#!/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 os
import shutil
import time

DOCUMENTATION = '''
---
module: copy
short_description: Copies files to remote locations.
description:
     - The M(copy) module copies a file on the local box to remote locations.
options:
  src:
    description:
      - Local path to a file to copy to the remote server; can be absolute or relative.
    required: true
    default: null
    aliases: []
  dest:
    description:
      - Remote absolute path where the file should be copied to.
    required: true
    default: null
  backup:
    description:
      - Create a backup file including the timestamp information so you can get
        the original file back if you somehow clobbered it incorrectly.
    version_added: "0.7"
    required: false
    choices: [ "yes", "no" ]
    default: "no"
  force:
    description:
      - the default is C(yes), which will replace the remote file when contents
        are different than the source.  If C(no), the file will only be transferred
        if the destination does not exist.
    version_added: "1.1"
    required: false
    choices: [ "yes", "no" ]
    default: "yes"
    aliases: [ "thirsty" ]
  others:
  others:
    description:
      - all arguments accepted by the M(file) module also work here
    required: false
examples:
   - code: "copy: src=/srv/myfiles/foo.conf dest=/etc/foo.conf owner=foo group=foo mode=0644"
     description: "Example from Ansible Playbooks"
   - code: "copy: src=/mine/ntp.conf dest=/etc/ntp.conf owner=root group=root mode=644 backup=yes"
     description: "Copy a new C(ntp.conf) file into place, backing up the original if it differs from the copied version"
author: Michael DeHaan
'''

def main():

    module = AnsibleModule(
        # not checking because of daisy chain to file module
        argument_spec = dict(
            src=dict(required=True),
            dest=dict(required=True),
            backup=dict(default=False, type='bool'),
            force = dict(default='yes', aliases=['thirsty'], type='bool'),
        ),
        add_file_common_args=True,
    )

    src  = os.path.expanduser(module.params['src'])
    dest = os.path.expanduser(module.params['dest'])
    backup = module.params['backup']
    force = module.params['force']

    if not os.path.exists(src):
        module.fail_json(msg="Source %s failed to transfer" % (src))
    if not os.access(src, os.R_OK):
        module.fail_json(msg="Source %s not readable" % (src))

    md5sum_src = module.md5(src)
    md5sum_dest = None

    if os.path.exists(dest):
        if not force:
            module.exit_json(msg="file already exists", src=src, dest=dest, changed=False)
        if (os.path.isdir(dest)):
            basename = os.path.basename(src)
            dest = os.path.join(dest, basename)
        if os.access(dest, os.R_OK):
            md5sum_dest = module.md5(dest)
    else:
        if not os.path.exists(os.path.dirname(dest)):
            module.fail_json(msg="Destination directory %s does not exist" % (os.path.dirname(dest)))
    if not os.access(os.path.dirname(dest), os.W_OK):
        module.fail_json(msg="Destination %s not writable" % (os.path.dirname(dest)))

    backup_file = None
    if md5sum_src != md5sum_dest or os.path.islink(dest):
        try:
            if backup:
                if os.path.exists(dest):
                    backup_file = module.backup_local(dest)
            # allow for conversion from symlink.
            if os.path.islink(dest):
                os.unlink(dest)
                open(dest, 'w').close()
            #TODO:pid + epoch should avoid most collisions, hostname/mac for those using nfs?
            # might be an issue with exceeding path length
            dest_tmp = "%s.%s.%s.tmp" % (dest,os.getpid(),time.time())
            shutil.copyfile(src, dest_tmp)
            module.atomic_replace(dest_tmp, dest)
        except shutil.Error:
            module.fail_json(msg="failed to copy: %s and %s are the same" % (src, dest))
        except IOError:
            module.fail_json(msg="failed to copy: %s to %s" % (src, dest))
        changed = True
    else:
        changed = False

    res_args = dict(
        dest = dest, src = src, md5sum = md5sum_src, changed = changed
    )
    if backup_file:
        res_args['backup_file'] = backup_file

    module.params['dest'] = dest
    file_args = module.load_file_common_arguments(module.params)
    res_args['changed'] = module.set_file_attributes_if_different(file_args, res_args['changed'])

    module.exit_json(**res_args)

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()