###
# Copyright (c) 2002-2004, Jeremiah Fincher
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# modification, are permitted provided that the following conditions are met:
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#   * Redistributions of source code must retain the above copyright notice,
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#     derived from this software without specific prior written consent.
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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, ilen
from cStringIO import StringIO as sio

import supybot.utils as utils
import supybot.structures as structures

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)

_rfc1459trans = string.maketrans(string.ascii_uppercase + r'\[]~',
                                 string.ascii_lowercase + r'|{}^')
def toLower(s, casemapping=None):
    """Returns the string s lowered according to IRC case rules."""
    if casemapping is None or casemapping == 'rfc1459':
        return s.translate(_rfc1459trans)
    elif casemapping == 'ascii': # freenode
        return s.lower()
    else:
        raise ValueError, 'Invalid casemapping: %r' % casemapping

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, nicklen=None):
    """Returns True if s is a valid IRC nick."""
    if strictRfc:
        ret = bool(nickRe.match(s))
        if ret and nicklen is not None:
            ret = len(s) <= nicklen
        return ret
    else:
        return not isChannel(s) and \
               not isUserHostmask(s) and \
               not ' ' in s and not '!' in s

def isChannel(s, chantypes='#&+!'):
    """Returns True if s is a valid IRC channel name."""
    return s and \
           len(s) <= 50 and \
            ',' not in s and \
            '\x07' not in s and \
            s[0] in chantypes and \
            len(s.split()) == 1

_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),))


class FloodQueue(object):
    timeout = 0
    def __init__(self, timeout=None, queues=None):
        if timeout is not None:
            self.timeout = timeout
        if queues is None:
            queues = IrcDict()
        self.queues = queues

    def __repr__(self):
        return 'FloodQueue(timeout=%r, queues=%s)' % (self.timeout,
                                                      repr(self.queues))

    def key(self, msg):
        return msg.user + '@' + msg.host

    def getTimeout(self):
        if callable(self.timeout):
            return self.timeout()
        else:
            return self.timeout

    def _getQueue(self, msg, insert=True):
        key = self.key(msg)
        try:
            return self.queues[key]
        except KeyError:
            if insert:
                # python--
                # instancemethod.__repr__ calls the instance.__repr__, which
                # means that our __repr__ calls self.queues.__repr__, which
                # calls structures.TimeoutQueue.__repr__, which calls
                # getTimeout.__repr__, which calls our __repr__, which calls...
                getTimeout = lambda : self.getTimeout()
                q = structures.TimeoutQueue(getTimeout)
                self.queues[key] = q
                return q
            else:
                return None
        
    def enqueue(self, msg, what=None):
        if what is None:
            what = msg
        q = self._getQueue(msg)
        q.enqueue(what)

    def len(self, msg):
        q = self._getQueue(msg, insert=False)
        if q is not None:
            return len(q)
        else:
            return 0

    def has(self, msg, what=None):
        q = self._getQueue(msg, insert=False)
        if q is not None:
            if what is None:
                what = msg
            for elt in q:
                if elt == what:
                    return True
        return False
            

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__'])
# vim:set shiftwidth=4 tabstop=8 expandtab textwidth=78: