# $Id$
#
#  Copyright (C) 2005-2006 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.
#
import random
from rdkit.six.moves import range
from rdkit import Chem


def RandomizeMolBlock(molB):
  splitB = molB.split('\n')
  res = []
  res.extend(splitB[0:3])
  idx = 3
  inL = splitB[idx]
  res.append(inL)
  nAts = int(inL[0:3])
  nBonds = int(inL[3:6])

  idx += 1
  atLines = splitB[idx:idx + nAts]

  order = list(range(nAts))
  random.shuffle(order, random=random.random)

  for i in order:
    res.append(atLines[i])

  #print 'ORDER:',order
  idx += nAts
  for i in range(nBonds):
    inL = splitB[idx]
    idx1 = int(inL[0:3]) - 1
    idx2 = int(inL[3:6]) - 1
    idx1 = order.index(idx1)
    idx2 = order.index(idx2)
    inL = '% 3d% 3d' % (idx1 + 1, idx2 + 1) + inL[6:]
    res.append(inL)
    idx += 1
  res.append('M  END')
  return '\n'.join(res)


def RandomizeMol(mol):
  mb = Chem.MolToMolBlock(mol)
  #print '-----------------'
  #print mb
  mb = RandomizeMolBlock(mb)
  #print mb
  return Chem.MolFromMolBlock(mb)


def CheckCanonicalization(mol, nReps=10):
  refSmi = Chem.MolToSmiles(mol, False)
  for i in range(nReps):
    m2 = RandomizeMol(mol)
    smi = Chem.MolToSmiles(m2, False)
    if smi != refSmi:
      raise ValueError('\nRef: %s\n   : %s' % (refSmi, smi))


if __name__ == '__main__':
  from rdkit.Chem import Randomize
  CheckCanonicalization(Chem.MolFromSmiles('CON'))
  CheckCanonicalization(Chem.MolFromSmiles('c1ccccn1'))
  CheckCanonicalization(Chem.MolFromSmiles('C/C=C/F'))
