Limnoria/src/ircutils.py

#!/usr/bin/env python

###
# Copyright (c) 2002, Jeremiah Fincher
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#   * Redistributions of source code must retain the above copyright notice,
#     this list of conditions, and the following disclaimer.
#   * 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.
#   * Neither the name of the author of this software nor the name of
#     contributors to this software may be used to endorse or promote products
#     derived from this software without specific prior written consent.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER 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.
###

"""
Provides a great number of useful utility functions IRC.  Things to muck around
with hostmasks, set bold or color on strings, IRC-case-insensitive dicts, a
nick class to handle nicks (so comparisons and hashing and whatnot work in an
IRC-case-insensitive fashion), and numerous other things.
"""

__revision__ = "$Id$"

import fix

import re
import copy
import sets
import time
import random
import socket
import string
import fnmatch
import operator
from itertools import imap
from cStringIO import StringIO as sio

def isUserHostmask(s):
    """Returns whether or not the string s is a valid User hostmask."""
    p1 = s.find('!')
    p2 = s.find('@')
    if p1 < p2-1 and p1 >= 1 and p2 >= 3 and len(s) > p2+1:
        return True
    else:
        return False

def isServerHostmask(s):
    """Returns True if s is a valid server hostmask."""
    return not isUserHostmask(s)

def nickFromHostmask(hostmask):
    """Returns the nick from a user hostmask."""
    assert isUserHostmask(hostmask)
    return hostmask.split('!', 1)[0]

def userFromHostmask(hostmask):
    """Returns the user from a user hostmask."""
    assert isUserHostmask(hostmask)
    return hostmask.split('!', 1)[1].split('@', 1)[0]

def hostFromHostmask(hostmask):
    """Returns the host from a user hostmask."""
    assert isUserHostmask(hostmask)
    return hostmask.split('@', 1)[1]

def splitHostmask(hostmask):
    """Returns the nick, user, host of a user hostmask."""
    assert isUserHostmask(hostmask)
    nick, rest = hostmask.split('!', 1)
    user, host = rest.split('@', 1)
    return (nick, user, host)

def joinHostmask(nick, ident, host):
    """Joins the nick, ident, host into a user hostmask."""
    assert nick and ident and host
    return '%s!%s@%s' % (nick, ident, host)

_lowertrans = string.maketrans(string.ascii_uppercase + r'\[]~',
                               string.ascii_lowercase + r'|{}^')
def toLower(s):
    """Returns the string s lowered according to IRC case rules."""
    return intern(s.translate(_lowertrans))

def nickEqual(nick1, nick2):
    """Returns True if nick1 == nick2 according to IRC case rules."""
    return toLower(nick1) == toLower(nick2)

_nickchars = r'_[]\`^{}|-'
nickRe = re.compile(r'^[A-Za-z%s][0-9A-Za-z%s]*$' % (re.escape(_nickchars),
                                                     re.escape(_nickchars)))
def isCtcp(msg):
    """Returns whether or not msg is a CTCP message."""
    return msg.command == 'PRIVMSG' and \
           msg.args[1].startswith('\x01') and \
           msg.args[1].endswith('\x01')

def isNick(s):
    """Returns True if s is a valid IRC nick."""
    if re.match(nickRe, s):
        return True
    else:
        return False

def isChannel(s):
    """Returns True if s is a valid IRC channel name."""
    return (s and s[0] in '#&+!' and len(s) <= 50 and \
            '\x07' not in s and ',' not in s and ' ' not in s)

_match = fnmatch.fnmatchcase

_patternCache = {}
def _hostmaskPatternEqual(pattern, hostmask):
    """Returns True if hostmask matches the hostmask pattern pattern."""
    try:
        return _patternCache[pattern](hostmask) is not None
    except KeyError:
        fd = sio()
        for c in pattern:
            if c == '*':
                fd.write('.*')
            elif c == '?':
                fd.write('.')
            elif c == '[' or c == '{':
                fd.write('[[{]')
            elif c == '}' or c == ']':
                fd.write(r'[}\]]')
            elif c == '|' or c == '\\':
                fd.write(r'[|\\]')
            elif c == '^' or c == '~':
                fd.write('[~^]')
            else:
                fd.write(re.escape(c))
        fd.write('$')
        f = re.compile(fd.getvalue(), re.I).match
        _patternCache[pattern] = f
        return f(hostmask) is not None

_hostmaskPatternEqualCache = {}
def hostmaskPatternEqual(pattern, hostmask):
    try:
        return _hostmaskPatternEqualCache[(pattern, hostmask)]
    except KeyError:
        b = _hostmaskPatternEqual(pattern, hostmask)
        _hostmaskPatternEqualCache[(pattern, hostmask)] = b
        return b

_ipchars = string.digits + '.'
def isIP(s):
    """Returns whether or not a given string is an IPV4 address.

    >>> isIP('255.255.255.255')
    1

    >>> isIP('abc.abc.abc.abc')
    0
    """
    try:
        return bool(socket.inet_aton(s))
    except socket.error:
        return False

def isIPV6(s):
    """Returns whether or not a given string is an IPV6 address."""
    try:
        return bool(socket.inet_pton(socket.AF_INET6, s))
    except socket.error:
        try:
            socket.inet_pton(socket.AF_INET6, '::')
        except socket.error:
            # We gotta fake it.
            if s.count('::') <= 1:
                L = s.split(':')
                if len(L) <= 8:
                    for x in L:
                        if x:
                            try:
                                int(x, 16)
                            except ValueError:
                                return False
                    return True
        return False

def banmask(hostmask):
    """Returns a properly generic banning hostmask for a hostmask.

    >>> banmask('nick!user@host.domain.tld')
    '*!*@*.domain.tld'

    >>> banmask('nick!user@10.0.0.1')
    '*!*@10.0.0.*'
    """
    assert isUserHostmask(hostmask)
    host = hostFromHostmask(hostmask)
    if isIP(host):
        L = host.split('.')
        L[-1] = '*'
        return '*!*@' + '.'.join(L)
    elif isIPV6(host):
        L = host.split(':')
        L[-1] = '*'
        return '*!*@' + ':'.join(L)
    else:
        if '.' in host:
            return '*!*@*%s' % host[host.find('.'):]
        else:
            return '*!*@'  + host

def separateModes(args, requireArguments='ovhblkqe'):
    """Separates modelines into single mode change tuples.  Basically, you
    should give it the .args of a MODE IrcMsg.

    Examples:

    >>> separateModes(['+ooo', 'jemfinch', 'StoneTable', 'philmes'])
    [('+o', 'jemfinch'), ('+o', 'StoneTable'), ('+o', 'philmes')]

    >>> separateModes(['+o-o', 'jemfinch', 'PeterB'])
    [('+o', 'jemfinch'), ('-o', 'PeterB')]

    >>> separateModes(['+s-o', 'test'])
    [('+s', None), ('-o', 'test')]

    >>> separateModes(['+sntl', '100'])
    [('+s', None), ('+n', None), ('+t', None), ('+l', '100')]
    """
    if not requireArguments:
        if not isinstance(args, list):
            args = [args]
    modes = args[0]
    assert modes[0] in '+-', 'Invalid args: %r' % args
    args = list(args[1:])
    ret = []
    index = 0
    length = len(modes)
    while index < length:
        if modes[index] in '+-':
            last = modes[index]
            index += 1
        else:
            if modes[index] in requireArguments:
                ret.append((last + modes[index], args.pop(0)))
            else:
                ret.append((last + modes[index], None))
            index += 1
    if not requireArguments: # Special case
        return [x for (x, y) in ret]
    else:
        return ret

def joinModes(modes):
    """Joins modes of the same form as returned by separateModes."""
    args = []
    modeChars = []
    currentMode = '\x00'
    for (mode, arg) in modes:
        if arg is not None:
            args.append(arg)
        if not mode.startswith(currentMode):
            currentMode = mode[0]
            modeChars.append(mode[0])
        modeChars.append(mode[1])
    args.insert(0, ''.join(modeChars))
    return args

def bold(s):
    """Returns the string s, bolded."""
    return '\x02%s\x0F' % s

def reverse(s):
    """Returns the string s, reverse-videoed."""
    return '\x16%s\x0F' % s

def underline(s):
    """Returns the string s, underlined."""
    return '\x1F%s\x0F' % s

mircColors = {
    None: '',
    'white': 0,
    'black': 1,
    'blue': 2,
    'green': 3,
    'red': 4,
    'brown': 5,
    'purple': 6,
    'orange': 7,
    'yellow': 8,
    'light green': 9,
    'teal': 10,
    'light blue': 11,
    'dark blue': 12,
    'pink': 13,
    'dark grey': 14,
    'light grey': 15,
}

# Offer a reverse mapping from integers to their associated colors.
for (k, v) in mircColors.items():
    if k is not None: # Ignore empty string for None.
        mircColors[v] = k

def mircColor(s, fg=None, bg=None):
    """Returns s with the appropriate mIRC color codes applied."""
    if fg is None and bg is None:
        return s
    if fg is None or isinstance(fg, str):
        fg = mircColors[fg]
    if bg is None:
        return '\x03%s%s\x0F' % (fg, s)
    else:
        if isinstance(bg, str):
            bg = mircColors[bg]
        return '\x03%s,%s%s\x0F' % (fg, bg, s)

def canonicalColor(s, bg=False, shift=0):
    """Assigns an (fg, bg) canonical color pair to a string based on its hash
    value.  This means it might change between Python versions.  This pair can
    be used as a *parameter to mircColor.  The shift parameter is how much to
    right-shift the hash value initially.
    """
    h = hash(s) >> shift
    fg = h % 14 + 2 # The + 2 is to rule out black and white.
    if bg:
        bg = (h >> 4) & 3 # The 5th, 6th, and 7th least significant bits.
        if fg < 8:
            bg += 8
        else:
            bg += 2
        return (fg, bg)
    else:
        return (fg, None)

_unColorRe = re.compile('(?:\x03\\d{1,2},\\d{1,2})|\x03\\d{1,2}|\x03|\x0F')
def unColor(s):
    """Removes the color from a string."""
    return _unColorRe.sub('', s)

def isValidArgument(s):
    """Returns if s is strictly a valid argument for an IRC message."""
    return '\r' not in s and '\n' not in s and '\x00' not in s

notFunky = string.ascii[32:]+'\x02\x03\x0F\x16\x1F'
def safeArgument(s):
    """If s is unsafe for IRC, returns a safe version."""
    assert not isinstance(s, unicode),'Unicode strings are not allowed in IRC.'
    if isValidArgument(s) and s.translate(string.ascii, notFunky) == '':
        return s
    else:
        return repr(s)

def replyTo(msg):
    """Returns the appropriate target to send responses to msg."""
    if isChannel(msg.args[0]):
        return msg.args[0]
    else:
        return msg.nick

def dccIP(ip):
    """Returns in IP in the proper for DCC."""
    assert isIP(ip), 'argument must be a string ip in xxx.yyy.zzz.www format.'
    i = 0
    x = 256**3
    for quad in ip.split('.'):
        i += int(quad)*x
        x /= 256
    return i

def unDccIP(i):
    """Takes an integer DCC IP and return a normal string IP."""
    assert isinstance(i, (int, long)), '%r is not an number.' % i
    L = []
    while len(L) < 4:
        L.append(i % 256)
        i /= 256
    L.reverse()
    return '.'.join(imap(str, L))

class IrcString(str):
    """This class does case-insensitive comparison and hashing of nicks."""
    def __init__(self, s):
        assert isinstance(s, basestring), \
               'Cannot make an IrcString from %s' % type(s)
        str.__init__(self, intern(s)) # This does nothing, I fear.
        self.lowered = toLower(s)

    def __eq__(self, s):
        try:
            return toLower(s) == self.lowered
        except:
            return False

    def __ne__(self, s):
        return not self == s

    def __hash__(self):
        return hash(self.lowered)


class IrcDict(dict):
    """Subclass of dict to make key comparison IRC-case insensitive."""
    def __init__(self, *args, **kwargs):
        self.__parent = super(IrcDict, self)
        self.__parent.__init__(*args, **kwargs)
        
    def __contains__(self, s):
        return self.__parent.__contains__(IrcString(s))
    has_key = __contains__

    def __setitem__(self, s, v):
        self.__parent.__setitem__(IrcString(s), v)

    def __getitem__(self, s):
        return self.__parent.__getitem__(IrcString(s))

    def __delitem__(self, s):
        self.__parent.__delitem__(IrcString(s))

    def __repr__(self):
        return '%s(%s)' % (self.__class__.__name__, self.__parent.__repr__())

    def __reduce__(self):
        return (self.__class__, (dict(self),))

class IrcSet(sets.Set):
    """A sets.Set using IrcStrings instead of regular strings."""
    def __init__(self, seq=()):
        self.__parent = super(IrcSet, self)
        self.__parent.__init__()
        for elt in seq:
            self.add(elt)
        
    def add(self, s):
        return self.__parent.add(IrcString(s))

    def remove(self, s):
        return self.__parent.remove(IrcString(s))

    def discard(self, s):
        return self.__parent.discard(IrcString(s))

    def __contains__(self, s):
        return self.__parent.__contains__(IrcString(s))
    has_key = __contains__

    def __reduce__(self):
        return (self.__class__, (list(self),))


if __name__ == '__main__':
    import sys, doctest
    doctest.testmod(sys.modules['__main__'])
# vim:set shiftwidth=4 tabstop=8 expandtab textwidth=78: