Limnoria/src/ircutils.py

#!/usr/bin/env python

###
# Copyright (c) 2002-2004, Jeremiah Fincher
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"""
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 supybot.fix as fix

import re
import string
import textwrap
from itertools import imap
from cStringIO import StringIO as sio

import supybot.utils as utils

def debug(s, *args):
    """Prints a debug string.  Most likely replaced by our logging debug."""
    print '***', s % args

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 s.translate(_lowertrans)

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

nickEqual = strEqual

_nickchars = r'_[]\`^{}|-'
nickRe = re.compile(r'^[A-Za-z%s][0-9A-Za-z%s]*$'
                    % (re.escape(_nickchars), re.escape(_nickchars)))

def isNick(s, strictRfc=True):
    """Returns True if s is a valid IRC nick."""
    if strictRfc:
        return bool(nickRe.match(s))
    else:
        return not isChannel(s) and not isUserHostmask(s)

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)

_patternCache = {}
def _hostmaskPatternEqual(pattern, hostmask):
    """Returns True if hostmask matches the hostmask pattern pattern."""
    try:
        return _patternCache[pattern](hostmask) is not None
    except KeyError:
        # We make our own regexps, rather than use fnmatch, because fnmatch's
        # case-insensitivity is not IRC's case-insensitity.
        fd = sio()
        for c in pattern:
            if c == '*':
                fd.write('.*')
            elif c == '?':
                fd.write('.')
            elif c in '[{':
                fd.write('[[{]')
            elif c in '}]':
                fd.write(r'[}\]]')
            elif c in '|\\':
                fd.write(r'[|\\]')
            elif c in '^~':
                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

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 utils.isIP(host):
        L = host.split('.')
        L[-1] = '*'
        return '*!*@' + '.'.join(L)
    elif utils.isIPV6(host):
        L = host.split(':')
        L[-1] = '*'
        return '*!*@' + ':'.join(L)
    else:
        if '.' in host:
            return '*!*@*%s' % host[host.find('.'):]
        else:
            return '*!*@'  + host

_plusRequireArguments = 'ovhblkqe'
_minusRequireArguments = 'ovhbkqe'
def separateModes(args):
    """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 args:
        return []
    modes = args[0]
    assert modes[0] in '+-', 'Invalid args: %r' % args
    args = list(args[1:])
    ret = []
    for c in modes:
        if c in '+-':
            last = c
        else:
            if last == '+':
                requireArguments = _plusRequireArguments
            else:
                requireArguments = _minusRequireArguments
            if c in requireArguments:
                arg = args.pop(0)
                try:
                    arg = int(arg)
                except ValueError:
                    pass
                ret.append((last + c, arg))
            else:
                ret.append((last + c, None))
    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\x02' % s

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

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

# Definition of mircColors dictionary moved below because it became an IrcDict.
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
    elif bg is None:
        fg = mircColors[str(fg)]
        return '\x03%s%s\x03' % (fg.zfill(2), s)
    elif fg is None:
        bg = mircColors[str(bg)]
        return '\x03,%s%s\x03' % (bg.zfill(2), s)
    else:
        fg = mircColors[str(fg)]
        bg = mircColors[str(bg)]
        # No need to zfill fg because the comma delimits.
        return '\x03%s,%s%s\x03' % (fg, bg.zfill(2), 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)

def stripBold(s):
    """Returns the string s, with bold removed."""
    return s.replace('\x02', '')

_stripColorRe = re.compile(r'\x03(?:\d{1,2},\d{1,2}|\d{1,2}|,\d{1,2}|)')
def stripColor(s):
    """Returns the string s, with color removed."""
    return _stripColorRe.sub('', s)

def stripReverse(s):
    """Returns the string s, with reverse-video removed."""
    return s.replace('\x16', '')

def stripUnderline(s):
    """Returns the string s, with underlining removed."""
    return s.replace('\x1f', '').replace('\x1F', '')

def stripFormatting(s):
    """Returns the string s, with all formatting removed."""
    # stripColor has to go first because of some strings, check the tests.
    s = stripColor(s)
    s = stripBold(s)
    s = stripReverse(s)
    s = stripUnderline(s)
    return s.replace('\x0f', '').replace('\x0F', '')

class FormatContext(object):
    def __init__(self):
        self.reset()

    def reset(self):
        self.fg = None
        self.bg = None
        self.bold = False
        self.reverse = False
        self.underline = False

    def start(self, s):
        """Given a string, starts all the formatters in this context."""
        if self.bold:
            s = '\x02' + s
        if self.reverse:
            s = '\x16' + s
        if self.underline:
            s = '\x1f' + s
        if self.fg is not None or self.bg is not None:
            s = mircColor(s, fg=self.fg, bg=self.bg)[:-1] # Remove \x03.
        return s

    def end(self, s):
        """Given a string, ends all the formatters in this context."""
        if self.bold or self.reverse or \
           self.fg or self.bg or self.underline:
            # Should we individually end formatters?
            s += '\x0f'
        return s
            
class FormatParser(object):
    def __init__(self, s):
        self.fd = sio(s)
        self.last = None

    def getChar(self):
        if self.last is not None:
            c = self.last
            self.last = None
            return c
        else:
            return self.fd.read(1)

    def ungetChar(self, c):
        self.last = c

    def parse(self):
        context = FormatContext()
        c = self.getChar()
        while c:
            if c == '\x02':
                context.bold = not context.bold
            elif c == '\x16':
                context.reverse = not context.reverse
            elif c == '\x1f':
                context.underline = not context.underline
            elif c == '\x0f':
                context.reset()
            elif c == '\x03':
                self.getColor(context)
            c = self.getChar()
        return context

    def getInt(self):
        i = 0
        setI = False
        c = self.getChar()
        while c.isdigit() and i < 100:
            setI = True
            i *= 10
            i += int(c)
            c = self.getChar()
        self.ungetChar(c)
        if setI:
            return i
        else:
            return None

    def getColor(self, context):
        context.fg = self.getInt()
        c = self.getChar()
        if c == ',':
            context.bg = self.getInt()

def wrap(s, length):
    if length < 100:
        raise ValueError, 'Use ircutils.wrap with a length greater than 100.'
    processed = []
    chunks = textwrap.wrap(s, length)
    context = None
    for chunk in chunks:
        if context is not None:
            chunk = context.start(chunk)
        context = FormatParser(chunk).parse()
        processed.append(context.end(chunk))
    return processed
        
def isValidArgument(s):
    """Returns whether 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

def safeArgument(s):
    """If s is unsafe for IRC, returns a safe version."""
    if isinstance(s, unicode):
        s = s.encode('utf-8')
    elif not isinstance(s, basestring):
        debug('Got a non-string in safeArgument: %r', s)
        s = str(s)
    if isValidArgument(s):
        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 utils.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 __new__(cls, s=''):
        x = super(IrcString, cls).__new__(cls, s)
        x.lowered = toLower(x)
        return x

    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(utils.InsensitivePreservingDict):
    """Subclass of dict to make key comparison IRC-case insensitive."""
    key = staticmethod(toLower)


class IrcSet(utils.NormalizingSet):
    """A sets.Set using IrcStrings instead of regular strings."""
    def normalize(self, s):
        return IrcString(s)
    
    def __reduce__(self):
        return (self.__class__, (list(self),))


mircColors = IrcDict({
    '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',
    'dark gray': '14',
    'light gray': '15',
})

# We'll map integers to their string form so mircColor is simpler.
for (k, v) in mircColors.items():
    if k is not None: # Ignore empty string for None.
        sv = str(v)
        mircColors[sv] = sv

if __name__ == '__main__':
    import sys, doctest
    doctest.testmod(sys.modules['__main__'])
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