#!perl
#Applies wiki formatting to each input file and writes output to <file>.html
open OUT, ">@ARGV[0].html" or die "Could not open @ARGV[0].html";
while (readLine()) {
    escape(); #Apply HTML escaping
    if (pre()) {next} #Print preformatted blocks then continue with next line
    strong(); em(); code(); a(); #Apply in-line formatting
    if (table() or ul() or ol()) {redo} #Print multi-line blocks then continue with current line
    if (h2() or h3() or h4() or hr() or p()) {print OUT "$_\n"; next} #Print single-lines then continue with next line
    print OUT "$_\n" #Print remains
} continue {
    if (eof) {
        close OUT;
        open OUT, ">@ARGV[0].html" or die "Could not open @ARGV[0].html";
    }
}

sub readLine {
    $_ = <>;
    chomp;
    escape();
    return defined $_;
}
sub escape {
    s~&~&amp;~g;
    s~<~&lt;~g;
    s~>~&gt;~g;
}
sub pre {
    if (/^{{{/) {
        s~^{{{~<pre>~;
        print OUT "$_\n";
        while (readLine()) {
            if (/^}}}/) {last}
            print OUT "$_\n";
        }
        s~^}}}~</pre>~;
        print OUT "$_\n";
        return 1;
    }
}
sub strong {s~__(.+?)__~<strong>$1</strong>~g}
sub em {s~''(.+?)''~<em>$1</em>~g}
sub code {s~{{(.+?)}}~<code>$1</code>~g}
sub a {
    if (/\[(.+?)\|(.+?)\]/) {return s~\[(.+?)\|(.+?)\]~<a href='\2.wiki.html'>$1</a>~}
    return s~\[(.+?)\]~<a href='$1.wiki.html'>$1</a>~
}
sub h2 {return s~^!!!+(.*)~<h2>$1</h2>~}
sub h3 {return s~^!!(.*)~<h3>$1</h3>~}
sub h4 {return s~^!(.*)~<h4>$1</h4>~}
sub hr {return s~^---+$~<hr>~}
sub p {return s~^\s*$~<p>~}
sub ul {return list("^\\*", "<ul>\n", "</ul>\n", "\\*")}
sub ol {return list("^#", "<ol>\n", "</ol>\n", "#")}
sub list {
    local ($tag, $start, $end, $continuation) = @_;
    if (/$tag/) {
        print OUT $start;
        li();
        while (readLine()) {
            if (!/$tag/ && !/^ /) {last}
            li();
        }
        print OUT $end;
        return 1;
    }
}
sub li {
    list($tag.$continuation, $start, $end, $continuation);
    s~$tag~<li>~;
    print OUT "$_\n";
}
sub table {
    if (/^\|/) {
        print OUT "<table border='1'>\n";
        row();
        while(readLine()) {
            if (!/^\|/) {last;}
            row();
        }
        print OUT "</table>\n";
        return 1;
    }
}
sub row {
    s~\|\|~<th>~g;
    s~\|~<td>~g;
    print OUT "<tr>$_</tr>\n";
}