#!/usr/bin/perl

if ($#ARGV != 3)
{
	die "usage: pnm2cif <pnm-image-filename> <cell-name> <scalar> <layer-name>"
}

$inFile = $ARGV[0];
$cellName = $ARGV[1];
$scalar = $ARGV[2];
$layerName = $ARGV[3];
$outFile = $inFile;
$outFile =~ s/\.pnm$/.cif/;

open (INFILE, $inFile) or die "Can't open input file $inFile\n";
open (OUTFILE, ">$outFile") or die "Can't open output file $outFile\n";

<INFILE>;
if ($_ != "P3") { die "Not an ASCII PNM\n"; }

skipcomments: while (<INFILE>)
{
	if (not $_ =~ /^#/) { last skipcomments; }
}

<INFILE>;
($width,$height) = /(\d+)\s+(\d+)/;

$x = 0;
$y = 0;
$startBar = -1;

print OUTFILE "DS 1 1 1;\n";
print OUTFILE "9 $cellName;\n";
print OUTFILE "L $layerName;\n";

while ($x < $width and $y < $height)
{
	<INFILE>; <INFILE>;
	$line = <INFILE>;

	if ($startBar != -1)
	{
		if ($line == 255) # End a bar
		{
			completeBar ();
			$startBar = -1;
		}
	} else {
		if ($line == 0) # Start a bar
		{
			$startBar = $x;
		}
	}

	$x ++;
	if ($x == $width)
	{
		if ($startBar != -1) { completeBar (); }
		$x = 0;
		$y ++;
	}
}

print OUTFILE "DF;\nE;\n";

sub scale
{
	$in = shift;

	$in * $scalar;
}

sub completeBar
{
	print OUTFILE "B ", scale ($x - $startBar), " ",
		scale (1), " ",
		scale (($x + $startBar) / 2), " ",
		scale ($height) - scale ($y + 0.5), ";\n";
}