wikilink-rewrite.pl

#!/usr/bin/perl

sub rewrite_link {
  my ($orig) = shift;
  if ($orig =~ /(.*)\.chm::(.*)/) {
    my ($chmname, $path) = ($1, $2);
    $chmname = lc $chmname;
    $path =~ s#/#:#g;
    $path =~ s/\.html//;
    return "4c_help:$chmname:$path";
  } else {
    return $orig; # Don't know what it is, don't touch it.
  }
}

while (<>) {
  my $out = "";
  while (1) {
    if (/\G([^[]+)/gc) { # Look for a sequence of text that can't be a link and copy it verbatim
      $out .= $1;
    } elsif (/\G\[\[(.+?)(\||\])/gc) { # Look for the beginning of a link.
      # Take any text starting with "[[" and ending at "|" or "]".
      $out .= "[[" . rewrite_link($1) . $2;
    } elsif (/\G\[/gc) { # Found a "[" that isn't starting a link, copy it to output
      $out .= "[";
    } elsif (/\G\Z/gc) { # Found end of line
      last;
    } else {
      die "Can't happen";
    }
  }
  print $out;
}

# Usage: perl -pi.bak wikilink-rewrite.pl [files...]