# Copyright 2011 OpenStack LLC.
# 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.

"""
Command-line interface to the OpenStack Trove API.
"""

from __future__ import print_function

import argparse
import glob
import imp
import itertools
import os
import pkgutil
import sys
import logging

import six

import troveclient
from troveclient import client
#from troveclient import exceptions as exc
#import troveclient.extension
from troveclient.openstack.common import strutils
from troveclient.openstack.common.apiclient import exceptions as exc
from troveclient import utils
from troveclient.v1 import shell as shell_v1

DEFAULT_OS_DATABASE_API_VERSION = "1.0"
DEFAULT_TROVE_ENDPOINT_TYPE = 'publicURL'
DEFAULT_TROVE_SERVICE_TYPE = 'database'

logger = logging.getLogger(__name__)


class TroveClientArgumentParser(argparse.ArgumentParser):

    def __init__(self, *args, **kwargs):
        super(TroveClientArgumentParser, self).__init__(*args, **kwargs)

    def error(self, message):
        """error(message: string)

        Prints a usage message incorporating the message to stderr and
        exits.
        """
        self.print_usage(sys.stderr)
        #FIXME(lzyeval): if changes occur in argparse.ArgParser._check_value
        choose_from = ' (choose from'
        progparts = self.prog.partition(' ')
        self.exit(2, "error: %(errmsg)s\nTry '%(mainp)s help %(subp)s'"
                     " for more information.\n" %
                     {'errmsg': message.split(choose_from)[0],
                      'mainp': progparts[0],
                      'subp': progparts[2]})


class OpenStackTroveShell(object):

    def get_base_parser(self):
        parser = TroveClientArgumentParser(
            prog='trove',
            description=__doc__.strip(),
            epilog='See "trove help COMMAND" '
                   'for help on a specific command.',
            add_help=False,
            formatter_class=OpenStackHelpFormatter,
        )

        # Global arguments
        parser.add_argument('-h', '--help',
                            action='store_true',
                            help=argparse.SUPPRESS)

        parser.add_argument('--version',
                            action='version',
                            version=troveclient.__version__)

        parser.add_argument('--debug',
                            action='store_true',
                            default=utils.env('TROVECLIENT_DEBUG',
                                              default=False),
                            help="Print debugging output")

        parser.add_argument('--os-username',
                            metavar='<auth-user-name>',
                            default=utils.env('OS_USERNAME',
                                              'TROVE_USERNAME'),
                            help='Defaults to env[OS_USERNAME].')
        parser.add_argument('--os_username',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-password',
                            metavar='<auth-password>',
                            default=utils.env('OS_PASSWORD',
                                              'TROVE_PASSWORD'),
                            help='Defaults to env[OS_PASSWORD].')
        parser.add_argument('--os_password',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-tenant-name',
                            metavar='<auth-tenant-name>',
                            default=utils.env('OS_TENANT_NAME',
                                              'TROVE_PROJECT_ID'),
                            help='Defaults to env[OS_TENANT_NAME].')
        parser.add_argument('--os_tenant_name',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-tenant-id',
                            metavar='<auth-tenant-id>',
                            default=utils.env('OS_TENANT_ID',
                                              'TROVE_TENANT_ID'),
                            help='Defaults to env[OS_TENANT_ID].')
        parser.add_argument('--os_tenant_id',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-auth-url',
                            metavar='<auth-url>',
                            default=utils.env('OS_AUTH_URL',
                                              'TROVE_URL'),
                            help='Defaults to env[OS_AUTH_URL].')
        parser.add_argument('--os_auth_url',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-region-name',
                            metavar='<region-name>',
                            default=utils.env('OS_REGION_NAME',
                                              'TROVE_REGION_NAME'),
                            help='Defaults to env[OS_REGION_NAME].')
        parser.add_argument('--os_region_name',
                            help=argparse.SUPPRESS)

        parser.add_argument('--service-type',
                            metavar='<service-type>',
                            default=utils.env('OS_SERVICE_TYPE',
                                              'TROVE_SERVICE_TYPE'),
                            help='Defaults to database for most actions')
        parser.add_argument('--service_type',
                            help=argparse.SUPPRESS)

        parser.add_argument('--service-name',
                            metavar='<service-name>',
                            default=utils.env('TROVE_SERVICE_NAME'),
                            help='Defaults to env[TROVE_SERVICE_NAME]')
        parser.add_argument('--service_name',
                            help=argparse.SUPPRESS)

        parser.add_argument('--database-service-name',
                            metavar='<database-service-name>',
                            default=utils.env('TROVE_DATABASE_SERVICE_NAME'),
                            help='Defaults to env'
                            '[TROVE_DATABASE_SERVICE_NAME]')
        parser.add_argument('--database_service_name',
                            help=argparse.SUPPRESS)

        parser.add_argument('--endpoint-type',
                            metavar='<endpoint-type>',
                            default=utils.env('TROVE_ENDPOINT_TYPE',
                            default=DEFAULT_TROVE_ENDPOINT_TYPE),
                            help='Defaults to env[TROVE_ENDPOINT_TYPE] or '
                            + DEFAULT_TROVE_ENDPOINT_TYPE + '.')
        parser.add_argument('--endpoint_type',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-database-api-version',
                            metavar='<database-api-ver>',
                            default=utils.env('OS_DATABASE_API_VERSION',
                            default=DEFAULT_OS_DATABASE_API_VERSION),
                            help='Accepts 1,defaults '
                                 'to env[OS_DATABASE_API_VERSION].')
        parser.add_argument('--os_database_api_version',
                            help=argparse.SUPPRESS)

        parser.add_argument('--os-cacert',
                            metavar='<ca-certificate>',
                            default=utils.env('OS_CACERT', default=None),
                            help='Specify a CA bundle file to use in '
                            'verifying a TLS (https) server certificate. '
                            'Defaults to env[OS_CACERT]')

        parser.add_argument('--insecure',
                            default=utils.env('TROVECLIENT_INSECURE',
                                              default=False),
                            action='store_true',
                            help=argparse.SUPPRESS)

        parser.add_argument('--retries',
                            metavar='<retries>',
                            type=int,
                            default=0,
                            help='Number of retries.')

        # FIXME(dtroyer): The args below are here for diablo compatibility,
        #                 remove them in folsum cycle

        # alias for --os-username, left in for backwards compatibility
        parser.add_argument('--username',
                            help=argparse.SUPPRESS)

        # alias for --os-region_name, left in for backwards compatibility
        parser.add_argument('--region_name',
                            help=argparse.SUPPRESS)

        # alias for --os-password, left in for backwards compatibility
        parser.add_argument('--apikey', '--password', dest='apikey',
                            default=utils.env('TROVE_API_KEY'),
                            help=argparse.SUPPRESS)

        # alias for --os-tenant-name, left in for backward compatibility
        parser.add_argument('--projectid', '--tenant_name', dest='projectid',
                            default=utils.env('TROVE_PROJECT_ID'),
                            help=argparse.SUPPRESS)

        # alias for --os-auth-url, left in for backward compatibility
        parser.add_argument('--url', '--auth_url', dest='url',
                            default=utils.env('TROVE_URL'),
                            help=argparse.SUPPRESS)

        return parser

    def get_subcommand_parser(self, version):
        parser = self.get_base_parser()

        self.subcommands = {}
        subparsers = parser.add_subparsers(metavar='<subcommand>')

        try:
            actions_module = {
                '1.0': shell_v1,
            }[version]
        except KeyError:
            actions_module = shell_v1

        self._find_actions(subparsers, actions_module)
        self._find_actions(subparsers, self)

        for extension in self.extensions:
            self._find_actions(subparsers, extension.module)

        self._add_bash_completion_subparser(subparsers)

        return parser

    def _discover_extensions(self, version):
        extensions = []
        for name, module in itertools.chain(
                self._discover_via_python_path(version),
                self._discover_via_contrib_path(version)):

            extension = troveclient.extension.Extension(name, module)
            extensions.append(extension)

        return extensions

    def _discover_via_python_path(self, version):
        for (module_loader, name, ispkg) in pkgutil.iter_modules():
            if name.endswith('python_troveclient_ext'):
                if not hasattr(module_loader, 'load_module'):
                    # Python 2.6 compat: actually get an ImpImporter obj
                    module_loader = module_loader.find_module(name)

                module = module_loader.load_module(name)
                yield name, module

    def _discover_via_contrib_path(self, version):
        module_path = os.path.dirname(os.path.abspath(__file__))
        version_str = "v%s" % version.replace('.', '_')
        ext_path = os.path.join(module_path, version_str, 'contrib')
        ext_glob = os.path.join(ext_path, "*.py")

        for ext_path in glob.iglob(ext_glob):
            name = os.path.basename(ext_path)[:-3]

            if name == "__init__":
                continue

            module = imp.load_source(name, ext_path)
            yield name, module

    def _add_bash_completion_subparser(self, subparsers):
        subparser = subparsers.add_parser(
            'bash_completion',
            add_help=False,
            formatter_class=OpenStackHelpFormatter)

        self.subcommands['bash_completion'] = subparser
        subparser.set_defaults(func=self.do_bash_completion)

    def _find_actions(self, subparsers, actions_module):
        for attr in (a for a in dir(actions_module) if a.startswith('do_')):
            # I prefer to be hypen-separated instead of underscores.
            command = attr[3:].replace('_', '-')
            callback = getattr(actions_module, attr)
            desc = callback.__doc__ or ''
            help = desc.strip().split('\n')[0]
            arguments = getattr(callback, 'arguments', [])

            subparser = subparsers.add_parser(
                command,
                help=help,
                description=desc,
                add_help=False,
                formatter_class=OpenStackHelpFormatter)

            subparser.add_argument('-h', '--help',
                                   action='help',
                                   help=argparse.SUPPRESS,)

            self.subcommands[command] = subparser
            for (args, kwargs) in arguments:
                subparser.add_argument(*args, **kwargs)
            subparser.set_defaults(func=callback)

    def setup_debugging(self, debug):
        if not debug:
            return

        streamhandler = logging.StreamHandler()
        streamformat = "%(levelname)s (%(module)s:%(lineno)d) %(message)s"
        streamhandler.setFormatter(logging.Formatter(streamformat))
        logger.setLevel(logging.DEBUG)
        logger.addHandler(streamhandler)

    def main(self, argv):
        # Parse args once to find version and debug settings
        parser = self.get_base_parser()
        (options, args) = parser.parse_known_args(argv)
        self.setup_debugging(options.debug)

        # build available subcommands based on version
        self.extensions = self._discover_extensions(
            options.os_database_api_version)
        self._run_extension_hooks('__pre_parse_args__')

        subcommand_parser = self.get_subcommand_parser(
            options.os_database_api_version)
        self.parser = subcommand_parser

        if options.help or not argv:
            subcommand_parser.print_help()
            return 0

        args = subcommand_parser.parse_args(argv)
        self._run_extension_hooks('__post_parse_args__', args)

        # Short-circuit and deal with help right away.
        if args.func == self.do_help:
            self.do_help(args)
            return 0
        elif args.func == self.do_bash_completion:
            self.do_bash_completion(args)
            return 0

        (os_username, os_password, os_tenant_name, os_auth_url,
         os_region_name, os_tenant_id, endpoint_type, insecure,
         service_type, service_name, database_service_name,
         username, apikey, projectid, url, region_name, cacert) = (
             args.os_username, args.os_password,
             args.os_tenant_name, args.os_auth_url,
             args.os_region_name, args.os_tenant_id,
             args.endpoint_type, args.insecure,
             args.service_type, args.service_name,
             args.database_service_name, args.username,
             args.apikey, args.projectid,
             args.url, args.region_name, args.os_cacert)

        if not endpoint_type:
            endpoint_type = DEFAULT_TROVE_ENDPOINT_TYPE

        if not service_type:
            service_type = DEFAULT_TROVE_SERVICE_TYPE
            service_type = utils.get_service_type(args.func) or service_type

        #FIXME(usrleon): Here should be restrict for project id same as
        # for os_username or os_password but for compatibility it is not.

        if not utils.isunauthenticated(args.func):
            if not os_username:
                if not username:
                    raise exc.CommandError(
                        "You must provide a username "
                        "via either --os-username or env[OS_USERNAME]")
                else:
                    os_username = username

            if not os_password:
                if not apikey:
                    raise exc.CommandError("You must provide a password "
                                           "via either --os-password or via "
                                           "env[OS_PASSWORD]")
                else:
                    os_password = apikey

            if not (os_tenant_name or os_tenant_id):
                if not projectid:
                    raise exc.CommandError("You must provide a tenant_id "
                                           "via either --os-tenant-id or "
                                           "env[OS_TENANT_ID]")
                else:
                    os_tenant_name = projectid

            if not os_auth_url:
                if not url:
                    raise exc.CommandError(
                        "You must provide an auth url "
                        "via either --os-auth-url or env[OS_AUTH_URL]")
                else:
                    os_auth_url = url

            if not os_region_name and region_name:
                os_region_name = region_name

        if not (os_tenant_name or os_tenant_id):
            raise exc.CommandError(
                "You must provide a tenant_id "
                "via either --os-tenant-id or env[OS_TENANT_ID]")

        if not os_auth_url:
            raise exc.CommandError(
                "You must provide an auth url "
                "via either --os-auth-url or env[OS_AUTH_URL]")

        self.cs = client.Client(options.os_database_api_version, os_username,
                                os_password, os_tenant_name, os_auth_url,
                                insecure, region_name=os_region_name,
                                tenant_id=os_tenant_id,
                                endpoint_type=endpoint_type,
                                extensions=self.extensions,
                                service_type=service_type,
                                service_name=service_name,
                                database_service_name=database_service_name,
                                retries=options.retries,
                                http_log_debug=args.debug,
                                cacert=cacert)

        try:
            if not utils.isunauthenticated(args.func):
                self.cs.authenticate()
        except exc.Unauthorized:
            raise exc.CommandError("Invalid OpenStack Trove credentials.")
        except exc.AuthorizationFailure:
            raise exc.CommandError("Unable to authorize user")

        endpoint_api_version = self.cs.get_database_api_version_from_endpoint()
        if endpoint_api_version != options.os_database_api_version:
            msg = (("Database API version is set to %s "
                    "but you are accessing a %s endpoint. "
                    "Change its value via either --os-database-api-version "
                    "or env[OS_DATABASE_API_VERSION]")
                   % (options.os_database_api_version, endpoint_api_version))
            #raise exc.InvalidAPIVersion(msg)
            raise exc.UnsupportedVersion(msg)

        args.func(self.cs, args)

    def _run_extension_hooks(self, hook_type, *args, **kwargs):
        """Run hooks for all registered extensions."""
        for extension in self.extensions:
            extension.run_hooks(hook_type, *args, **kwargs)

    def do_bash_completion(self, args):
        """Print arguments for bash_completion.

        Prints all of the commands and options to stdout so that the
        trove.bash_completion script doesn't have to hard code them.
        """
        commands = set()
        options = set()
        for sc_str, sc in list(self.subcommands.items()):
            commands.add(sc_str)
            for option in list(sc._optionals._option_string_actions.keys()):
                options.add(option)

        commands.remove('bash-completion')
        commands.remove('bash_completion')
        print(' '.join(commands | options))

    @utils.arg('command', metavar='<subcommand>', nargs='?',
               help='Display help for <subcommand>')
    def do_help(self, args):
        """
        Display help about this program or one of its subcommands.
        """
        if args.command:
            if args.command in self.subcommands:
                self.subcommands[args.command].print_help()
            else:
                raise exc.CommandError("'%s' is not a valid subcommand" %
                                       args.command)
        else:
            self.parser.print_help()


# I'm picky about my shell help.
class OpenStackHelpFormatter(argparse.HelpFormatter):
    def start_section(self, heading):
        # Title-case the headings
        heading = '%s%s' % (heading[0].upper(), heading[1:])
        super(OpenStackHelpFormatter, self).start_section(heading)


def main():
    try:
        if sys.version_info >= (3, 0):
            OpenStackTroveShell().main(sys.argv[1:])
        else:
            OpenStackTroveShell().main(map(strutils.safe_decode,
                                           sys.argv[1:]))
    except KeyboardInterrupt:
        print("... terminating trove client", file=sys.stderr)
        sys.exit(130)
    except Exception as e:
        logger.debug(e, exc_info=1)
        message = e.message
        if not isinstance(message, six.string_types):
            message = str(message)
        print("ERROR: %s" % strutils.safe_encode(message), file=sys.stderr)
        sys.exit(1)


if __name__ == "__main__":
    main()