#!/usr/bin/python

# Copyright: (c) 2017, Ansible Project
# 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 = '''
---
module: xattr
short_description: Manage user defined extended attributes
description:
    - Manages filesystem user defined extended attributes.
    - Requires that extended attributes are enabled on the target filesystem
      and that the setfattr/getfattr utilities are present.
options:
  path:
    description:
      - The full path of the file/object to get the facts of.
      - Before 2.3 this option was only usable as I(name).
    type: path
    required: true
    aliases: [ name ]
  namespace:
    description:
      - Namespace of the named name/key.
    type: str
    default: user
  key:
    description:
      - The name of a specific Extended attribute key to set/retrieve.
    type: str
  value:
    description:
      - The value to set the named name/key to, it automatically sets the C(state) to 'set'.
    type: str
  state:
    description:
      - defines which state you want to do.
        C(read) retrieves the current value for a C(key) (default)
        C(present) sets C(name) to C(value), default if value is set
        C(all) dumps all data
        C(keys) retrieves all keys
        C(absent) deletes the key
    type: str
    choices: [ absent, all, keys, present, read ]
    default: read
  follow:
    description:
      - If C(yes), dereferences symlinks and sets/gets attributes on symlink target,
        otherwise acts on symlink itself.
    type: bool
    default: yes
notes:
  - As of Ansible 2.3, the I(name) option has been changed to I(path) as default, but I(name) still works as well.
author:
- Brian Coca (@bcoca)
'''

EXAMPLES = '''
- name: Obtain the extended attributes  of /etc/foo.conf
  xattr:
    path: /etc/foo.conf

- name: Set the key 'user.foo' to value 'bar'
  xattr:
    path: /etc/foo.conf
    key: foo
    value: bar

- name: Set the key 'trusted.glusterfs.volume-id' to value '0x817b94343f164f199e5b573b4ea1f914'
  xattr:
    path: /mnt/bricks/brick1
    namespace: trusted
    key: glusterfs.volume-id
    value: "0x817b94343f164f199e5b573b4ea1f914"

- name: Remove the key 'user.foo'
  xattr:
    path: /etc/foo.conf
    key: foo
    state: absent

- name: Remove the key 'trusted.glusterfs.volume-id'
  xattr:
    path: /mnt/bricks/brick1
    namespace: trusted
    key: glusterfs.volume-id
    state: absent
'''

import os

# import module snippets
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils._text import to_native


def get_xattr_keys(module, path, follow):
    cmd = [module.get_bin_path('getfattr', True)]
    # prevents warning and not sure why it's not default
    cmd.append('--absolute-names')
    if not follow:
        cmd.append('-h')
    cmd.append(path)

    return _run_xattr(module, cmd)


def get_xattr(module, path, key, follow):

    cmd = [module.get_bin_path('getfattr', True)]
    # prevents warning and not sure why it's not default
    cmd.append('--absolute-names')
    if not follow:
        cmd.append('-h')
    if key is None:
        cmd.append('-d')
    else:
        cmd.append('-n %s' % key)
    cmd.append(path)

    return _run_xattr(module, cmd, False)


def set_xattr(module, path, key, value, follow):

    cmd = [module.get_bin_path('setfattr', True)]
    if not follow:
        cmd.append('-h')
    cmd.append('-n %s' % key)
    cmd.append('-v %s' % value)
    cmd.append(path)

    return _run_xattr(module, cmd)


def rm_xattr(module, path, key, follow):

    cmd = [module.get_bin_path('setfattr', True)]
    if not follow:
        cmd.append('-h')
    cmd.append('-x %s' % key)
    cmd.append(path)

    return _run_xattr(module, cmd, False)


def _run_xattr(module, cmd, check_rc=True):

    try:
        (rc, out, err) = module.run_command(' '.join(cmd), check_rc=check_rc)
    except Exception as e:
        module.fail_json(msg="%s!" % to_native(e))

    # result = {'raw': out}
    result = {}
    for line in out.splitlines():
        if line.startswith('#') or line == '':
            pass
        elif '=' in line:
            (key, val) = line.split('=')
            result[key] = val.strip('"')
        else:
            result[line] = ''
    return result


def main():
    module = AnsibleModule(
        argument_spec=dict(
            path=dict(type='path', required=True, aliases=['name']),
            namespace=dict(type='str', default='user'),
            key=dict(type='str'),
            value=dict(type='str'),
            state=dict(type='str', default='read', choices=['absent', 'all', 'keys', 'present', 'read']),
            follow=dict(type='bool', default=True),
        ),
        supports_check_mode=True,
    )
    path = module.params.get('path')
    namespace = module.params.get('namespace')
    key = module.params.get('key')
    value = module.params.get('value')
    state = module.params.get('state')
    follow = module.params.get('follow')

    if not os.path.exists(path):
        module.fail_json(msg="path not found or not accessible!")

    changed = False
    msg = ""
    res = {}

    if key is None and state in ['absent', 'present']:
        module.fail_json(msg="%s needs a key parameter" % state)

    # Prepend the key with the namespace if defined
    if (
            key is not None and
            namespace is not None and
            len(namespace) > 0 and
            not (namespace == 'user' and key.startswith('user.'))):
        key = '%s.%s' % (namespace, key)

    if (state == 'present' or value is not None):
        current = get_xattr(module, path, key, follow)
        if current is None or key not in current or value != current[key]:
            if not module.check_mode:
                res = set_xattr(module, path, key, value, follow)
            changed = True
        res = current
        msg = "%s set to %s" % (key, value)
    elif state == 'absent':
        current = get_xattr(module, path, key, follow)
        if current is not None and key in current:
            if not module.check_mode:
                res = rm_xattr(module, path, key, follow)
            changed = True
        res = current
        msg = "%s removed" % (key)
    elif state == 'keys':
        res = get_xattr_keys(module, path, follow)
        msg = "returning all keys"
    elif state == 'all':
        res = get_xattr(module, path, None, follow)
        msg = "dumping all"
    else:
        res = get_xattr(module, path, key, follow)
        msg = "returning %s" % key

    module.exit_json(changed=changed, msg=msg, xattr=res)


if __name__ == '__main__':
    main()
