#!/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 os
import sys
import time

# If ../nova/__init__.py exists, add ../ to Python search path, so that
# it will override what happens to be installed in /usr/(local/)lib/python...
possible_topdir = os.path.normpath(os.path.join(os.path.abspath(sys.argv[0]),
                                   os.pardir,
                                   os.pardir))
if os.path.exists(os.path.join(possible_topdir, 'nova', '__init__.py')):
    sys.path.insert(0, possible_topdir)

from nova import db
from nova import flags
from nova import utils
from nova.auth import manager
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.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'],
                                          check_exit_code=False)
                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 db.instance_get_all():
            if (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()