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use PDL::LiteF;
use PDL::IO::Pnm;
use PDL::Dbg;
use File::Temp qw(tempdir);
use File::Spec;

# we need tests with index shuffling once vaffines are fixed
use Test::More;

sub tapprox {
	my($a,$b,$mdiff) = @_;
	$mdiff = 0.01 unless defined($mdiff);
	$c = abs($a-$b);
	$d = max($c);
	$d < $mdiff;
}

sub rpnm_unlink {
  my $file = shift;
  my $pdl = rpnm($file);
  unlink $file;
  return $pdl;
}

$PDL::debug = $PDL::debug = 0;
$PDL::debug = 1 if defined($ARGV[0]) && $ARGV[0] =~ /-v/;

#              [FORMAT, extension, ushort-divisor,
#               only RGB/no RGB/any (1/-1/0), mxdiff]
#  no test of PCX format because seems to be severely brain damaged
@formats = ( ['PNM', 'pnm',  1, 0, 0.01],
	     ['GIF', 'gif',256, 0, 0.01],
	     ['TIFF','tif',  1, 0, 0.01],);

## GIF doesn't handle 16-bit so it has 2 * 2 tests
## while the other formats have 2 * 3 tests each
## $ntests = 2 * 3 * @formats ;
plan tests => 16;

$im1 = pdl([[0,65535,0], [256,256,256], [65535,256,65535]])->ushort;
$im2 = byte($im1/256);

# make the resulting file at least 12 byte long
# otherwise we run into a problem when reading the magic (Fix!)
$im3 = byte [[0,0,255,255,12,13],[1,4,5,6,11,124],
	     [100,0,0,0,10,10],[2,1,0,1,0,14],[2,1,0,1,0,14],
	     [2,1,0,1,0,14]];

if ($PDL::debug) {
  note $im1;
  $im1->px;
  note $im2;
  $im2->px;
  note $im3>0;
  $im3->px;
}

# for some reason the pnmtotiff converter coredumps when trying
# to do the conversion for the ushort data, haven't yet tried to
# figure out why
$n = 1;
my $tmpdir = tempdir( CLEANUP => 1 );
sub tmpfile { File::Spec->catfile($tmpdir, $_[0]); }
for $raw (0,1) {
  foreach $form (@formats) {
    note "testing $form->[0] format **\n";

    my $tushort = tmpfile("tushort.$form->[0]");
    my $tbyte = tmpfile("tbyte.$form->[0]");
    my $tbin = tmpfile("tbin.$form->[0]");
    wpnm ($im1,$tushort,'PGM',$raw)
      unless $form->[0] eq 'GIF';
    wpnm ($im2,$tbyte,'PGM',$raw);
    wpnm ($im3,$tbin,'PBM',$raw);
    $in1 = rpnm_unlink($tushort) unless $form->[0] eq 'GIF';
    $in2 = rpnm_unlink($tbyte);
    $in3 = rpnm_unlink($tbin);

    if ($form->[0] ne 'GIF') {
      $scale = ($form->[3] ? $im1->dummy(0,3) : $im1);
      $comp = $scale / $form->[2];
      ok(tapprox($comp,$in1,$form->[4]));
    }
    $comp = ($form->[3] ? $im2->dummy(0,3) : $im2);
    ok(tapprox($comp,$in2));
    $comp = ($form->[3] ? ($im3->dummy(0,3)>0)*255 : ($im3 > 0));
    $comp = $comp->ushort*65535 if $form->[0] eq 'SGI'; # yet another format quirk
    ok(tapprox($comp,$in3));

    if ($PDL::debug) {
      note $in1->px unless $form->[0] eq 'TIFF';
      note $in2->px;
      note $in3->px;
    }
  }
}