#!/usr/bin/perl
use strict;
use warnings;

my $error;
sub parse {
    my $fh = shift;
    my $content = '';

    while( <$fh> ) {
        unless( s[^#include (.+)$][] ) {
            chomp;
            warn "Non-include line '$_' untouched\n";
            $content .= $_ . "\n";
        }
        else{
            local $_ = $1;
            if( m[<math] ) {
                $content .= qq[import java.lang.Math;\n];
            }
            elsif( m["stdafx.h"] ) {
                $content .= qq[#include "stdafx"\n];
            }
            elsif( m["(.+)"] ) {
                open my $inc_handle, '<', $1
                    or warn "$1: $^E\n" and ++$error and next;
                $content .= parse( $inc_handle );
            }
            else {
                warn "Unhandled include $_\n";
                $error++;
            }
        }
    }
    return $content;
}
my $content = parse( \*DATA );

print "\nContent:\n'$content'\n";
die "$error errors encountered\n" if $error;

__DATA__
#include "stdafx.h"
#include <math.h>
#include <stdio.h>
// A comment
#include "AlyLee.h"
#include "Common.h"