#   Copyright 2012-2013 OpenStack Foundation
#
#   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 APIs"""

import getpass
import logging
import sys
import traceback

from cliff import app
from cliff import command
from cliff import help

import openstackclient
from openstackclient.common import clientmanager
from openstackclient.common import commandmanager
from openstackclient.common import exceptions as exc
from openstackclient.common import timing
from openstackclient.common import utils


DEFAULT_DOMAIN = 'default'


def prompt_for_password(prompt=None):
    """Prompt user for a password

    Propmpt for a password if stdin is a tty.
    """

    if not prompt:
        prompt = 'Password: '
    pw = None
    # If stdin is a tty, try prompting for the password
    if hasattr(sys.stdin, 'isatty') and sys.stdin.isatty():
        # Check for Ctl-D
        try:
            pw = getpass.getpass(prompt)
        except EOFError:
            pass
    # No password because we did't have a tty or nothing was entered
    if not pw:
        raise exc.CommandError(
            "No password entered, or found via --os-password or OS_PASSWORD",
        )
    return pw


class OpenStackShell(app.App):

    CONSOLE_MESSAGE_FORMAT = '%(levelname)s: %(name)s %(message)s'

    log = logging.getLogger(__name__)
    timing_data = []

    def __init__(self):
        # Patch command.Command to add a default auth_required = True
        command.Command.auth_required = True

        # Some commands do not need authentication
        help.HelpCommand.auth_required = False

        super(OpenStackShell, self).__init__(
            description=__doc__.strip(),
            version=openstackclient.__version__,
            command_manager=commandmanager.CommandManager('openstack.cli'))

        self.api_version = {}

        # Until we have command line arguments parsed, dump any stack traces
        self.dump_stack_trace = True

        # This is instantiated in initialize_app() only when using
        # password flow auth
        self.auth_client = None

        # Assume TLS host certificate verification is enabled
        self.verify = True

        self.client_manager = None

        # NOTE(dtroyer): This hack changes the help action that Cliff
        #                automatically adds to the parser so we can defer
        #                its execution until after the api-versioned commands
        #                have been loaded.  There doesn't seem to be a
        #                way to edit/remove anything from an existing parser.

        # Replace the cliff-added help.HelpAction to defer its execution
        self.DeferredHelpAction = None
        for a in self.parser._actions:
            if type(a) == help.HelpAction:
                # Found it, save and replace it
                self.DeferredHelpAction = a

                # These steps are argparse-implementation-dependent
                self.parser._actions.remove(a)
                if self.parser._option_string_actions['-h']:
                    del self.parser._option_string_actions['-h']
                if self.parser._option_string_actions['--help']:
                    del self.parser._option_string_actions['--help']

                # Make a new help option to just set a flag
                self.parser.add_argument(
                    '-h', '--help',
                    action='store_true',
                    dest='deferred_help',
                    default=False,
                    help="Show this help message and exit",
                )

    def configure_logging(self):
        """Configure logging for the app

        Cliff sets some defaults we don't want so re-work it a bit
        """

        if self.options.debug:
            # --debug forces verbose_level 3
            # Set this here so cliff.app.configure_logging() can work
            self.options.verbose_level = 3

        super(OpenStackShell, self).configure_logging()
        root_logger = logging.getLogger('')

        # Set logging to the requested level
        if self.options.verbose_level == 0:
            # --quiet
            root_logger.setLevel(logging.ERROR)
        elif self.options.verbose_level == 1:
            # This is the default case, no --debug, --verbose or --quiet
            root_logger.setLevel(logging.WARNING)
        elif self.options.verbose_level == 2:
            # One --verbose
            root_logger.setLevel(logging.INFO)
        elif self.options.verbose_level >= 3:
            # Two or more --verbose
            root_logger.setLevel(logging.DEBUG)

        # Requests logs some stuff at INFO that we don't want
        # unless we have DEBUG
        requests_log = logging.getLogger("requests")

        # Other modules we don't want DEBUG output for
        cliff_log = logging.getLogger('cliff')
        stevedore_log = logging.getLogger('stevedore')
        iso8601_log = logging.getLogger("iso8601")

        if self.options.debug:
            # --debug forces traceback
            self.dump_stack_trace = True
            requests_log.setLevel(logging.DEBUG)
            cliff_log.setLevel(logging.DEBUG)
        else:
            self.dump_stack_trace = False
            requests_log.setLevel(logging.ERROR)
            cliff_log.setLevel(logging.ERROR)

        stevedore_log.setLevel(logging.ERROR)
        iso8601_log.setLevel(logging.ERROR)

    def run(self, argv):
        try:
            return super(OpenStackShell, self).run(argv)
        except Exception as e:
            if not logging.getLogger('').handlers:
                logging.basicConfig()
            if self.dump_stack_trace:
                self.log.error(traceback.format_exc(e))
            else:
                self.log.error('Exception raised: ' + str(e))
            return 1

    def build_option_parser(self, description, version):
        parser = super(OpenStackShell, self).build_option_parser(
            description,
            version)

        # service token auth argument
        parser.add_argument(
            '--os-url',
            metavar='<url>',
            default=utils.env('OS_URL'),
            help='Defaults to env[OS_URL]')
        # Global arguments
        parser.add_argument(
            '--os-region-name',
            metavar='<auth-region-name>',
            default=utils.env('OS_REGION_NAME'),
            help='Authentication region name (Env: OS_REGION_NAME)')
        parser.add_argument(
            '--os-cacert',
            metavar='<ca-bundle-file>',
            default=utils.env('OS_CACERT'),
            help='CA certificate bundle file (Env: OS_CACERT)')
        verify_group = parser.add_mutually_exclusive_group()
        verify_group.add_argument(
            '--verify',
            action='store_true',
            help='Verify server certificate (default)',
        )
        verify_group.add_argument(
            '--insecure',
            action='store_true',
            help='Disable server certificate verification',
        )
        parser.add_argument(
            '--os-default-domain',
            metavar='<auth-domain>',
            default=utils.env(
                'OS_DEFAULT_DOMAIN',
                default=DEFAULT_DOMAIN),
            help='Default domain ID, default=' +
                 DEFAULT_DOMAIN +
                 ' (Env: OS_DEFAULT_DOMAIN)')
        parser.add_argument(
            '--timing',
            default=False,
            action='store_true',
            help="Print API call timing info",
        )

        return clientmanager.build_plugin_option_parser(parser)

    def initialize_app(self, argv):
        """Global app init bits:

        * set up API versions
        * validate authentication info
        * authenticate against Identity if requested
        """

        super(OpenStackShell, self).initialize_app(argv)

        # Save default domain
        self.default_domain = self.options.os_default_domain

        # Loop through extensions to get API versions
        for mod in clientmanager.PLUGIN_MODULES:
            version_opt = getattr(self.options, mod.API_VERSION_OPTION, None)
            if version_opt:
                api = mod.API_NAME
                self.api_version[api] = version_opt
                # Command groups deal only with major versions
                version = '.v' + version_opt.replace('.', '_').split('_')[0]
                cmd_group = 'openstack.' + api.replace('-', '_') + version
                self.command_manager.add_command_group(cmd_group)
                self.log.debug(
                    '%(name)s API version %(version)s, cmd group %(group)s',
                    {'name': api, 'version': version_opt, 'group': cmd_group}
                )

        # Commands that span multiple APIs
        self.command_manager.add_command_group(
            'openstack.common')

        # This is the naive extension implementation referred to in
        # blueprint 'client-extensions'
        # Extension modules can register their commands in an
        # 'openstack.extension' entry point group:
        # entry_points={
        #     'openstack.extension': [
        #         'list_repo=qaz.github.repo:ListRepo',
        #         'show_repo=qaz.github.repo:ShowRepo',
        #     ],
        # }
        self.command_manager.add_command_group(
            'openstack.extension')
        # call InitializeXxx() here
        # set up additional clients to stuff in to client_manager??

        # Handle deferred help and exit
        if self.options.deferred_help:
            self.DeferredHelpAction(self.parser, self.parser, None, None)

        # Set up common client session
        if self.options.os_cacert:
            self.verify = self.options.os_cacert
        else:
            self.verify = not self.options.insecure

        self.client_manager = clientmanager.ClientManager(
            cli_options=self.options,
            verify=self.verify,
            api_version=self.api_version,
            pw_func=prompt_for_password,
        )

    def prepare_to_run_command(self, cmd):
        """Set up auth and API versions"""
        self.log.info(
            'command: %s -> %s.%s',
            getattr(cmd, 'cmd_name', '<none>'),
            cmd.__class__.__module__,
            cmd.__class__.__name__,
        )
        if cmd.auth_required:
            try:
                # Trigger the Identity client to initialize
                self.client_manager.auth_ref
            except Exception:
                pass
        return

    def clean_up(self, cmd, result, err):
        self.log.debug('clean_up %s', cmd.__class__.__name__)

        if err:
            self.log.debug('got an error: %s', err)

        # Process collected timing data
        if self.options.timing:
            # Loop through extensions
            for mod in self.ext_modules:
                client = getattr(self.client_manager, mod.API_NAME)
                if hasattr(client, 'get_timings'):
                    self.timing_data.extend(client.get_timings())

            # Use the Timing pseudo-command to generate the output
            tcmd = timing.Timing(self, self.options)
            tparser = tcmd.get_parser('Timing')

            # If anything other than prettytable is specified, force csv
            format = 'table'
            # Check the formatter used in the actual command
            if hasattr(cmd, 'formatter') \
                    and cmd.formatter != cmd._formatter_plugins['table'].obj:
                format = 'csv'

            sys.stdout.write('\n')
            targs = tparser.parse_args(['-f', format])
            tcmd.run(targs)


def main(argv=sys.argv[1:]):
    return OpenStackShell().run(argv)

if __name__ == "__main__":
    sys.exit(main(sys.argv[1:]))