package net.onrc.onos.core.util;

import javax.annotation.concurrent.Immutable;

import net.onrc.onos.core.util.serializers.DpidDeserializer;
import net.onrc.onos.core.util.serializers.DpidSerializer;

import org.codehaus.jackson.map.annotate.JsonDeserialize;
import org.codehaus.jackson.map.annotate.JsonSerialize;
import org.projectfloodlight.openflow.util.HexString;

import com.google.common.primitives.Longs;

/**
 * The class representing a network switch DPID.
 * This class is immutable.
 */
@JsonDeserialize(using = DpidDeserializer.class)
@JsonSerialize(using = DpidSerializer.class)
@Immutable
public final class Dpid {
    private static final long UNKNOWN = 0;
    private final long value;

    /**
     * Default constructor.
     */
    protected Dpid() {
        this.value = Dpid.UNKNOWN;
    }

    /**
     * Constructor from a long value.
     *
     * @param value the value to use.
     */
    public Dpid(long value) {
        this.value = value;
    }

    /**
     * Constructor from a string.
     *
     * @param value the value to use.
     */
    public Dpid(String value) {
        this.value = HexString.toLong(value);
    }

    /**
     * Get the value of the DPID.
     *
     * @return the value of the DPID.
     */
    public long value() {
        return value;
    }

    /**
     * Convert the DPID value to a ':' separated hexadecimal string.
     *
     * @return the DPID value as a ':' separated hexadecimal string.
     */
    @Override
    public String toString() {
        return HexString.toHexString(this.value);
    }

    @Override
    public boolean equals(Object other) {
        if (!(other instanceof Dpid)) {
            return false;
        }

        Dpid otherDpid = (Dpid) other;

        return value == otherDpid.value;
    }

    @Override
    public int hashCode() {
        return Longs.hashCode(value);
    }
}