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

# Copyright [2010] [Anso Labs, LLC]
#
#    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

from nova import flags
from nova import utils
from nova.auth import users
from nova.compute import model
from nova.endpoint import cloud
import time

FLAGS = flags.FLAGS


class UserCommands(object):
    def __init__(self):
        self.manager = users.UserManager.instance()

    def __print_export(self, user):
        print 'export EC2_ACCESS_KEY=%s' % user.access
        print 'export EC2_SECRET_KEY=%s' % user.secret

    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)
        self.__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)
        self.__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:
            self.__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 zip(self, name, filename='nova.zip'):
        """exports credentials for user to a zip file
        arguments: name [filename='nova.zip]"""
        user = self.manager.get_user(name)
        if user:
            with open(filename, 'w') as f:
                f.write(user.get_credentials())
        else:
            print "User %s doesn't exist" % name


def usage(script_name):
    print script_name + " category action [<args>]"


categories = [
    ('user', UserCommands),
]


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)"""
    return [(k, v) for (k, v) in key_value_tuples if k.lower().find(name.lower()) == 0]


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)"""
    return [(i, getattr(obj, i)) for i in dir(obj) if callable(getattr(obj, i)) and not i.startswith('_')]


if __name__ == '__main__':
    utils.default_flagfile()
    argv = FLAGS(sys.argv)
    script_name = argv.pop(0)
    if len(argv) < 1:
        usage(script_name)
        print "Available categories:"
        for k, v in categories:
            print "\t%s" % k
        sys.exit(2)
    category = argv.pop(0)
    matches = lazy_match(category, categories)
    if len(matches) == 0:
        print "%s does not match any categories:" % category
        for k, v in categories:
            print "\t%s" % k
        sys.exit(2)
    if len(matches) > 1:
        print "%s matched multiple categories:" % category
        for k, v in matches:
            print "\t%s" % k
        sys.exit(2)
    # instantiate the command group object
    category, fn = matches[0]
    command_object = fn()
    actions = methods_of(command_object)
    if len(argv) < 1:
        usage(script_name)
        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)
    if len(matches) == 0:
        print "%s does not match any actions" % action
        for k, v in actions:
            print "\t%s" % k
        sys.exit(2)
    if len(matches) > 1:
        print "%s matched multiple actions:" % action
        for k, v in matches:
            print "\t%s" % k
        sys.exit(2)
    action, fn = matches[0]
    # call the action with the remaining arguments
    try:
        fn(*argv)
    except TypeError:
        print "Wrong number of arguments supplied"
        print "%s %s: %s" % (category, action, fn.__doc__)