package geniusweb.inform;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonValue;

import geniusweb.actions.PartyId;
import geniusweb.issuevalue.Bid;

/**
 * There can be multiple agreements from a single negotiation. This object
 * contains the agreements. Each party can agree only on 1 bid and there are
 * always at least 2 parties agreeing on a bid.
 */
@JsonAutoDetect(fieldVisibility = Visibility.ANY, getterVisibility = Visibility.NONE, setterVisibility = Visibility.NONE)
public class Agreements {
	@JsonValue
	private final Map<PartyId, Bid> agreements;

	public Agreements() {
		this.agreements = Collections.emptyMap();
	}

	@JsonCreator
	public Agreements(Map<PartyId, Bid> agrees) {
		this.agreements = agrees;
	}

	/**
	 * @param bid     a bid that all parties agreed on
	 * @param parties the {@link PartyId}s of the agreeing parties
	 */
	public Agreements(Bid bid, Set<PartyId> parties) {
		this(parties.stream()
				.collect(Collectors.toMap(pid -> pid, pid -> bid)));
	}

	/**
	 * @param other {@link Agreements}
	 * @return a new Agreement containing this plus other agreements
	 * @throws IllegalArgumentException if parties in other are already in this
	 *                                  agreement.
	 */
	public Agreements with(Agreements other) {
		Map<PartyId, Bid> newagrees = new HashMap<>(agreements);
		for (PartyId pid : other.agreements.keySet()) {
			if (newagrees.containsKey(pid))
				throw new IllegalArgumentException(
						"party " + pid + " already has agreement");
			newagrees.put(pid, other.agreements.get(pid));
		}
		return new Agreements(newagrees);
	}

	/**
	 * @return actual agreemenets contained here
	 */
	public Map<PartyId, Bid> getMap() {
		return Collections.unmodifiableMap(agreements);
	}

	@Override
	public String toString() {
		return "Agreements" + agreements;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result
				+ ((agreements == null) ? 0 : agreements.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;
		Agreements other = (Agreements) obj;
		if (agreements == null) {
			if (other.agreements != null)
				return false;
		} else if (!agreements.equals(other.agreements))
			return false;
		return true;
	}

}