#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# (c) 2015, René Moser <mail@renemoser.net>
#
# 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: cs_securitygroup_rule
short_description: Manages security group rules on Apache CloudStack based clouds.
description:
    - Add and remove security group rules.
version_added: '2.0'
author: "René Moser (@resmo)"
options:
  security_group:
    description:
      - Name of the security group the rule is related to. The security group must be existing.
    required: true
  state:
    description:
      - State of the security group rule.
    required: false
    default: 'present'
    choices: [ 'present', 'absent' ]
  protocol:
    description:
      - Protocol of the security group rule.
    required: false
    default: 'tcp'
    choices: [ 'tcp', 'udp', 'icmp', 'ah', 'esp', 'gre' ]
  type:
    description:
      - Ingress or egress security group rule.
    required: false
    default: 'ingress'
    choices: [ 'ingress', 'egress' ]
  cidr:
    description:
      - CIDR (full notation) to be used for security group rule.
    required: false
    default: '0.0.0.0/0'
  user_security_group:
    description:
      - Security group this rule is based of.
    required: false
    default: null
  start_port:
    description:
      - Start port for this rule. Required if C(protocol=tcp) or C(protocol=udp).
    required: false
    default: null
    aliases: [ 'port' ]
  end_port:
    description:
      - End port for this rule. Required if C(protocol=tcp) or C(protocol=udp), but C(start_port) will be used if not set.
    required: false
    default: null
  icmp_type:
    description:
      - Type of the icmp message being sent. Required if C(protocol=icmp).
    required: false
    default: null
  icmp_code:
    description:
      - Error code for this icmp message. Required if C(protocol=icmp).
    required: false
    default: null
  project:
    description:
      - Name of the project the security group to be created in.
    required: false
    default: null
  poll_async:
    description:
      - Poll async jobs until job has finished.
    required: false
    default: true
extends_documentation_fragment: cloudstack
'''

EXAMPLES = '''
---
# Allow inbound port 80/tcp from 1.2.3.4 added to security group 'default'
- local_action:
    module: cs_securitygroup_rule
    security_group: default
    port: 80
    cidr: 1.2.3.4/32

# Allow tcp/udp outbound added to security group 'default'
- local_action:
    module: cs_securitygroup_rule
    security_group: default
    type: egress
    start_port: 1
    end_port: 65535
    protocol: '{{ item }}'
  with_items:
  - tcp
  - udp

# Allow inbound icmp from 0.0.0.0/0 added to security group 'default'
- local_action:
    module: cs_securitygroup_rule
    security_group: default
    protocol: icmp
    icmp_code: -1
    icmp_type: -1

# Remove rule inbound port 80/tcp from 0.0.0.0/0 from security group 'default'
- local_action:
    module: cs_securitygroup_rule
    security_group: default
    port: 80
    state: absent

# Allow inbound port 80/tcp from security group web added to security group 'default'
- local_action:
    module: cs_securitygroup_rule
    security_group: default
    port: 80
    user_security_group: web
'''

RETURN = '''
---
id:
  description: UUID of the of the rule.
  returned: success
  type: string
  sample: a6f7a5fc-43f8-11e5-a151-feff819cdc9f
security_group:
  description: security group of the rule.
  returned: success
  type: string
  sample: default
type:
  description: type of the rule.
  returned: success
  type: string
  sample: ingress
cidr:
  description: CIDR of the rule.
  returned: success and cidr is defined
  type: string
  sample: 0.0.0.0/0
user_security_group:
  description: user security group of the rule.
  returned: success and user_security_group is defined
  type: string
  sample: default
protocol:
  description: protocol of the rule.
  returned: success
  type: string
  sample: tcp
start_port:
  description: start port of the rule.
  returned: success
  type: int
  sample: 80
end_port:
  description: end port of the rule.
  returned: success
  type: int
  sample: 80
'''

try:
    from cs import CloudStack, CloudStackException, read_config
    has_lib_cs = True
except ImportError:
    has_lib_cs = False

# import cloudstack common
from ansible.module_utils.cloudstack import *


class AnsibleCloudStackSecurityGroupRule(AnsibleCloudStack):

    def __init__(self, module):
        super(AnsibleCloudStackSecurityGroupRule, self).__init__(module)
        self.returns = {
            'icmptype':             'icmp_type',
            'icmpcode':             'icmp_code',
            'endport':              'end_port',
            'startport':            'start_port',
            'protocol':             'protocol',
            'cidr':                 'cidr',
            'securitygroupname':    'user_security_group',
        }


    def _tcp_udp_match(self, rule, protocol, start_port, end_port):
        return protocol in ['tcp', 'udp'] \
               and protocol == rule['protocol'] \
               and start_port == int(rule['startport']) \
               and end_port == int(rule['endport'])


    def _icmp_match(self, rule, protocol, icmp_code, icmp_type):
        return protocol == 'icmp' \
               and protocol == rule['protocol'] \
               and icmp_code == int(rule['icmpcode']) \
               and icmp_type == int(rule['icmptype'])


    def _ah_esp_gre_match(self, rule, protocol):
        return protocol in ['ah', 'esp', 'gre'] \
               and protocol == rule['protocol']


    def _type_security_group_match(self, rule, security_group_name):
        return security_group_name \
               and 'securitygroupname' in rule \
               and security_group_name == rule['securitygroupname']


    def _type_cidr_match(self, rule, cidr):
        return 'cidr' in rule \
               and cidr == rule['cidr']


    def _get_rule(self, rules):
        user_security_group_name = self.module.params.get('user_security_group')
        cidr                     = self.module.params.get('cidr')
        protocol                 = self.module.params.get('protocol')
        start_port               = self.module.params.get('start_port')
        end_port                 = self.get_or_fallback('end_port', 'start_port')
        icmp_code                = self.module.params.get('icmp_code')
        icmp_type                = self.module.params.get('icmp_type')

        if protocol in ['tcp', 'udp'] and not (start_port and end_port):
            self.module.fail_json(msg="no start_port or end_port set for protocol '%s'" % protocol)

        if protocol == 'icmp' and not (icmp_type and icmp_code):
            self.module.fail_json(msg="no icmp_type or icmp_code set for protocol '%s'" % protocol)

        for rule in rules:
            if user_security_group_name:
                type_match = self._type_security_group_match(rule, user_security_group_name)
            else:
                type_match = self._type_cidr_match(rule, cidr)

            protocol_match = (    self._tcp_udp_match(rule, protocol, start_port, end_port) \
                               or self._icmp_match(rule, protocol, icmp_code, icmp_type) \
                               or self._ah_esp_gre_match(rule, protocol)
                             )

            if type_match and protocol_match:
                return rule
        return None


    def get_security_group(self, security_group_name=None):
        if not security_group_name:
            security_group_name = self.module.params.get('security_group')
        args = {}
        args['securitygroupname'] =  security_group_name
        args['projectid'] = self.get_project('id')
        sgs = self.cs.listSecurityGroups(**args)
        if not sgs or 'securitygroup' not in sgs:
                self.module.fail_json(msg="security group '%s' not found" % security_group_name)
        return sgs['securitygroup'][0]


    def add_rule(self):
        security_group = self.get_security_group()

        args = {}
        user_security_group_name = self.module.params.get('user_security_group')

        # the user_security_group and cidr are mutually_exclusive, but cidr is defaulted to 0.0.0.0/0.
        # that is why we ignore if we have a user_security_group.
        if user_security_group_name:
            args['usersecuritygrouplist'] = []
            user_security_group = self.get_security_group(user_security_group_name)
            args['usersecuritygrouplist'].append({
                'group': user_security_group['name'],
                'account': user_security_group['account'],
            })
        else:
            args['cidrlist'] = self.module.params.get('cidr')

        args['protocol']        = self.module.params.get('protocol')
        args['startport']       = self.module.params.get('start_port')
        args['endport']         = self.get_or_fallback('end_port', 'start_port')
        args['icmptype']        = self.module.params.get('icmp_type')
        args['icmpcode']        = self.module.params.get('icmp_code')
        args['projectid']       = self.get_project('id')
        args['securitygroupid'] = security_group['id']

        rule = None
        res  = None
        sg_type = self.module.params.get('type')
        if sg_type == 'ingress':
            if 'ingressrule' in security_group:
                rule = self._get_rule(security_group['ingressrule'])
            if not rule:
                self.result['changed'] = True
                if not self.module.check_mode:
                    res = self.cs.authorizeSecurityGroupIngress(**args)

        elif sg_type == 'egress':
            if 'egressrule' in security_group:
                rule = self._get_rule(security_group['egressrule'])
            if not rule:
                self.result['changed'] = True
                if not self.module.check_mode:
                    res = self.cs.authorizeSecurityGroupEgress(**args)

        if res and 'errortext' in res:
            self.module.fail_json(msg="Failed: '%s'" % res['errortext'])

        poll_async = self.module.params.get('poll_async')
        if res and poll_async:
            security_group = self._poll_job(res, 'securitygroup')
            key = sg_type + "rule" # ingressrule / egressrule
            if key in security_group:
                rule = security_group[key][0]
        return rule


    def remove_rule(self):
        security_group = self.get_security_group()
        rule = None
        res  = None
        sg_type = self.module.params.get('type')
        if sg_type == 'ingress':
            rule = self._get_rule(security_group['ingressrule'])
            if rule:
                self.result['changed'] = True
                if not self.module.check_mode:
                    res = self.cs.revokeSecurityGroupIngress(id=rule['ruleid'])

        elif sg_type == 'egress':
            rule = self._get_rule(security_group['egressrule'])
            if rule:
                self.result['changed'] = True
                if not self.module.check_mode:
                    res = self.cs.revokeSecurityGroupEgress(id=rule['ruleid'])

        if res and 'errortext' in res:
            self.module.fail_json(msg="Failed: '%s'" % res['errortext'])

        poll_async = self.module.params.get('poll_async')
        if res and poll_async:
            res = self._poll_job(res, 'securitygroup')
        return rule


    def get_result(self, security_group_rule):
        super(AnsibleCloudStackSecurityGroupRule, self).get_result(security_group_rule)
        self.result['type'] = self.module.params.get('type')
        self.result['security_group'] = self.module.params.get('security_group')
        return self.result



def main():
    argument_spec = cs_argument_spec()
    argument_spec.update(dict(
        security_group = dict(required=True),
        type = dict(choices=['ingress', 'egress'], default='ingress'),
        cidr = dict(default='0.0.0.0/0'),
        user_security_group = dict(default=None),
        protocol = dict(choices=['tcp', 'udp', 'icmp', 'ah', 'esp', 'gre'], default='tcp'),
        icmp_type = dict(type='int', default=None),
        icmp_code = dict(type='int', default=None),
        start_port = dict(type='int', default=None, aliases=['port']),
        end_port = dict(type='int', default=None),
        state = dict(choices=['present', 'absent'], default='present'),
        project = dict(default=None),
        poll_async = dict(type='bool', default=True),
    ))
    required_together = cs_required_together()
    required_together.extend([
        ['icmp_type', 'icmp_code'],
    ])

    module = AnsibleModule(
        argument_spec=argument_spec,
        required_together=required_together,
        mutually_exclusive = (
            ['icmp_type', 'start_port'],
            ['icmp_type', 'end_port'],
            ['icmp_code', 'start_port'],
            ['icmp_code', 'end_port'],
        ),
        supports_check_mode=True
    )

    if not has_lib_cs:
        module.fail_json(msg="python library cs required: pip install cs")

    try:
        acs_sg_rule = AnsibleCloudStackSecurityGroupRule(module)

        state = module.params.get('state')
        if state in ['absent']:
            sg_rule = acs_sg_rule.remove_rule()
        else:
            sg_rule = acs_sg_rule.add_rule()

        result = acs_sg_rule.get_result(sg_rule)

    except CloudStackException as e:
        module.fail_json(msg='CloudStackException: %s' % str(e))

    module.exit_json(**result)

# import module snippets
from ansible.module_utils.basic import *
if __name__ == '__main__':
    main()
