#!/usr/bin/perl -w

# Print "DRAFT" string in background of every page.
# DRAFT string can be changed on the command line.
# String can be a single word or a quoted string.

# Input is a PostScript file.
# Output is another PostScript named the same as the input file.

$usage = "usage: $0 [draft_string] <filename>\n";

@ARGV || die "$usage\n"; 
# Check that an argument was given

$number_of_args = @ARGV; 

if($number_of_args == 1){    
    $filename = shift(@ARGV);  
    if(-e $filename){             # Check if $filename exists;
	$draft_string = "DRAFT";  # if not, exit
    } else {                     
	print "$0: File $filename not found.\n";	
	exit 1;
    }
}

if($number_of_args == 2){
    $draft_string = shift(@ARGV);  # Get draft string
    $filename = shift(@ARGV);      # Get file name
    if(!(-e $filename)){   # If file does not exist, exit
	print "$0: File $filename not found.\n";	
	exit 1;
    }
}

open (IN,"<$filename") || die "$0: failed to open input file";
open (OUT,">ps_tmp") || die "$0: failed to open output file";

# Print all lines to OUT until "AcccurateScreens" is located
while(<IN>){     
    if(!/AcccurateScreens/){ 
	print OUT;
    } else {
	last;
    }
}
print OUT; # print line containing AcccurateScreens to file
           # YES--Acccurate is misspelled in the FM-generated PostScript
           # for now

# Insert PostScript code for printing the watermark
print OUT "\n";
print OUT "% Prelude to show a draft string on every page.\n";
print OUT "($draft_string)\n";
print OUT "/DRAFTDICT 10 dict def\n";
print OUT "DRAFTDICT begin\n";
print OUT "/DRAFTSTRING exch def\n";
print OUT "/bd /Helvetica-Bold findfont def\n";
print OUT "/od bd maxlength 1 add dict def\n";
print OUT "    bd {exch dup /FID ne {exch od 3 1 roll put} {pop pop} ifelse} forall\n";
print OUT "od /FontName /Outline0 put od /PaintType 2 put od /StrokeWidth 0 put\n";
print OUT "/Outline0 od definefont pop\n";
print OUT "    /DRAFT { gsave\n";
print OUT "    [1 3] 0 setdash 0.2 setgray\n";
print OUT "     initmatrix\n";
print OUT "    /Outline0 findfont setfont\n";
print OUT "    DRAFTSTRING dup stringwidth pop 8.875 exch div dup 72 mul dup scale\n";
print OUT "    52.3 rotate 2.5 exch div -.35 translate\n";
print OUT "    0 0 moveto show\n";
print OUT "	grestore } def\n";
print OUT "/oldshow /showpage load def\n";
print OUT "/oldcopy /copypage load def\n";
print OUT "end\n";
print OUT "    /showpage { DRAFTDICT begin DRAFT oldshow end } def\n";
print OUT "    /copypage { DRAFTDICT begin DRAFT oldcopy end } def\n";
print OUT "% End of draft prelude\n";

while(<IN>){  # Print rest of file to the output file
    print OUT;
}

close (IN) || die "$0: failed to close input file";
close (OUT) || die "$0: failed to close output file";

# Make backup file
rename($filename, "$filename.bak") || die "Unable to rename.";

# Move output file to input file
rename(ps_tmp, $filename) || die "Unable to rename.";