#!/usr/bin/env python3

##
# This file is part of TALER
# (C) 2017 Taler Systems SA
#
# TALER is free software; you can redistribute it and/or
# modify it under the terms of the GNU Affero General Public
# License as published by the Free Software Foundation; either
# version 3, or (at your option) any later version.
#
# TALER is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty
# of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public
# License along with TALER; see the file COPYING.  If not,
# see <http://www.gnu.org/licenses/>
#
#  @author Florian Dold
#  @file CLI tool to manage all the bank's tasks.

import argparse
import django
import sys
import os
import os.path
import site
import logging
import inspect

import talerbank
from taler.util.talerconfig import TalerConfig
from django.core.management import call_command

SITE_PACKAGES = os.path.abspath(os.path.dirname(inspect.getfile(talerbank)) + "/..")

## Not commenting global variables, at least for now.
# @cond
LOGGER = logging.getLogger(__name__)

# No perfect match to our logging format, but good enough ...
UWSGI_LOGFMT = "%(ltime) %(proto) %(method) %(uri) %(proto) => %(status)"
## @endcond

##
# This function interprets the 'django' subcommand.
# This command usually manages database tasks, and in
# general what is not related to running the bank.
#
# @param args command line options.
def handle_django(args):
    django.setup()
    # always run 'migrate' first, in case a virgin db is being used.
    call_command('migrate')
    from django.core.management import execute_from_command_line
    execute_from_command_line([sys.argv[0] + " django"] + args.command)

##
# This function interprets the 'serve-http' subcommand.
# The effect it to launch the bank HTTP service.
#
# @param args command line options.
def handle_serve_http(args):
    import django
    django.setup()
    call_command('migrate')
    call_command('provide_accounts')
    call_command('check')
    port = args.port
    TC = TalerConfig.from_file(os.environ.get("TALER_CONFIG_FILE", args.config))
    if port is None:
        port = TC["bank"]["http_port"].value_int(required=True)

    httpspec = ":%d" % (port,)
    params = ["uwsgi", "uwsgi",
              "--static-map", "/static=%s/talerbank/app/static" % SITE_PACKAGES,
              "--master",
              "--die-on-term",
              "--http", httpspec,
              "--log-format", UWSGI_LOGFMT,
              "--module", "talerbank.wsgi"]
    os.execlp(*params)

##
# This function interprets the 'serve-uwsgi' subcommand.
# The effect is to launch the bank UWSGI service.  This
# type of service is usually used when the HTTP bank interface
# is accessed via a reverse proxy (like Nginx, for example).
#
# @param command line options.
def handle_serve_uwsgi(args):
    django.setup()
    call_command('migrate')
    call_command('provide_accounts')
    call_command('check')
    TC = TalerConfig.from_file(os.environ.get("TALER_CONFIG_FILE", args.config))
    serve_uwsgi = TC["bank"]["uwsgi_serve"].value_string(required=True).lower()
    params = ["uwsgi", "uwsgi",
              "--master",
              "--static-map", "/static=%s/talerbank/app/static" % SITE_PACKAGES,
              "--die-on-term",
              "--log-format", UWSGI_LOGFMT,
              "--module", "talerbank.wsgi"]
    if serve_uwsgi == "tcp":
        port = TC["bank"]["uwsgi_port"].value_int(required=True)
        spec = ":%d" % (port,)
        params.extend(["--socket", spec])
    else:
        spec = TC["bank"]["uwsgi_unixpath"].value_filename(required=True)
        mode = TC["bank"]["uwsgi_unixpath_mode"].value_filename(required=True)
        params.extend(["--socket", spec])
        params.extend(["--chmod-socket="+mode])
        os.makedirs(os.path.dirname(spec), exist_ok=True)
    logging.info("launching uwsgi with argv %s", params[1:])
    os.execlp(*params)

##
# Currently deprecated.
def handle_sampledata():
    django.setup()
    call_command('sample_donations')


##
# Interprets the '--config' option.
#
# @param args command line options.
def handle_config(args):
    TC = TalerConfig.from_file(os.environ.get("TALER_CONFIG_FILE", args.config))
    TC.from_file(args.config)
    TC.dump()


## Not commenting global variables, at least for now.
# @cond
PARSER = argparse.ArgumentParser()
PARSER.set_defaults(func=None)
PARSER.add_argument('--config', '-c', help="configuration file to use",
                    metavar="CONFIG", type=str, dest="config", default=None)
PARSER.add_argument('--with-db', type=str, metavar="dbtype:///dbname", dest="altdb",
                    help="use 'dbname' (currently only 'dbtype'=='postgres' is supported)")
SUB = PARSER.add_subparsers()

P = SUB.add_parser('django', help="Run django-admin command")
P.add_argument("command", nargs=argparse.REMAINDER)
P.set_defaults(func=handle_django)

P = SUB.add_parser('serve-http', help="Serve bank over HTTP")
P.add_argument("--port", "-p", dest="port", type=int,
               default=None, metavar="PORT")
P.set_defaults(func=handle_serve_http)

P = SUB.add_parser('serve-uwsgi', help="Serve bank over UWSGI")
P.set_defaults(func=handle_serve_uwsgi)

P = SUB.add_parser('config', help="show config")
P.set_defaults(func=handle_config)


ARGS = PARSER.parse_args()

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "talerbank.settings")

if ARGS.altdb:
    LOGGER.info("Setting alternate db: %s" % ARGS.altdb)
    os.environ.setdefault("TALER_BANK_ALTDB", ARGS.altdb)

if getattr(ARGS, 'func', None) is None:
    PARSER.print_help()
    sys.exit(1)

if ARGS.config is not None:
    os.environ["TALER_CONFIG_FILE"] = ARGS.config

try:
    ARGS.func(ARGS)
except django.db.utils.OperationalError as error:
    LOGGER.error(error)
    sys.exit(4)
## @endcond