#! /usr/bin/perl

# Extract source text files from NASM listing files
#  by E. C. Masloch, 2025
#
# Usage of the works is permitted provided that this
# instrument is retained with the works, so that any entity
# that uses the works is notified of this instrument.
#
# DISCLAIMER: THE WORKS ARE WITHOUT WARRANTY.

use warnings;
use strict;
use Getopt::Long;
Getopt::Long::Configure("no_auto_abbrev");

my $include;

GetOptions(
	'filter-include=s' => \$include,
) or die;

my $includelevel = -1;
my $priorlevel = -1;

while (<<>>) {
  if (/^.{0,39}$/) {
    next;
  }
  if (/^.{0,20}\*{18}\s+/) {
    next;
  }
  my $level = 0;
  if (/^.{30,36}\<([0-9]+)\>\s+/) {
    $level = int($1);
  }
  if (not defined $include and $level != 0) {
    next;
  }
  if (defined $include and /^.{40}\s*\%include\s+['"]*$include['"]*\s*(;.*)?$/i) {
    $priorlevel = $level;
    $includelevel = $level + 1;
  } elsif (defined $include and $level != $includelevel) {
    if ($level <= $priorlevel) {
      last;
    }
    next;
  }
  if (defined $include and $level != $includelevel) {
    next;
  }
  s/^.{40}//;
  print;
}