package geniusweb.issuevalue;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Iterator;

import org.eclipse.jdt.annotation.NonNull;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;

import tudelft.utilities.immutablelist.Range;

/**
 * Internal iterator for NumberValues
 */
class NumberValueIterator implements Iterator<Value> {
	private final @NonNull Iterator<BigDecimal> it;

	@SuppressWarnings("null")
	public NumberValueIterator(@NonNull Range range) {
		it = range.iterator();
	}

	@Override
	public boolean hasNext() {
		return it.hasNext();
	}

	@Override
	public @NonNull NumberValue next() {
		return new NumberValue(it.next());
	}
}

/**
 * number range from low to high with given step size
 */
// disable the inherited deserializer to prevent getting into infinite loop...
@JsonDeserialize(using = JsonDeserializer.None.class)
@JsonAutoDetect(fieldVisibility = Visibility.ANY, getterVisibility = Visibility.NONE, setterVisibility = Visibility.NONE)
public class NumberValueSet implements ValueSet {

	private final @NonNull Range range;

	@SuppressWarnings("unused")
	@JsonCreator
	public NumberValueSet(@JsonProperty("range") @NonNull Range range) {
		if (range == null)
			throw new NullPointerException("Range must not be null");
		this.range = range;
	}

	/**
	 * number range from low to high with given step size
	 * 
	 * @param low      the lowest value in the list. Must be &le; high
	 * @param high     the highest value in the list
	 * @param stepsize the step size. Must be &gt; 0
	 */
	public NumberValueSet(@NonNull BigDecimal low, @NonNull BigDecimal high,
			@NonNull BigDecimal stepsize) {
		if (low == null || high == null || stepsize == null)
			throw new NullPointerException(
					"low, high and stepsize must be not null");
		if (stepsize.compareTo(BigDecimal.ZERO) <= 0) {
			throw new IllegalArgumentException(
					"stepsize must be >0 but is " + stepsize.toString());
		}
		if (low.compareTo(high) > 0) {
			throw new IllegalArgumentException("low must be <= high");
		}
		range = new Range(low, high, stepsize);
	}

	@NonNull
	/**
	 * @return the range defining this NumberValueSet.
	 */
	public Range getRange() {
		return range;

	}

	@Override
	public @NonNull NumberValue get(@NonNull BigInteger index) {
		if (index.compareTo(size()) > 0)
			throw new IndexOutOfBoundsException("" + index);
		return new NumberValue(range.get(index));
	}

	@Override
	public @NonNull BigInteger size() {
		return range.size();
	}

	@Override
	@NonNull
	//#PY #  BigInteger and long are both int in python.
	public NumberValue get(long index) {
		return get(BigInteger.valueOf(index));
	}

	@Override
	public @NonNull Iterator<@NonNull Value> iterator() {
		return new NumberValueIterator(range);
	}

	@Override
	public @NonNull String toString() {
		return "NumberValueSet[" + range.getLow().toString() + ","
				+ range.getHigh().toString() + "," + range.getStep().toString()
				+ "]";
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((range == null) ? 0 : range.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		NumberValueSet other = (NumberValueSet) obj;
		if (range == null) {
			if (other.range != null)
				return false;
		} else if (!range.equals(other.range))
			return false;
		return true;
	}

	@Override
	public boolean contains(@NonNull Value value) {
		if (!(value instanceof NumberValue))
			return false;
		return range.contains(((NumberValue) value).getValue());
	}
}