/* Copyright (C) 2010  Egon Willighagen <egonw@users.sf.net>
 *
 * Contact: cdk-devel@lists.sourceforge.net
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 */
package org.openscience.cdk.qsar.descriptors.molecular;

import java.util.ArrayList;
import java.util.List;

import org.openscience.cdk.aromaticity.Aromaticity;
import org.openscience.cdk.exception.CDKException;
import org.openscience.cdk.interfaces.IAtom;
import org.openscience.cdk.interfaces.IAtomContainer;
import org.openscience.cdk.interfaces.IChemObjectBuilder;
import org.openscience.cdk.qsar.AbstractMolecularDescriptor;
import org.openscience.cdk.qsar.DescriptorSpecification;
import org.openscience.cdk.qsar.DescriptorValue;
import org.openscience.cdk.qsar.IMolecularDescriptor;
import org.openscience.cdk.qsar.result.IDescriptorResult;
import org.openscience.cdk.qsar.result.IntegerResult;
import org.openscience.cdk.qsar.result.IntegerResultType;
import org.openscience.cdk.smarts.SmartsPattern;
import org.openscience.cdk.tools.manipulator.AtomContainerManipulator;

/**
 * Returns the number of acidic groups. The list of acidic groups is defined
 * by these SMARTS "$([O;H1]-[C,S,P]=O)", "$([*;-;!$(*~[*;+])])",
 * "$([NH](S(=O)=O)C(F)(F)F)", and "$(n1nnnc1)" originally presented in
 * JOELib {@cdk.cite WEGNER2006}.
 *
 * @author      egonw
 * @cdk.module  qsarmolecular
 * @cdk.githash
 * @cdk.dictref qsar-descriptors:acidicGroupCount
 */
public class AcidicGroupCountDescriptor extends AbstractMolecularDescriptor implements IMolecularDescriptor {

    private final static String[] SMARTS_STRINGS = {"[$([O;H1]-[C,S,P]=O)]", "[$([*;-;!$(*~[*;+])])]",
            "[$([NH](S(=O)=O)C(F)(F)F)]", "[$(n1nnnc1)]"};
    private final static String[] NAMES          = {"nAcid"};

    private List<SmartsPattern> tools  = new ArrayList<SmartsPattern>();
    private boolean               checkAromaticity;

    /**
     * Creates a new {@link AcidicGroupCountDescriptor}.
     */
    public AcidicGroupCountDescriptor() {
        this.checkAromaticity = true;
    }

    @Override
    public void initialise(IChemObjectBuilder builder) {
        for (String smarts : SMARTS_STRINGS) {
            tools.add(SmartsPattern.create(smarts));
        }
    }

    /** {@inheritDoc} */
    @Override
    public DescriptorSpecification getSpecification() {
        return new DescriptorSpecification(
                "http://www.blueobelisk.org/ontologies/chemoinformatics-algorithms/#acidicGroupCount", this.getClass()
                        .getName(), "The Chemistry Development Kit");
    }

    /** {@inheritDoc} */
    @Override
    public void setParameters(Object[] params) throws CDKException {
        if (params.length != 1) {
            throw new CDKException("AcidicGroupCountDescriptor requires 1 parameter.");
        }
        if (!(params[0] instanceof Boolean)) {
            throw new CDKException("The parameter must be of type Boolean");
        }

        // ok, all should be fine
        this.checkAromaticity = (Boolean) params[0];

    }

    /** {@inheritDoc} */
    @Override
    public Object[] getParameters() {
        Object params[] = new Object[1];
        params[0] = this.checkAromaticity;
        return (params);
    }

    /** {@inheritDoc} */
    @Override
    public String[] getDescriptorNames() {
        return NAMES;
    }

    /** {@inheritDoc} */
    @Override
    public DescriptorValue calculate(IAtomContainer atomContainer) {

        if (tools.isEmpty()) {
            throw new IllegalStateException("descriptor is not initalised, invoke 'initalise' first");
        }

        atomContainer = clone(atomContainer); // don't mod original
        for (IAtom atom : atomContainer.atoms()) {
            if (atom.getImplicitHydrogenCount() == null)
                atom.setImplicitHydrogenCount(0);
        }

        // do aromaticity detection
        if (this.checkAromaticity) {
            try {
                AtomContainerManipulator.percieveAtomTypesAndConfigureAtoms(atomContainer);
                Aromaticity.cdkLegacy().apply(atomContainer);
            } catch (CDKException exception) {
                return getDummyDescriptorValue(exception);
            }
        }

        int count = 0;
        for (SmartsPattern tool : tools)
            count += tool.matchAll(atomContainer).count();
        return new DescriptorValue(getSpecification(), getParameterNames(),
                                   getParameters(), new IntegerResult(count),
                                   getDescriptorNames());
    }

    /** {@inheritDoc} */
    @Override
    public IDescriptorResult getDescriptorResultType() {
        return new IntegerResultType();
    }

    /** {@inheritDoc} */
    @Override
    public String[] getParameterNames() {
        String[] params = new String[1];
        params[0] = "checkAromaticity";
        return (params);

    }

    /** {@inheritDoc} */
    @Override
    public Object getParameterType(String name) {
        Object object = null;
        if (name.equals("checkAromaticity")) object = true;
        return (object);
    }

    private DescriptorValue getDummyDescriptorValue(Exception exception) {
        return new DescriptorValue(getSpecification(), getParameterNames(), getParameters(), new IntegerResult(-1),
                getDescriptorNames(), exception);
    }
}