/*
 * Copyright (c) 2016, Metron, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of Metron, Inc. nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL METRON, INC. BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.metsci.glimpse.context;

import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;

import com.metsci.glimpse.canvas.GlimpseCanvas;

/**
 *
 * @author ulman
 * @see GlimpseTargetStack
 */
public class GlimpseTargetStackImpl implements GlimpseTargetStack
{
    private final LinkedList<GlimpseTarget> targetStack;
    private final List<GlimpseTarget> targetStackUnmod;

    private final LinkedList<GlimpseBounds> boundStack;
    private final List<GlimpseBounds> boundStackUnmod;

    public GlimpseTargetStackImpl( GlimpseTarget... targets )
    {
        this.targetStack = new LinkedList<GlimpseTarget>( );
        this.targetStackUnmod = Collections.unmodifiableList( targetStack );

        this.boundStack = new LinkedList<GlimpseBounds>( );
        this.boundStackUnmod = Collections.unmodifiableList( boundStack );

        for ( GlimpseTarget target : targets )
        {
            this.push( target );
        }
    }

    public GlimpseTargetStackImpl( GlimpseCanvas canvas )
    {
        this.targetStack = new LinkedList<GlimpseTarget>( );
        this.targetStackUnmod = Collections.unmodifiableList( targetStack );

        this.boundStack = new LinkedList<GlimpseBounds>( );
        this.boundStackUnmod = Collections.unmodifiableList( boundStack );

        this.push( canvas, canvas.getTargetBounds( ) );
    }

    @Override
    public GlimpseTargetStack push( GlimpseTarget target, GlimpseBounds bounds )
    {
        this.targetStack.push( target );
        this.boundStack.push( bounds );
        return this;
    }

    @Override
    public GlimpseTargetStack push( GlimpseTarget target )
    {
        // since no bounds were specified, use the currently
        // cached bounds for the target under this context if
        // they exist or simply use dummy bounds otherwise
        GlimpseBounds bounds = target.getTargetBounds( this );
        if ( bounds == null )
        {
            bounds = new GlimpseBounds( 0, 0, 0, 0 );
        }

        this.targetStack.push( target );
        this.boundStack.push( bounds );
        return this;
    }

    @Override
    public GlimpseTargetStack push( GlimpseTargetStack stack )
    {
        List<GlimpseTarget> targetList = stack.getTargetList( );
        ListIterator<GlimpseTarget> targetIter = targetList.listIterator( targetList.size( ) );

        List<GlimpseBounds> boundsList = stack.getBoundsList( );
        ListIterator<GlimpseBounds> boundsIter = boundsList.listIterator( boundsList.size( ) );

        while ( targetIter.hasPrevious( ) )
        {
            push( targetIter.previous( ), boundsIter.previous( ) );
        }

        return this;
    }

    @Override
    public GlimpseTargetStack pop( )
    {
        this.targetStack.pop( );
        this.boundStack.pop( );
        return this;
    }

    @Override
    public GlimpseTarget getTarget( )
    {
        return this.targetStack.peek( );
    }

    @Override
    public GlimpseBounds getBounds( )
    {
        return this.boundStack.peek( );
    }

    @Override
    public List<GlimpseTarget> getTargetList( )
    {
        return targetStackUnmod;
    }

    @Override
    public List<GlimpseBounds> getBoundsList( )
    {
        return boundStackUnmod;
    }

    @Override
    public int getSize( )
    {
        return targetStack.size( );
    }

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

    @Override
    public boolean equals( Object obj )
    {
        if ( this == obj ) return true;
        if ( obj == null ) return false;
        if ( getClass( ) != obj.getClass( ) ) return false;

        GlimpseTargetStackImpl other = ( GlimpseTargetStackImpl ) obj;
        if ( targetStack == null )
        {
            if ( other.targetStack != null ) return false;
        }
        else if ( !targetStack.equals( other.targetStack ) )
        {
            return false;
        }

        return true;
    }

    @Override
    public String toString( )
    {
        StringBuilder b = new StringBuilder( );

        b.append( "[" );

        Iterator<GlimpseTarget> targetIter = targetStack.iterator( );
        Iterator<GlimpseBounds> boundsIter = boundStack.iterator( );

        while ( targetIter.hasNext( ) )
        {
            GlimpseTarget target = targetIter.next( );
            GlimpseBounds bounds = boundsIter.next( );

            b.append( String.format( "[%s,%s],", target, bounds ) );
        }

        if ( targetStack.isEmpty( ) )
        {
            // Drop the trailing comma
            b.setLength( b.length( ) - 1 );
        }

        b.append( "]" );

        return b.toString( );
    }
}