#! /usr/bin/env python

import os, sys, string, re, time, optparse

citationRexp = re.compile(r'(?P<ref>\[!.+?!\])', re.S)

def moveToBackup(infilename, timeformat='%y%m%d-%H%M'):
	
	inroot, extension = os.path.splitext(infilename)
	
	outname = '%s_%s%s' % (inroot, time.strftime(timeformat),extension)
	
	try:
		os.rename(infilename, outname)
	except IOError, msg:
		sys.exit("Error writing backup file %s: \n %s" % (outname,msg))
		
	return outname

def convertToBibtex(matchObj):
	"""Converts [!Zhang, 1993, zhang1993-3345!] to \citestring{zhang1993-3345};
	depends on the global citestring variable"""
	
	refDelim = ';'
	intraRefDelim = ','
	#citestring = 'citep'
	
	orig = matchObj.group('ref')
		
	reflist = orig[2:-2].split(refDelim)
	
	# get last element in each list resulting from splitting using intraRefDelim
	labelList = [x.split(intraRefDelim)[-1].strip() for x in reflist if x.strip() != '']
	labelList.sort()
	
	for l in labelList: all_refs_global[l] = ''
	
	out = (r'\%s{%s}') % (citestring, string.join(labelList,', '))
		
	#print orig, '-->', out
	
	return out


#def open_infile():
	

def replaceCitations(instring, rexp=citationRexp):
	"""Replaces citations enclosed by the specified tags with \cite{ref}
	style citations."""

	clist = citationRexp.findall(instring)
		
	outstring = rexp.sub(convertToBibtex, instring)
	return outstring, clist
	
class Option (optparse.Option):
    ATTRS = optparse.Option.ATTRS + ['required']

    def _check_required (self):
        if self.required and not self.takes_value():
            raise OptionError(
                "required flag set for option that doesn't take a value",
                 self)

    # Make sure _check_required() is called from the constructor!
    CHECK_METHODS = optparse.Option.CHECK_METHODS + [_check_required]

    def process (self, opt, value, values, parser):
        optparse.Option.process(self, opt, value, values, parser)
        parser.option_seen[self] = 1


class OptionParser(optparse.OptionParser):

    def _init_parsing_state (self):
        optparse.OptionParser._init_parsing_state(self)
        self.option_seen = {}

    def check_values (self, values, args):
        for option in self.option_list:
            if (isinstance(option, Option) and
                option.required and
                not self.option_seen.has_key(option)):
                self.error("%s not supplied" % option)
        return (values, args)

def main():
	
	usage = """usage: %prog [options]
	
Converts all citations enclosed by temporary citation markers in
the format [!Author, Year, Label!] to BibTeX format citations 
(i.e., \cite{Label}). 

Example:
%prog -f infile.tex -o outfile.tex -c citep"""

	version = '$Id: texref.py,v 1.1 2004/10/10 02:53:10 nghoffma Exp $'
	make_option = optparse.make_option
	
	# -h,--help and --version options are built-in
	
	option_list=[
	Option('-f','--infile', 
		dest='infile', help='input file', required=1),
	Option('-o','--outfile', dest='outfile', 
		help='name of outfile; replaces infile by default', default=None),
	Option('-c','--citestring', dest='citestring', 
		help='command to precede citations (ie, \command{Label})',
		default='cite'),
	Option('-v', '--verbose', action='store_true', 
		dest='verbose', help='be verbose'),
	Option('-l','--list', action='store_true', 
		dest='list_only', help='print a list of all refs and stop'),
	#make_option("--secret", help=SUPPRESS_HELP)
	]

	parser = OptionParser(usage=usage,
version=version,
option_list=option_list,
#conflict_handler='resolve'
)
	
	(options, args) = parser.parse_args()
		
	v = options.verbose
	list_only = options.list_only
	global citestring
	citestring = options.citestring
	
	infilename = options.infile
	infile = open(infilename)
	instring = infile.read()
	infile.close()
	
	outfilename = options.outfile
	
	####################################
	
	# global variable to hold all of the ref labels found
	global all_refs_global
	all_refs_global = {}
		
	newstring, citationList = replaceCitations(instring)
	
	all_refs = all_refs_global.keys()
	all_refs.sort()

	if all_refs == []:
		sys.exit('No unformatted references were found in %s ... Exiting' % infilename)
	elif v:
		print "Found %s references in %s citations." % (len(all_refs), len(citationList)) 	
	
	if list_only:
		for ref in all_refs: print ref
		sys.exit()

	if not outfilename:
		outfilename = infilename
		# make a backup copy if infile is to be replaced
		backup_filename = moveToBackup(infilename)
		if v: print 'Backed up "%s" to "%s"' % (infilename, backup_filename)
	
	# open a new file and write the output	
	if v: 
		print 'The LaTeX citation command is "%s"' % citestring
		print 'Writing %s with modified citations.' % outfilename
	
	outfile = open(outfilename,'w')
	outfile.write(newstring)
	outfile.close()
		
if __name__ == '__main__':
	main()