group.
        type: bool
        default: 'no'
    local:
        version_added: "2.6"
        required: false
        default: 'no'
        description:
            - Forces the use of "local" command alternatives on platforms that implement it.
              This is useful in environments that use centralized authentification when you want to manipulate the local groups.
              I.E. it uses `lgroupadd` instead of `useradd`.
            - This requires that these commands exist on the targeted host, otherwise it will be a fatal error.
notes:
    - For Windows targets, use the M(win_group) module instead.
'''

EXAMPLES = '''
- name: Ensure group "somegroup" exists
  group:
    name: somegroup
    state: present
'''

import grp

from ansible.module_utils.basic import AnsibleModule, load_platform_subclass


class Group(object):
    """
    This is a generic Group manipulation class that is subclassed
    based on platform.

    A subclass may wish to override the following action methods:-
      - group_del()
      - group_add()
      - group_mod()

    All subclasses MUST define platform and distribution (which may be None).
    """

    platform = 'Generic'
    distribution = None
    GROUPFILE = '/etc/group'

    def __new__(cls, *args, **kwargs):
        return load_platform_subclass(Group, args, kwargs)

    def __init__(self, module):
        self.module = module
        self.state = module.params['state']
        self.name = module.params['name']
        self.gid = module.params['gid']
        self.system = module.params['system']
        self.local = module.params['local']

    def execute_command(self, cmd):
        return self.module.run_command(cmd)

    def group_del(self):
        if self.local:
            command_name = 'lgroupdel'
        else:
            command_name = 'groupdel'
        cmd = [self.module.get_bin_path(command_name, True), self.name]
        return self.execute_command(cmd)

    def group_add(self, **kwargs):
        if self.local:
            command_name = 'lgroupadd'
        else:
            command_name = 'groupadd'
        cmd = [self.module.get_bin_path(command_name, True)]
        for key in kwargs:
            if key == 'gid' and kwargs[key] is not None:
                cmd.append('-g')
                cmd.append(kwargs[key])
            elif key == 'system' and kwargs[key] is True:
                cmd.append('-r')
        cmd.append(self.name)
        return self.execute_command(cmd)

    def group_mod(self, **kwargs):
        if self.local:
            command_name = 'lgroupmod'
        else:
            command_name = 'groupmod'
        cmd = [self.module.get_bin_path(command_name, True)]
        info = self.group_info()
        for key in kwargs:
            if key == 'gid':
                if kwargs[key] is not None and info[2] != int(kwargs[key]):
                    cmd.append('-g')
                    cmd.append(kwargs[key])
        if len(cmd) == 1:
            return (None, '', '')
        if self.module.check_mode:
            return (0, '', '')
        cmd.append(self.name)
        return self.execute_command(cmd)

    def group_exists(self):
        try:
            if grp.getgrnam(self.name):
                return True
        except KeyError:
            return False

    def group_info(self):
        if not self.group_exists():
            return False
        try:
            info = list(grp.getgrnam(self.name))
        except KeyError:
            return False
        return info


# ===========================================

class SunOS(Group):
    """
    This is a SunOS Group manipulation class. Solaris doesn't have
    the 'system' group concept.

    This overrides the following methods from the generic class:-
        - group_add()
    """

    platform = 'SunOS'
    distribution = None
    GROUPFILE = '/etc/group'

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('groupadd', True)]
        for key in kwargs:
            if key == 'gid' and kwargs[key] is not None:
                cmd.append('-g')
                cmd.append(kwargs[key])
        cmd.append(self.name)
        return self.execute_command(cmd)


# ===========================================

class AIX(Group):
    """
    This is a AIX Group manipulation class.

    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()
    """

    platform = 'AIX'
    distribution = None
    GROUPFILE = '/etc/group'

    def group_del(self):
        cmd = [self.module.get_bin_path('rmgroup', True), self.name]
        return self.execute_command(cmd)

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('mkgroup', True)]
        for key in kwargs:
            if key == 'gid' and kwargs[key] is not None:
                cmd.append('id=' + kwargs[key])
            elif key == 'system' and kwargs[key] is True:
                cmd.append('-a')
        cmd.append(self.name)
        return self.execute_command(cmd)

    def group_mod(self, **kwargs):
        cmd = [self.module.get_bin_path('chgroup', True)]
        info = self.group_info()
        for key in kwargs:
            if key == 'gid':
                if kwargs[key] is not None and info[2] != int(kwargs[key]):
                    cmd.append('id=' + kwargs[key])
        if len(cmd) == 1:
            return (None, '', '')
        if self.module.check_mode:
            return (0, '', '')
        cmd.append(self.name)
        return self.execute_command(cmd)


# ===========================================

class FreeBsdGroup(Group):
    """
    This is a FreeBSD Group manipulation class.

    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()
    """

    platform = 'FreeBSD'
    distribution = None
    GROUPFILE = '/etc/group'

    def group_del(self):
        cmd = [self.module.get_bin_path('pw', True), 'groupdel', self.name]
        return self.execute_command(cmd)

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('pw', True), 'groupadd', self.name]
        if self.gid is not None:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        return self.execute_command(cmd)

    def group_mod(self, **kwargs):
        cmd = [self.module.get_bin_path('pw', True), 'groupmod', self.name]
        info = self.group_info()
        cmd_len = len(cmd)
        if self.gid is not None and int(self.gid) != info[2]:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        # modify the group if cmd will do anything
        if cmd_len != len(cmd):
            if self.module.check_mode:
                return (0, '', '')
            return self.execute_command(cmd)
        return (None, '', '')


class DragonFlyBsdGroup(FreeBsdGroup):
    """
    This is a DragonFlyBSD Group manipulation class.
    It inherits all behaviors from FreeBsdGroup class.
    """

    platform = 'DragonFly'


# ===========================================

class DarwinGroup(Group):
    """
    This is a Mac macOS Darwin Group manipulation class.

    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()

    group manipulation are done using dseditgroup(1).
    """

    platform = 'Darwin'
    distribution = None

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('dseditgroup', True)]
        cmd += ['-o', 'create']
        if self.gid is not None:
            cmd += ['-i', self.gid]
        elif 'system' in kwargs and kwargs['system'] is True:
            gid = self.get_lowest_available_system_gid()
            if gid is not False:
                self.gid = str(gid)
                cmd += ['-i', self.gid]
        cmd += ['-L', self.name]
        (rc, out, err) = self.execute_command(cmd)
        return (rc, out, err)

    def group_del(self):
        cmd = [self.module.get_bin_path('dseditgroup', True)]
        cmd += ['-o', 'delete']
        cmd += ['-L', self.name]
        (rc, out, err) = self.execute_command(cmd)
        return (rc, out, err)

    def group_mod(self, gid=None):
        info = self.group_info()
        if self.gid is not None and int(self.gid) != info[2]:
            cmd = [self.module.get_bin_path('dseditgroup', True)]
            cmd += ['-o', 'edit']
            if gid is not None:
                cmd += ['-i', gid]
            cmd += ['-L', self.name]
            (rc, out, err) = self.execute_command(cmd)
            return (rc, out, err)
        return (None, '', '')

    def get_lowest_available_system_gid(self):
        # check for lowest available system gid (< 500)
        try:
            cmd = [self.module.get_bin_path('dscl', True)]
            cmd += ['/Local/Default', '-list', '/Groups', 'PrimaryGroupID']
            (rc, out, err) = self.execute_command(cmd)
            lines = out.splitlines()
            highest = 0
            for group_info in lines:
                parts = group_info.split(' ')
                if len(parts) > 1:
                    gid = int(parts[-1])
                    if gid > highest and gid < 500:
                        highest = gid
            if highest == 0 or highest == 499:
                return False
            return (highest + 1)
        except:
            return False


class OpenBsdGroup(Group):
    """
    This is a OpenBSD Group manipulation class.

    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()
    """

    platform = 'OpenBSD'
    distribution = None
    GROUPFILE = '/etc/group'

    def group_del(self):
        cmd = [self.module.get_bin_path('groupdel', True), self.name]
        return self.execute_command(cmd)

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('groupadd', True)]
        if self.gid is not None:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        cmd.append(self.name)
        return self.execute_command(cmd)

    def group_mod(self, **kwargs):
        cmd = [self.module.get_bin_path('groupmod', True)]
        info = self.group_info()
        if self.gid is not None and int(self.gid) != info[2]:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        if len(cmd) == 1:
            return (None, '', '')
        if self.module.check_mode:
            return (0, '', '')
        cmd.append(self.name)
        return self.execute_command(cmd)


# ===========================================

class NetBsdGroup(Group):
    """
    This is a NetBSD Group manipulation class.

    This overrides the following methods from the generic class:-
      - group_del()
      - group_add()
      - group_mod()
    """

    platform = 'NetBSD'
    distribution = None
    GROUPFILE = '/etc/group'

    def group_del(self):
        cmd = [self.module.get_bin_path('groupdel', True), self.name]
        return self.execute_command(cmd)

    def group_add(self, **kwargs):
        cmd = [self.module.get_bin_path('groupadd', True)]
        if self.gid is not None:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        cmd.append(self.name)
        return self.execute_command(cmd)

    def group_mod(self, **kwargs):
        cmd = [self.module.get_bin_path('groupmod', True)]
        info = self.group_info()
        if self.gid is not None and int(self.gid) != info[2]:
            cmd.append('-g')
            cmd.append('%d' % int(self.gid))
        if len(cmd) == 1:
            return (None, '', '')
        if self.module.check_mode:
            return (0, '', '')
        cmd.append(self.name)
        return self.execute_command(cmd)


# ===========================================

def main():
    module = AnsibleModule(
        argument_spec=dict(
            state=dict(type='str', default='present', choices=['absent', 'present']),
            name=dict(type='str', required=True),
            gid=dict(type='str'),
            system=dict(type='bool', default=False),
            local=dict(type='bool', default=False)
        ),
        supports_check_mode=True,
    )

    group = Group(module)

    module.debug('Group instantiated - platform %s' % group.platform)
    if group.distribution:
        module.debug('Group instantiated - distribution %s' % group.distribution)

    rc = None
    out = ''
    err = ''
    result = {}
    result['name'] = group.name
    result['state'] = group.state

    if group.state == 'absent':

        if group.group_exists():
            if module.check_mode:
                module.exit_json(changed=True)
            (rc, out, err) = group.group_del()
            if rc != 0:
                module.fail_json(name=group.name, msg=err)

    elif group.state == 'present':

        if not group.group_exists():
            if module.check_mode:
                module.exit_json(changed=True)
            (rc, out, err) = group.group_add(gid=group.gid, system=group.system)
        else:
            (rc, out, err) = group.group_mod(gid=group.gid)

        if rc is not None and rc != 0:
            module.fail_json(name=group.name, msg=err)

    if rc is None:
        result['changed'] = False
    else:
        result['changed'] = True
    if out:
        result['stdout'] = out
    if err:
        result['stderr'] = err

    if group.group_exists():
        info = group.group_info()
        result['system'] = group.system
        result['gid'] = info[2]

    module.exit_json(**result)


if __name__ == '__main__':
    main()