import java.io.File;
import java.io.IOException;
import java.nio.file.Paths;
import java.util.Collection;
import javax.imageio.ImageIO;
import java.awt.image.ImagingOpException;
import org.apache.sis.storage.Resource;
import org.apache.sis.storage.Aggregate;
import org.apache.sis.storage.DataStore;
import org.apache.sis.storage.DataStores;
import org.apache.sis.storage.DataStoreException;
import org.apache.sis.storage.GridCoverageResource;
import org.apache.sis.coverage.grid.GridCoverage;
import org.apache.sis.coverage.grid.GridCoverageProcessor;
import org.apache.sis.image.Interpolation;
import org.apache.sis.referencing.CRS;
import org.opengis.referencing.operation.TransformException;
import org.opengis.util.FactoryException;

public class ResampleAndSaveRaster {
    /**
     * Demo entry point.
     *
     * @param  args  ignored.
     * @throws DataStoreException if an error occurred while reading the raster.
     * @throws FactoryException   if an error occurred while creating the Coordinate Reference System (CRS).
     * @throws TransformException if an error occurred while transforming coordinates to the target CRS.
     * @throws ImagingOpException unchecked exception thrown if an error occurred while resampling a tile.
     */
    public static void main(String[] args) throws DataStoreException, FactoryException, TransformException, IOException {
        try (DataStore store = DataStores.open(Paths.get("Airport.tiff"))) {
            /*
             * This data store is an aggregate because a GeoTIFF file may contain many images.
             * Not all data stores are aggregate, so the following casts do not apply to all.
             * For this example, we know that the file is GeoTIFF and we take the first image.
             */
            Collection<? extends Resource> allImages = ((Aggregate) store).components();
            GridCoverageResource firstImage = (GridCoverageResource) allImages.iterator().next();
            /*
             * The following code read fully the specified resource.
             * For reading only a subset, or for handling data bigger
             * than memory, see "How to..." in Apache SIS web site.
             */
            GridCoverage data = firstImage.read(null, null);
            System.out.printf("Information about the selected image:%n%s%n", data);
            /*
             * Reproject to "WGS 84 / World Mercator" (EPSG::3395) using bilinear interpolation.
             * This example lets Apache SIS choose the output grid size and resolution.
             * But it is possible to specify those aspects if desired.
             */
            var processor = new GridCoverageProcessor();
            processor.setInterpolation(Interpolation.BILINEAR);
            data = processor.resample(data, CRS.forCode("EPSG::3395"));
            System.out.printf("Information about the image after reprojection:%n%s%n", data);
            /*
             * TODO: Apache SIS is missing a `DataStores.write(…)` convenience method.
             * Writing a TIFF World File is possible but requires use of internal API.
             * A public convenience method will be added in next version.
             * For now we use Java I/O API.
             */
            ImageIO.write(data.render(null), "png", new File("test.png"));
        }
    }
}