package geniusweb.actions;

import com.fasterxml.jackson.annotation.JsonValue;

/**
 * Unique ID of a party in a negotiation. The name should start with a short
 * string indicating the party (eg, the party name plus some machine
 * identifier), optionally followed by an "_", and more characters to make the
 * partyid unique. We require the name and "-" so that the string up to the
 * first "-" can be used to determine between sessions which opponents are
 * instances of the same class.
 * <h2>Note</h2> Normally, negotiation parties should not create new Party IDs
 * as all needed IDs should be provided by the protocol.
 */
public final class PartyId {
	@JsonValue
	private final String name;

	/**
	 * 
	 * @param name a simple name, starting with letter, followed by zero or more
	 *             letters, digits or _.
	 */
	public PartyId(String name) {
		if (name == null || !name.matches("[a-zA-Z]\\w*")) {
			throw new IllegalArgumentException("name '" + name
					+ "' is not a letter followed by zero or more word characters (letter, digit or _)");
		}
		this.name = name;
	}

	public String getName() {
		return name;
	}

	@Override
	public String toString() {
		return name;
	}

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

}