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

# (c) 2013, Johan Wiren <johan.wiren.se@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/>.
#

DOCUMENTATION = '''
---
module: gem
short_description: Manage Ruby gems
description: 
  - Manage installation and uninstallation of Ruby gems.
version_added: "1.1"
options:
  name:
    description: The name of the gem to be managed.
    required: true
  state:
    description: The desired state of the gem. C(latest) ensures that the latest version is installed.
    required: true
    choices: [present, absent, latest]
  gemsource:
    description: The path to a local gem used as installation source.
    required: false
  http-proxy:
    description: HTTP Proxy for remote operations.
    required: false
  includedependencies:
    description: Wheter to include dependencies or not.
    required: false
    choices: [true, false]
    default: true
  repository:
    description: The repository from which the gem will be installed
    required: false
    aliases: [source]
  version:
    description: Version of the gem to be installed/removed.
    required: false
examples:
  - code: gem name=vagrant version=1.0 state=present
    description: Installs version 1.0 of vagrant.
  - code: gem name=rake state=latest
    description: Installs latest available version of rake.
  - code: gem name=rake gemsource=/path/to/gems/rake-1.0.gem state=present
    description: Installs rake version 1.0 from a local gem on disk.
author: Johan Wiren
'''
import re
from urlparse import urlparse

def getinstalledversions(module, remote=False):
    cmd = [ module.get_bin_path('gem', True) ]
    cmd.append('query')
    if remote:
        cmd.append('--remote')
        if module.params['http-proxy']:
            cmd.extend([ '--http-proxy', module.params['http-proxy'] ])
        if module.params['repository']:
            cmd.extend([ '--source', module.params['repository'] ])
    cmd.append('-n')
    cmd.append('^%s$' % module.params['name'])
    (rc, out, err) = module.run_command(cmd, check_rc=True)
    installedversions = []
    for line in out.splitlines():
        match = re.match(r"\S+\s+\((.+)\)", line)
        if match:
            versions = match.group(1)
            for version in versions.split(', '):
                installedversions.append(version)
    return installedversions

def exists(module):
    if module.params['state'] == 'latest':
        remoteversions = getinstalledversions(module, remote=True)
        if remoteversions:
            module.params['version'] = remoteversions[0]
    installedversions = getinstalledversions(module)
    if module.params['version']:
        if module.params['version'] in installedversions:
            return True
    else:
        if installedversions:
            return True
    return False

def uninstall(module):
    if module.check_mode:
        return
    cmd = [ module.get_bin_path('gem', True) ]
    cmd.append('uninstall')
    if module.params['version']:
        cmd.extend([ '--version', module.params['version'] ])
    else:
        cmd.append('--all')
    cmd.append(module.params['name'])
    module.run_command(cmd, check_rc=True)

def install(module):
    if module.check_mode:
        return
    cmd = [ module.get_bin_path('gem', True) ]
    cmd.append('install')
    if module.params['version']:
        cmd.extend([ '--version', module.params['version'] ])
    if module.params['repository']:
        cmd.extend([ '--source', module.params['repository'] ])
    if module.params['http-proxy']:
        cmd.extend([ '--http-proxy', module.params['http-proxy'] ])
    if module.params['includedependencies']:
        cmd.append('--include-dependencies')
    cmd.append('--no-rdoc')
    cmd.append('--no-ri')
    cmd.append(module.params['gemsource'])
    module.run_command(cmd, check_rc=True)

def main():
    module = AnsibleModule(
        argument_spec = {
            'gemsource':           {'required': False},
            'http-proxy':          {'required': False},
            'includedependencies': {'required': False, 'default':True,  'choices':BOOLEANS},
            'name':                {'required': True},
            'repository':          {'required': False, 'aliases':['source']},
            'state':               {'required': True, 'choices':['present', 'absent', 'latest']},
            'version':             {'required': False},
            },
        supports_check_mode = True,
        mutually_exclusive = [ [ 'gemsource', 'repository' ], [ 'gemsource', 'version' ] ],
        )

    if module.params['version'] and module.params['state'] == 'latest':
        module.fail_json(msg="Cannot specify version when state=latest")
    if module.params['gemsource'] and module.params['state'] == 'latest':
        module.fail_json(msg="Cannot maintain state=latest when installing from local source")

    if module.params['gemsource']:
        url=urlparse(module.params['gemsource'])
        if url.scheme in [ '', 'file' ] :
            module.params['gemsource'] = url.path
        else:
            module.fail_json(msg="Installation using url scheme %s is not supported." % url.scheme)
    else:
        module.params['gemsource'] = module.params['name']

    changed = False

    if module.params['state'] in [ 'present', 'latest' ]:
        if not exists(module):
            install(module)
            changed = True
    elif module.params['state'] == 'absent':
        if exists(module):
            uninstall(module)
            changed = True

    result = {}
    result['name'] = module.params['name']
    result['state'] = module.params['state']
    if module.params['version']:
        result['version'] = module.params['version']
    result['changed'] = changed

    module.exit_json(**result)

# include magic from lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()