###
# Copyright (c) 2002-2004, Jeremiah Fincher
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# modification, are permitted provided that the following conditions are met:
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###

import re

import supybot.conf as conf
import supybot.utils as utils
from supybot.commands import *
import supybot.ircutils as ircutils
import supybot.registry as registry
import supybot.callbacks as callbacks

# Copied from the old privmsgs.py.
def getChannel(msg, args=()):
    """Returns the channel the msg came over or the channel given in args.

    If the channel was given in args, args is modified (the channel is
    removed).
    """
    if args and ircutils.isChannel(args[0]):
        if conf.supybot.reply.requireChannelCommandsToBeSentInChannel():
            if args[0] != msg.args[0]:
                s = 'Channel commands must be sent in the channel to which ' \
                    'they apply; if this is not the behavior you desire, ' \
                    'ask the bot\'s administrator to change the registry ' \
                    'variable ' \
                    'supybot.reply.requireChannelCommandsToBeSentInChannel ' \
                    'to False.'
                raise callbacks.Error, s
        return args.pop(0)
    elif ircutils.isChannel(msg.args[0]):
        return msg.args[0]
    else:
        raise callbacks.Error, 'Command must be sent in a channel or ' \
                               'include a channel in its arguments.'

def getArgs(args, required=1, optional=0):
    if len(args) < required:
        raise callbacks.ArgumentError
    if len(args) < required + optional:
        ret = list(args) + ([''] * (required + optional - len(args)))
    elif len(args) >= required + optional:
        ret = list(args[:required + optional - 1])
        ret.append(' '.join(args[required + optional - 1:]))
    if len(ret) == 1:
        return ret[0]
    else:
        return ret

class AliasError(Exception):
    pass

class RecursiveAlias(AliasError):
    pass

def findAliasCommand(s, alias):
    s = re.escape(s)
    r = re.compile(r'(?:(^|\[)\s*\b%s\b|\|\s*\b%s\b)' % (s, s))
    return bool(r.search(alias))

dollarRe = re.compile(r'\$(\d+)')
def findBiggestDollar(alias):
    dollars = dollarRe.findall(alias)
    dollars = map(int, dollars)
    dollars.sort()
    if dollars:
        return dollars[-1]
    else:
        return 0

atRe = re.compile(r'@(\d+)')
def findBiggestAt(alias):
    ats = atRe.findall(alias)
    ats = map(int, ats)
    ats.sort()
    if ats:
        return ats[-1]
    else:
        return 0

def makeNewAlias(name, alias):
    original = alias
    if findAliasCommand(name, alias):
        raise RecursiveAlias
    biggestDollar = findBiggestDollar(original)
    biggestAt = findBiggestAt(original)
    wildcard = '$*' in original
    if biggestAt and wildcard:
        raise AliasError, 'Can\'t mix $* and optional args (@1, etc.)'
    if original.count('$*') > 1:
        raise AliasError, 'There can be only one $* in an alias.'
    testTokens = callbacks.tokenize(original)
    if testTokens and isinstance(testTokens[0], list):
        raise AliasError, 'Commands may not be the result of nesting.'
    def f(self, irc, msg, args):
        alias = original.replace('$nick', msg.nick)
        if '$channel' in original:
            channel = getChannel(msg, args)
            alias = alias.replace('$channel', channel)
        tokens = callbacks.tokenize(alias)
        if not wildcard and biggestDollar or biggestAt:
            args = getArgs(args, required=biggestDollar, optional=biggestAt)
            # Gotta have a mutable sequence (for replace).
            if biggestDollar + biggestAt == 1: # We got a string, no tuple.
                args = [args]
        def regexpReplace(m):
            idx = int(m.group(1))
            return args[idx-1]
        def replace(tokens, replacer):
            for (i, token) in enumerate(tokens):
                if isinstance(token, list):
                    replace(token, replacer)
                else:
                    tokens[i] = replacer(token)
        replace(tokens, lambda s: dollarRe.sub(regexpReplace, s))
        if biggestAt:
            assert not wildcard
            args = args[biggestDollar:]
            replace(tokens, lambda s: atRe.sub(regexpReplace, s))
        if wildcard:
            assert not biggestAt
            # Gotta remove the things that have already been subbed in.
            i = biggestDollar
            while i:
                args.pop(0)
                i -= 1
            def everythingReplace(tokens):
                for (i, token) in enumerate(tokens):
                    if isinstance(token, list):
                        if everythingReplace(token):
                            return
                    if token == '$*':
                        tokens[i:i+1] = args
                        return True
                    elif '$*' in token:
                        tokens[i] = token.replace('$*', ' '.join(args))
                        return True
                return False
            everythingReplace(tokens)
        self.Proxy(irc, msg, tokens)
    doc =format('<an alias, %n>\n\nAlias for %q.',
                (biggestDollar, 'argument'), alias)
    f = utils.changeFunctionName(f, name, doc)
    return f

class Alias(callbacks.Privmsg):
    def __init__(self, irc):
        self.__parent = super(Alias, self)
        self.__parent.__init__(irc)
        # Schema: {alias: [command, locked]}
        self.aliases = {}
        # XXX This should go.  aliases should be a space separate list, etc.
        group = conf.supybot.plugins.Alias.aliases
        for (name, alias) in registry._cache.iteritems():
            name = name.lower()
            if name.startswith('supybot.plugins.alias.aliases.'):
                name = name[len('supybot.plugins.alias.aliases.'):]
                if '.' in name:
                    continue
                conf.registerGlobalValue(group, name, registry.String('', ''))
                conf.registerGlobalValue(group.get(name), 'locked',
                                         registry.Boolean(False, ''))
        for (name, value) in group.getValues(fullNames=False):
            name = name.lower() # Just in case.
            command = value()
            locked = value.locked()
            self.aliases[name] = [command, locked]
        for (alias, (command, locked)) in self.aliases.items():
            try:
                self.addAlias(irc, alias, command, locked)
            except Exception, e:
                self.log.exception('Exception when trying to add alias %s.  '
                                   'Removing from the Alias database.', alias)
                del self.aliases[alias]

    def lock(self, irc, msg, args, name):
        """<alias>

        Locks an alias so that no one else can change it.
        """
        if hasattr(self, name) and self.isCommand(name):
            self.aliases[name][1] = True
            conf.supybot.plugins.Alias.aliases.get(name).locked.setValue(True)
            irc.replySuccess()
        else:
            irc.error('There is no such alias.')
    lock = wrap(lock, [('checkCapability', 'admin'), 'commandName'])

    def unlock(self, irc, msg, args, name):
        """<alias>

        Unlocks an alias so that people can define new aliases over it.
        """
        if hasattr(self, name) and self.isCommand(name):
            self.aliases[name][1] = False
            conf.supybot.plugins.Alias.aliases.get(name).locked.setValue(False)
            irc.replySuccess()
        else:
            irc.error('There is no such alias.')
    unlock = wrap(unlock, [('checkCapability', 'admin'), 'commandName'])

    _invalidCharsRe = re.compile(r'[\[\]\s]')
    def addAlias(self, irc, name, alias, lock=False):
        if self._invalidCharsRe.search(name):
            raise AliasError, 'Names cannot contain spaces or square brackets.'
        if '|' in name:
            raise AliasError, 'Names cannot contain pipes.'
        if irc.getCallback(name):
            raise AliasError, 'Names cannot coincide with names of plugins.'
        realName = callbacks.canonicalName(name)
        if name != realName:
            s = format('That name isn\'t valid.  Try %q instead.', realName)
            raise AliasError, s
        name = realName
        cbs = callbacks.findCallbackForCommand(irc, name)
        if self in cbs:
            if hasattr(self, realName) and realName not in self.aliases:
                s = 'You can\'t overwrite commands in this plugin.'
                raise AliasError, s
        if name in self.aliases:
            (currentAlias, locked) = self.aliases[name]
            if locked and currentAlias != alias:
                raise AliasError, format('Alias %q is locked.', name)
        try:
            f = makeNewAlias(name, alias)
        except RecursiveAlias:
            raise AliasError, 'You can\'t define a recursive alias.'
        if name in self.aliases:
            # We gotta remove it so its value gets updated.
            conf.supybot.plugins.Alias.aliases.unregister(name)
        conf.supybot.plugins.Alias.aliases.register(name,
                                                    registry.String(alias, ''))
        conf.supybot.plugins.Alias.aliases.get(name).register('locked',
                                                    registry.Boolean(lock, ''))
        setattr(self.__class__, name, f)
        self.aliases[name] = [alias, lock]

    def removeAlias(self, name, evenIfLocked=False):
        name = callbacks.canonicalName(name)
        if hasattr(self, name) and self.isCommand(name):
            if evenIfLocked or not self.aliases[name][1]:
                delattr(self.__class__, name)
                del self.aliases[name]
                conf.supybot.plugins.Alias.aliases.unregister(name)
            else:
                raise AliasError, 'That alias is locked.'
        else:
            raise AliasError, 'There is no such alias.'

    def add(self, irc, msg, args, name, alias):
        """<name> <alias>

        Defines an alias <name> that executes <alias>.  The <alias>
        should be in the standard "command argument [nestedcommand argument]"
        arguments to the alias; they'll be filled with the first, second, etc.
        arguments.  $1, $2, etc. can be used for required arguments.  @1, @2,
        etc. can be used for optional arguments.  $* simply means "all
        remaining arguments," and cannot be combined with optional arguments.
        """
        if ' ' not in alias:
            # If it's a single word, they probably want $*.
            alias += ' $*'
        try:
            self.addAlias(irc, name, alias)
            self.log.info('Adding alias %q for %q (from %s)',
                          name, alias, msg.prefix)
            irc.replySuccess()
        except AliasError, e:
            irc.error(str(e))
    add = wrap(add, ['commandName', 'text'])

    def remove(self, irc, msg, args, name):
        """<name>

        Removes the given alias, if unlocked.
        """
        try:
            self.removeAlias(name)
            self.log.info('Removing alias %q (from %s)', name, msg.prefix)
            irc.replySuccess()
        except AliasError, e:
            irc.error(str(e))
    remove = wrap(remove, ['commandName'])


Class = Alias

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