// This Source Code is in the Public Domain per: http://litesoft.org/License.txt
package org.litesoft.orsup.base;

import java.io.*;

import org.litesoft.core.typeutils.*;

/**
 * This class is a serializable, long-lived reference to a persistent object
 * <p/>
 * Other @ tags here...
 */
public class ObjectHandle implements Serializable,
                                     Comparable<ObjectHandle>
{
    static final long serialVersionUID = -112473324534691343L;

    public static final ObjectHandle[] EMPTY_ARRAY = new ObjectHandle[0];
    public static final char HANDLE_SEPARATOR = '\n';

    private PersistentObjectURL mPersistentObjectURL;
    private String mDisplayValue;

    public ObjectHandle( PersistentObjectURL pPersistentObjectURL, String pDisplayValue )
    {
        Objects.assertNotNull( "PersistentObjectURL", mPersistentObjectURL = pPersistentObjectURL );
        mDisplayValue = Strings.noEmpty( pDisplayValue );
    }

    public ObjectHandle( PersistentObjectURL pPersistentObjectURL )
    {
        this( pPersistentObjectURL, null );
    }

    protected boolean isDisplayValue()
    {
        return (mDisplayValue != null);
    }

    public PersistentObjectURL getPersistentObjectURL()
    {
        return mPersistentObjectURL;
    }

    /**
     * Print the handle with ID information
     *
     * @return Description of the Returned Value
     */
    public String printHandle()
    {
        String base = "Key" + " = " + mPersistentObjectURL;
        return isDisplayValue() ? base + ": " + mDisplayValue : base;
    }

    @Override
    public int compareTo( ObjectHandle pOther )
    {
        return this.toString().compareTo( pOther.toString() );
    }

    @Override
    public boolean equals( Object o )
    {
        return (this == o) || ((o instanceof ObjectHandle) && equals( (ObjectHandle) o ));
    }

    public boolean equals( ObjectHandle them )
    {
        return (this == them) || ((them != null) //
                                  && this.mPersistentObjectURL.equals( them.mPersistentObjectURL ) //
        );
    }

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

    @Override
    public String toString()
    {
        return isDisplayValue() ? mDisplayValue : printHandle();
    }

    public String getDisplayValue()
    {
        return isDisplayValue() ? mDisplayValue : getNoDisplayValue();
    }

    private String getNoDisplayValue()
    {
        return mPersistentObjectURL.toString();
    }

    public ObjectHandle setDisplayValue( String pDisplayValue )
    {
        mDisplayValue = (pDisplayValue == null) ? null : pDisplayValue.trim();
        return this;
    }

    public String getIdentifyingString()
    {
        return getNoDisplayValue();
    }

    public static String getIdentifyingString( ObjectHandle[] handles )
    {
        if ( Objects.isNullOrEmpty( handles ) )
        {
            return "";
        }
        StringBuilder ret = new StringBuilder();
        for ( ObjectHandle handle : handles )
        {
            ret.append( ObjectHandle.HANDLE_SEPARATOR );
            ret.append( handle.getIdentifyingString() );
        }
        return ret.toString().substring( 1 );
    }

    public static String getDisplayValue( ObjectHandle[] handles )
    {
        if ( Objects.isNullOrEmpty( handles ) )
        {
            return "";
        }
        StringBuilder ret = new StringBuilder();
        for ( ObjectHandle handle : handles )
        {
            ret.append( ObjectHandle.HANDLE_SEPARATOR );
            ret.append( handle.getDisplayValue() );
        }
        return ret.toString().substring( 1 );
    }
}