#!/usr/bin/env python

# Copyright (c) 2002, 2003, 2004, 2005 Sebastian Stark
# Copyright (c) 2011, 2019-2021 Stefane Fermigier
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR SEBASTIAN STARK
# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR
# OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


"""Distributed command execution

Usage: tentakel [ options ] [ command ]
 -c file        Use file as config file
 -g group       Select group
 -l             Print list of available groups
 -h             Display this help text
 -v             Display version information
 command        Remote command. Interactive mode if not specified

See tentakel(1) for more information
"""

import getopt
import os
import sys
from pathlib import Path

from tentakel.error import Abort

try:
    from importlib import metadata
except ImportError:
    # Running on pre-3.8 Python; use importlib-metadata package
    import importlib_metadata as metadata  # type: ignore

from . import config, remote, shell


def main():
    group_name = "default"
    flag_listgroups = 0
    override_config = ""

    try:
        opts, args = getopt.getopt(sys.argv[1:], "g:hlvc:D")
    except getopt.GetoptError:
        print_help()
        raise Abort("parameter error")

    for o, v in opts:
        if o == "-h":
            print_help()
            sys.exit(0)
        if o == "-v":
            print(get_version())
            sys.exit(0)
        if o == "-D":
            print_info()
            sys.exit(0)

        if o == "-g":
            group_name = v
        if o == "-c":
            override_config = v
        if o == "-l":
            flag_listgroups = 1

    command = " ".join(args)

    # check wether the user has chosen a specific configuration file
    # on the command line
    config_file = None
    if override_config:
        if os.path.isfile(override_config):
            config_file = override_config
        else:
            raise Abort(f"no such file: '{override_config}'")
    else:
        # look for configuration files from default locations
        configs = [
            os.path.join(config.__user_dir, "tentakel.conf"),
            "/etc/tentakel.conf",
        ]
        for c in configs:
            if os.path.isfile(c):
                config_file = c
                break

    if config_file is None:
        raise Abort("no configuration file found")

    # load configuration
    conf = config.ConfigBase()
    conf.load(Path(config_file))

    # process -g parameter
    if flag_listgroups:
        print("available groups:")
        for g in conf.get_groups():
            sys.stdout.write(g + " ")
        print()
        sys.exit(0)

    # batch mode: execute command
    if command:
        collator = remote.RemoteCollator(conf, group_name)
        collator.exec_all(command)
        collator.display_all()
        collator.join_all()
    else:
        # interactive mode: open shell
        sh = shell.TentakelShell(conf, group_name)
        sh.cmdloop(intro="interactive mode")


def print_help():
    print(__doc__)


def print_info():
    print(f"path: {__file__}")
    print(f"version: {get_version()}")


def get_version():
    return metadata.version("tentakel")


if __name__ == "__main__":
    main()
