package policy.price.outline;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.Queue;

import foundation.json.IJSONProvider;
import foundation.json.IJSONWriter;
import policy.price.PriceLine;

public class PriceUpdateList implements Iterable<PriceUpdateRecord>, IJSONProvider {

	private int max;
	private Queue<PriceUpdateRecord> items;
	
	public PriceUpdateList() {
		items = new LinkedList<PriceUpdateRecord>();
		max = 10;
	}
	
	public PriceUpdateRecord loadOne(PriceLine priceLine) {
		PriceUpdateRecord record = new PriceUpdateRecord(priceLine);
		
		if (items.size() >= max) {
			items.poll();
		}
		
		items.add(record);
		return record;
	}

	@Override
	public void writeJSON(IJSONWriter writer) {
		writer.beginArray();
		
		for (PriceUpdateRecord record: items) {
			record.writeJSON(writer);
		}
		
		writer.endArray();
	}

	@Override
	public Iterator<PriceUpdateRecord> iterator() {
		return items.iterator();
	}
	
}