#!/usr/bin/perl

open(RANDOM, "/dev/urandom") or die;
read(RANDOM, $i, 4) or die;
close(RANDOM);

srand(unpack('I', $i));

%colours = (
		"red"		=> "1.0 0.3 0.3",
		"green"		=> "0.3 1.0 0.3",
		"blue"		=> "0.3 0.3 1.0",
		"orange"	=> "1.0 0.6 0.3",
		"purple"	=> "1.0 0.3 0.6",
		"cyan"		=> "0.3 0.6 1.0",
		"yellow"	=> "1.0 0.9 0.1"
	);

# dimensions in cm
$f_height = 12;
$f_width = 12;
$b_height = 11.8;
$b_width = 15;
$b_edge = 0.65;

# offsets
$b_ox = 2.0;
$b_oy = 1.5;

$f_ox = 2.0;
$f_oy = $b_oy + 1.5 + $b_height;

$margin = 0.5;

# fonts
$artist_font = "Helvetica";	$artist_size = 18;
$title_font = "Helvetica-Bold"; $title_size = 22;
$track_font = "Times-Roman";	$track_size = 11;
$spine_size = 11;

# input a file of information
sub input_file
{
	my $filename = shift(@_);
	my $track = 1;

	open(INPUT, "$filename");

	while(my $line = <INPUT>)
	{
		if ($line =~ /^[ \t]*track[ \t]*([0-9]*)[ \t]*=[ \t]*(.*)$/)
		{
			if ($1 ne undef)
			{
				$track = $1
			}

			$tracks[$track++] = $2;
		}
		elsif ($line =~ /^[ \t]*artist[ \t]*=[ \t]*(.*)$/)
		{
			$artist = $1;
		}
		elsif ($line =~ /^[ \t]*title[ \t]*=[ \t]*(.*)$/)
		{
			$title = $1;
		}
	}

	close(INPUT);
}

input_file($ARGV[0]);

print <<EOF;
Artist: $artist
 Title: $title

Track list:
EOF

for ($i = 1; $i < @tracks; $i++)
{
	if ($tracks[$i] ne undef)
	{
		printf("    %2d: %s\n", $i, $tracks[$i]);
	}
}

open(POSTSCRIPT, ">$ARGV[1]");

# draw the cover outlines

@cnames = keys(%colours);
$colour = $colours{@cnames[int rand() * @cnames]};

# conversion factor from cm to PostScript points
$conversion = 28.346457;

print POSTSCRIPT <<EOF;
%!PS-Adobe-2.0
%%Creator: mkcdcover (c) 1998 Chris Lightfoot
%%Pages: 1
$$EndComments
% unit conversions
/cm {28.346357 mul} def

% bands of color
0 setlinewidth
$colour setrgbcolor
newpath
$b_ox cm	$b_oy cm	moveto
$b_width cm	0		rlineto
0		$margin 2 mul cm
				rlineto
-$b_width cm	0		rlineto
closepath
fill

newpath
$f_ox cm	$f_oy cm	moveto
$f_width cm	0		rlineto
0		$margin 2 mul cm
				rlineto
-$f_width cm	0		rlineto
closepath
fill

% set colour to black for remainder of image
0 0 0 setrgbcolor

% the back cover of the cd
1 setlinewidth % outline in 1pt lines

% bounding box
newpath
$b_ox cm	$b_oy cm	moveto
$b_width cm	0		rlineto
0		$b_height cm	rlineto
-$b_width cm	0		rlineto
closepath
stroke

% edge lines
0.5 setlinewidth

newpath
$b_ox $b_edge add cm
		$b_oy cm	moveto
0		$b_height cm	rlineto
stroke

newpath
$b_ox $b_width add $b_edge sub cm
		$b_oy cm	moveto
0		$b_height cm	rlineto
stroke

% front cover of cd
1 setlinewidth

newpath
$f_ox cm	$f_oy cm	moveto
$f_width cm	0		rlineto
0		$f_height cm	rlineto
-$f_width cm	0		rlineto
closepath
stroke
EOF

# now put the text in
print POSTSCRIPT <<EOF;
/$artist_font findfont
$artist_size scalefont
setfont

% draw artist, title
% front
newpath
$f_ox $margin add cm
		$f_oy $f_height add $margin sub cm $artist_size sub
				moveto
($artist) show

/$title_font findfont
$title_size scalefont
setfont

newpath
$f_ox $margin add cm
		$f_oy $f_height add $margin sub cm $artist_size 2.25 mul sub
				moveto
($title) show

% back
/$artist_font findfont
$artist_size scalefont
setfont

newpath
$b_ox $b_edge add $margin add cm
		$b_oy $b_height add $margin sub cm $artist_size sub
				moveto
($artist) show

/$title_font findfont
$title_size scalefont
setfont

newpath
$b_ox $b_edge add $margin add cm
		$b_oy $b_height add $margin sub cm $artist_size 2.25 mul sub
				moveto
($title) show

% draw tracks
/$track_font findfont
$track_size scalefont
setfont
EOF

for ($i = 1; $i < @tracks; $i++)
{
	# we allow sparse tracklists
	if ($tracks[$i] ne undef)
	{
		print POSTSCRIPT <<EOF;
% track $i - $tracks[$i]
EOF

		$tracks[$i] =~ s/\(/\\\(/g;
		$tracks[$i] =~ s/\)/\\\)/g;

		print POSTSCRIPT <<EOF;
% front
newpath
$f_ox $margin add cm
		$f_oy $f_height add $margin sub cm $artist_size 2.25 mul sub
			$margin cm sub $i 1.25 mul $track_size mul sub
				moveto
($i) show

newpath
$f_ox $margin 4 mul add cm
		$f_oy $f_height add $margin sub cm $artist_size 2.25 mul sub
			$margin cm sub $i 1.25 mul $track_size mul sub
				moveto
($tracks[$i]) show

% back
newpath
$b_ox $b_edge add $margin add cm
		$b_oy $b_height add $margin sub cm $artist_size 2.25 mul sub
			$margin cm sub $i 1.25 mul $track_size mul sub
				moveto
($i) show

newpath
$b_ox $b_edge add $margin 4 mul add cm
		$b_oy $b_height add $margin sub cm $artist_size 2.25 mul sub
			$margin cm sub $i 1.25 mul $track_size mul sub
				moveto
($tracks[$i]) show
EOF
	}
}

# print the spine text
print POSTSCRIPT <<EOF;
/$artist_font findfont
$spine_size scalefont
setfont

gsave

% left
$b_ox cm $b_edge cm $spine_size sub 1.6 div add
	$b_oy $b_height add $margin sub cm moveto
-90 rotate
($artist) show

/$title_font findfont
$spine_size scalefont
setfont

(  $title) show

grestore

% right  %$b_edge cm sub $spine_size sub 1.6 div add
$b_ox $b_width add $b_edge sub cm $b_edge cm $spine_size sub 1.6 div add
	$b_oy $b_height add $margin sub cm moveto
-90 rotate
($artist) show

/$title_font findfont
$spine_size scalefont
setfont

(  $title) show

EOF

print POSTSCRIPT <<EOF;
showpage
EOF

close(POSTSCRIPT);