# $Id$
#
# Copyright (C) 2002-2010 greg Landrum and Rational Discovery LLC
#
#   @@ All Rights Reserved @@
#  This file is part of the RDKit.
#  The contents are covered by the terms of the BSD license
#  which is included in the file license.txt, found at the root
#  of the RDKit source tree.
#
""" functions to match a bunch of fragment descriptors from a file

No user-servicable parts inside.  ;-)

"""
import os
from rdkit import RDConfig
from rdkit import Chem


defaultPatternFileName = os.path.join(RDConfig.RDDataDir,'FragmentDescriptors.csv')

def _CountMatches(mol,patt,unique=True):
  return len(mol.GetSubstructMatches(patt,uniquify=unique))

fns = []
def _LoadPatterns(fileName=None):
  if fileName is None:
    fileName = defaultPatternFileName
  try:
    with open(fileName,'r') as inF:
      for line in inF.readlines():
        if len(line) and line[0] != '#':
          splitL = line.split('\t')
          if len(splitL)>=3:
            name = splitL[0]
            descr = splitL[1]
            sma = splitL[2]
            descr=descr.replace('"','')
            ok=1
            try:
              patt = Chem.MolFromSmarts(sma)
            except:
              ok=0
            else:
              if not patt or patt.GetNumAtoms()==0: ok=0
            if not ok: raise ImportError('Smarts %s could not be parsed'%(repr(sma)))
            fn = lambda mol,countUnique=True,pattern=patt:_CountMatches(mol,pattern,unique=countUnique)
            fn.__doc__ = descr
            name = name.replace('=','_')
            name = name.replace('-','_')
            fns.append((name,fn))
  except IOError:
    pass
        
_LoadPatterns()            
for name,fn in fns:
  exec('%s=fn'%(name))
fn=None