"""
Command-line interface to the Nominatim functions for import, update,
database administration and querying.
"""
import logging
import os
import sys
import argparse
from pathlib import Path

from .config import Configuration
from .tools.exec_utils import run_legacy_script, run_php_server
from .errors import UsageError
from . import clicmd
from .clicmd.args import NominatimArgs
from .tools import tiger_data

LOG = logging.getLogger()


class CommandlineParser:
    """ Wraps some of the common functions for parsing the command line
        and setting up subcommands.
    """
    def __init__(self, prog, description):
        self.parser = argparse.ArgumentParser(
            prog=prog,
            description=description,
            formatter_class=argparse.RawDescriptionHelpFormatter)

        self.subs = self.parser.add_subparsers(title='available commands',
                                               dest='subcommand')

        # Arguments added to every sub-command
        self.default_args = argparse.ArgumentParser(add_help=False)
        group = self.default_args.add_argument_group('Default arguments')
        group.add_argument('-h', '--help', action='help',
                           help='Show this help message and exit')
        group.add_argument('-q', '--quiet', action='store_const', const=0,
                           dest='verbose', default=1,
                           help='Print only error messages')
        group.add_argument('-v', '--verbose', action='count', default=1,
                           help='Increase verboseness of output')
        group.add_argument('--project-dir', metavar='DIR', default='.',
                           help='Base directory of the Nominatim installation (default:.)')
        group.add_argument('-j', '--threads', metavar='NUM', type=int,
                           help='Number of parallel threads to use')


    def add_subcommand(self, name, cmd):
        """ Add a subcommand to the parser. The subcommand must be a class
            with a function add_args() that adds the parameters for the
            subcommand and a run() function that executes the command.
        """
        parser = self.subs.add_parser(name, parents=[self.default_args],
                                      help=cmd.__doc__.split('\n', 1)[0],
                                      description=cmd.__doc__,
                                      formatter_class=argparse.RawDescriptionHelpFormatter,
                                      add_help=False)
        parser.set_defaults(command=cmd)
        cmd.add_args(parser)

    def run(self, **kwargs):
        """ Parse the command line arguments of the program and execute the
            appropriate subcommand.
        """
        args = NominatimArgs()
        self.parser.parse_args(args=kwargs.get('cli_args'), namespace=args)

        if args.subcommand is None:
            self.parser.print_help()
            return 1

        for arg in ('module_dir', 'osm2pgsql_path', 'phplib_dir', 'sqllib_dir',
                    'data_dir', 'config_dir', 'phpcgi_path'):
            setattr(args, arg, Path(kwargs[arg]))
        args.project_dir = Path(args.project_dir).resolve()

        if 'cli_args' not in kwargs:
            logging.basicConfig(stream=sys.stderr,
                                format='%(asctime)s: %(message)s',
                                datefmt='%Y-%m-%d %H:%M:%S',
                                level=max(4 - args.verbose, 1) * 10)

        args.config = Configuration(args.project_dir, args.config_dir,
                                    environ=kwargs.get('environ', os.environ))

        log = logging.getLogger()
        log.warning('Using project directory: %s', str(args.project_dir))

        try:
            return args.command.run(args)
        except UsageError as exception:
            if log.isEnabledFor(logging.DEBUG):
                raise # use Python's exception printing
            log.fatal('FATAL: %s', exception)

        # If we get here, then execution has failed in some way.
        return 1


##### Subcommand classes
#
# Each class needs to implement two functions: add_args() adds the CLI parameters
# for the subfunction, run() executes the subcommand.
#
# The class documentation doubles as the help text for the command. The
# first line is also used in the summary when calling the program without
# a subcommand.
#
# No need to document the functions each time.
# pylint: disable=C0111
# Using non-top-level imports to make pyosmium optional for replication only.
# pylint: disable=E0012,C0415
class UpdateAddData:
    """\
    Add additional data from a file or an online source.

    Data is only imported, not indexed. You need to call `nominatim-update index`
    to complete the process.
    """

    @staticmethod
    def add_args(parser):
        group_name = parser.add_argument_group('Source')
        group = group_name.add_mutually_exclusive_group(required=True)
        group.add_argument('--file', metavar='FILE',
                           help='Import data from an OSM file')
        group.add_argument('--diff', metavar='FILE',
                           help='Import data from an OSM diff file')
        group.add_argument('--node', metavar='ID', type=int,
                           help='Import a single node from the API')
        group.add_argument('--way', metavar='ID', type=int,
                           help='Import a single way from the API')
        group.add_argument('--relation', metavar='ID', type=int,
                           help='Import a single relation from the API')
        group.add_argument('--tiger-data', metavar='DIR',
                           help='Add housenumbers from the US TIGER census database.')
        group = parser.add_argument_group('Extra arguments')
        group.add_argument('--use-main-api', action='store_true',
                           help='Use OSM API instead of Overpass to download objects')

    @staticmethod
    def run(args):
        if args.tiger_data:
            return tiger_data.add_tiger_data(args.config.get_libpq_dsn(),
                                             args.tiger_data,
                                             args.threads or 1,
                                             args.config,
                                             args.sqllib_dir)

        params = ['update.php']
        if args.file:
            params.extend(('--import-file', args.file))
        elif args.diff:
            params.extend(('--import-diff', args.diff))
        elif args.node:
            params.extend(('--import-node', args.node))
        elif args.way:
            params.extend(('--import-way', args.way))
        elif args.relation:
            params.extend(('--import-relation', args.relation))
        if args.use_main_api:
            params.append('--use-main-api')
        return run_legacy_script(*params, nominatim_env=args)


class QueryExport:
    """\
    Export addresses as CSV file from the database.
    """

    @staticmethod
    def add_args(parser):
        group = parser.add_argument_group('Output arguments')
        group.add_argument('--output-type', default='street',
                           choices=('continent', 'country', 'state', 'county',
                                    'city', 'suburb', 'street', 'path'),
                           help='Type of places to output (default: street)')
        group.add_argument('--output-format',
                           default='street;suburb;city;county;state;country',
                           help=("Semicolon-separated list of address types "
                                 "(see --output-type). Multiple ranks can be "
                                 "merged into one column by simply using a "
                                 "comma-separated list."))
        group.add_argument('--output-all-postcodes', action='store_true',
                           help=("List all postcodes for address instead of "
                                 "just the most likely one"))
        group.add_argument('--language',
                           help=("Preferred language for output "
                                 "(use local name, if omitted)"))
        group = parser.add_argument_group('Filter arguments')
        group.add_argument('--restrict-to-country', metavar='COUNTRY_CODE',
                           help='Export only objects within country')
        group.add_argument('--restrict-to-osm-node', metavar='ID', type=int,
                           help='Export only children of this OSM node')
        group.add_argument('--restrict-to-osm-way', metavar='ID', type=int,
                           help='Export only children of this OSM way')
        group.add_argument('--restrict-to-osm-relation', metavar='ID', type=int,
                           help='Export only children of this OSM relation')


    @staticmethod
    def run(args):
        params = ['export.php',
                  '--output-type', args.output_type,
                  '--output-format', args.output_format]
        if args.output_all_postcodes:
            params.append('--output-all-postcodes')
        if args.language:
            params.extend(('--language', args.language))
        if args.restrict_to_country:
            params.extend(('--restrict-to-country', args.restrict_to_country))
        if args.restrict_to_osm_node:
            params.extend(('--restrict-to-osm-node', args.restrict_to_osm_node))
        if args.restrict_to_osm_way:
            params.extend(('--restrict-to-osm-way', args.restrict_to_osm_way))
        if args.restrict_to_osm_relation:
            params.extend(('--restrict-to-osm-relation', args.restrict_to_osm_relation))

        return run_legacy_script(*params, nominatim_env=args)


class AdminServe:
    """\
    Start a simple web server for serving the API.

    This command starts the built-in PHP webserver to serve the website
    from the current project directory. This webserver is only suitable
    for testing and develop. Do not use it in production setups!

    By the default, the webserver can be accessed at: http://127.0.0.1:8088
    """

    @staticmethod
    def add_args(parser):
        group = parser.add_argument_group('Server arguments')
        group.add_argument('--server', default='127.0.0.1:8088',
                           help='The address the server will listen to.')

    @staticmethod
    def run(args):
        run_php_server(args.server, args.project_dir / 'website')

def get_set_parser(**kwargs):
    """\
    Initializes the parser and adds various subcommands for
    nominatim cli.
    """
    parser = CommandlineParser('nominatim', nominatim.__doc__)

    parser.add_subcommand('import', clicmd.SetupAll)
    parser.add_subcommand('freeze', clicmd.SetupFreeze)
    parser.add_subcommand('replication', clicmd.UpdateReplication)

    parser.add_subcommand('special-phrases', clicmd.ImportSpecialPhrases)

    parser.add_subcommand('add-data', UpdateAddData)
    parser.add_subcommand('index', clicmd.UpdateIndex)
    parser.add_subcommand('refresh', clicmd.UpdateRefresh)

    parser.add_subcommand('admin', clicmd.AdminFuncs)

    parser.add_subcommand('export', QueryExport)
    parser.add_subcommand('serve', AdminServe)

    if kwargs.get('phpcgi_path'):
        parser.add_subcommand('search', clicmd.APISearch)
        parser.add_subcommand('reverse', clicmd.APIReverse)
        parser.add_subcommand('lookup', clicmd.APILookup)
        parser.add_subcommand('details', clicmd.APIDetails)
        parser.add_subcommand('status', clicmd.APIStatus)
    else:
        parser.parser.epilog = 'php-cgi not found. Query commands not available.'

    parser.add_subcommand('transition', clicmd.AdminTransition)

    return parser


def nominatim(**kwargs):
    """\
    Command-line tools for importing, updating, administrating and
    querying the Nominatim database.
    """
    parser = get_set_parser(**kwargs)

    return parser.run(**kwargs)
