#!/usr/bin/env python
# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

"""
  CLI interface for nova management.
  Connects to the running ADMIN api in the api daemon.
"""

import sys
import time

from nova import flags
from nova import utils
from nova.auth import manager
from nova.compute import model
from nova.cloudpipe import pipelib
from nova.endpoint import cloud


FLAGS = flags.FLAGS


class VpnCommands(object):
    """Class for managing VPNs."""

    def __init__(self):
        self.manager = manager.AuthManager()
        self.instdir = model.InstanceDirectory()
        self.pipe = pipelib.CloudPipe(cloud.CloudController())

    def list(self):
        """Print a listing of the VPNs for all projects."""
        print "%-12s\t" % 'project',
        print "%-12s\t" % 'ip:port',
        print "%s" % 'state'
        for project in self.manager.get_projects():
            print "%-12s\t" % project.name,
            print "%s:%s\t" % (project.vpn_ip, project.vpn_port),

            vpn = self._vpn_for(project.id)
            if vpn:
                command = "ping -c1 -w1 %s > /dev/null; echo $?"
                out, _err = utils.execute(command % vpn['private_dns_name'])
                if out.strip() == '0':
                    net = 'up'
                else:
                    net = 'down'
                print vpn['private_dns_name'],
                print vpn['node_name'],
                print vpn['instance_id'],
                print vpn['state_description'],
                print net

            else:
                print None

    def _vpn_for(self, project_id):
        """Get the VPN instance for a project ID."""
        for instance in self.instdir.all:
            if ('image_id' in instance.state
                and instance['image_id'] == FLAGS.vpn_image_id
                and not instance['state_description'] in
                    ['shutting_down', 'shutdown']
                and instance['project_id'] == project_id):
                return instance

    def spawn(self):
        """Run all VPNs."""
        for p in reversed(self.manager.get_projects()):
            if not self._vpn_for(p.id):
                print 'spawning %s' % p.id
                self.pipe.launch_vpn_instance(p.id)
                time.sleep(10)

    def run(self, project_id):
        """Start the VPN for a given project."""
        self.pipe.launch_vpn_instance(project_id)


class RoleCommands(object):
    """Class for managing roles."""

    def __init__(self):
        self.manager = manager.AuthManager()

    def add(self, user, role, project=None):
        """adds role to user
        if project is specified, adds project specific role
        arguments: user, role [project]"""
        self.manager.add_role(user, role, project)

    def has(self, user, role, project=None):
        """checks to see if user has role
        if project is specified, returns True if user has
        the global role and the project role
        arguments: user, role [project]"""
        print self.manager.has_role(user, role, project)

    def remove(self, user, role, project=None):
        """removes role from user
        if project is specified, removes project specific role
        arguments: user, role [project]"""
        self.manager.remove_role(user, role, project)


class UserCommands(object):
    """Class for managing users."""

    def __init__(self):
        self.manager = manager.AuthManager()

    def admin(self, name, access=None, secret=None):
        """creates a new admin and prints exports
        arguments: name [access] [secret]"""
        user = self.manager.create_user(name, access, secret, True)
        print_export(user)

    def create(self, name, access=None, secret=None):
        """creates a new user and prints exports
        arguments: name [access] [secret]"""
        user = self.manager.create_user(name, access, secret, False)
        print_export(user)

    def delete(self, name):
        """deletes an existing user
        arguments: name"""
        self.manager.delete_user(name)

    def exports(self, name):
        """prints access and secrets for user in export format
        arguments: name"""
        user = self.manager.get_user(name)
        if user:
            print_export(user)
        else:
            print "User %s doesn't exist" % name

    def list(self):
        """lists all users
        arguments: <none>"""
        for user in self.manager.get_users():
            print user.name


def print_export(user):
    """Print export variables to use with API."""
    print 'export EC2_ACCESS_KEY=%s' % user.access
    print 'export EC2_SECRET_KEY=%s' % user.secret


class ProjectCommands(object):
    """Class for managing projects."""

    def __init__(self):
        self.manager = manager.AuthManager()

    def add(self, project, user):
        """Adds user to project
        arguments: project user"""
        self.manager.add_to_project(user, project)

    def create(self, name, project_manager, description=None):
        """Creates a new project
        arguments: name project_manager [description]"""
        self.manager.create_project(name, project_manager, description)

    def delete(self, name):
        """Deletes an existing project
        arguments: name"""
        self.manager.delete_project(name)

    def environment(self, project_id, user_id, filename='novarc'):
        """Exports environment variables to an sourcable file
        arguments: project_id user_id [filename='novarc]"""
        rc = self.manager.get_environment_rc(project_id, user_id)
        with open(filename, 'w') as f:
            f.write(rc)

    def list(self):
        """Lists all projects
        arguments: <none>"""
        for project in self.manager.get_projects():
            print project.name

    def remove(self, project, user):
        """Removes user from project
        arguments: project user"""
        self.manager.remove_from_project(user, project)

    def zipfile(self, project_id, user_id, filename='nova.zip'):
        """Exports credentials for project to a zip file
        arguments: project_id user_id [filename='nova.zip]"""
        zip_file = self.manager.get_credentials(user_id, project_id)
        with open(filename, 'w') as f:
            f.write(zip_file)


categories = [
    ('user', UserCommands),
    ('project', ProjectCommands),
    ('role', RoleCommands),
    ('vpn', VpnCommands),
]


def lazy_match(name, key_value_tuples):
    """Finds all objects that have a key that case insensitively contains
    [name] key_value_tuples is a list of tuples of the form (key, value)
    returns a list of tuples of the form (key, value)"""
    result = []
    for (k, v) in key_value_tuples:
        if k.lower().find(name.lower()) == 0:
            result.append((k, v))
    if len(result) == 0:
        print "%s does not match any options:" % name
        for k, _v in key_value_tuples:
            print "\t%s" % k
        sys.exit(2)
    if len(result) > 1:
        print "%s matched multiple options:" % name
        for k, _v in result:
            print "\t%s" % k
        sys.exit(2)
    return result


def methods_of(obj):
    """Get all callable methods of an object that don't start with underscore
    returns a list of tuples of the form (method_name, method)"""
    result = []
    for i in dir(obj):
        if callable(getattr(obj, i)) and not i.startswith('_'):
            result.append((i, getattr(obj, i)))
    return result


def main():
    """Parse options and call the appropriate class/method."""
    utils.default_flagfile('/etc/nova/nova-manage.conf')
    argv = FLAGS(sys.argv)
    script_name = argv.pop(0)
    if len(argv) < 1:
        print script_name + " category action [<args>]"
        print "Available categories:"
        for k, _ in categories:
            print "\t%s" % k
        sys.exit(2)
    category = argv.pop(0)
    matches = lazy_match(category, categories)
    # instantiate the command group object
    category, fn = matches[0]
    command_object = fn()
    actions = methods_of(command_object)
    if len(argv) < 1:
        print script_name + " category action [<args>]"
        print "Available actions for %s category:" % category
        for k, _v in actions:
            print "\t%s" % k
        sys.exit(2)
    action = argv.pop(0)
    matches = lazy_match(action, actions)
    action, fn = matches[0]
    # call the action with the remaining arguments
    try:
        fn(*argv)
        sys.exit(0)
    except TypeError:
        print "Wrong number of arguments supplied"
        print "%s %s: %s" % (category, action, fn.__doc__)
        sys.exit(2)

if __name__ == '__main__':
    main()