#!/usr/bin/env python

###
# Copyright (c) 2002-2004, Jeremiah Fincher
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###

"""
Provides commands available only on Unix.
"""

__revision__ = "$Id$"

import supybot.plugins as plugins

import os
import re
import pwd
import sys
import crypt
import errno
import popen2
import random
import select
import string
import struct


import supybot.conf as conf
import supybot.utils as utils
import supybot.privmsgs as privmsgs
import supybot.callbacks as callbacks

def configure(advanced):
    from supybot.questions import output, expect, anything, something, yn
    conf.registerPlugin('Unix', True)
    spellCmd = utils.findBinaryInPath('aspell')
    if not spellCmd:
        spellCmd = utils.findBinaryInPath('ispell')
    if not spellCmd:
        output("""NOTE: I couldn't find aspell or ispell in your path, so that
                  function of this module will not work.  You may choose to
                  install it later.  To re-enable the command then, give the
                  bot the command 'enable Unix.spell'.""")
        capabilities = conf.supybot.capabilities()
        capabilities.add('-Unix.spell')
        conf.supybot.capabilities.setValue(capabilities)
    fortuneCmd = utils.findBinaryInPath('fortune')
    if not fortuneCmd:
        output("""NOTE: I couldn't find fortune in your path, so that function
                  of this module will not work.  You may choose to install it
                  later.  To re-enable this command then, give the bot the
                  command 'enable Unix.fortune'.""")
        capabilities = conf.supybot.capabilities()
        capabilities.add('-Unix.fortune')
        conf.supybot.capabilities.setValue(capabilities)
    wtfCmd = utils.findBinaryInPath('wtf')
    if not wtfCmd:
        output("""NOTE: I couldn't find wtf in your path, so that function of
                  this module won't work.  You may choose to install it later;
                  to re-enable this command then, give the bot the command
                  'enable Unix.wtf'.""")
        capabilities = conf.supybot.capabilities()
        capabilities.add('-Unix.wtf')
        conf.supybot.capabilities.setValue(capabilities)
    output("""The "progstats" command can reveal potentially sensitive
              information about your machine. Here's an example of its output:

              %s\n""" % progstats())
    if yn('Would you like to disable this command for non-owner users?',
          default=True):
        capabilities = conf.supybot.capabilities()
        capabilities.add('-Unix.progstats')
        conf.supybot.capabilities.setValue(capabilities)

def progstats():
    pw = pwd.getpwuid(os.getuid())
    response = 'Process ID %i running as user "%s" and as group "%s" ' \
               'from directory "%s" with the command line "%s".  ' \
               'Running on Python %s.' % \
               (os.getpid(), pw[0], pw[3],
                os.getcwd(), " ".join(sys.argv),
                sys.version.translate(string.ascii, '\r\n'))
    return response

class TimeoutError(IOError):
    pass

def pipeReadline(fd, timeout=2):
    (r, _, _) = select.select([fd], [], [], timeout)
    if r:
        return r[0].readline()
    else:
        raise TimeoutError



class Unix(callbacks.Privmsg):
    def __init__(self):
        callbacks.Privmsg.__init__(self)
        self.spellCmd = utils.findBinaryInPath('aspell')
        if not self.spellCmd:
            self.spellCmd = utils.findBinaryInPath('ispell')
        self.fortuneCmd = utils.findBinaryInPath('fortune')
        self.wtfCmd = utils.findBinaryInPath('wtf')

    def errno(self, irc, msg, args):
        """<error number or code>

        Returns the number of an errno code, or the errno code of a number.
        """
        s = privmsgs.getArgs(args)
        try:
            i = int(s)
            name = errno.errorcode[i]
        except ValueError:
            name = s.upper()
            try:
                i = getattr(errno, name)
            except AttributeError:
                irc.reply('I can\'t find the errno number for that code.')
                return
        except KeyError:
            name = '(unknown)'
        irc.reply('%s (#%s): %s' % (name, i, os.strerror(i)))

    def progstats(self, irc, msg, args):
        """takes no arguments

        Returns various unix-y information on the running supybot process.
        """
        irc.reply(progstats())

    _cryptre = re.compile(r'[./0-9A-Za-z]')
    def crypt(self, irc, msg, args):
        """<password> [<salt>]

        Returns the resulting of doing a crypt() on <password>  If <salt> is
        not given, uses a random salt.  If running on a glibc2 system,
        prepending '$1$' to your salt will cause crypt to return an MD5sum
        based crypt rather than the standard DES based crypt.
        """
        def makeSalt():
            s = '\x00'
            while self._cryptre.sub('', s) != '':
                s = struct.pack('<h', random.randrange(2**16))
            return s
        (password, salt) = privmsgs.getArgs(args, optional=1)
        if salt == '':
            salt = makeSalt()
        irc.reply(crypt.crypt(password, salt))

    def spell(self, irc, msg, args):
        """<word>

        Returns the result of passing <word> to aspell/ispell.  The results
        shown are sorted from best to worst in terms of being a likely match
        for the spelling of <word>.
        """
        # We are only checking the first word
        if not self.spellCmd:
           irc.error('A spell checking command doesn\'t seem to be '
                          'installed on this computer.')
           return
        word = privmsgs.getArgs(args)
        if word and not word[0].isalpha():
            irc.error('<word> must begin with an alphabet character.')
            return
        if ' ' in word:
            irc.error('Spaces aren\'t allowed in the word.')
            return
        try:
            (r, w) = popen2.popen4([self.spellCmd, '-a'])
            s = r.readline() # Banner, hopefully.
            if 'sorry' in s.lower():
                irc.error(s)
                return
            w.write(word)
            w.write('\n')
            w.flush()
            try:
                line = pipeReadline(r)
                # aspell puts extra whitespace, ignore it
                while not line.strip('\r\n'):
                    line = pipeReadline(r)
            except TimeoutError:
                irc.error('The spell command timed out.')
                return
        finally:
            r.close()
            w.close()
        # parse the output
        if line[0] in '*+':
            resp = '"%s" may be spelled correctly.' % word
        elif line[0] == '#':
            resp = 'I could not find an alternate spelling for "%s"' % word
        elif line[0] == '&':
            matches = line.split(':')[1].strip()
            resp = 'Possible spellings for %r: %s.' % \
                   (word, utils.commaAndify(matches.split(', ')))
        else:
            resp = 'Something unexpected was seen in the [ai]spell output.'
        irc.reply(resp)

    def fortune(self, irc, msg, args):
        """takes no arguments

        Returns a fortune from the *nix fortune program.
        """
        if self.fortuneCmd is not None:
            (r, w) = popen2.popen4('%s -s' % self.fortuneCmd)
            s = r.read()
            w.close()
            r.close()
            irc.reply(' '.join(s.split()))
        else:
            irc.error('I couldn\'t find the fortune command.')

    def wtf(self, irc, msg, args):
        """[is] <something>

        Returns wtf <something> is.  'wtf' is a *nix command that first
        appeared in NetBSD 1.5.  In most *nices, it's available in some sort
        of 'bsdgames' package.
        """
        if self.wtfCmd is not None:
            if args and args[0] == 'is':
                del args[0]
            something = privmsgs.getArgs(args)
            something = something.rstrip('?')
            (r, w) = popen2.popen4([self.wtfCmd, something])
            response = utils.normalizeWhitespace(r.readline().strip())
            irc.reply(response)
            r.close()
            w.close()
        else:
            irc.error('I couldn\'t find the wtf command.')


Class = Unix
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