/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2016, Open Source Geospatial Foundation (OSGeo)
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License as published by the Free Software Foundation;
 *    version 2.1 of the License.
 *
 *    This library is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *    Lesser General Public License for more details.
 */
package org.geotools.process.raster;

import org.geotools.coverage.CoverageFactoryFinder;
import org.geotools.coverage.grid.GridCoverage2D;
import org.geotools.coverage.grid.GridCoverageFactory;
import org.geotools.factory.GeoTools;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.referencing.crs.DefaultGeographicCRS;
import org.junit.Before;
import org.junit.Test;

import java.awt.image.Raster;

import static org.junit.Assert.assertEquals;

public class NormalizeCoverageProcessTest {

    GridCoverageFactory covFactory;
    
    @Before
    public void setUp() {
        covFactory = CoverageFactoryFinder.getGridCoverageFactory(GeoTools.getDefaultHints());
    }

    @Test
    public void test() throws Exception {
        float[][] grid = new float[][] {
            {1,2,3,4},
            {5,6,8,9},
            {10,11,12,13},
            {14,15,16,17},
        };

        GridCoverage2D cov = covFactory.create("test", grid, new ReferencedEnvelope(0,10,0,10, DefaultGeographicCRS.WGS84));
        NormalizeCoverageProcess p = new NormalizeCoverageProcess();
        GridCoverage2D norm = p.execute(cov);

        float[] data = data(norm);
        for (int i = 0; i < data.length; i++) {
            assertEquals(grid[i/grid.length][i%grid.length]/17f, data[i], 1E-9);
        }
    }

    @Test
    public void testZeroCoverage() throws Exception {
        float[][] grid = new float[][] {
            {0,0},
            {0,0},
        };

        GridCoverage2D cov = covFactory.create("test", grid, new ReferencedEnvelope(0,10,0,10, DefaultGeographicCRS.WGS84));
        NormalizeCoverageProcess p = new NormalizeCoverageProcess();
        GridCoverage2D norm = p.execute(cov);

        float[] data = data(norm);
        for (int i = 0; i < data.length; i++) {
            assertEquals(0f, data[i], 1E-9);
        }
    }
    float[] data(GridCoverage2D cov) {
        Raster data = cov.getRenderedImage().getData();
        int w = data.getWidth();
        int h = data.getHeight();

        float[] grid = new float[w*h];
        data.getDataElements(0, 0, w, h, grid);

        return grid;
    }
}