/**
* Check for the other atoms nearby in the fragment.
*
* @param candidateOxygen
* the candidate oxygen atom
* @param frag
* the frag
* @param proton
* the proton
*
* @return true, if successful
* @throws CloneNotSupportedException
* @throws CDKException
*/
private IAtomContainer checkForCompleteNeutralLoss(IAtomContainer frag, IAtom candidateAtom, double neutralLossMass)
{
IAtomContainer ret = new AtomContainer();
// create a copy from the original fragment
var part = new List<IBond>();
part = traverse(frag, candidateAtom, part);
var fragCopy = makeAtomContainer(candidateAtom, part);
// set properties again
var properties = frag.getProperties();
fragCopy.setProperties(properties);
// now get the other atoms from the neutral loss
var atomsToFind = new List<string>();
var addHydrogen = false;
// one hydrogen is lost with the neutral loss
if (neutralLoss[neutralLossMass].HydrogenDifference == -1)
{
foreach (var isotope in neutralLoss[neutralLossMass].ElementalComposition.isotopes().ToWindowsEnumerable<IIsotope>())
{
var c = neutralLoss[neutralLossMass].ElementalComposition.getIsotopeCount(isotope);
for (var i = 0; i < c; i++)
{
atomsToFind.Add(isotope.getSymbol());
}
}
}
else
{
foreach (var isotope in neutralLoss[neutralLossMass].TopoFragment.isotopes().ToWindowsEnumerable<IIsotope>())
{
var c = neutralLoss[neutralLossMass].ElementalComposition.getIsotopeCount(isotope);
for (var i = 0; i < c; i++)
{
atomsToFind.Add(isotope.getSymbol());
}
addHydrogen = true;
}
}
// at most 2 bonds between the oxygen and other atoms (at most 1 H and 2
// C)
var count = neutralLoss[neutralLossMass].Distance;
// list storing all atoms to be removed later on if complete neutral
// loss was found
var foundAtoms = new List<IAtom>();
// list storing all bonds to remove
var foundBonds = new List<IBond>();
// list storing all bonds already checked
var checkedBonds = new List<IBond>();
// list storing all checked atoms
var checkedAtoms = new List<IAtom>();
// queue storing all bonds to check for a particular distance
var bondQueue = new List<IBond>();
// List storing all bonds to be checked for the next distance
var bondsFurther = new List<IBond>();
// get all bonds from this atom distance = 1
var bondList = fragCopy.getConnectedBondsList(candidateAtom);
foreach (var bond in bondList.ToWindowsEnumerable<IBond>())
{
if (bond != null)
{
bondQueue.Add(bond);
}
}
var hydrogenStartAtom = neutralLoss[neutralLossMass].HydrogenOnStartAtom;
var firstBonds = true;
while (count > 0)
{
IBond currentBond = null;
if (bondQueue.Count > 0)
{
currentBond = bondQueue[bondQueue.Count - 1];
bondQueue.RemoveAt(bondQueue.Count - 1);
}
// check for already tried bonds
if (checkedBonds.Contains(currentBond) && currentBond != null)
{
continue;
}
else if (currentBond != null)
{
checkedBonds.Add(currentBond);
}
if (currentBond != null)
{
foreach (var atom in currentBond.atoms().ToWindowsEnumerable<IAtom>())
{
// check for already tried atoms
if (checkedAtoms.Contains(atom))
{
continue;
}
else
{
checkedAtoms.Add(atom);
}
if (firstBonds && atom.getSymbol().Equals("H"))
{
hydrogenStartAtom--;
}
// thats the starting atom
if (atom.getSymbol().Equals(candidateAtom.getSymbol()))
{
var removed = atomsToFind.Remove(candidateAtom.getSymbol());
if (removed)
{
foundAtoms.Add(atom);
// remove bond
if (!foundBonds.Contains(currentBond))
{
foundBonds.Add(currentBond);
}
}
// this bond has to be removed
else if (!foundBonds.Contains(currentBond) && atomsToFind.Contains(atom.getSymbol()))
{
foundBonds.Add(currentBond);
}
continue;
}
// found atom...remove it from the atoms to find list
// do not remove atoms from ring
if (atomsToFind.Contains(atom.getSymbol()) && !allRings.contains(atom) && atomsToFind.Count > 0)
{
var removed = atomsToFind.Remove(atom.getSymbol());
if (removed)
{
foundAtoms.Add(atom);
}
else
{
continue;
}
if (!foundBonds.Contains(currentBond))
{
foundBonds.Add(currentBond);
}
continue;
}
// only walk along C-Atoms!
if (!atom.getSymbol().Equals("C"))
{
continue;
}
// get new bonds
var bondsToAddTemp = fragCopy.getConnectedBondsList(atom);
foreach (var bond in bondsToAddTemp.ToWindowsEnumerable<IBond>())
{
if (bond != null)
{
bondsFurther.Add(bond);
}
}
}
}
// break condition
if (currentBond == null && bondQueue.Count == 0 && bondsFurther.Count == 0)
{
break;
}
// now check if the queue is empty...checked all bonds in this
// distance
if (bondQueue.Count == 0)
{
count--;
// set new queue data
foreach (var bond in bondsFurther)
{
if (bond != null)
{
bondQueue.Add(bond);
}
}
// reinitialize
bondsFurther = new List<IBond>();
// the initially connected bonds are all checked!
firstBonds = false;
}
}
// found complete neutral loss
if (atomsToFind.Count == 0)
{
foreach (var atom in foundAtoms)
{
fragCopy.removeAtomAndConnectedElectronContainers(atom);
}
// TODO add hydrogen somewhere
if (addHydrogen)
{
var props = fragCopy.getProperties();
props.put("hydrogenAddFromNL", "1");
fragCopy.setProperties(props);
}
// add fragment to return if enough H were connected and fragment is
// still connected
if (hydrogenStartAtom <= 0)
{
ret.add(fragCopy);
}
}
return ret;
}
