#!/usr/bin/perl

# Reads in a C64 binary PRG containing sprites and outputs P65 assembly for them.

# SPDX-FileCopyrightText: Chris Pressey, the original author of this work, has dedicated it to the public domain.
# For more information, please refer to <https://unlicense.org/>
# SPDX-License-Identifier: Unlicense

open FILE, "<$ARGV[0]";
binmode FILE;

my $len, $buffer;

read FILE, $len, 2;

printf ".org \$%02x%02x\n\n", ord(substr($len, 1, 1)), ord(substr($len, 0, 1));

read FILE, $buffer, 64;
while (not eof(FILE))
{
    my $offset = 0;
    for ($i = 0; $i < 21; $i++)
    {
        printf ".byte \$%02x,\$%02x,\$%02x\n",
          ord(substr($buffer, $offset, 1)),
          ord(substr($buffer, $offset+1, 1)),
          ord(substr($buffer, $offset+2, 1));
        $offset += 3;
    }
    print "\n.byte 0\n\n";   # padding
    read FILE, $buffer, 64;
}

close FILE;