#!/usr/bin/python
#
# Rajarshi Guha <rajarshi@presidency.com>
# 23/02/2005
#

import string,sys,getopt,os

def usage():
    print """
    Splits an SDF file containing multiple structures into individual
    SDF files.
    
    Usage: splitsdf.py [OPTIONS] 

    -b,--base       Basename of resultant files. 
    -f,--file       SDF to split
    -h,--help       This message
    -v,--verbose    Verbose output

    If basename is given as XXX, then the resultant files will
    called XXX?.sdf where ? will be a zero padded integer. The default
    value is the basname of the input file.

    The resultant files are placed in the current working directory
    """

if __name__ == '__main__':
   
    inputfile = ''
    base = ''
    verbose = 0
    
    try:
        opt,args = getopt.getopt(sys.argv[1:], 'b:f:hv',\
        ['base=','file=','help=','verbose'])
    except getopt.GetoptError:
        usage()
        sys.exit(0)

    for o,a in opt:
        if o in ('-h','--help'):
            usage()
            sys.exit(0)
        if o in ('-f','--file'):
            inputfile = a
        if o in ('-b','--base'):
            base = a
        if o in ('-v','--verbose'):
            verbose = 1
    
    if inputfile == '':
        usage()
        sys.exit(0)
    
    cnt  = 1
    sdffile = open(inputfile,'r')

    if base == '':
        base = string.split(inputfile,".")[0]
    
    outfile = open('%s%05d.sdf' % (base,cnt) ,'w')
    for line in sdffile:
        if string.find(line,'$$$$') == 0:
            if verbose: print 'Done with molecule %d' % (cnt)
            outfile.close()
            #sdffile.readline()
            cnt = cnt + 1
            outfile = open('%s%05d.sdf' % (base,cnt) ,'w')
        else: 
            outfile.write(line)
    os.system('rm  %s%05d.sdf' % (base,cnt))       
    if verbose: print 'Done'