import os
import sys
import pathlib
import json
import asyncio
import argparse
import logging
import logging.handlers
from docopt import docopt

import aiohttp
from aiohttp.web import GracefulExit

from lbrynet import __name__ as lbrynet_name, __version__ as lbrynet_version
from lbrynet.extras.daemon.loggly_handler import get_loggly_handler
from lbrynet.conf import Config, CLIConfig
from lbrynet.extras.daemon.Daemon import Daemon

log = logging.getLogger(lbrynet_name)
log.addHandler(logging.NullHandler())


def display(data):
    print(json.dumps(data, indent=2))


async def execute_command(conf, method, params):
    async with aiohttp.ClientSession() as session:
        try:
            message = {'method': method, 'params': params}
            async with session.get(conf.api_connection_url, json=message) as resp:
                try:
                    data = await resp.json()
                    if 'result' in data:
                        display(data['result'])
                    elif 'error' in data:
                        if 'message' in data['error']:
                            display(data['error']['message'])
                        else:
                            display(data['error'])
                except Exception as e:
                    log.exception('Could not process response from server:', exc_info=e)
        except aiohttp.ClientConnectionError:
            print("Could not connect to daemon. Are you sure it's running?")


def normalize_value(x, key=None):
    if not isinstance(x, str):
        return x
    if key in ('uri', 'channel_name', 'name', 'file_name', 'download_directory'):
        return x
    if x.lower() == 'true':
        return True
    if x.lower() == 'false':
        return False
    if x.isdigit():
        return int(x)
    return x


def remove_brackets(key):
    if key.startswith("<") and key.endswith(">"):
        return str(key[1:-1])
    return key


def set_kwargs(parsed_args):
    kwargs = {}
    for key, arg in parsed_args.items():
        k = None
        if arg is None:
            continue
        elif key.startswith("--") and remove_brackets(key[2:]) not in kwargs:
            k = remove_brackets(key[2:])
        elif remove_brackets(key) not in kwargs:
            k = remove_brackets(key)
        kwargs[k] = normalize_value(arg, k)
    return kwargs


def split_subparser_argument(parent, original, name, condition):
    new_sub_parser = argparse._SubParsersAction(
        original.option_strings,
        original._prog_prefix,
        original._parser_class,
        metavar=original.metavar
    )
    new_sub_parser._name_parser_map = original._name_parser_map
    new_sub_parser._choices_actions = [
        a for a in original._choices_actions if condition(original._name_parser_map[a.dest])
    ]
    group = argparse._ArgumentGroup(parent, name)
    group._group_actions = [new_sub_parser]
    return group


class ArgumentParser(argparse.ArgumentParser):
    def __init__(self, *args, group_name=None, **kwargs):
        super().__init__(*args, formatter_class=HelpFormatter, add_help=False, **kwargs)
        self.add_argument(
            '--help', dest='help', action='store_true', default=False,
            help='Show this help message and exit.'
        )
        self._optionals.title = 'Options'
        if group_name is None:
            self.epilog = (
                f"Run 'lbrynet COMMAND --help' for more information on a command or group."
            )
        else:
            self.epilog = (
                f"Run 'lbrynet {group_name} COMMAND --help' for more information on a command."
            )
            self.set_defaults(group=group_name, group_parser=self)

    def format_help(self):
        formatter = self._get_formatter()
        formatter.add_usage(
            self.usage, self._actions, self._mutually_exclusive_groups
        )
        formatter.add_text(self.description)

        # positionals, optionals and user-defined groups
        for action_group in self._granular_action_groups:
            formatter.start_section(action_group.title)
            formatter.add_text(action_group.description)
            formatter.add_arguments(action_group._group_actions)
            formatter.end_section()

        formatter.add_text(self.epilog)
        return formatter.format_help()

    @property
    def _granular_action_groups(self):
        if self.prog != 'lbrynet':
            yield from self._action_groups
            return
        yield self._optionals
        action: argparse._SubParsersAction = self._positionals._group_actions[0]
        yield split_subparser_argument(
            self, action, "Grouped Commands", lambda parser: 'group' in parser._defaults
        )
        yield split_subparser_argument(
            self, action, "Commands", lambda parser: 'group' not in parser._defaults
        )

    def error(self, message):
        self.print_help(argparse._sys.stderr)
        self.exit(2, '\n'+message+'\n')


class HelpFormatter(argparse.HelpFormatter):

    def add_usage(self, usage, actions, groups, prefix='Usage:  '):
        super().add_usage(
            usage, [a for a in actions if a.option_strings != ['--help']], groups, prefix
        )


def add_command_parser(parent, command):
    subcommand = parent.add_parser(
        command['name'],
        help=command['doc'].strip().splitlines()[0]
    )
    subcommand.set_defaults(
        api_method_name=command['api_method_name'],
        command=command['name'],
        doc=command['doc'],
        replaced_by=command.get('replaced_by', None)
    )


def get_argument_parser():
    main = ArgumentParser(
        'lbrynet', description='An interface to the LBRY Network.'
    )
    main.add_argument(
        '-v', '--version', dest='cli_version', action="store_true",
        help='Show lbrynet CLI version and exit.'
    )
    main.set_defaults(group=None, command=None)
    CLIConfig.contribute_to_argparse(main)
    sub = main.add_subparsers(metavar='COMMAND')
    start = sub.add_parser(
        'start',
        usage='lbrynet start [--config FILE] [--data-dir DIR] [--wallet-dir DIR] [--download-dir DIR] ...',
        help='Start LBRY Network interface.'
    )
    start.add_argument(
        '--quiet', dest='quiet', action="store_true",
        help='Disable all console output.'
    )
    start.add_argument(
        '--verbose', nargs="*",
        help=('Enable debug output. Optionally specify loggers for which debug output '
              'should selectively be applied.')
    )
    start.set_defaults(command='start', start_parser=start)
    Config.contribute_to_argparse(start)

    api = Daemon.get_api_definitions()
    groups = {}
    for group_name in sorted(api['groups']):
        group_parser = sub.add_parser(group_name, group_name=group_name, help=api['groups'][group_name])
        groups[group_name] = group_parser.add_subparsers(metavar='COMMAND')

    nicer_order = ['stop', 'get', 'publish', 'resolve']
    for command_name in sorted(api['commands']):
        if command_name not in nicer_order:
            nicer_order.append(command_name)

    for command_name in nicer_order:
        command = api['commands'][command_name]
        if command['group'] is None:
            add_command_parser(sub, command)
        else:
            add_command_parser(groups[command['group']], command)

    return main


def ensure_directory_exists(path: str):
    if not os.path.isdir(path):
        pathlib.Path(path).mkdir(parents=True, exist_ok=True)


def main(argv=None):
    argv = argv or sys.argv[1:]
    parser = get_argument_parser()
    args, command_args = parser.parse_known_args(argv)

    conf = Config.create_from_arguments(args)
    for directory in (conf.data_dir, conf.download_dir, conf.wallet_dir):
        ensure_directory_exists(directory)

    if args.cli_version:
        print(f"{lbrynet_name} {lbrynet_version}")
        return 0

    elif args.command == 'start':

        if args.help:
            args.start_parser.print_help()
            return 0
        default_formatter = logging.Formatter("%(asctime)s %(levelname)-8s %(name)s:%(lineno)d: %(message)s")
        file_handler = logging.handlers.RotatingFileHandler(
            conf.log_file_path, maxBytes=2097152, backupCount=5
        )
        file_handler.setFormatter(default_formatter)
        log.addHandler(file_handler)

        if not args.quiet:
            handler = logging.StreamHandler()
            handler.setFormatter(default_formatter)
            log.addHandler(handler)
            logging.getLogger('torba').addHandler(handler)
            logging.getLogger('torba').setLevel(logging.INFO)

        logging.getLogger('aioupnp').setLevel(logging.WARNING)
        logging.getLogger('aiohttp').setLevel(logging.CRITICAL)

        if args.verbose:
            log.setLevel(logging.DEBUG)
        else:
            log.setLevel(logging.INFO)
        if conf.share_usage_data:
            loggly_handler = get_loggly_handler()
            loggly_handler.setLevel(logging.ERROR)
            log.addHandler(loggly_handler)

        daemon = Daemon(conf)
        loop = asyncio.get_event_loop()
        try:
            loop.run_until_complete(daemon.start())
            loop.run_forever()
        except (GracefulExit, KeyboardInterrupt):
            pass
        finally:
            loop.run_until_complete(daemon.stop())
        if hasattr(loop, 'shutdown_asyncgens'):
            loop.run_until_complete(loop.shutdown_asyncgens())

    elif args.command is not None:

        doc = args.doc
        api_method_name = args.api_method_name
        if args.replaced_by:
            print(f"{args.api_method_name} is deprecated, using {args.replaced_by['api_method_name']}.")
            doc = args.replaced_by['doc']
            api_method_name = args.replaced_by['api_method_name']

        if args.help:
            print(doc)
        else:
            parsed = docopt(doc, command_args)
            params = set_kwargs(parsed)
            loop = asyncio.get_event_loop()
            loop.run_until_complete(execute_command(conf, api_method_name, params))

    elif args.group is not None:
        args.group_parser.print_help()

    else:
        parser.print_help()

    return 0


if __name__ == "__main__":
    sys.exit(main())