#! /usr/local/bin/python3
#
# this file:
#   http://user.it.uu.se/~embe8573/bot/sth.py
#   https://dataswamp.org/~incal/bot/sth.py

import argparse
import html.parser
import importlib
import os
import pathlib
import pickle
import random
import re
import socket
import ssl
import subprocess
import sys
import textwrap
import time

from numpy    import loadtxt
from os       import listdir
from os.path  import isfile, join
from pprint   import pformat
from textwrap import indent

sys.path.append('py/')
import hello_world

__email__      = 'moasenwood@zoho.eu'

__author__     = 'incal, michi'
__contact__    = 'irc.dataswamp.org #dataswamp, ' + __email__
__credits__    = ['demsh', 'hhvn', 'incal', 'james', 'josuah', 'katzeilla', 'Lucas', 'maxxe', 'michi', 'solene', 'vrl']
__maintainer__ = 'incal'
__version__    = time.strftime('%Y-%m-%d', time.gmtime(os.path.getmtime(pathlib.Path(__file__).absolute())))

cli = argparse.ArgumentParser(description='swamp thing (sth) IRC bot')
cli.add_argument('-c',  '--channel',        type=str, help='IRC channel',                 default='#swamp-thing')
cli.add_argument('-D',  '--debug',                    help='enable debug messages',                                   action='store_true')
cli.add_argument('-d',  '--dry',                      help="dry run, don't connect",                                  action='store_true')
cli.add_argument('-e',  '--encode',                   help='use SSL',                                                 action='store_true')
cli.add_argument('-lf', '--log-file',       type=str, help='log file')
cli.add_argument('-ll', '--log-level',      type=int, help='log level, high is more',     default=3)
cli.add_argument('-m',  '--track-messages',           help='track messages',                                          action='store_true')
cli.add_argument('-n',  '--nick',           type=str, help='bot nick',                    default='sth')
cli.add_argument('-p',  '--port',           type=int, help='IRC port',                    default=6697)
cli.add_argument('-s',  '--server',         type=str, help='IRC server (host)',           default='irc.freenode.net')
cli.add_argument('-v',  '--version',                  help='show version and exit',                                   action='store_true')
cli.add_argument('-vl', '--verbose-level',  type=int, help='verbose level, high is more', default=2)
opts = cli.parse_args()

help_cmd_all  = 'all'
help_cmd_list = 'list'
help_cmd      = ['help',
                        '[CMD | %s | %s]' % (help_cmd_all, help_cmd_list),
                        'print command syntax/CMD docstring/all help/a list of commands']

alias_cmd_n   = 'alias'
alias_cmd     = [alias_cmd_n, '[[ALIAS [FUN]] | rm ALIAS]', 'print alias(es); create an alias for a function; remove alias. \cmd to inhibit']

alice_cmd     = ['alice',          'NICK MSG',                   "don't try this"]
ascii_cmd     = ['ascii',          'ASCII [NAME]',               "list/show ASCII art"]
bem_cmd       = ['bem',            '[dot]',                      'print known users']
cred_cmd      = ['cred',           '',                           'print credits']
echo_cmd      = ['echo',           'STR',                        'have ' + opts.nick + ' say STR']
echos_cmd     = ['echos',          'DATA',                       'send DATA']
elem_cmd      = ['elem',           'CITY',                       'not a docstring']
hi_cmd        = ['hi',             '',                           'say hi to the bot']
hist_cmd      = ['hist',           '[TECH [, ...]]',             'look up TECH in computer history [print db URL]']
ip_cmd        = ['ip',             '',                           'print bot IP']
join_cmd      = ['join',           'CHANNEL',                    'have ' + opts.nick + ' join CHANNEL']
junior_cmd    = ['junior',         '[senior]',                   'ask this person for help']
kill_cmd      = ['kill',           '',                           'kill the bot']
leet_cmd      = ['leet',           '[rev] STR',                  'translate STR to/from h4x0r']
name_cmd      = ['name',           '',                           "print the bot's name"]
nick_cmd      = ['nick',           'NICK',                       'set bot NICK']
quiz_cmd      = ['quiz',           '',                           'print quiz URLs']
r_cmd         = ['r',              '',                           "execute the channel's previous bot command"]
rand_cmd      = ['rand',           '',                           'print a random number']
rules_cmd     = ['rules',          '',                           'print channel guidelines URL']
plonk_cmd     = ['plonk',           '',                           'print how to not annoy or be annoyed with the bot']
senior_cmd    = ['senior',         '[POS|NICK]',                 "print NICK's ancienty POS. put nick as n.ick"]
src_cmd       = ['src',            '',                           'print bot source URLs']
stats_cmd     = ['stats',          '',                           'print system info']
time_cmd      = ['time',           '[TZ]',                       'print time, set timezone TZ']
ver_cmd       = ['ver',            '',                           'print bot version']

cmds = [
    alias_cmd,
    alice_cmd,
    ascii_cmd,
    bem_cmd,
    cred_cmd,
    echo_cmd,
    echos_cmd,
    elem_cmd,
    help_cmd,
    hi_cmd,
    hist_cmd,
    ip_cmd,
    join_cmd,
    junior_cmd,
    kill_cmd,
    leet_cmd,
    name_cmd,
    nick_cmd,
    quiz_cmd,
    r_cmd,
    rand_cmd,
    rules_cmd,
    plonk_cmd,
    senior_cmd,
    src_cmd,
    stats_cmd,
    time_cmd,
    ver_cmd
]
cmds.sort()

class Bot:
    def __init__(self):
        self.channel         = opts.channel
        self.debug           = opts.debug
        self.dry             = opts.dry
        self.encode          = opts.encode
        self.log_file        = opts.log_file
        self.log_lvl         = opts.log_level
        self.nick            = opts.nick
        self.port            = opts.port
        self.server          = opts.server
        self.track_msgs      = opts.track_messages
        self.ver             = opts.version
        self.verb_lvl        = opts.verbose_level

        self.ghost_channel   = "#ghost"
        self.ghost_channel_2 = "#ghost-reporting"

        self.data_dir        = 'data/'
        self.ascii_dir       = 'data/ascii/'

        self.aliases         = []
        self.alias_db        = self.data_dir + alias_cmd_n + '.db'

        self.bot_cmd_pf      = ',' + self.nick
        self.bot_cmd_pf_alt  = self.bot_cmd_pf[0] * 2

        self.last_cmd        = {}

        self.rules_url       = 'https://dataswamp.org/channel_guidelines.txt'
        self.scripts_loc     = 'scripts/'
        self.timestamp       = '%Y-%m-%dT%H:%M:%S'

        self.users           = []
        self.users_file      = self.data_dir + 'users.txt'

        self.zsh             = '/usr/local/bin/zsh'

        if self.ver:
            print(__version__)
            quit()
        else:
            self.create_dirs()
            self.init_users()

    def file_lines(self, f):
        # https://www.w3resource.com/python-exercises/file/python-io-exercise-9.php
        with open(f) as f:
            for i, l in enumerate(f):
                pass
        return i + 1

    def ascii(self, ascii_name, channel):
        msg = ""
        if ascii_name == "":
            msg = " ".join(sorted(os.listdir(self.ascii_dir)))
        elif channel != self.ghost_channel:
            msg = "Use " + self.ghost_channel + " for this command."
        else:
            ascii_file = self.ascii_dir + ascii_name + ".txt"
            if os.path.isfile(ascii_file):
                with open(ascii_file, 'r') as fp:
                    lines = fp.readlines()
                    for l in lines:
                        self.send_privmsg(channel, l)
            else:
                msg = "ASCII file not found: " + ascii_file
        if msg != "":
            self.send_privmsg(channel, msg)

    def alias_dump(self):
        with open(self.alias_db, 'wb+') as file:
            file.write(pickle.dumps(self.aliases))

    def alias_load(self):
        try:
            with open(self.alias_db, 'rb') as file:
                self.aliases = pickle.load(file)
        except:
            self.error('error loading alias file' + self.alias_db)

    def alias_print_alias(self, alias, channel):
        if self.aliases:
            for [a, f] in self.aliases:
                if a == alias:
                    s = a + ' - ' + f
                    self.send_privmsg(channel, s)
                    return
            s = 'undefined alias: ' + alias
            self.send_privmsg(channel, s)

    def alias_print(self, channel):
        if channel != self.ghost_channel and channel != self.ghost_channel_2:
            s = '(see ' + self.ghost_channel + ' for output)'
            self.send_privmsg(channel, s)
            channel = self.ghost_channel
        self.aliases = sorted(self.aliases)
        if self.aliases:
            for [a, f] in self.aliases:
                s = a + ' - ' + f
                self.send_privmsg(channel, s)
                self.sleep()

    def alias_add(self, a, f):
        if a != alias_cmd_n:
            old = self.aliases
            ali = [a, f]
            if ali not in self.aliases:
                self.aliases = [ali] + old
                self.alias_dump()

    def alias_clear(self):
        self.aliases = []

    def alias_lookup(self, cmd):
        key    = ''
        keylen = len(key)
        cmdlen = len(cmd)
        for [a, f] in self.aliases:
            key    = a
            keylen = len(key)
            if cmd.find(key) == 0 and (cmdlen == keylen or cmd[keylen] == ' '):
                return cmd.replace(key, f, 1)
        return cmd

    def alias_rm(self, alias, channel):
        new = list(filter(lambda ai: ai[0] != alias, self.aliases))
        if new != self.aliases:
            self.aliases = new
            self.alias_dump()

    def make_printable(self, s):
        # https://stackoverflow.com/a/54451837
        NOPRINT_TRANS_TABLE = {
            i: None for i in range(0, sys.maxunicode + 1) if not chr(i).isprintable()
        }
        return s.translate(NOPRINT_TRANS_TABLE)

    def leet(self, s, rev=False):
        new = s
        reps  = [
                 ['a', '4'], ['A', '4'],
                 ['e', '3'], ['E', '3'],
                 ['l', '1'], ['L', '1'],
                 ['o', '0'], ['O', '0'],
                 ['s', '5'], ['S', '5'],
                 ['t', '7'], ['T', '7'],
                ]
        for lamer, leet in reps:
            if rev:
                new = new.replace(leet, lamer)
            else:
                new = new.replace(lamer, leet)
        return new

    def find_urls(self, s):
        # https://www.geeksforgeeks.org/python-check-url-string/
        url_re = r"(?i)\b((?:https?://|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z] {2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'\".,<>?«»“”‘’]))"
        urls   = re.findall(url_re, s)
        return [u[0] for u in urls]

    def url_title(self, url, channel):
        # https://dataswamp.org/~incal/bot/scripts/url2title
        url2title = self.scripts_loc + 'url2title'
        self.shell_cmd([self.zsh, url2title, url], channel)

    def create_dirs(self):
        if not os.path.exists(self.data_dir):
            os.mkdir(self.data_dir)
        if not os.path.exists(self.ascii_dir):
            os.mkdir(self.ascii_dir)

    def greet(self, nick, channel):
        greeting = '%s: welcome to %s <%s>' % (nick, channel, self.rules_url)
        self.send_privmsg(channel, greeting)

    def add_users(self, users, channel=''):
        usrs = [u.replace('@','') for u in users]
        if channel:
            for u in usrs:
                last_char = u[-1]
                look_for = u
                if last_char == '_' or last_char == '1':
                    look_for = u[:-1]
                if not look_for in self.users:
                    self.greet(u, channel)
        self.users += usrs
        self.users  = list(dict.fromkeys(self.users))
        self.users.sort(key=str.lower)
        self.save_users()

    def add_user(self, user, channel):
        self.add_users([user], channel)

    def init_users(self):
        if not os.path.exists(self.users_file):
            with open(self.users_file, 'w'): pass
        if os.path.getsize(self.users_file) > 0:
            user_arr = loadtxt(self.users_file, dtype=str, comments='#', delimiter='\n', unpack=False)
            self.add_users(user_arr.tolist())

    def save_users(self):
        f         = open(self.users_file, 'w')
        write_str = '\n'.join(str(u) for u in self.users)
        print(write_str, file=f)
        f.close()

    def shell_cmd(self, cmd, channel=''):
        res = ''
        try:
            res = subprocess.run(cmd, stdout=subprocess.PIPE)
        except FileNotFoundError as e:
            self.error('command \'' + cmd[0] + '\' not found', e, channel)
            return
        if res:
            out = res.stdout.decode('utf-8')
            out = html.parser.unescape(out)
            if out and out != '\x0A':
                if channel:
                    print('sending ' + out + ' to channel')
                    self.send_privmsg(channel, out)
                return out

    def send_privmsg(self, channel, msg):
        # https://tools.ietf.org/rfc/rfc1459.txt - sect. 2.3.1, item 2
        max_len = 256
        lines = []
        m = self.make_printable(msg)
        if len(msg) > max_len:
            lines = textwrap.wrap(msg, max_len, break_long_words=False)
            for l in lines:
                self.send('PRIVMSG ' + channel + ' :' + l)
                self.sleep()
        else:
            self.send('PRIVMSG ' + channel + ' :' + m)

    def make_full_docstring(self, data):
        ds = self.bot_cmd_pf + ' ' + data[0]
        if data[1]:
            ds += ' '   + data[1]
        if data[2]:
            ds += '   ' + data[2]
        return ds

    def help_cmd_f(self, cmd, help_cmd, nick, channel):
        help_msg   = ''
        search_key = cmd[len(help_cmd[0]) + 1:]
        if search_key:
            if search_key == help_cmd_all:
                ds = ''
                for c in cmds:
                    ds = self.make_full_docstring(c)
                    self.send_privmsg(nick, ds)
                    self.sleep()
            elif search_key == help_cmd_list:
                for c in cmds:
                    help_msg += c[0] + ' '
                help_msg += "(try '" + self.bot_cmd_pf + " help CMD')"
                help_msg += ' [%s commands]' % len(cmds)
            elif search_key == 'elem':
                elem     = self.scripts_loc + search_key
                help_msg = self.shell_cmd([self.zsh, elem, "help"])
            else:
                found = False
                for c in cmds:
                    if search_key == c[0]:
                        help_msg = self.make_full_docstring(c)
                        found = True
                        break
                if not found:
                    help_msg = 'no such command: ' + search_key
        else:
            help_msg = 'syntax: ' + self.bot_cmd_pf + ' CMD[; ...] (or just ' + self.bot_cmd_pf_alt + ' CMD) where CMD is: '
            for c in cmds:
                help_msg += c[0]
                if c[1]:
                    help_msg += ' ' + c[1]
                help_msg += ', '
            help_msg = help_msg[:-2]

        if help_msg:
            self.send_privmsg(channel, help_msg)

    def dot_str(self, s):
        new = ''
        if s:
            new = s[:1] + '.' + s[1:]
        return new

    def sleep(self, dur=0.025):
        time.sleep(dur)

    def bot_cmd(self, cmd, channel, nick):
        ip_shell_cmd = ['curl', '-s', 'icanhazip.com']

        cmd = cmd.strip()

        delim_char = ';'
        if cmd.find(delim_char) != -1:
            input_cmds = cmd.split(delim_char)
            for c in input_cmds:
                self.bot_cmd(c, channel, nick)
            return

        if cmd:
            if cmd[0] == '\\':
                cmd = cmd[1:]
            else:
                cmd = self.alias_lookup(cmd)
        else:
            return

        if cmd.find(nick_cmd[0]) == 0:
            nick = cmd[len(nick_cmd[0]) + 1:]
            if nick:
                self.nick_set(nick)

        elif cmd.find(alice_cmd[0]) == 0:
            start = len(alice_cmd[0]) + 1
            if len(cmd) >= start:
                args = cmd[start:]
                args_l = args.split()
                nick = args_l[0]
                msg = args[len(nick) + 1:]
                if msg != '':
                    self.send_privmsg(nick, msg)

        elif cmd.find(ascii_cmd[0]) == 0:
            ascii_name = cmd[len(ascii_cmd[0]) + 1:]
            if not ascii_name:
                ascii_name = ""
            self.ascii(ascii_name, channel)

        elif cmd.find(join_cmd[0]) == 0:
            cnl = cmd[len(join_cmd[0]) + 1:]
            if cnl:
                if cnl[0] != '#':
                    cnl = '#' + cnl
                self.join(cnl)

        # put this before echo
        elif cmd.find(echos_cmd[0]) == 0:
            send_cmd = cmd[len(echos_cmd[0]) + 1:]
            if send_cmd:
                self.send(send_cmd)

        elif cmd.find(echo_cmd[0]) == 0:
            say_what = cmd[len(echo_cmd[0]) + 1:]
            if say_what:
                self.send_privmsg(channel, say_what)

        elif cmd.find(alias_cmd[0]) == 0:
            args = cmd[len(alias_cmd[0]) + 1:]
            args_l = args.split()
            rm = alias_cmd[1][alias_cmd[1].find('|') + 2:]
            rm = rm[:rm.find(' ')]

            if args == '':
                self.alias_print(channel)
            elif args_l[0] == rm:
                for a in args_l[1:]:
                    self.alias_rm(a, channel)
            elif len(args_l) == 1:
                ali = args_l[0]
                self.alias_print_alias(ali, channel)
            elif len(args_l) >= 2:
                    ali   = args_l[0]
                    fun_l = args_l[1:]
                    fun   = ' '.join(fun_l)
                    self.alias_add(ali, fun)

        elif cmd.find(elem_cmd[0]) == 0:
            city = cmd[len(elem_cmd[0]) + 1:]
            if city:
                elem = self.scripts_loc + elem_cmd[0]
                res = self.shell_cmd([self.zsh, elem, city])
                if res:
                    self.send_privmsg(channel, res)

        elif cmd.find(senior_cmd[0]) == 0:
            arg = cmd[len(senior_cmd[0]) + 1:]
            senior = self.scripts_loc + senior_cmd[0]
            res = self.shell_cmd([self.zsh, senior, arg])
            if res:
                self.send_privmsg(channel, res)

        elif cmd == stats_cmd[0]:
            # https://dataswamp.org/~incal/bot/scripts/stats
            stats = self.scripts_loc + stats_cmd[0]
            res = self.shell_cmd([self.zsh, stats])
            if res:
                self.send_privmsg(channel, res)

        elif cmd.find(leet_cmd[0]) == 0:
            s = cmd[len(leet_cmd[0]) + 1:]
            out = ''
            rev_kwd = leet_cmd[1][leet_cmd[1].find('[') + 1 : leet_cmd[1].find(']')]
            if s.find(rev_kwd) == 0:
                s = s[len(rev_kwd) + 1:]
                out = self.leet(s, True)
            else:
                out = self.leet(s)
            self.send_privmsg(channel, out)

        elif cmd.find(bem_cmd[0]) == 0:
            style = cmd[len(bem_cmd[0]) + 1:]

            usrs  = []
            new   = ''
            if style == 'dot':
                for u in self.users:
                    new = self.dot_str(u)
                    usrs.append(new)
            else:
                for u in self.users:
                    new = self.leet(u)
                    if new == u:
                        new = self.dot_str(u)
                    usrs.append(new)

            usrs_str = ' '.join(sorted(usrs, key=str.lower))
            l = len(usrs)
            out = '%s (%s BEMs)' % (usrs_str, l)
            self.send_privmsg(channel, out)

        elif cmd == r_cmd[0]:
            cmd_last = self.last_cmd.get(channel)
            if cmd_last:
                self.bot_cmd(cmd_last, channel, nick)
            return

        elif cmd == cred_cmd[0]:
            cred = ' '.join(sorted(__credits__, key=str.lower))
            self.send_privmsg(nick, cred)

        elif cmd.find(help_cmd[0]) == 0:
            self.help_cmd_f(cmd, help_cmd, nick, channel)

        elif cmd.find(junior_cmd[0]) == 0:
            # https://dataswamp.org/~incal/bot/scripts/junior
            jnr = self.scripts_loc + junior_cmd[0]
            sen = cmd[len(junior_cmd[0]) + 1:]
            res = self.shell_cmd([self.zsh, jnr, sen])
            if res:
                self.send_privmsg(channel, res)

        elif cmd.find(hist_cmd[0]) == 0:
            # https://dataswamp.org/~incal/bot/scripts/hist
            tech = cmd[len(hist_cmd[0]) + 1:]

            techs = []
            if not tech:
                techs = 'db'
            else:
                techs = tech.split(',')

            for t in techs:
                ts   = t.strip()
                hist = self.scripts_loc + hist_cmd[0]
                res  = self.shell_cmd([self.zsh, hist, ts])
                if res:
                    self.send_privmsg(channel, res)
                else:
                    self.send_privmsg(channel, ts + ': no hit')

        elif cmd == hi_cmd[0] or cmd.find(hi_cmd[0] + ' ') == 0:
            end = ''
            rand = random.randint(0, 9)
            if rand == 0:
                end = ' :$'
            self.send_privmsg(channel, 'hi ' + nick + end)

        elif cmd == ip_cmd[0]:
            self.shell_cmd(ip_shell_cmd, channel)

        elif cmd == kill_cmd[0]:
            quit()

        elif cmd == name_cmd[0]:
            out = 'swamp thing <https://en.wikipedia.org/wiki/Swamp_Thing>'
            self.send_privmsg(channel, out)

        elif cmd == rand_cmd[0]:
            out = "%d" % random.randint(0, sys.maxsize)
            self.send_privmsg(channel, out)

        elif cmd == rules_cmd[0]:
            out = self.rules_url
            self.send_privmsg(channel, out)

        elif cmd == plonk_cmd[0]:
            plonk_msg = "Use #ghost to test and play with the bot. In catgirl, put 'ignore = sth' and 'ignore = * PRIVMSG * ,, *' in $XDG_CONFIG_HOME/catgirl or ~/.config/catgirl to block the bot including other people's use of it. In ERC, do (setq-default erc-ignore-list `(,@erc-ignore-list \"sth\"))"
            self.send_privmsg(channel, plonk_msg)

        elif cmd.find(src_cmd[0]) == 0:
            arg         = cmd[len(src_cmd[0]) + 1:]
            url         = 'https://dataswamp.org/~incal'
            dir_url     = url + '/bot/'
            scripts_url = dir_url + self.scripts_loc
            scripts     = [s for s in sorted(listdir(self.scripts_loc)) if isfile(join(self.scripts_loc, s))]
            if arg == '':
                bot_sec   = url + '/#bot'
                bot_src   = 'sth.py'
                bot_url   = dir_url + bot_src
                bot_lines = self.file_lines(bot_src)
                outp      = "%s %s [%d lines] " % (bot_sec, bot_url, bot_lines)

                outp += scripts_url + "SCRIPT where SCRIPT is "
                # https://stackoverflow.com/questions/3207219/how-do-i-list-all-files-of-a-directory
                total_lines = bot_lines
                lines       = 0
                for s in scripts:
                    sp           = self.scripts_loc + s
                    lines        = self.file_lines(sp)
                    total_lines += lines
                    outp        += "%s [%d] " % (s, lines)
                outp += "(total %d)" % total_lines
            elif arg in scripts:
                outp = scripts_url + arg
            else:
                outp = "no script: " + arg
            self.send_privmsg(channel, outp)

        elif cmd.find(time_cmd[0]) == 0:
            # https://stackoverflow.com/a/1398742
            tz_arg = cmd[len(time_cmd[0]) + 1:]
            now = time.time()
            if tz_arg:
                os.environ['TZ'] = tz_arg
                time.tzset()
            t = time.strftime('%Y-%m-%d %H:%M:%S %Z', time.localtime(now))
            self.send_privmsg(channel, t)

        elif cmd == ver_cmd[0]:
            self.send_privmsg(channel, __version__)

        elif cmd == quiz_cmd[0]:
            bike_quiz   = 'bikes: https://dataswamp.org/~incal/BIKE-QUIZ'
            cmp_quiz    = 'computers: https://dataswamp.org/~incal/CMP-QUIZ'
            interactive = 'interactive versions: http://nifty-networks.net:6969/'
            self.send_privmsg(channel, cmp_quiz)
            self.sleep()
            self.send_privmsg(channel, bike_quiz)
            self.sleep()
            self.send_privmsg(channel, interactive)

        else:
            cmd_file = 'py/' + cmd + '.py'
            if os.path.isfile(cmd_file):
                mod = __import__(cmd)
                importlib.reload(mod)
                out = mod.engage()
                self.send_privmsg(channel, out)
            else:
                self.send_privmsg(channel, "DNC")

        self.last_cmd[channel] = cmd

    def err(self, reason):
        self.output(reason, 0, 'err')
        exit

    def log(self, entry, msg_lvl=0):
        if self.log_file and msg_lvl <= self.log_lvl:
            entry = entry + '\n'
            f     = open(self.log_file, 'a')
            f.write(entry)
            f.close()

    def output(self, text, msg_lvl=2, from_where=''):
        # messages verbosity level:
        #   0 - error, the program terminates
        #   1 - warning
        #   2 - some info (default)
        #   3 - all info
        ts_prefix  = time.strftime(self.timestamp) + ' '
        err_prefix = 'ERR: '
        wrn_prefix = 'WRN: '

        prefix = ts_prefix
        if msg_lvl == 0:
            prefix += err_prefix
        elif msg_lvl == 1:
            prefix += wrn_prefix

        if self.track_msgs and from_where:
            prefix += ' [' + from_where + '] '

        out = prefix + text

        self.log(out, msg_lvl)

        if msg_lvl <= self.verb_lvl:
            print(out)

    def send(self, data):
        self.socket.send((data + '\r\n').encode())

    def error(self, desc, e='', channel=''):
        errstr = ''
        if e:
            errstr = "%s [exception %s]" % (desc, e.__class__.__name__)
        else:
            errstr = desc + " [failed]"
        if errstr and channel:
            self.send_privmsg(channel, errstr)
        elif errstr:
            print(errstr)

    def recv(self):
        bts = self.socket.recv(4096)
        if not bts :
            return -1
        try:
            decode = bts.decode()
        except UnicodeDecodeError as e:
            self.error("non-UTF-8 char(s)?", e)
            return
        lines = decode.splitlines()
        for l in lines:
            if l:
                self.output(l, from_where='recv')
                self.init_process(l)

    def connect(self, server, port, nick, encode):
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.connect((server, port))

        if encode:
            self.socket = ssl.wrap_socket(s)
        else:
            self.socket = s

        self.nick_set(nick)
        self.send('USER %s %s %s :%s' % (nick, nick, nick, nick))

    def nick_set(self, nick):
        self.nick = nick
        self.bot_cmd_pf = self.bot_cmd_pf[0] + self.nick
        self.send('NICK ' + self.nick)

    def join(self, channel):
        self.send('JOIN ' + channel)

    def names(self, channel):
        self.send('NAMES ' + channel)

    def mode(self, channel, nick, mode):
        self.send('MODE %s %s %s' % (channel, mode, nick))

    def voice(self, channel, nick):
        self.mode(channel, nick, '+v')

    def init_process(self, msg):
        here     = 'init_process'
        params   = []
        trailing = ''
        nick     = ''
        channel  = ''
        tkn      = msg.split()

        if len(tkn) < 2:
            self.output('msg too small', 3, here)
            return

        if tkn[0] and tkn[0][0] == ':':
            prefix = tkn.pop(0)[1:]
            if '!' in prefix:
                nick, idathost = re.split('!', prefix, 1)
            else:
                nick = prefix

        cmd = tkn.pop(0)

        while tkn:
            if tkn[0] and tkn[0][0] != ':':
                params.append(tkn.pop(0))
            else:
                tkn[0]   = tkn[0][1:]
                trailing = ' '.join(tkn)
                break

        # parse server cmd
        if cmd:
            self.output('cmd: ' + cmd, from_where=here)
        else:
            self.output('cannot tokenize', 1, here)

        if cmd == 'PING':
            daemon = trailing
            self.send('PONG ' + daemon)
            self.output('pong ' + daemon, from_where=here+'/PING')

        elif cmd == 'JOIN':
            if trailing:
                channel = trailing
            else:
                channel = params[0]
            if channel and nick:
                self.output(nick + ' joined ' + channel, from_where=here+'/JOIN')
                self.add_user(nick, channel)

        elif cmd == 'PART':
            channel = params[0]
            out     = nick + ' quit ' + channel
            self.output(out, from_where=here+'/PART')

        elif cmd == 'PRIVMSG':
            channel = params[0]
            usr_msg = trailing
            out     = nick + ' [' + channel + '] ' + usr_msg
            self.output(out, from_where=here+'/PRIVMSG')

            bot_cmd_hit = usr_msg.find(self.bot_cmd_pf)
            bot_cmd_alt_hit = usr_msg.find(self.bot_cmd_pf_alt)
            if bot_cmd_hit >= 0:
                cmd_index = bot_cmd_hit + len(self.bot_cmd_pf) + 1
                cmd_str   = usr_msg[cmd_index:]
                self.bot_cmd(cmd_str, channel, nick)
            elif bot_cmd_alt_hit >= 0:
                empty_cmd = False
                i = 2
                index = bot_cmd_alt_hit + 2
                if index <= len(usr_msg) - 1:
                    if usr_msg[index] == ' ':
                        i = 3
                else:
                    empty_cmd = True
                index = bot_cmd_alt_hit + i
                if index <= len(usr_msg) - 1:
                    cmd_str = usr_msg[bot_cmd_alt_hit + i:]
                    print(cmd_str)
                    self.bot_cmd(cmd_str, channel, nick)
                else:
                    empty_cmd = True
                if empty_cmd:
                    self.send_privmsg(channel, "empty barrels make the most noise")
            else:
                urls = self.find_urls(usr_msg)
                if urls:
                    urls = list(dict.fromkeys(urls))
                    for u in urls:
                        self.url_title(u, channel)

        elif cmd == '266':
            current   = params[1]
            max_users = params[2]
            out       = 'global users %s, max %s' % (current, max_users)
            self.output(out, from_where=here+'/266')

        elif cmd == '353':
            channel = params[2]
            users   = trailing.split()
            self.add_users(users, channel)

    def connect_and_join(self):
        online = False
        wait = 1
        while not online:
            try:
                self.connect(self.server, self.port, self.nick, self.encode)
                online = True
            except:
                err_string = "connect error. reconnecting in %ds" % wait
                self.error(err_string)
                wait *= 2
                self.sleep(wait)
        self.alias_load()
        self.join(self.channel)
        self.join(self.ghost_channel)
        self.join(self.ghost_channel_2)

    def main_loop(self):
        while True:
            if self.recv() == -1:
                self.error('receive error')
                self.connect_and_join()

bot = Bot()

if not bot.dry:
    bot.connect_and_join()
    bot.main_loop()