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

# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
#
# 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/>.

import shutil
import stat
import grp
import pwd
try:
    import selinux
    HAVE_SELINUX=True
except ImportError:
    HAVE_SELINUX=False

DOCUMENTATION = '''
---
module: file
version_added: "historical"
short_description: Sets attributes of files
extends_documentation_fragment: files
description: 
     - Sets attributes of files, symlinks, and directories, or removes
       files/symlinks/directories. Many other modules support the same options as
       the M(file) module - including M(copy), M(template), and M(assemble).
notes:
    - See also M(copy), M(template), M(assemble)
requirements: [ ]
author: Michael DeHaan
'''

EXAMPLES = '''
- file: path=/etc/foo.conf owner=foo group=foo mode=0644
- file: src=/file/to/link/to dest=/path/to/symlink owner=foo group=foo state=link
- file: src=/tmp/{{ item.path }} dest={{ item.dest }} state=link
  with_items:
    - { path: 'x', dest: 'y' }
    - { path: 'z', dest: 'k' }
'''

def main():

    module = AnsibleModule(
        argument_spec = dict(
            state = dict(choices=['file','directory','link','hard','touch','absent'], default=None),
            path  = dict(aliases=['dest', 'name'], required=True),
            original_basename = dict(required=False), # Internal use only, for recursive ops
            recurse  = dict(default='no', type='bool'),
            force = dict(required=False,default=False,type='bool'),
            diff_peek = dict(default=None),
            validate = dict(required=False, default=None),
            src = dict(required=False, default=None),
        ),
        add_file_common_args=True,
        supports_check_mode=True
    )

    params = module.params
    state  = params['state']
    force = params['force']
    diff_peek = params['diff_peek']
    src = params['src']

    # modify source as we later reload and pass, specially relevant when used by other modules.
    params['path'] = path = os.path.expanduser(params['path'])

    # short-circuit for diff_peek
    if diff_peek is not None:
        appears_binary = False
        try:
            f = open(path)
            b = f.read(8192)
            f.close()
            if "\x00" in b:
                appears_binary = True
        except:
            pass
        module.exit_json(path=path, changed=False, appears_binary=appears_binary)

    # Find out current state
    prev_state = 'absent'
    if os.path.lexists(path):
        if os.path.islink(path):
            prev_state = 'link'
        elif os.path.isdir(path):
            prev_state = 'directory'
        elif os.stat(path).st_nlink > 1:
            prev_state = 'hard'
        else:
            # could be many other things, but defaulting to file
            prev_state = 'file'

    # state should default to file, but since that creates many conflicts,
    # default to 'current' when it exists.
    if state is None:
        if prev_state != 'absent':
            state = prev_state
        else:
            state = 'file'

    # source is both the source of a symlink or an informational passing of the src for a template module
    # or copy module, even if this module never uses it, it is needed to key off some things
    if src is not None:
        src = os.path.expanduser(src)

        # original_basename is used by other modules that depend on file.
        if os.path.isdir(path) and state not in ["link", "absent"]:
            if params['original_basename']:
                basename = params['original_basename']
            else:
                basename = os.path.basename(src)
            params['path'] = path = os.path.join(path, basename)
    else:
        if state in ['link','hard']:
            module.fail_json(msg='src and dest are required for creating links')

    file_args = module.load_file_common_arguments(params)
    changed = False

    recurse = params['recurse']
    if recurse and state != 'directory':
        module.fail_json(path=path, msg="recurse option requires state to be 'directory'")

    if state == 'absent':
        if state != prev_state:
            if not module.check_mode:
                if prev_state == 'directory':
                    try:
                        shutil.rmtree(path, ignore_errors=False)
                    except Exception, e:
                        module.fail_json(msg="rmtree failed: %s" % str(e))
                else:
                    try:
                        os.unlink(path)
                    except Exception, e:
                        module.fail_json(path=path, msg="unlinking failed: %s " % str(e))
            module.exit_json(path=path, changed=True)
        else:
            module.exit_json(path=path, changed=False)

    elif state == 'file':
        if state != prev_state:
            # file is not absent and any other state is a conflict
            module.fail_json(path=path, msg='file (%s) is %s, cannot continue' % (path, prev_state))

        changed = module.set_fs_attributes_if_different(file_args, changed)
        module.exit_json(path=path, changed=changed)

    elif state == 'directory':
        if prev_state == 'absent':
            if module.check_mode:
                module.exit_json(changed=True)
            os.makedirs(path)
            changed = True

        changed = module.set_fs_attributes_if_different(file_args, changed)

        if recurse:
            for root,dirs,files in os.walk( file_args['path'] ):
                for fsobj in dirs + files:
                    fsname=os.path.join(root, fsobj)
                    tmp_file_args = file_args.copy()
                    tmp_file_args['path']=fsname
                    changed = module.set_fs_attributes_if_different(tmp_file_args, changed)

        module.exit_json(path=path, changed=changed)

    elif state in ['link','hard']:

        if os.path.isdir(path) and not os.path.islink(path):
            relpath = path
        else:
            relpath = os.path.dirname(path)

        absrc = os.path.normpath('%s/%s' % (relpath, os.path.basename(src)))
        if not os.path.exists(src) and not os.path.exists(absrc) and not force:
            module.fail_json(path=path, src=src, msg='src file does not exist, use "force=yes" if you really want to create the link: %s' % absrc)

        if state == 'hard':
            if not os.path.isabs(src):
                module.fail_json(msg="absolute paths are required")
        elif prev_state == 'directory':
            if not force:
                module.fail_json(path=path, msg='refusing to convert between %s and %s for %s' % (prev_state, state, src))
            elif len(os.listdir(path)) > 0:
                # refuse to replace a directory that has files in it
                module.fail_json(path=path, msg='the directory %s is not empty, refusing to convert it' % path)
        elif prev_state in ['file', 'hard'] and not force:
            module.fail_json(path=path, msg='refusing to convert between %s and %s for %s' % (prev_state, state, src))

        if prev_state == 'absent':
            changed = True
        elif prev_state == 'link':
            old_src = os.readlink(path)
            if old_src != src:
                changed = True
        elif prev_state == 'hard':
            if not (state == 'hard' and os.stat(path).st_ino == os.stat(src).st_ino):
                changed = True
                if not force:
                    module.fail_json(dest=path, src=src, msg='Cannot link, different hard link exists at destination')
        elif prev_state in ['file', 'directory']:
            changed = True
            if not force:
                module.fail_json(dest=path, src=src, msg='Cannot link, %s exists at destination' % prev_state)
        else:
            module.fail_json(dest=path, src=src, msg='unexpected position reached')

        if changed and not module.check_mode:
            if prev_state != 'absent':
                # try to replace atomically
                tmppath = '/'.join([os.path.dirname(path), ".%s.%s.tmp" % (os.getpid(),time.time())])
                try:
                    if state == 'hard':
                        os.link(src,tmppath)
                    else:
                        os.symlink(src, tmppath)
                    os.rename(tmppath, path)
                except OSError, e:
                    if os.path.exists(tmppath):
                        os.unlink(tmppath)
                    module.fail_json(path=path, msg='Error while replacing: %s' % str(e))
            else:
                try:
                    if state == 'hard':
                        os.link(src,path)
                    else:
                        os.symlink(src, path)
                except OSError, e:
                    module.fail_json(path=path, msg='Error while linking: %s' % str(e))

        changed = module.set_fs_attributes_if_different(file_args, changed)
        module.exit_json(dest=path, src=src, changed=changed)

    elif state == 'touch':
        if not module.check_mode:

            if prev_state == 'absent':
                try:
                    open(path, 'w').close()
                except OSError, e:
                    module.fail_json(path=path, msg='Error, could not touch target: %s' % str(e))
            elif prev_state in ['file', 'directory']:
                try:
                    os.utime(path, None)
                except OSError, e:
                    module.fail_json(path=path, msg='Error while touching existing target: %s' % str(e))
            else:
                module.fail_json(msg='Cannot touch other than files and directories')

            module.set_fs_attributes_if_different(file_args, True)

        module.exit_json(dest=path, changed=True)

    module.fail_json(path=path, msg='unexpected position reached')

# import module snippets
from ansible.module_utils.basic import *
main()

