#!/usr/bin/env pytest
###############################################################################
# $Id: dither.py 30250f784292af8d1f0ae95625b06ac482885d86 2018-12-14 10:16:24 +1300 Craig de Stigter $
#
# Project:  GDAL/OGR Test Suite
# Purpose:  Test gdal.ComputeMedianCutPCT() and gdal.DitherRGB2PCT()
# Author:   Frank Warmerdam <warmerdam@pobox.com>
#
###############################################################################
# Copyright (c) 2008, Frank Warmerdam <warmerdam@pobox.com>
# Copyright (c) 2008-2009, Even Rouault <even dot rouault at mines-paris dot org>
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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# DEALINGS IN THE SOFTWARE.
###############################################################################




from osgeo import gdal
import pytest

###############################################################################
# Test


def test_dither_1():

    drv = gdal.GetDriverByName('GTiff')

    src_ds = gdal.Open('../gdrivers/data/rgbsmall.tif')
    r_band = src_ds.GetRasterBand(1)
    g_band = src_ds.GetRasterBand(2)
    b_band = src_ds.GetRasterBand(3)

    dst_ds = drv.Create('tmp/rgbsmall.tif', src_ds.RasterXSize,
                        src_ds.RasterYSize, 1, gdal.GDT_Byte)
    dst_band = dst_ds.GetRasterBand(1)

    ct = gdal.ColorTable()

    nColors = 8

    gdal.ComputeMedianCutPCT(r_band, g_band, b_band, nColors, ct)

    dst_band.SetRasterColorTable(ct)

    gdal.DitherRGB2PCT(r_band, g_band, b_band, dst_band, ct)

    cs_expected = 8803
    cs = dst_band.Checksum()
    dst_band = None
    dst_ds = None

    assert ct.GetCount() == nColors, 'color table size wrong'

    ref_ct = [(36, 48, 32, 255), (92, 120, 20, 255), (88, 96, 20, 255), (92, 132, 56, 255),
              (0, 0, 0, 255), (96, 152, 24, 255), (60, 112, 32, 255), (164, 164, 108, 255)]

    for i in range(nColors):
        ct_data = ct.GetColorEntry(i)
        ref_data = ref_ct[i]

        for j in range(4):

            if ct_data[j] != ref_data[j]:
                for k in range(nColors):
                    print(ct.GetColorEntry(k))
                    print(ref_ct[k])
                pytest.fail('color table mismatch')

    if cs == cs_expected or gdal.GetConfigOption('CPL_DEBUG', 'OFF') != 'ON':
        drv.Delete('tmp/rgbsmall.tif')

    if cs != cs_expected:
        print('Got: ', cs)
        pytest.fail('got wrong checksum')

    



