/*
 * This is eMonocot, a global online biodiversity information resource.
 *
 * Copyright © 2011–2015 The Board of Trustees of the Royal Botanic Gardens, Kew and The University of Oxford
 *
 * eMonocot is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero General Public License as published by the Free Software Foundation, either version 3
 * of the License, or (at your option) any later version.
 *
 * eMonocot 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 Affero General Public License for more details.
 *
 * The complete text of the GNU Affero General Public License is in the source repository as the file
 * ‘COPYING’.  It is also available from <http://www.gnu.org/licenses/>.
 */
package org.emonocot.portal.view.bibliography;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.List;
import java.util.SortedSet;
import java.util.TreeSet;

import org.apache.commons.collections.comparators.NullComparator;
import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;
import org.emonocot.model.Distribution;
import org.emonocot.model.Reference;
import org.emonocot.model.Taxon;
import org.emonocot.model.Description;
import org.emonocot.model.compare.ReferenceComparator;

/**
 *
 * @author ben
 *
 */
public class SimpleBibliographyImpl implements Bibliography {
	/**
	 *
	 */
	List<Reference> references = new ArrayList<Reference>();

	SortedSet<ReferenceWrapper> refs = new TreeSet<ReferenceWrapper>(new ReferenceWrapperComparator());

	/**
	 *
	 * @param taxon Set the taxon
	 */
	public final void setReferences(final Taxon taxon) {

		for(Reference reference : taxon.getReferences()) {
			refs.add(new ReferenceWrapper(reference));
		}
		for (Description d : taxon.getDescriptions()) {
			for(Reference reference : d.getReferences()) {
				refs.add(new ReferenceWrapper(reference));
			}
		}
		for (Distribution d : taxon.getDistribution()) {
			for(Reference reference : d.getReferences()) {
				refs.add(new ReferenceWrapper(reference));
			}
		}
		for(ReferenceWrapper ref : refs) {
			references.add(ref.reference);
		}
	}

	/**
	 *
	 * @param reference Set the reference
	 * @return A string key which can be displayed in the taxon page as a
	 *         citation reference to the reference
	 */
	public final String getKey(final Reference reference) {
		ReferenceWrapper referenceWrapper = new ReferenceWrapper(reference);
		ReferenceWrapper wrapper = null;
		for(ReferenceWrapper rw : refs) {
			if(rw.equals(referenceWrapper)) {
				wrapper = rw;
				break;
			}
		}
		return new Integer(references.indexOf(wrapper.reference) + 1).toString();
	}

	/**
	 *
	 * @return a sorted list of references
	 */
	public final List<Reference> getReferences() {
		return references;
	}

	/**
	 *
	 * @author ben
	 *
	 */
	class ReferenceWrapperComparator implements Comparator<ReferenceWrapper> {

		private Comparator<Reference> referenceComparator = new ReferenceComparator();

		/**
		 * @param o1
		 *            Set the first reference
		 * @param o2
		 *            Set the second reference
		 * @return 1 if o1 comes after o2, -1 if o1 comes before o2 and 0
		 *         otherwise
		 */
		public final int compare(final ReferenceWrapper o1, final ReferenceWrapper o2) {
			return referenceComparator.compare(o1.reference, o2.reference);
		}
	}

	@Override
	public SortedSet<String> getKeys(Collection<Distribution> distributions) {
		SortedSet<String> keys = new TreeSet<String>();
		for(Distribution d: distributions) {
			for(Reference r : d.getReferences()) {
				keys.add(getKey(r));
			}
		}
		return keys;
	}

	@Override
	public Reference getReference(String key) {
		Integer i = Integer.parseInt(key) - 1;
		return references.get(i);
	}

	class ReferenceWrapper {
		private Reference reference;

		public ReferenceWrapper(Reference reference) {
			this.reference = reference;
		}

		public int hashCode() {
			return new HashCodeBuilder(17, 31)
			.append(reference.getDate())
			.append(reference.getCreator())
			.append(reference.getTitle())
			.append(reference.getBibliographicCitation())
			.toHashCode();
		}

		public boolean equals(Object obj) {
			if (obj == null)
				return false;
			if (obj == this)
				return true;
			if (!(obj instanceof ReferenceWrapper))
				return false;

			ReferenceWrapper rhs = (ReferenceWrapper) obj;
			return new EqualsBuilder()
			.append(reference.getDate(), rhs.reference.getDate())
			.append(reference.getCreator(), rhs.reference.getCreator())
			.append(reference.getTitle(), rhs.reference.getTitle())
			.append(reference.getBibliographicCitation(), rhs.reference.getBibliographicCitation())
			.isEquals();
		}
	}
}