PositionableList.java

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 *
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 * to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
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package jsettlers.logic.map.grid.partition.manager.datastructures;

import java8.util.function.Consumer;
import jsettlers.common.position.ILocatable;
import jsettlers.common.position.ShortPoint2D;
import jsettlers.common.utils.MathUtils;

import java.io.Serializable;
import java.util.Iterator;
import java.util.LinkedList;

/**
 * This is a data structure for storing and retrieving objects at given positions.<br>
 * It is also possible to find the nearest object around a given position.
 *
 * @param <T>
 * @author Andreas Eberle
 */
public class PositionableList<T extends ILocatable> implements Serializable {
	private static final long serialVersionUID = 414099060331344505L;

	protected final LinkedList<T> data;

	public PositionableList() {
		data = new LinkedList<>();
	}

	public void insert(T object) {
		data.add(object);
	}

	public T removeObjectAt(ShortPoint2D position) {
		Iterator<T> iterator = data.iterator();
		while (iterator.hasNext()) {
			T curr = iterator.next();
			if (curr.getPos().equals(position)) {
				iterator.remove();
				return curr;
			}
		}
		return null;
	}

	/**
	 * Returns the first object found at the given position or null.
	 *
	 * @param position
	 * 		The position to look for.
	 * @return Returns the found object at the given position or null if no object has been found.
	 */
	public T getObjectAt(ShortPoint2D position) {
		for (T curr : data) {
			if (curr.getPos().equals(position)) {
				return curr;
			}
		}
		return null;
	}

	/**
	 * Finds the object that's closest to the given position and removes it.
	 *
	 * @param position
	 * 		position to be used to find the nearest accepted neighbor around it.
	 * @return accepted object that's nearest to position
	 */
	public T removeObjectNextTo(ShortPoint2D position) {
		T currBest = getObjectCloseTo(position);

		if (currBest != null) {
			data.remove(currBest);
		}

		return currBest;
	}

	protected T getObjectCloseTo(ShortPoint2D position) {
		int bestDistance = Integer.MAX_VALUE;
		T currBest = null;

		for (T currEntry : data) {
			int currDist = MathUtils.squareHypot(position, currEntry.getPos());

			if (bestDistance > currDist) {
				bestDistance = currDist;
				currBest = currEntry;
			}
		}
		return currBest;
	}

	@Override
	public String toString() {
		return data.toString();
	}

	public void moveAll(PositionableList<T> otherList) {
		LinkedList<T> othersData = otherList.data;
		data.addAll(othersData);
		othersData.clear();
	}

	public void moveAll(PositionableList<T> otherList, Consumer<T> movedVisitor) {
		LinkedList<T> othersData = otherList.data;
		for (T othersDatum : othersData) {
			movedVisitor.accept(othersDatum);
			data.add(othersDatum);
		}
		othersData.clear();
	}

	public void remove(T object) {
		this.data.remove(object);
	}

	public boolean isEmpty() {
		return data.isEmpty();
	}

	public void moveObjectsAtPositionTo(ShortPoint2D position, PositionableList<T> newList, Consumer<T> movedVisitor) {
		Iterator<T> iterator = data.iterator();
		while (iterator.hasNext()) {
			T curr = iterator.next();
			if (curr.getPos().equals(position)) {
				iterator.remove();
				movedVisitor.accept(curr);
				newList.data.add(curr);
			}
		}
	}

	public int size() {
		return data.size();
	}
}