#!/usr/bin/env python

# (c) 2014, James Tanner <tanner.jc@gmail.com>
#
# 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/>.
#
# ansible-pull is a script that runs ansible in local mode
# after checking out a playbooks directory from source repo.  There is an
# example playbook to bootstrap this script in the examples/ dir which
# installs ansible and sets it up to run on cron.

import os
import sys
import traceback

from ansible import utils
from ansible import errors
from ansible.utils.vault import VaultEditor

from optparse import OptionParser

#-------------------------------------------------------------------------------------
# Utility functions for parsing actions/options
#-------------------------------------------------------------------------------------

VALID_ACTIONS = ("create", "decrypt", "edit", "encrypt", "rekey")

def build_option_parser(action):
    """
    Builds an option parser object based on the action
    the user wants to execute.
    """

    usage = "usage: %%prog [%s] [--help] [options] file_name" % "|".join(VALID_ACTIONS)
    epilog = "\nSee '%s <command> --help' for more information on a specific command.\n\n" % os.path.basename(sys.argv[0])
    OptionParser.format_epilog = lambda self, formatter: self.epilog
    parser = OptionParser(usage=usage, epilog=epilog)

    if not action:
        parser.print_help()
        sys.exit()

    # options for all actions
    #parser.add_option('-c', '--cipher', dest='cipher', default="AES256", help="cipher to use")
    parser.add_option('--debug', dest='debug', action="store_true", help="debug")
    parser.add_option('--vault-password-file', dest='password_file',
                    help="vault password file")

    # options specific to actions
    if action == "create":
        parser.set_usage("usage: %prog create [options] file_name")
    elif action == "decrypt":
        parser.set_usage("usage: %prog decrypt [options] file_name")
    elif action == "edit":
        parser.set_usage("usage: %prog edit [options] file_name")
    elif action == "encrypt":
        parser.set_usage("usage: %prog encrypt [options] file_name")
    elif action == "rekey":
        parser.set_usage("usage: %prog rekey [options] file_name")
    
    # done, return the parser
    return parser

def get_action(args):
    """
    Get the action the user wants to execute from the 
    sys argv list.
    """
    for i in range(0,len(args)):
        arg = args[i]
        if arg in VALID_ACTIONS:
            del args[i]
            return arg
    return None

def get_opt(options, k, defval=""):
    """
    Returns an option from an Optparse values instance.
    """
    try:
        data = getattr(options, k)
    except:
        return defval
    if k == "roles_path":
        if os.pathsep in data:
            data = data.split(os.pathsep)[0]
    return data

#-------------------------------------------------------------------------------------
# Command functions
#-------------------------------------------------------------------------------------

def _read_password(filename):
    f = open(filename, "rb")
    data = f.read()
    f.close
    return data

def execute_create(args, options, parser):

    if len(args) > 1:
        raise errors.AnsibleError("'create' does not accept more than one filename")        

    if not options.password_file:        
        password, new_password = utils.ask_vault_passwords(ask_vault_pass=True, confirm_vault=True)
    else:
        password = _read_password(options.password_file)

    cipher = 'AES256'
    if hasattr(options, 'cipher'):
        cipher = options.cipher

    this_editor = VaultEditor(cipher, password, args[0])
    this_editor.create_file()

def execute_decrypt(args, options, parser):

    if not options.password_file:        
        password, new_password = utils.ask_vault_passwords(ask_vault_pass=True)
    else:
        password = _read_password(options.password_file)

    cipher = 'AES256'
    if hasattr(options, 'cipher'):
        cipher = options.cipher

    for f in args:
        this_editor = VaultEditor(cipher, password, f)
        this_editor.decrypt_file()

    print "Decryption successful"

def execute_edit(args, options, parser):

    if len(args) > 1:
        raise errors.AnsibleError("create does not accept more than one filename")        

    if not options.password_file:        
        password, new_password = utils.ask_vault_passwords(ask_vault_pass=True)
    else:
        password = _read_password(options.password_file)

    cipher = None

    for f in args:
        this_editor = VaultEditor(cipher, password, f)
        this_editor.edit_file()

def execute_encrypt(args, options, parser):

    if len(args) > 1:
        raise errors.AnsibleError("'create' does not accept more than one filename")        

    if not options.password_file:        
        password, new_password = utils.ask_vault_passwords(ask_vault_pass=True, confirm_vault=True)
    else:
        password = _read_password(options.password_file)

    cipher = 'AES256'
    if hasattr(options, 'cipher'):
        cipher = options.cipher

    for f in args:
        this_editor = VaultEditor(cipher, password, f)
        this_editor.encrypt_file()

    print "Encryption successful"

def execute_rekey(args, options, parser):

    if not options.password_file:        
        password, __ = utils.ask_vault_passwords(ask_vault_pass=True)
    else:
        password = _read_password(options.password_file)

    __, new_password = utils.ask_vault_passwords(ask_vault_pass=False, ask_new_vault_pass=True, confirm_new=True)

    cipher = None
    for f in args:
        this_editor = VaultEditor(cipher, password, f)
        this_editor.rekey_file(new_password)

    print "Rekey successful"

#-------------------------------------------------------------------------------------
# MAIN
#-------------------------------------------------------------------------------------

def main():

    action = get_action(sys.argv)
    parser = build_option_parser(action)
    (options, args) = parser.parse_args()

    # execute the desired action
    try:
        fn = globals()["execute_%s" % action]
        fn(args, options, parser)
    except Exception, err:
        if options.debug:
            print traceback.format_exc()
        print "ERROR:",err
        sys.exit(1)

if __name__ == "__main__":
    main()