parse-wormedit: guess specific variant of v95 levels

[wormy.git] / parse-wormedit

diff --git a/parse-wormedit b/parse-wormedit
index 26d6cbde3671b3c751a48bd69881f64d6e572d42..bc0d926c27c52cfd5247365e6fcadb1f7a10ecab 100755 (executable)
--- a/parse-wormedit
+++ b/parse-wormedit
@@ -97,39 +97,52 @@ my @FORMAT = (
 
 sub read {
        my ($self, $input) = @_;
-       my ($id, $subid) = (substr($input, 0, 15), ord substr($input, 15, 1));
-       my $version = $opt{version} // $MAGICID{$id}
+       my ($id, $version) = (substr($input, 0, 15), ord substr($input, 15, 1));
+       my $fileversion = $MAGICID{$id}
                or die "File does not match any known WormEdit level header\n";
-       $subid == $version
-               or warn "Unsupported version $subid (expecting $version)\n";
-       given ($version) {
-               when (53) {
-                       # current @FORMAT
+
+       if ($opt{version}) {
+               warn "Override version $version to $opt{version}\n";
+               $version = $opt{version};
+       }
+       elsif ($version != $fileversion) {
+               warn "Unexpected version $version (expecting $fileversion)\n";
+       }
+       elsif ($version == 95) {
+               # auto-detect exact variant
+               if (ord substr($input, 70, 1) ~~ [1 .. 8]) {
+                       # valid sprite length instead of description byte
+                       # (which is usually a letter or nul)
+                       $version = 94;
                }
-               when ($_ <= 95 and $_ > 90) {
-                       ref $_ and pop @$_ for @{ $FORMAT[11] }; # only 8 moderefs
-                       $FORMAT[-1]->[-1]->[0] = '32C'; # less objects
-                       continue;
+               elsif (ord substr($input, 147, 1) == 0) {
+                       # nul of end type is 2 bytes later (unlike first char of endstr)
+                       $version = 96;
                }
-               when (95) {
+               warn "Ambiguous file version 95; guessing subversion $version\n";
+       };
+
+       $fileversion += 100 if $fileversion < 90;  # 93..95 came before 50..53
+       given ($fileversion) {
+               when (153) { } # current @FORMAT
                        $FORMAT[7] = 'Ca64'; # no reserved space after description
-                       #ref $_ and $_->[-1] = 'C' for @{ $FORMAT[11] }; # only 9 moderefs
                        $FORMAT[19] = 'Ca255'; # enddata
-                       splice @FORMAT, 6, 2 if $subid < 95;  # early (sub)version without description
+                       $FORMAT[-1]->[-1]->[0] = '32C'; # less objects
+               when ($version == 96) {
+                       ref $_ and $_->[-1] = 'C' for @{ $FORMAT[11] }; # 9 moderefs
                }
-               when ($_ <= 94 and $_ > 90) {
-                       splice @FORMAT, 6, 2;  # no description
+                       ref $_ and pop @$_ for @{ $FORMAT[11] }; # only 8 moderefs
+                       splice @FORMAT, 6, 2 if $version <= 94;  # earlier version without description
+               when (95) { }
                        splice @{ $FORMAT[7] }, 4, 2;  # no race
                        splice @FORMAT, 16, 2; # no enddata
                        splice @{ $FORMAT[-1] }, 1, 2; # no name
-                       continue if $_ < 94;
-               }
-               when (93) {
+               when (94) { }
                        splice @FORMAT, 16, 2; # no hiname
                        $FORMAT[-1]->[0] = 64; # constant amount of levels
-               }
+               when (93) { }
                default {
-                       die "Cannot parse data for Wormedit $version\n";
+                       die "Cannot parse data for Wormedit $fileversion/$version\n";
                }
        }