ponysay/src/ponysay.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

'''
ponysay - Ponysay, cowsay reimplementation for ponies
Copyright (C) 2012, 2013  Erkin Batu Altunbaş et al.

This program is free software. It comes without any warranty, to
the extent permitted by applicable law. You can redistribute it
and/or modify it under the terms of the Do What The Fuck You Want
To Public License, Version 2, as published by Sam Hocevar. See
http://sam.zoy.org/wtfpl/COPYING for more details.
'''
from common import *
from backend import *
from balloon import *
from spellocorrecter import *
from ucs import *
from kms import *
from list import *
from metadata import *



'''
This is the mane class of ponysay
'''
class Ponysay():
    '''
    Constructor
    '''
    def __init__(self):
        '''
        The user's home directory
        '''
        self.HOME = os.environ['HOME'] if 'HOME' in os.environ else ''
        if len(self.HOME) == 0:
            os.environ['HOME'] = self.HOME = os.path.expanduser('~')
        
        
        '''
        Parse a file name encoded with environment variables
        
        @param   file  The encoded file name
        @return        The target file name, None if the environment variables are not declared
        '''
        def parsefile(file):
            if '$' in file:
                buf = ''
                esc = False
                var = None
                for c in file:
                    if esc:
                        buf += c
                        esc = False
                    elif var is not None:
                        if c == '/':
                            var = os.environ[var] if var in os.environ else ''
                            if len(var) == 0:
                                return None
                            buf += var + c
                            var = None
                        else:
                            var += c
                    elif c == '$':
                        var = ''
                    elif c == '\\':
                        esc = True
                    else:
                        buf += c
                return buf
            return file
        
        
        ## Change system enviroment variables with ponysayrc
        for file in ('$XDG_CONFIG_HOME/ponysay/ponysayrc', '$HOME/.config/ponysay/ponysayrc', '$HOME/.ponysayrc', '/etc/ponysayrc'):
            file = parsefile(file)
            if (file is not None) and os.path.exists(file):
                with open(file, 'rb') as ponysayrc:
                    code = ponysayrc.read().decode('utf8', 'replace') + '\n'
                    env = os.environ
                    code = compile(code, file, 'exec')
                    exec(code)
                break
        
        self.HOME = os.environ['HOME'] if 'HOME' in os.environ else '' # in case ~/.ponysayrc changes it
        if len(self.HOME) == 0:
            os.environ['HOME'] = self.HOME = os.path.expanduser('~')
        
        
        '''
        Whether any unrecognised options was parsed, this should be set by the invoker before run()
        '''
        self.unrecognised = False
        
        
        '''
        Whether the program is execute in Linux VT (TTY)
        '''
        self.linuxvt = ('TERM' in os.environ) and (os.environ['TERM'] == 'linux')
        
        
        '''
        Whether the script is executed as ponythink
        '''
        self.isthink = sys.argv[0]
        if os.sep in self.isthink:
            self.isthink = self.isthink[self.isthink.rfind(os.sep) + 1:]
        if os.extsep in self.isthink:
            self.isthink = self.isthink[:self.isthink.find(os.extsep)]
        self.isthink = self.isthink.endswith('think')
        
        
        '''
        Whether stdin is piped
        '''
        self.pipelinein = not sys.stdin.isatty()
        
        '''
        Whether stdout is piped
        '''
        self.pipelineout = not sys.stdout.isatty()
        
        '''
        Whether stderr is piped
        '''
        self.pipelineerr = not sys.stderr.isatty()
        
        
        '''
        Whether KMS is used
        '''
        self.usekms = KMS.usingkms(self.linuxvt)
        
        
        '''
        Mode string that modifies or adds $ variables in the pony image
        '''
        self.mode = ''
        
        
        def share(file):
            def cat(a, b):
                if a is None:
                    return None
                return a + b
            return [cat(parsefile(item), file) for item in [
                    './',
                    '$XDG_DATA_HOME/ponysay/',
                    '$HOME/.local/share/ponysay/',
                    '/usr/share/ponysay/'
                   ]]
        
        
        '''
        The directories where pony files are stored, ttyponies/ are used if the terminal is Linux VT (also known as TTY) and not with KMS
        '''
        appendset = set()
        self.xponydirs = []
        _ponydirs = share('ponies/')
        for ponydir in _ponydirs:
            if (ponydir is not None) and os.path.isdir(ponydir) and (ponydir not in appendset):
                self.xponydirs.append(ponydir)
                appendset.add(ponydir)
        appendset = set()
        self.vtponydirs = []
        _ponydirs = share('ttyponies/')
        for ponydir in _ponydirs:
            if (ponydir is not None) and os.path.isdir(ponydir) and (ponydir not in appendset):
                self.vtponydirs.append(ponydir)
                appendset.add(ponydir)
        
        
        '''
        The directories where pony files are stored, extrattyponies/ are used if the terminal is Linux VT (also known as TTY) and not with KMS
        '''
        appendset = set()
        self.extraxponydirs = []
        _extraponydirs = share('extraponies/')
        for extraponydir in _extraponydirs:
            if (extraponydir is not None) and os.path.isdir(extraponydir) and (extraponydir not in appendset):
                self.extraxponydirs.append(extraponydir)
                appendset.add(extraponydir)
        appendset = set()
        self.extravtponydirs = []
        _extraponydirs = share('extrattyponies/')
        for extraponydir in _extraponydirs:
            if (extraponydir is not None) and os.path.isdir(extraponydir) and (extraponydir not in appendset):
                self.extravtponydirs.append(extraponydir)
                appendset.add(extraponydir)
        
        
        '''
        The directories where quotes files are stored
        '''
        appendset = set()
        self.quotedirs = []
        _quotedirs = share('quotes/')
        for quotedir in _quotedirs:
            if (quotedir is not None) and os.path.isdir(quotedir) and (quotedir not in appendset):
                self.quotedirs.append(quotedir)
                appendset.add(quotedir)
        
        
        '''
        The directories where balloon style files are stored
        '''
        appendset = set()
        self.balloondirs = []
        _balloondirs = share('balloons/')
        for balloondir in _balloondirs:
            if (balloondir is not None) and os.path.isdir(balloondir) and (balloondir not in appendset):
                self.balloondirs.append(balloondir)
                appendset.add(balloondir)
        
        
        '''
        ucsmap files
        '''
        appendset = set()
        self.ucsmaps = []
        _ucsmaps = share('ucsmap/')
        for ucsmap in _ucsmaps:
            if (ucsmap is not None) and os.path.isdir(ucsmap) and (ucsmap not in appendset):
                self.ucsmaps.append(ucsmap)
                appendset.add(ucsmap)
    
    
    
    '''
    Starts the part of the program the arguments indicate
    
    @param  args:ArgParser  Parsed command line arguments
    '''
    def run(self, args):
        if (args.argcount == 0) and not self.pipelinein:
            args.help()
            exit(254)
            return
        
        '''
        Test arguments written in negation-free disjunctive normal form
        
        @param   keys:*str|itr<str>  A list of keys and set of keys, any of which must exists, a set of keys only passes if all of those exists
        @return  :bool               Whether the check passed
        '''
        def test(*keys):
            for key in keys:
                if isinstance(key, str):
                    if args.opts[key] is not None:
                        return True
                else:
                    for skey in key:
                        if args.opts[skey] is None:
                            return False
                    return True
            return False
        
        ## Emulate termial capabilities
        if   test('-X'):  (self.linuxvt, self.usekms) = (False, False)
        elif test('-V'):  (self.linuxvt, self.usekms) = (True, False)
        elif test('-K'):  (self.linuxvt, self.usekms) = (True, True)
        self.ponydirs      = self.vtponydirs      if self.linuxvt and not self.usekms else self.xponydirs
        self.extraponydirs = self.extravtponydirs if self.linuxvt and not self.usekms else self.extraxponydirs
        
        ## Variadic variants of -f, -q &c
        for sign in ('-', '+'):
            for letter in ('f', 'F', 'q', 'Q'):
                ssl = sign + sign + letter
                sl = sign + letter
                if (ssl in args.opts) and (args.opts[ssl] is not None):
                    if args.opts[sl] is not None:  args.opts[sl] += args.opts[ssl]
                    else:                          args.opts[sl]  = args.opts[ssl]
        
        ## Save whether standard or extra ponies are used
        self.usingstandard = test('-f', '-F', '-q') # -Q
        self.usingextra    = test('+f', '-F') # +q -Q
        
        ## Run modes
        if   test('-h'):                                     args.help()
        elif test('-v'):                                     self.version()
        elif test('--quoters'):                              self.quoters(True, False)
        elif test('--Onelist', ('--onelist', '++onelist')):  self.onelist(True, True)
        elif test('--onelist'):                              self.onelist(True, False)
        elif test('++onelist'):                              self.onelist(False, True)
        elif test('+A', ('-L', '+L')):                       self.linklist(); self.__extraponies(); self.linklist()
        elif test('-A', ('-l', '+l')):                       self.list(); self.__extraponies(); self.list()
        elif test('-L'):                                     self.linklist()
        elif test('-l'):                                     self.list()
        elif test('+L'):                                     self.__extraponies(); self.linklist()
        elif test('+l'):                                     self.__extraponies(); self.list()
        elif test('-B'):                                     self.balloonlist()
        else:
            ## Colouring features
            if test('--colour-pony'):
                self.mode += '\033[' + ';'.join(args.opts['--colour-pony']) + 'm'
            else:
                self.mode += '\033[0m'
            if test('+c'):
                if args.opts['--colour-msg']    is None:  args.opts['--colour-msg']    = args.opts['+c']
                if args.opts['--colour-link']   is None:  args.opts['--colour-link']   = args.opts['+c']
                if args.opts['--colour-bubble'] is None:  args.opts['--colour-bubble'] = args.opts['+c']
            
            ## Other extra features
            self.__bestpony(args)
            self.__ucsremap(args)
            if test('-o'):
                self.mode += '$/= $$\\= $'
                args.message = ''
                self.ponyonly = True
            else:
                self.ponyonly = False
            if test('-i', '+i'):
                args.message = ''
            self.restriction = args.opts['-r']
            
            ## The stuff
            if test('-q'):
                if (len(args.opts['-q']) == 1) and ((args.opts['-q'][0] == '-f') or (args.opts['-q'][0] == '+f')):
                    if args.opts['-q'][0] == '-f':
                        args.opts['-q'] = args.files
                        if test('-f'):
                            args.opts['-q'] += args.opts['-f']
                self.quote(args)
            elif not self.unrecognised:
                self.print_pony(args)
            else:
                args.help()
                exit(255)
                return
    
    
    ##############################################
    ## Methods that run before the mane methods ##
    ##############################################
    
    '''
    Use extra ponies
    '''
    def __extraponies(self):
        ## If extraponies are used, change ponydir to extraponydir
        if args is None:
            self.ponydirs[:] = self.extraponydirs
            self.quotedirs[:] = [] ## TODO +q
    
    
    '''
    Use best.pony if nothing else is set
    
    @param  args:ArgParser     Parsed command line arguments
    '''
    def __bestpony(self, args):
        ## Set best.pony as the pony to display if none is selected
        def test(keys, strict):
            if strict:
                for key in keys:
                    if (args.opts[key] is not None) and (len(args.opts[key]) != 0):
                        return False
            else:
                for key in keys:
                    if args.opts[key] is not None:
                        return False
            return True
        keys = ['-f', '+f', '-F', '-q'] ## TODO +q -Q
        if test(keys, False):
            for ponydir in self.ponydirs:
                if os.path.isfile(ponydir + 'best.pony') or os.path.islink(ponydir + 'best.pony'):
                    pony = os.path.realpath(ponydir + 'best.pony') # Canonical path
                    if test(keys, True):
                        args.opts['-f'] = [pony]
                    else:
                        for key in keys:
                            if test(key, True):
                                args.opts[key] = [pony]
                    break
    
    
    '''
    Apply pony name remapping to args according to UCS settings
    
    @param  args:ArgParser  Parsed command line arguments
    '''
    def __ucsremap(self, args):
        ## Read UCS configurations
        env_ucs = os.environ['PONYSAY_UCS_ME'] if 'PONYSAY_UCS_ME' in os.environ else ''
        ucs_conf = 0
        if   env_ucs in ('yes',    'y', '1'):  ucs_conf = 1
        elif env_ucs in ('harder', 'h', '2'):  ucs_conf = 2
        
        ## Stop UCS is not used
        if ucs_conf == 0:
            return
        
        ## Read all lines in all UCS → ASCII map files
        maplines = []
        for ucsmap in self.ucsmaps:
            if os.path.isfile(ucsmap):
                with open(ucsmap, 'rb') as mapfile:
                    maplines += [line.replace('\n', '') for line in mapfile.read().decode('utf8', 'replace').split('\n')]
        
        ## Create UCS → ASCII mapping from read lines
        map = {}
        stripset = ' \t' # must be string, wtf! and way doesn't python's doc say so
        for line in maplines:
            if (len(line) > 0) and not (line[0] == '#'):
                s = line.index('→')
                ucs   = line[:s]    .strip(stripset)
                ascii = line[s + 1:].strip(stripset)
                map[ucs] = ascii
        
        ## Apply UCS → ASCII mapping to -f, +f, -F and -q arguments
        for flag in ('-f', '+f', '-F', '-q'): ## TODO +q -Q
            if args.opts[flag] is not None:
                for i in range(0, len(args.opts[flag])):
                    if args.opts[flag][i] in map:
                        args.opts[flag][i] = map[args.opts[flag][i]]
    
    
    #######################
    ## Auxiliary methods ##
    #######################
    
    '''
    Apply UCS:ise pony names according to UCS settings
    
    @param  ponies:list<str>      List of all ponies (of interrest)
    @param  links:map<str, str>?  Map to fill with simulated symlink ponies, may be `None`
    '''
    def __ucsise(self, ponies, links = None):
        ## Read UCS configurations
        env_ucs = os.environ['PONYSAY_UCS_ME'] if 'PONYSAY_UCS_ME' in os.environ else ''
        ucs_conf = 0
        if   env_ucs in ('yes',    'y', '1'):  ucs_conf = 1
        elif env_ucs in ('harder', 'h', '2'):  ucs_conf = 2
        
        ## Stop UCS is not used
        if ucs_conf == 0:
            return
        
        ## Read all lines in all UCS → ASCII map files
        maplines = []
        for ucsmap in self.ucsmaps:
            if os.path.isfile(ucsmap):
                with open(ucsmap, 'rb') as mapfile:
                    maplines += [line.replace('\n', '') for line in mapfile.read().decode('utf8', 'replace').split('\n')]
        
        ## Create UCS → ASCII mapping from read lines
        map = {}
        stripset = ' \t' # must be string, wtf! and way doesn't python's doc say so
        for line in maplines:
            if not line.startswith('#'):
                s = line.index('→')
                ucs   = line[:s]    .strip(stripset)
                ascii = line[s + 1:].strip(stripset)
                map[ascii] = ucs
        
        ## Apply UCS → ACII mapping to ponies, by alias if weak settings
        if ucs_conf == 1:
            for pony in ponies:
                if pony in map:
                    ponies.append(map[pony])
                    if links is not None:
                        links[map[pony]] = pony
        else:
            for j in range(0, len(ponies)):
                if ponies[j] in map:
                    ponies[j] = map[ponies[j]]
    
    
    '''
    Returns one file with full path, names is filter for names, also accepts filepaths
    
    @param   names:list<str>?    Ponies to choose from, may be `None`
    @param   alt:bool            For method internal use...
    @param   ponydirs:itr<str>?  The pony directories to use
    @return  :str                The file name of a pony
    '''
    def __getponypath(self, names = None, alt = False, ponydirs = None):
        if ponydirs is None:  ponydirs = self.ponydirs
        ponies = {}
        
        ## List all pony files, without the .pony ending
        for ponydir in ponydirs:
            for ponyfile in os.listdir(ponydir):
                if endswith(ponyfile, '.pony'):
                    pony = ponyfile[:-5]
                    if pony not in ponies:
                        ponies[pony] = ponydir + ponyfile
        
        ## Support for explicit pony file names
        if names is not None:
            for name in names:
                if os.path.exists(name):
                    ponies[name] = name
        
        '''
        Get ponies that fit the terminal
        
        @param  fitting:add(str)→void  The set to fill
        @param  requirement:int        The maximum allowed value
        @param  file:istream           The file with all data
        '''
        def getfitting(fitting, requirement, file):
            data = file.read() # not too much data, can load everything at once
            ptr = 0
            while data[ptr] != 47: # 47 == ord('/')
                ptr += 1
            ptr += 1
            size = 0
            while data[ptr] != 47: # 47 == ord('/')
                size = (size * 10) - (data[ptr] & 15)
                ptr += 1
            ptr += 1
            jump = ptr - size
            stop = 0
            backjump = 0
            while ptr < jump:
                size = 0
                while data[ptr] != 47: # 47 == ord('/')
                    size = (size * 10) - (data[ptr] & 15)
                    ptr += 1
                ptr += 1
                if -size > requirement:
                    if backjump > 0:
                        ptr = backjump
                        while data[ptr] != 47: # 47 == ord('/')
                            stop = (stop * 10) - (data[ptr] & 15)
                            ptr += 1
                        stop = -stop
                    break
                backjump = ptr
                while data[ptr] != 47: # 47 == ord('/')
                    ptr += 1
                ptr += 1
            if ptr == jump:
                stop = len(data)
            else:
                ptr = jump
                stop += ptr
            passed = data[jump : stop].decode('utf8', 'replace').split('/')
            for pony in passed:
                fitting.add(pony)
            
        
        ## If there is not select ponies, choose all of them
        if (names is None) or (len(names) == 0):
            oldponies = ponies
            if self.restriction is not None:
                logic = Metadata.makeRestrictionLogic(self.restriction)
                ponies = {}
                for ponydir in ponydirs:
                    for pony in Metadata.restrictedPonies(ponydir, logic):
                        if (pony not in passed) and (pony in oldponies):
                            ponyfile = ponydir + pony + '.pony'
                            if oldponies[pony] == ponyfile:
                                ponies[pony] = ponyfile
                oldponies = ponies
            ponies = {}
            (termh, termw) = gettermsize()
            for ponydir in ponydirs:
                (fitw, fith) = (None, None)
                if os.path.exists(ponydir + 'widths'):
                    fitw = set()
                    with open(ponydir + 'widths', 'rb') as file:
                        getfitting(fitw, termw, file)
                if os.path.exists(ponydir + ('onlyheights' if self.ponyonly else 'heights')):
                    fith = set()
                    with open(ponydir + ('onlyheights' if self.ponyonly else 'heights'), 'rb') as file:
                        getfitting(fith, termh, file)
                for ponyfile in oldponies.values():
                    if ponyfile.startswith(ponydir):
                        pony = ponyfile[len(ponydir) : -5]
                        if (fitw is None) or (pony in fitw):
                            if (fith is None) or (pony in fith):
                                ponies[pony] = ponyfile
                #for ponyfile in os.listdir(ponydir):
                #    if endswith(ponyfile, '.pony'):
                #        pony = ponyfile[:-5]
                #        if pony not in ponies:
                #            if (fitw is None) or (pony in fitw):
                #                if (fith is None) or (pony in fith):
                #                    ponies[pony] = ponydir + ponyfile
            names = list((oldponies if len(ponies) == 0 else ponies).keys())
        
        ## Select a random pony of the choosen ones
        pony = names[random.randrange(0, len(names))]
        if pony not in ponies:
            if not alt:
                autocorrect = SpelloCorrecter(ponydirs, '.pony')
                (alternatives, dist) = autocorrect.correct(pony)
                limit = os.environ['PONYSAY_TYPO_LIMIT'] if 'PONYSAY_TYPO_LIMIT' in os.environ else ''
                limit = 5 if len(limit) == 0 else int(dist)
                if (len(alternatives) > 0) and (dist <= limit):
                    return self.__getponypath(alternatives, True)
            sys.stderr.write('I have never heard of anypony named %s\n' % (pony));
            if not self.usingstandard:
                sys.stderr.write('Use -f/-q or -F if it a MLP:FiM pony');
            if not self.usingexta:
                sys.stderr.write('Have you tested +f or -F?');
            exit(1)
        else:
            return ponies[pony]
    
    
    '''
    Returns a set with all ponies that have quotes and are displayable
    
    @param   ponydirs:itr<str>   The pony directories to use
    @param   quotedirs:itr<str>  The quote directories to use
    @return  :set<str>           All ponies that have quotes and are displayable
    '''
    def __quoters(self, ponydirs = None, quotedirs = None):
        if ponydirs  is None:  ponydirs  = self.ponydirs
        if quotedirs is None:  quotedirs = self.quotedirs
        
        ## List all unique quote files
        quotes = []
        quoteshash = set()
        _quotes = []
        for quotedir in quotedirs:
            _quotes += [item[:item.index('.')] for item in os.listdir(quotedir)]
        for quote in _quotes:
            if not quote == '':
                if not quote in quoteshash:
                    quoteshash.add(quote)
                    quotes.append(quote)
        
        ## Create a set of all ponyes that have quotes
        ponies = set()
        for ponydir in ponydirs:
            for pony in os.listdir(ponydir):
                if not pony[0] == '.':
                    p = pony[:-5] # remove .pony
                    for quote in quotes:
                        if ('+' + p + '+') in ('+' + quote + '+'):
                            if not p in ponies:
                                ponies.add(p)
        
        return ponies
    
    
    '''
    Returns a list with all (pony, quote file) pairs
    
    @param   ponydirs:itr<str>         The pony directories to use
    @param   quotedirs:itr<str>        The quote directories to use
    @return  (pony, quote):(str, str)  All ponies–quote file-pairs
    '''
    def __quotes(self, ponydirs = None, quotedirs = None):
        if ponydirs  is None:  ponydirs  = self.ponydirs
        if quotedirs is None:  quotedirs = self.quotedirs
        
        ## Get all ponyquote files
        quotes = []
        for quotedir in quotedirs:
            quotes += [quotedir + item for item in os.listdir(quotedir)]
        
        ## Create list of all pony–quote file-pairs
        rc = []
        for ponydir in ponydirs:
            for pony in os.listdir(ponydir):
                if not pony[0] == '.':
                    p = pony[:-5] # remove .pony
                    for quote in quotes:
                        q = quote[quote.rindex('/') + 1:]
                        q = q[:q.rindex('.')]
                        if ('+' + p + '+') in ('+' + q + '+'):
                            rc.append((p, quote))
        
        return rc
    
    
    
    #####################
    ## Listing methods ##
    #####################
    
    
    '''
    Lists the available ponies
    
    @param  ponydirs:itr<str>  The pony directories to use
    '''
    def list(self, ponydirs = None):
        List.simplelist(self.ponydirs if ponydirs is None else ponydirs,
                        self.__quoters(), lambda x : self.__ucsise(x))
    
    
    '''
    Lists the available ponies with alternatives inside brackets
    
    @param  ponydirs:itr<str>  The pony directories to use
    '''
    def linklist(self, ponydirs = None):
        List.linklist(self.ponydirs if ponydirs is None else ponydirs,
                      self.__quoters(), lambda x, y : self.__ucsise(x, y))
    
    
    '''
    Lists the available ponies on one column without anything bold or otherwise formated
    
    @param  standard:bool  Include standard ponies
    @param  extra:bool     Include extra ponies
    '''
    def onelist(self, standard = True, extra = False):
        List.onelist(self.ponydirs if standard else None,
                     self.extraponydirs if extra else None,
                     lambda x : self.__ucsise(x))
    
    
    '''
    Lists with all ponies that have quotes and are displayable, on one column without anything bold or otherwise formated
    
    @param  standard:bool  Include standard ponies
    @param  extra:bool     Include extra ponies
    '''
    def quoters(self, standard = True, extra = False):
        ## Get all quoters
        ponies = list(self.__quoters()) if standard else []
        
        ## And now the extra ponies
        if extra:
            self.__extraponies()
            ponies += list(self.__quoters())
        
        ## UCS:ise here
        self.__ucsise(ponies)
        ponies.sort()
        
        ## Print each one on a seperate line, but skip duplicates
        last = ''
        for pony in ponies:
            if not pony == last:
                last = pony
                print(pony)
    
    
    #####################
    ## Balloon methods ##
    #####################
    
    '''
    Prints a list of all balloons
    '''
    def balloonlist(self):
        List.balloonlist(self.balloondirs, self.isthink)
    
    
    '''
    Returns one file with full path, names is filter for style names, also accepts filepaths
    
    @param  names:list<str>  Balloons to choose from, may be `None`
    @param  alt:bool         For method internal use
    @param  :str             The file name of the balloon, will be `None` iff `names` is `None`
    '''
    def __getballoonpath(self, names, alt = False):
        ## Stop if their is no choosen balloon
        if names is None:
            return None
        
        ## Get all balloons
        balloons = {}
        for balloondir in self.balloondirs:
            for balloon in os.listdir(balloondir):
                balloonfile = balloon
                ## Use .think if running ponythink, otherwise .say
                if self.isthink and endswith(balloon, '.think'):
                    balloon = balloon[:-6]
                elif (not self.isthink) and endswith(balloon, '.say'):
                    balloon = balloon[:-4]
                else:
                    continue
                
                ## Add the balloon if there is none with the same name
                if balloon not in balloons:
                    balloons[balloon] = balloondir + balloonfile
        
        ## Support for explicit balloon file names
        for name in names:
            if os.path.exists(name):
                balloons[name] = name
        
        ## Select a random balloon of the choosen ones
        balloon = names[random.randrange(0, len(names))]
        if balloon not in balloons:
            if not alt:
                autocorrect = SpelloCorrecter(self.balloondirs, '.think' if self.isthink else '.say')
                (alternatives, dist) = autocorrect.correct(balloon)
                limit = os.environ['PONYSAY_TYPO_LIMIT'] if 'PONYSAY_TYPO_LIMIT' in os.environ else ''
                limit = 5 if len(limit) == 0 else int(dist)
                if (len(alternatives) > 0) and (dist <= limit):
                    return self.__getballoonpath(alternatives, True)
            printerr('That balloon style %s does not exist' % (balloon));
            exit(1)
        else:
            return balloons[balloon]
    
    
    '''
    Creates the balloon style object
    
    @param   balloonfile:str  The file with the balloon style, may be `None`
    @return  :Balloon         Instance describing the balloon's style
    '''
    def __getballoon(self, balloonfile):
        return Balloon.fromfile(balloonfile, self.isthink)
    
    
    
    ########################
    ## Displaying methods ##
    ########################
    
    '''
    Prints the name of the program and the version of the program
    '''
    def version(self):
        ## Prints the "ponysay $VERSION", if this is modified, ./dev/dist.sh must be modified accordingly
        print('%s %s' % ('ponysay', VERSION))
    
    
    '''
    Print the pony with a speech or though bubble. message, pony and wrap from args are used.
    
    @param  args:ArgParser  Parsed command line arguments
    '''
    def print_pony(self, args):
        ## Get message and remove tailing whitespace from stdin (but not for each line)
        if args.message == None:
            msg = ''.join(sys.stdin.readlines()).rstrip()
        else:
            msg = args.message
        if args.opts['--colour-msg'] is not None:
            msg = '\033[' + ';'.join(args.opts['--colour-msg']) + 'm' + msg
        
        ## This algorithm should give some result as cowsay's (according to tests)
        if args.opts['-c'] is not None:
            buf = ''
            last = ' '
            CHARS = '\t \n'
            for c in msg:
                if (c in CHARS) and (last in CHARS):
                    if last == '\n':
                        buf += last
                    last = c
                else:
                    buf += c
                    last = c
            msg = buf.strip(CHARS)
            buf = ''
            for c in msg:
                if (c != '\n') or (last != '\n'):
                    buf += c
                    last = c
            msg = buf.replace('\n', '\n\n')
        
        ## Get the pony
        pony = self.__getponypath(args.opts['-f'])
        printinfo('pony file: ' + pony)
        
        ## Use PNG file as pony file
        if endswith(pony.lower(), '.png'):
            pony = '\'' + pony.replace('\'', '\'\\\'\'') + '\''
            pngcmd = 'ponytool --import image --file %s --export ponysay --platform %s --balloon y'
            pngcmd %= (pony, ('linux' if self.linuxvt else 'xterm')) # XXX xterm should be haiku in Haiku
            pngpipe = os.pipe()
            Popen(pngcmd, stdout=os.fdopen(pngpipe[1], 'w'), shell=True).wait()
            pony = '/proc/' + str(os.getpid()) + '/fd/' + str(pngpipe[0])
        
        ## If KMS is utilies, select a KMS pony file and create it if necessary
        pony = KMS.kms(pony, self.HOME, self.linuxvt)
        
        ## If in Linux VT clean the terminal (See info/pdf-manual [Printing in TTY with KMS])
        if self.linuxvt:
            print('\033[H\033[2J', end='')
        
        ## Get width truncation and wrapping
        env_width = os.environ['PONYSAY_FULL_WIDTH'] if 'PONYSAY_FULL_WIDTH' in os.environ else None
        if env_width is None:  env_width = ''
        widthtruncation = gettermsize()[1] if env_width not in ('yes', 'y', '1') else None
        messagewrap = 40
        if (args.opts['-W'] is not None) and (len(args.opts['-W'][0]) > 0):
            messagewrap = args.opts['-W'][0]
            if messagewrap[0] in 'nmsNMS': # m is left to n on QWERTY and s is left to n on Dvorak
                messagewrap = None
            elif messagewrap[0] in 'iouIOU': # o is left to i on QWERTY and u is right to i on Dvorak
                messagewrap = gettermsize()[1]
            else:
                messagewrap = int(args.opts['-W'][0])
        
        ## Get balloon object
        balloonfile = self.__getballoonpath(args.opts['-b'][0] if args.opts['-b'] is not None else None)
        printinfo('balloon style file: ' + str(balloonfile))
        balloon = self.__getballoon(balloonfile) if args.opts['-o'] is None else None
        
        ## Get hyphen style
        hyphen = os.environ['PONYSAY_WRAP_HYPHEN'] if 'PONYSAY_WRAP_HYPHEN' in os.environ else None
        if (hyphen is None) or (len(hyphen) == 0):
            hyphen = '-'
        hyphencolour = ''
        if args.opts['--colour-wrap'] is not None:
            hyphencolour = '\033[' + ';'.join(args.opts['--colour-wrap']) + 'm'
        hyphen = '\033[31m' + hyphencolour + hyphen
        
        ## Link and balloon colouring
        linkcolour = ''
        if args.opts['--colour-link'] is not None:
            linkcolour = '\033[' + ';'.join(args.opts['--colour-link']) + 'm'
        ballooncolour = ''
        if args.opts['--colour-bubble'] is not None:
            ballooncolour = '\033[' + ';'.join(args.opts['--colour-bubble']) + 'm'
        
        ## Determine --info/++info settings
        minusinfo = args.opts['-i'] is not None
        plusinfo  = args.opts['+i'] is not None
        
        ## Run cowsay replacement
        backend = Backend(message = msg, ponyfile = pony, wrapcolumn = messagewrap, width = widthtruncation, balloon = balloon,
                          hyphen = hyphen, linkcolour = linkcolour, ballooncolour = ballooncolour, mode = self.mode,
                          infolevel = 2 if plusinfo else (1 if minusinfo else 0))
        backend.parse()
        output = backend.output
        if output.endswith('\n'):
            output = output[:-1]
        
        
        ## Load height trunction settings
        env_bottom = os.environ['PONYSAY_BOTTOM'] if 'PONYSAY_BOTTOM' in os.environ else None
        if env_bottom is None:  env_bottom = ''
        
        env_height = os.environ['PONYSAY_TRUNCATE_HEIGHT'] if 'PONYSAY_TRUNCATE_HEIGHT' in os.environ else None
        if env_height is None:  env_height = ''
        
        env_lines = os.environ['PONYSAY_SHELL_LINES'] if 'PONYSAY_SHELL_LINES' in os.environ else None
        if (env_lines is None) or (env_lines == ''):  env_lines = '2'
        
        ## Print the output, truncated on height is so set
        lines = gettermsize()[0] - int(env_lines)
        if self.linuxvt or (env_height is ('yes', 'y', '1')):
            if env_bottom is ('yes', 'y', '1'):
                for line in output.split('\n')[: -lines]:
                    print(line)
            else:
                for line in output.split('\n')[: lines]:
                    print(line)
        else:
            print(output)
    
    
    '''
    Print the pony with a speech or though bubble and a self quote
    
    @param  args:ArgParser  Parsed command line arguments
    '''
    def quote(self, args):
        ## Get all quotes, and if any pony is choosen just keep them
        pairs = self.__quotes()
        if len(args.opts['-q']) > 0:
            ponyset = {}
            for pony in args.opts['-q']:
                if endswith(pony, '.pony'):
                    ponyname = pony[:-5]
                    if '/' in ponyname:
                        ponyname = ponyname[ponyname.rindex('/') + 1:]
                    ponyset[ponyname] = pony
                else:
                    ponyset[pony] = pony
            alts = []
            for pair in pairs:
                if pair[0] in ponyset:
                    alts.append((ponyset[pair[0]], pair[1]))
            pairs = alts
        
        ## Select a random pony–quote-pair, load it and print it
        if not len(pairs) == 0:
            pair = pairs[random.randrange(0, len(pairs))]
            printinfo('quote file: ' + pair[1])
            with open(pair[1], 'rb') as qfile:
                args.message = qfile.read().decode('utf8', 'replace').strip()
            args.opts['-f'] = [pair[0]]
        elif len(args.opts['-q']) == 0:
            sys.stderr.write('Princess Celestia! All the ponies are mute!\n')
            exit(1)
        else:
            args.opts['-f'] = [args.opts['-q'][random.randrange(0, len(args.opts['-q']))]]
            args.message = 'Zecora! Help me, I am mute!'
        
        self.print_pony(args)