#!/usr/bin/env python3
from argparse import ArgumentParser
from os import system
from os.path import basename
from random import shuffle
from sys import exit
from yaml import safe_load


GDEFAULTS = {
    'bots': {
        'level': 3,
        'names': ['anarki', 'angel', 'crash', 'doom', 'hunter',
                  'klesk', 'major', 'mynx', 'orbb', 'slash', 'xaero']
    }
}
MDEFAULTS = {
    'randomize': True,
    'vars': {
        'fraglimit': 30,
        'timelimit': 15
    }
}


def parse_arguments():
    desc = 'host a q3 server'
    parser = ArgumentParser(description=desc)
    parser.add_argument('-m', '--gamemode', default='default')
    parser.add_argument('-b', '--bots', type=int, default=0)
    parser.add_argument('-c', '--config', default='config.yml')
    parser.add_argument('-B', '--bootstrap')
    parser.add_argument('-d', '--debug', action="store_true")
    return parser.parse_args()


def gen_confline(param, value, archive=False):
    set_cmd = 'seta' if archive else 'set'
    return '{} {} "{}"\n'.format(set_cmd, param, value)


def gen_maplist(maplist, randomize=True):
    num = 1
    stmpl = 'set d{} "map {} ; set nextmap vstr d{}"\n'
    script = str()
    if randomize:
        shuffle(maplist)
    while maplist:
        nextnum = 1 if len(maplist) == 1 else num + 1
        script += stmpl.format(num, maplist.pop(), nextnum)
        num += 1
    script += 'vstr d1\n'
    return script


def gen_addbots(count, level, names):
    btmpl = 'addbot {} {}\n'
    script = str()
    shuffle(names)
    for bot in names[:count]:
        script += btmpl.format(bot, level)
    return script


def gen_exec(gcfg, mcfg, bvars=dict(), bot_count=0, debug=False):
    cfg_data = str()
    for param in bvars:
        cfg_data += gen_confline(param, bvars[param], archive=True)
    cfg_data += gen_maplist(mcfg['maps'],
                            mcfg.get('randomize', MDEFAULTS['randomize']))
    if bot_count:
        bot_level = gcfg.\
            get('bots', GDEFAULTS['bots']).\
            get('level', GDEFAULTS['bots']['level'])
        bot_names = gcfg.\
            get('bots', GDEFAULTS['bots']).\
            get('names', GDEFAULTS['bots']['names'])
        cfg_data += gen_addbots(bot_count, bot_level, bot_names)
    if debug:
        print('Debug {} contents:\n{}'.format(gcfg['exec'], cfg_data))
        return
    try:
        with open(gcfg['exec'], 'w+') as config:
            config.write(cfg_data)
    except FileNotFoundError as error:
        exit('Config `{}` not found!'.format(error.filename))


def main():
    args = parse_arguments()
    cfg_data, cmd_list, bvars = str(), list(), dict()
    try:
        with open(args.config, 'r') as config_file:
            gcfg = safe_load(config_file)
        assert {'user', 'exec', 'cmd'} <= gcfg.keys()
        mcfg = gcfg['gamemodes'][args.gamemode]
        assert 'maps' in mcfg
        if args.bootstrap:
            with open(args.bootstrap, 'r') as bootstrap_file:
                bvars = safe_load(bootstrap_file)
    except FileNotFoundError as error:
        exit('Config `{}` not found!'.format(error.filename))
    except (AssertionError, KeyError):
        exit('Missing required settings in {}!'.format(args.config))

    svars = mcfg.get('vars', MDEFAULTS['vars'])
    exec_filename = basename(gcfg['exec'])

    for param in svars:
        cmd_list.append('+set {} {}'.format(param, svars[param]))
    cmd_list.append('+exec {}'.format(exec_filename))
    cmd_opts = ' '.join(cmd_list)

    action = print if args.debug else system
    gen_exec(gcfg, mcfg, bvars, args.bots, args.debug)
    action('sudo -u {} {} {}'.format(gcfg['user'], gcfg['cmd'], cmd_opts))


if __name__ == '__main__':
    main()