osg::Image*
CompositeTileSource::createImage( const TileKey& key, ProgressCallback* progress )
{
    ImageMixVector images;
    images.reserve( _options._components.size() );

    for(CompositeTileSourceOptions::ComponentVector::const_iterator i = _options._components.begin();
        i != _options._components.end();
        ++i )
    {
        if ( progress && progress->isCanceled() )
            return 0L;

        // check that this source is within the level bounds:
        if (i->_imageLayerOptions->minLevel().value() > key.getLevelOfDetail() ||
            i->_imageLayerOptions->maxLevel().value() < key.getLevelOfDetail() )
        {
            continue;
        }

        TileSource* source = i->_tileSourceInstance->get();
        if ( source )
        {
            if ( !source->getBlacklist()->contains( key.getTileId() ) )
            {
                //Only try to get data if the source actually has data
                if ( source->hasData( key ) )
                {
                    ImageOpacityPair imagePair(
                        source->createImage( key, _preCacheOp.get(), progress ),
                        1.0f );

                    //If the image is not valid and the progress was not cancelled, blacklist
                    if (!imagePair.first.valid() && (!progress || !progress->isCanceled()))
                    {
                        //Add the tile to the blacklist
                        OE_DEBUG << LC << "Adding tile " << key.str() << " to the blacklist" << std::endl;
                        source->getBlacklist()->add( key.getTileId() );
                    }

                    if ( imagePair.first.valid() )
                    {
                        // check for opacity:
                        imagePair.second = i->_imageLayerOptions.isSet() ? i->_imageLayerOptions->opacity().value() : 1.0f;

                        images.push_back( imagePair );
                    }
                }
                else
                {
                    OE_DEBUG << LC << "Source has no data at " << key.str() << std::endl;
                }
            }
            else
            {
                OE_DEBUG << LC << "Tile " << key.str() << " is blacklisted, not checking" << std::endl;
            }
        }
    }

    if ( progress && progress->isCanceled() )
    {
        return 0L;
    }
    else if ( images.size() == 0 )
    {
        return 0L;
    }
    else if ( images.size() == 1 )
    {
        return images[0].first.release();
    }
    else
    {
        osg::Image* result = new osg::Image( *images[0].first.get() );
        for( unsigned int i=1; i<images.size(); ++i )
        {
            ImageOpacityPair& pair = images[i];
            if ( pair.first.valid() )
            {
                ImageUtils::mix( result, pair.first.get(), pair.second );
            }
        }
        return result;
    }
}
osg::Image*
CompositeTileSource::createImage(const TileKey&    key,
                                 ProgressCallback* progress )
{
    ImageMixVector images;
    images.reserve( _options._components.size() );

    for(CompositeTileSourceOptions::ComponentVector::const_iterator i = _options._components.begin();
        i != _options._components.end();
        ++i )
    {
        if ( progress && progress->isCanceled() )
            return 0L;

        ImageInfo imageInfo;
        imageInfo.dataInExtents = false;



        TileSource* source = i->_tileSourceInstance.get();
        if ( source )
        {
            //TODO:  This duplicates code in ImageLayer::isKeyValid.  Maybe should move that to TileSource::isKeyValid instead
            int minLevel = 0;
            int maxLevel = INT_MAX;
            if (i->_imageLayerOptions->minLevel().isSet())
            {
                minLevel = i->_imageLayerOptions->minLevel().value();
            }
            else if (i->_imageLayerOptions->minResolution().isSet())
            {
                minLevel = source->getProfile()->getLevelOfDetailForHorizResolution( 
                    i->_imageLayerOptions->minResolution().value(), 
                    source->getPixelsPerTile());
            }

            if (i->_imageLayerOptions->maxLevel().isSet())
            {
                maxLevel = i->_imageLayerOptions->maxLevel().value();
            }
            else if (i->_imageLayerOptions->maxResolution().isSet())
            {
                maxLevel = source->getProfile()->getLevelOfDetailForHorizResolution( 
                    i->_imageLayerOptions->maxResolution().value(), 
                    source->getPixelsPerTile());
            }

            // check that this source is within the level bounds:
            if (minLevel > (int)key.getLevelOfDetail() ||
                maxLevel < (int)key.getLevelOfDetail() )
            {
                continue;
            }
            
                //Only try to get data if the source actually has data                
                if (source->hasDataInExtent( key.getExtent() ) )
                {
                    //We have data within these extents
                    imageInfo.dataInExtents = true;

                    if ( !source->getBlacklist()->contains( key.getTileId() ) )
                    {                        
                        osg::ref_ptr< ImageLayerPreCacheOperation > preCacheOp;
                        if ( i->_imageLayerOptions.isSet() )
                        {
                            preCacheOp = new ImageLayerPreCacheOperation();
                            preCacheOp->_processor.init( i->_imageLayerOptions.value(), _dbOptions.get(), true );                        
                        }

                        imageInfo.image = source->createImage( key, preCacheOp.get(), progress );
                        imageInfo.opacity = 1.0f;

                        //If the image is not valid and the progress was not cancelled, blacklist
                        if (!imageInfo.image.valid() && (!progress || !progress->isCanceled()))
                        {
                            //Add the tile to the blacklist
                            OE_DEBUG << LC << "Adding tile " << key.str() << " to the blacklist" << std::endl;
                            source->getBlacklist()->add( key.getTileId() );
                        }
                        imageInfo.opacity = i->_imageLayerOptions.isSet() ? i->_imageLayerOptions->opacity().value() : 1.0f;
                    }
                }
                else
                {
                    OE_DEBUG << LC << "Source has no data at " << key.str() << std::endl;
                }
        }

        //Add the ImageInfo to the list
        images.push_back( imageInfo );
    }

    unsigned numValidImages = 0;
    osg::Vec2s textureSize;
    for (unsigned int i = 0; i < images.size(); i++)
    {
        ImageInfo& info = images[i];
        if (info.image.valid())
        {
            if (numValidImages == 0)
            {
                textureSize.set( info.image->s(), info.image->t());
            }
            numValidImages++;        
        }
    }

    //Try to fallback on any empty images if we have some valid images but not valid images for ALL layers
    if (numValidImages > 0 && numValidImages < images.size())
    {        
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& info = images[i];
            if (!info.image.valid() && info.dataInExtents)
            {                                
                TileKey parentKey = key.createParentKey();

                TileSource* source = _options._components[i]._tileSourceInstance;
                if (source)
                {                 
                    osg::ref_ptr< ImageLayerPreCacheOperation > preCacheOp;
                    if ( _options._components[i]._imageLayerOptions.isSet() )
                    {
                        preCacheOp = new ImageLayerPreCacheOperation();
                        preCacheOp->_processor.init( _options._components[i]._imageLayerOptions.value(), _dbOptions.get(), true );                        
                    }                

                    osg::ref_ptr< osg::Image > image;
                    while (!image.valid() && parentKey.valid())
                    {                        
                        image = source->createImage( parentKey, preCacheOp.get(), progress );
                        if (image.valid())
                        {                     
                            break;
                        }
                        parentKey = parentKey.createParentKey();
                    }     

                    if (image.valid())
                    {
                        //We got an image, but now we need to crop it to match the incoming key's extents
                        GeoImage geoImage( image.get(), parentKey.getExtent());
                        GeoImage cropped = geoImage.crop( key.getExtent(), true, textureSize.x(), textureSize.y(), *source->_options.bilinearReprojection());
                        image = cropped.getImage();
                    }

                    info.image = image.get();
                }
            }
        }
    }

    //Recompute the number of valid images
    numValidImages = 0;
    for (unsigned int i = 0; i < images.size(); i++)
    {
        ImageInfo& info = images[i];
        if (info.image.valid()) numValidImages++;        
    }

    if ( progress && progress->isCanceled() )
    {
        return 0L;
    }
    else if ( numValidImages == 0 )
    {
        return 0L;
    }
    else if ( numValidImages == 1 )
    {
        //We only have one valid image, so just return it and don't bother with compositing
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& info = images[i];
            if (info.image.valid())
                return info.image.release();
        }
        return 0L;
    }
    else
    {
        osg::Image* result = 0;
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& imageInfo = images[i];
            if (!result)
            {
                if (imageInfo.image.valid())
                {
                    result = new osg::Image( *imageInfo.image.get());
                }
            }
            else
            {
                if (imageInfo.image.valid())
                {
                    ImageUtils::mix( result, imageInfo.image, imageInfo.opacity );
                }
            }            
        }        
        return result;
    }
}
osg::Image*
CompositeTileSource::createImage(const TileKey&    key,
                                 ProgressCallback* progress )
{    
    ImageMixVector images;
    images.reserve(_imageLayers.size());

    // Try to get an image from each of the layers for the given key.
    for (ImageLayerVector::const_iterator itr = _imageLayers.begin(); itr != _imageLayers.end(); ++itr)
    {
        ImageLayer* layer = itr->get();
        ImageInfo imageInfo;
        imageInfo.dataInExtents = layer->getTileSource()->hasDataInExtent( key.getExtent() );
        imageInfo.opacity = layer->getOpacity();

        if (imageInfo.dataInExtents)
        {
            GeoImage image = layer->createImage(key, progress);
            if (image.valid())
            {
                imageInfo.image = image.getImage();
            }

            // If the progress got cancelled or it needs a retry then return NULL to prevent this tile from being built and cached with incomplete or partial data.
            if (progress && (progress->isCanceled() || progress->needsRetry()))
            {
                OE_DEBUG << LC << " createImage was cancelled or needs retry for " << key.str() << std::endl;
                return 0L;
            }
        }

        images.push_back(imageInfo);
    }

    // Determine the output texture size to use based on the image that were creatd.
    unsigned numValidImages = 0;
    osg::Vec2s textureSize;
    for (unsigned int i = 0; i < images.size(); i++)
    {
        ImageInfo& info = images[i];
        if (info.image.valid())
        {
            if (numValidImages == 0)
            {
                textureSize.set( info.image->s(), info.image->t());
            }
            numValidImages++;        
        }
    } 

    // Create fallback images if we have some valid data but not for all the layers
    if (numValidImages > 0 && numValidImages < images.size())
    {
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& info = images[i];
            ImageLayer* layer = _imageLayers[i].get();
            if (!info.image.valid() && info.dataInExtents)
            {                      
                TileKey parentKey = key.createParentKey();

                GeoImage image;
                while (!image.valid() && parentKey.valid())
                {
                    image = layer->createImage(parentKey, progress);
                    if (image.valid())
                    {
                        break;
                    }

                    // If the progress got cancelled or it needs a retry then return NULL to prevent this tile from being built and cached with incomplete or partial data.
                    if (progress && (progress->isCanceled() || progress->needsRetry()))
                    {
                        OE_DEBUG << LC << " createImage was cancelled or needs retry for " << key.str() << std::endl;
                        return 0L;
                    }

                    parentKey = parentKey.createParentKey();
                }

                if (image.valid())
                {                                        
                    // TODO:  Bilinear options?
                    bool bilinear = layer->isCoverage() ? false : true;
                    GeoImage cropped = image.crop( key.getExtent(), true, textureSize.x(), textureSize.y(), bilinear);
                    info.image = cropped.getImage();
                }                    
            }
        }
    }

    // Now finally create the output image.
    //Recompute the number of valid images
    numValidImages = 0;
    for (unsigned int i = 0; i < images.size(); i++)
    {
        ImageInfo& info = images[i];
        if (info.image.valid()) numValidImages++;        
    }    

    if ( progress && progress->isCanceled() )
    {
        return 0L;
    }
    else if ( numValidImages == 0 )
    {
        return 0L;
    }
    else if ( numValidImages == 1 )
    {
        //We only have one valid image, so just return it and don't bother with compositing
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& info = images[i];
            if (info.image.valid())
                return info.image.release();
        }
        return 0L;
    }
    else
    {
        osg::Image* result = 0;
        for (unsigned int i = 0; i < images.size(); i++)
        {
            ImageInfo& imageInfo = images[i];
            if (!result)
            {
                if (imageInfo.image.valid())
                {
                    result = new osg::Image( *imageInfo.image.get());
                }
            }
            else
            {
                if (imageInfo.image.valid())
                {
                    ImageUtils::mix( result, imageInfo.image.get(), imageInfo.opacity );
                }
            }            
        }        
        return result;
    }



}
osg::Image*
CompositeTileSource::createImage( const TileKey& key, ProgressCallback* progress )
{
    ImageMixVector images;
    images.reserve( _options._components.size() );

    for(CompositeTileSourceOptions::ComponentVector::const_iterator i = _options._components.begin();
            i != _options._components.end();
            ++i )
    {
        if ( progress && progress->isCanceled() )
            return 0L;

        TileSource* source = i->_tileSourceInstance->get();
        if ( source )
        {

            //TODO:  This duplicates code in ImageLayer::isKeyValid.  Maybe should move that to TileSource::isKeyValid instead
            int minLevel = 0;
            int maxLevel = INT_MAX;
            if (i->_imageLayerOptions->minLevel().isSet())
            {
                minLevel = i->_imageLayerOptions->minLevel().value();
            }
            else if (i->_imageLayerOptions->minLevelResolution().isSet())
            {
                minLevel = source->getProfile()->getLevelOfDetailForHorizResolution( i->_imageLayerOptions->minLevelResolution().value(), source->getPixelsPerTile());
            }

            if (i->_imageLayerOptions->maxLevel().isSet())
            {
                maxLevel = i->_imageLayerOptions->maxLevel().value();
            }
            else if (i->_imageLayerOptions->maxLevelResolution().isSet())
            {
                maxLevel = source->getProfile()->getLevelOfDetailForHorizResolution( i->_imageLayerOptions->maxLevelResolution().value(), source->getPixelsPerTile());
            }




            // check that this source is within the level bounds:
            if (minLevel > key.getLevelOfDetail() ||
                    maxLevel < key.getLevelOfDetail() )
            {
                continue;
            }





            if ( !source->getBlacklist()->contains( key.getTileId() ) )
            {
                //Only try to get data if the source actually has data
                if ( source->hasData( key ) )
                {
                    osg::ref_ptr< ImageLayerPreCacheOperation > preCacheOp;
                    if ( i->_imageLayerOptions.isSet() )
                    {
                        preCacheOp = new ImageLayerPreCacheOperation();
                        preCacheOp->_processor.init( i->_imageLayerOptions.value(), true );
                    }



                    ImageOpacityPair imagePair(
                        source->createImage( key, preCacheOp.get(), progress ),
                        1.0f );

                    //If the image is not valid and the progress was not cancelled, blacklist
                    if (!imagePair.first.valid() && (!progress || !progress->isCanceled()))
                    {
                        //Add the tile to the blacklist
                        OE_DEBUG << LC << "Adding tile " << key.str() << " to the blacklist" << std::endl;
                        source->getBlacklist()->add( key.getTileId() );
                    }

                    if ( imagePair.first.valid() )
                    {
                        // check for opacity:
                        imagePair.second = i->_imageLayerOptions.isSet() ? i->_imageLayerOptions->opacity().value() : 1.0f;

                        images.push_back( imagePair );
                    }
                }
                else
                {
                    OE_DEBUG << LC << "Source has no data at " << key.str() << std::endl;
                }
            }
            else
            {
                OE_DEBUG << LC << "Tile " << key.str() << " is blacklisted, not checking" << std::endl;
            }
        }
    }

    if ( progress && progress->isCanceled() )
    {
        return 0L;
    }
    else if ( images.size() == 0 )
    {
        return 0L;
    }
    else if ( images.size() == 1 )
    {
        return images[0].first.release();
    }
    else
    {
        osg::Image* result = new osg::Image( *images[0].first.get() );
        for( unsigned int i=1; i<images.size(); ++i )
        {
            ImageOpacityPair& pair = images[i];
            if ( pair.first.valid() )
            {
                ImageUtils::mix( result, pair.first.get(), pair.second );
            }
        }
        return result;
    }
}