/+
  extract sdl header return sdl
+/
template SiSUheaderExtractSDLang() {
  private import
    std.regex;
  private import
    ao_rgx;
  struct HeaderExtractSDL {
    mixin RgxInit;
    auto rgx = Rgx();
    final private auto headerMakeSDLang(in string src_header) {
      scope(failure) {
        stderr.writefln(
          "%s\n%s\n%s:%s failed here:\n  src_header: %s",
          __MODULE__, __FUNCTION__,
          __FILE__, __LINE__,
          src_header,
        );
      }
      Tag sdl_root_header;
      try {
        sdl_root_header = parseSource(src_header);
      }
      catch(SDLangParseException e) {
        stderr.writeln("SDLang problem with this document header:");
        stderr.writeln(src_header);
        // Error messages of the form:
        // myFile.sdl(5:28): Error: Invalid integer suffix.
        stderr.writeln(e.msg);
      }
      debug(sdlang) {
        writeln("header SDL:");
        writeln(sdl_root_header.toSDLDocument());
      }
      return sdl_root_header;
    }
    private auto headerSDLangToJSON(in char[] src_header) {
      char[][] source_header_arr =
        split(cast(char[]) src_header, rgx.line_delimiter);
      char[] header_clean;
      // TODO
      foreach(header_line; source_header_arr) {
        if (!match(header_line, rgx.comments)) {
          header_clean ~= header_line ~ "\n";
          // writeln(header_line);
        }
      }
      /+ get sdlang tags +/
      auto header_sdlang=headerMakeSDLang(to!string(header_clean));
      debug(sdlang) {
        writeln("--------------");
        stdout.rawWrite( header_sdlang.toSDLDocument() );
        writeln("--------------");
        Value test = header_sdlang.tags["title"][0].values[0];
        assert(test == typeid(string));
        writeln(header_sdlang.maybe.tags["title"]);
        writeln(header_sdlang.maybe.tags["title"][0].maybe.attributes["subtitle"]);
      }
      /+ TODO separate modules? sdlang then json
      return header_sdlang;
      // then do json module?
      +/
      /+ TODO json next +/
      /+ TODO
        auto dochead_make = parseJSON(header_make_jsonstr).object;
        auto dochead_meta = parseJSON(header_meta_jsonstr).object;
        auto hm = to!string(t.captures[1]);
        auto hs = to!string(s.captures[1]);
        if (dochead_make[hm][hs].type() == JSON_TYPE.STRING) {
          dochead_make[hm][hs].str = to!string(s.captures[2]);
        }
        if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
          dochead_meta[hm][hs].str = to!string(s.captures[2]);
        }
      +/
      /+ dochead +/
      string hm;
      string hs;
      /+ make +/
      auto dochead_make = parseJSON(header_make_jsonstr).object;
      if (!(header_sdlang.maybe.tags["make"].empty)) {
        hm = "make";
        hs = "bold";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "breaks";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "cover_image";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "css";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "emphasis";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "footer";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "headings";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "home_button_image";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "home_button_text";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "italics";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "num_top";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "substitute";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "texpdf_font";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_make[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      /+ meta +/
      auto dochead_meta = parseJSON(header_meta_jsonstr).object;
      hm = "title";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        /+ TODO Title REQUIRED +/
        hs = "main";
        if (!(header_sdlang.tags[hm].empty)
        && (header_sdlang.tags[hm][0].values[0].length > 1)) {
          writeln(header_sdlang.tags[hm][0].values[0]);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].values[0]);
            // to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        } else if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        } else {
          writeln("Required header metadata Title, missing");
        }
        hs = "sub";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        } else if (!(header_sdlang.tags[hm][0].maybe.attributes["subtitle"].empty)
        && (header_sdlang.tags[hm][0].attributes["subtitle"][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes["subtitle"][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes["subtitle"][0].value);
        }
        // full title composite (main + sub)
        // hs = "full";
        // dochead_meta[hm][hs] = dochead_meta[hm]["main"] ~ dochead_meta[hm]["sub"];
        hs = "language";
        if (!(header_sdlang.tags[hm][0].maybe.attributes["lang"].empty)
        && (header_sdlang.tags[hm][0].attributes["lang"][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes["lang"][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes["lang"][0].value);
        } else if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "edition";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "note";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "creator";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        /+ Creator / Author REQUIRED +/
        /+ TODO
        - decide on representation for & deal with multiple authors;
        - author(s) full name;
        - author(s) surname & other parts
        +/
        hs = "author";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "author_email";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "illustrator";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "translator";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "classify";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "dewey";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "keywords";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "loc";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "subject";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "topic_register";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "date";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "added_to_site";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "available";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "created";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "issued";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "modified";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "published";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "valid";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "identifier";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "isbn";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "oclc";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "pg";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "links";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        /+ TODO
          stuff to fix
        +/
        // hs = "link";
        // if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        // && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
        //   writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
        //   dochead_meta[hm][hs].str =
        //     to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        // }
      }
      hm = "notes";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "abstract";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "description";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "original";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "language";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "source";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "title";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "publisher";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "name";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      hm = "rights";
      if (!(header_sdlang.maybe.tags[hm].empty)) {
        hs = "copyright";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "cover";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "illustrations";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
        hs = "license";
        if (!(header_sdlang.tags[hm][0].maybe.attributes[hs].empty)
        && (header_sdlang.tags[hm][0].attributes[hs][0].value.length > 1)) {
          writeln(header_sdlang.tags[hm][0].attributes[hs][0].value);
          dochead_meta[hm][hs].str =
            to!string(header_sdlang.tags[hm][0].attributes[hs][0].value);
        }
      }
      // writeln(dochead_make);
      // writeln(dochead_meta);
      auto t = tuple(dochead_make, dochead_meta);
      static assert(!isTypeTuple!(t));
      return t;
    }
    private auto headerSDLangToHash(in char[] src_header) {
      char[][] source_header_arr =
        split(cast(char[]) src_header, rgx.line_delimiter);
      char[] header_clean;
      string[string] header_make;
      string[string][string] header_metadata;
      foreach(header_line; source_header_arr) {
        if (!match(header_line, rgx.comments)) {
          header_clean ~= header_line ~ "\n";
          // writeln(header_line);
        }
      }
      /+ get sdlang tags +/
      auto header_sdlang=headerMakeSDLang(to!string(header_clean));
      Value test = header_sdlang.tags["title"][0].values[0];
      // assert(test == typeid(string));
      // writeln(header_sdlang.maybe.tags["title"]);
      // writeln(header_sdlang.maybe.tags["title"][0].attributes["subtitle"]);
      if (!(header_sdlang.maybe.tags["make"].empty)) {
        if (!(header_sdlang.tags["make"][0].maybe.attributes["bold"].empty)
        && (header_sdlang.tags["make"][0].attributes["bold"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["bold"][0].value);
          header_make["bold"] =
            to!string(header_sdlang.tags["make"][0].attributes["bold"][0].value);
        } else {
          header_make["bold"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["breaks"].empty)
        && (header_sdlang.tags["make"][0].attributes["breaks"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["breaks"][0].value);
          header_make["breaks"] =
            to!string(header_sdlang.tags["make"][0].attributes["breaks"][0].value);
        } else {
          header_make["breaks"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["cover_image"].empty)
        && (header_sdlang.tags["make"][0].attributes["cover_image"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["cover_image"][0].value);
          header_make["cover_image"] =
            to!string(header_sdlang.tags["make"][0].attributes["cover_image"][0].value);
        } else {
          header_make["cover_image"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["css"].empty)
        && (header_sdlang.tags["make"][0].attributes["css"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["css"][0].value);
          header_make["css"] =
            to!string(header_sdlang.tags["make"][0].attributes["css"][0].value);
        } else {
          header_make["css"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["emphasis"].empty)
        && (header_sdlang.tags["make"][0].attributes["emphasis"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["emphasis"][0].value);
          header_make["emphasis"] =
            to!string(header_sdlang.tags["make"][0].attributes["emphasis"][0].value);
        } else {
          header_make["emphasis"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["footer"].empty)
        && (header_sdlang.tags["make"][0].attributes["footer"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["footer"][0].value);
          header_make["footer"] =
            to!string(header_sdlang.tags["make"][0].attributes["footer"][0].value);
        } else {
          header_make["footer"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["headings"].empty)
        && (header_sdlang.tags["make"][0].attributes["headings"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["headings"][0].value);
          header_make["headings"] =
            to!string(header_sdlang.tags["make"][0].attributes["headings"][0].value);
        } else {
          header_make["headings"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["home_button_image"].empty)
        && (header_sdlang.tags["make"][0].attributes["home_button_image"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["home_button_image"][0].value);
          header_make["home_button_image"] =
            to!string(header_sdlang.tags["make"][0].attributes["home_button_image"][0].value);
        } else {
          header_make["home_button_image"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["home_button_text"].empty)
        && (header_sdlang.tags["make"][0].attributes["home_button_text"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["home_button_text"][0].value);
          header_make["home_button_text"] =
            to!string(header_sdlang.tags["make"][0].attributes["home_button_text"][0].value);
        } else {
          header_make["home_button_text"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["italics"].empty)
        && (header_sdlang.tags["make"][0].attributes["italics"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["italics"][0].value);
          header_make["italics"] =
            to!string(header_sdlang.tags["make"][0].attributes["italics"][0].value);
        } else {
          header_make["italics"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["num_top"].empty)
        && (header_sdlang.tags["make"][0].attributes["num_top"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["num_top"][0].value);
          header_make["num_top"] =
            to!string(header_sdlang.tags["make"][0].attributes["num_top"][0].value);
        } else {
          header_make["num_top"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["substitute"].empty)
        && (header_sdlang.tags["make"][0].attributes["substitute"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["substitute"][0].value);
          header_make["substitute"] =
            to!string(header_sdlang.tags["make"][0].attributes["substitute"][0].value);
        } else {
          header_make["substitute"] = "";
        }
        if (!(header_sdlang.tags["make"][0].maybe.attributes["texpdf_font"].empty)
        && (header_sdlang.tags["make"][0].attributes["texpdf_font"][0].value.length > 1)) {
          writeln(header_sdlang.tags["make"][0].attributes["texpdf_font"][0].value);
          header_make["texpdf_font"] =
            to!string(header_sdlang.tags["make"][0].attributes["texpdf_font"][0].value);
        } else {
          header_make["texpdf_font"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["title"].empty)) {
        /+ Title REQUIRED +/
        if (!(header_sdlang.tags["title"].empty)
        && (header_sdlang.tags["title"][0].values[0].length > 1)) {
          writeln(header_sdlang.tags["title"][0].values[0]);
          header_metadata["title"]["main"] =
            to!string(header_sdlang.tags["title"][0].values[0]);
        } else if (!(header_sdlang.tags["title"][0].maybe.attributes["main"].empty)
        && (header_sdlang.tags["title"][0].attributes["main"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["main"][0].value);
          header_metadata["title"]["main"] =
            to!string(header_sdlang.tags["title"][0].attributes["main"][0].value);
        } else {
          writeln("Required header metadata Title, missing");
          header_metadata["title"]["main"] = "";
        }
        if (!(header_sdlang.tags["title"][0].maybe.attributes["sub"].empty)
        && (header_sdlang.tags["title"][0].attributes["sub"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["sub"][0].value);
          header_metadata["title"]["sub"] =
            to!string(header_sdlang.tags["title"][0].attributes["sub"][0].value);
        } else if (!(header_sdlang.tags["title"][0].maybe.attributes["subtitle"].empty)
        && (header_sdlang.tags["title"][0].attributes["subtitle"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["subtitle"][0].value);
          header_metadata["title"]["sub"] =
            to!string(header_sdlang.tags["title"][0].attributes["subtitle"][0].value);
        } else {
          header_metadata["title"]["sub"] = "";
        }
        // full title composite (main + sub)
        header_metadata["title"]["full"] = header_metadata["title"]["main"] ~ header_metadata["title"]["sub"];
        if (!(header_sdlang.tags["title"][0].maybe.attributes["lang"].empty)
        && (header_sdlang.tags["title"][0].attributes["lang"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["lang"][0].value);
          header_metadata["title"]["language"] =
            to!string(header_sdlang.tags["title"][0].attributes["lang"][0].value);
        } else if (!(header_sdlang.tags["title"][0].maybe.attributes["language"].empty)
        && (header_sdlang.tags["title"][0].attributes["language"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["language"][0].value);
          header_metadata["title"]["language"] =
            to!string(header_sdlang.tags["title"][0].attributes["language"][0].value);
        } else {
          header_metadata["title"]["language"] = "";
        }
        if (!(header_sdlang.tags["title"][0].maybe.attributes["edition"].empty)
        && (header_sdlang.tags["title"][0].attributes["edition"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["edition"][0].value);
          header_metadata["title"]["edition"] =
            to!string(header_sdlang.tags["title"][0].attributes["edition"][0].value);
        } else {
          header_metadata["title"]["edition"] = "";
        }
        if (!(header_sdlang.tags["title"][0].maybe.attributes["note"].empty)
        && (header_sdlang.tags["title"][0].attributes["note"][0].value.length > 1)) {
          writeln(header_sdlang.tags["title"][0].attributes["note"][0].value);
          header_metadata["title"]["note"] =
            to!string(header_sdlang.tags["title"][0].attributes["note"][0].value);
        } else {
          header_metadata["title"]["note"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["creator"].empty)) {
        /+ Creator / Author REQUIRED +/
        /+ TODO
        - decide on representation for & deal with multiple authors;
        - author(s) full name;
        - author(s) surname & other parts
        +/
        if (!(header_sdlang.tags["creator"][0].maybe.attributes["author"].empty)
        && (header_sdlang.tags["creator"][0].attributes["author"][0].value.length > 1)) {
          writeln(header_sdlang.tags["creator"][0].attributes["author"][0].value);
          header_metadata["creator"]["author"] =
            to!string(header_sdlang.tags["creator"][0].attributes["author"][0].value);
        } else {
          header_metadata["creator"]["author"] = "";
        }
        if (!(header_sdlang.tags["creator"][0].maybe.attributes["author_email"].empty)
        && (header_sdlang.tags["creator"][0].attributes["author_email"][0].value.length > 1)) {
          writeln(header_sdlang.tags["creator"][0].attributes["author_email"][0].value);
          header_metadata["creator"]["author_email"] =
            to!string(header_sdlang.tags["creator"][0].attributes["author_email"][0].value);
        } else {
          header_metadata["creator"]["author_email"] = "";
        }
        if (!(header_sdlang.tags["creator"][0].maybe.attributes["illustrator"].empty)
        && (header_sdlang.tags["creator"][0].attributes["illustrator"][0].value.length > 1)) {
          writeln(header_sdlang.tags["creator"][0].attributes["illustrator"][0].value);
          header_metadata["creator"][""] =
            to!string(header_sdlang.tags["creator"][0].attributes["illustrator"][0].value);
        } else {
          header_metadata["creator"]["illustrator"] = "";
        }
        if (!(header_sdlang.tags["creator"][0].maybe.attributes["translator"].empty)
        && (header_sdlang.tags["creator"][0].attributes["translator"][0].value.length > 1)) {
          writeln(header_sdlang.tags["creator"][0].attributes["translator"][0].value);
          header_metadata["creator"]["translator"] =
            to!string(header_sdlang.tags["creator"][0].attributes["translator"][0].value);
        } else {
          header_metadata["creator"][""] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["classify"].empty)) {
        if (!(header_sdlang.tags["classify"][0].maybe.attributes["dewey"].empty)
        && (header_sdlang.tags["classify"][0].attributes["dewey"][0].value.length > 1)) {
          writeln(header_sdlang.tags["classify"][0].attributes["dewey"][0].value);
          header_metadata["classify"]["dewey"] =
            to!string(header_sdlang.tags["classify"][0].attributes["dewey"][0].value);
        } else {
          header_metadata["classify"]["dewey"] = "";
        }
        if (!(header_sdlang.tags["classify"][0].maybe.attributes["keyword"].empty)
        && (header_sdlang.tags["classify"][0].attributes["keyword"][0].value.length > 1)) {
          writeln(header_sdlang.tags["classify"][0].attributes["keyword"][0].value);
          header_metadata["classify"]["keyword"] =
            to!string(header_sdlang.tags["classify"][0].attributes["keyword"][0].value);
        } else {
          header_metadata["classify"]["keyword"] = "";
        }
        if (!(header_sdlang.tags["classify"][0].maybe.attributes["loc"].empty)
        && (header_sdlang.tags["classify"][0].attributes["loc"][0].value.length > 1)) {
          writeln(header_sdlang.tags["classify"][0].attributes["loc"][0].value);
          header_metadata["classify"]["loc"] =
            to!string(header_sdlang.tags["classify"][0].attributes["loc"][0].value);
        } else {
          header_metadata["classify"]["loc"] = "";
        }
        if (!(header_sdlang.tags["classify"][0].maybe.attributes["subject"].empty)
        && (header_sdlang.tags["classify"][0].attributes["subject"][0].value.length > 1)) {
          writeln(header_sdlang.tags["classify"][0].attributes["subject"][0].value);
          header_metadata["classify"]["subject"] =
            to!string(header_sdlang.tags["classify"][0].attributes["subject"][0].value);
        } else {
          header_metadata["classify"]["subject"] = "";
        }
        if (!(header_sdlang.tags["classify"][0].maybe.attributes["topic_register"].empty)
        && (header_sdlang.tags["classify"][0].attributes["topic_register"][0].value.length > 1)) {
          writeln(header_sdlang.tags["classify"][0].attributes["topic_register"][0].value);
          header_metadata["classify"]["topic_register"] =
            to!string(header_sdlang.tags["classify"][0].attributes["topic_register"][0].value);
        } else {
          header_metadata["classify"]["topic_register"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["date"].empty)) {
        if (!(header_sdlang.tags["date"][0].maybe.attributes["added_to_site"].empty)
        && (header_sdlang.tags["date"][0].attributes["added_to_site"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["added_to_site"][0].value);
          header_metadata["date"]["added_to_site"] =
            to!string(header_sdlang.tags["date"][0].attributes["added_to_site"][0].value);
        } else {
          header_metadata["date"]["added_to_site"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["available"].empty)
        && (header_sdlang.tags["date"][0].attributes["available"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["available"][0].value);
          header_metadata["date"]["available"] =
            to!string(header_sdlang.tags["date"][0].attributes["available"][0].value);
        } else {
          header_metadata["date"]["available"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["created"].empty)
        && (header_sdlang.tags["date"][0].attributes["created"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["created"][0].value);
          header_metadata["date"]["created"] =
            to!string(header_sdlang.tags["date"][0].attributes["created"][0].value);
        } else {
          header_metadata["date"]["created"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["issued"].empty)
        && (header_sdlang.tags["date"][0].attributes["issued"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["issued"][0].value);
          header_metadata["date"]["issued"] =
            to!string(header_sdlang.tags["date"][0].attributes["issued"][0].value);
        } else {
          header_metadata["date"]["issued"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["modified"].empty)
        && (header_sdlang.tags["date"][0].attributes["modified"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["modified"][0].value);
          header_metadata["date"]["modified"] =
            to!string(header_sdlang.tags["date"][0].attributes["modified"][0].value);
        } else {
          header_metadata["date"]["modified"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["published"].empty)
        && (header_sdlang.tags["date"][0].attributes["published"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["published"][0].value);
          header_metadata["date"]["published"] =
            to!string(header_sdlang.tags["date"][0].attributes["published"][0].value);
        } else {
          header_metadata["date"]["published"] = "";
        }
        if (!(header_sdlang.tags["date"][0].maybe.attributes["valid"].empty)
        && (header_sdlang.tags["date"][0].attributes["valid"][0].value.length > 1)) {
          writeln(header_sdlang.tags["date"][0].attributes["valid"][0].value);
          header_metadata["date"]["valid"] =
            to!string(header_sdlang.tags["date"][0].attributes["valid"][0].value);
        } else {
          header_metadata["date"]["valid"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["identifier"].empty)) {
        if (!(header_sdlang.tags["identifier"][0].maybe.attributes["isbn"].empty)
        && (header_sdlang.tags["identifier"][0].attributes["isbn"][0].value.length > 1)) {
          writeln(header_sdlang.tags["identifier"][0].attributes["isbn"][0].value);
          header_metadata["identifier"]["isbn"] =
            to!string(header_sdlang.tags["identifier"][0].attributes["isbn"][0].value);
        } else {
          header_metadata["identifier"]["isbn"] = "";
        }
        if (!(header_sdlang.tags["identifier"][0].maybe.attributes["oclc"].empty)
        && (header_sdlang.tags["identifier"][0].attributes["oclc"][0].value.length > 1)) {
          writeln(header_sdlang.tags["identifier"][0].attributes["oclc"][0].value);
          header_metadata["identifier"]["oclc"] =
            to!string(header_sdlang.tags["identifier"][0].attributes["oclc"][0].value);
        } else {
          header_metadata["identifier"]["oclc"] = "";
        }
        if (!(header_sdlang.tags["identifier"][0].maybe.attributes["pg"].empty)
        && (header_sdlang.tags["identifier"][0].attributes["pg"][0].value.length > 1)) {
          writeln(header_sdlang.tags["identifier"][0].attributes["pg"][0].value);
          header_metadata["identifier"]["pg"] =
            to!string(header_sdlang.tags["identifier"][0].attributes["pg"][0].value);
        } else {
          header_metadata["identifier"]["pg"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["links"].empty)) {
        /+ TODO
          stuff to fix
        +/
        if (!(header_sdlang.tags["links"][0].maybe.attributes["link"].empty)
        && (header_sdlang.tags["links"][0].attributes["link"][0].value.length > 1)) {
          writeln(header_sdlang.tags["links"][0].attributes["link"][0].value);
          // header_metadata["links"]["list"] =
          //   to!string(header_sdlang.tags["links"][0].attributes["link"][0].value);
          header_metadata["links"]["list"] = "";
        } else {
          header_metadata["links"]["list"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["notes"].empty)) {
        if (!(header_sdlang.tags["notes"][0].maybe.attributes["abstract"].empty)
        && (header_sdlang.tags["notes"][0].attributes["abstract"][0].value.length > 1)) {
          writeln(header_sdlang.tags["notes"][0].attributes["abstract"][0].value);
          header_metadata["notes"]["abstract"] =
            to!string(header_sdlang.tags["notes"][0].attributes["abstract"][0].value);
        } else {
          header_metadata["notes"]["abstract"] = "";
        }
        if (!(header_sdlang.tags["notes"][0].maybe.attributes["description"].empty)
        && (header_sdlang.tags["notes"][0].attributes["description"][0].value.length > 1)) {
          writeln(header_sdlang.tags["notes"][0].attributes["description"][0].value);
          header_metadata["notes"]["description"] =
            to!string(header_sdlang.tags["notes"][0].attributes["description"][0].value);
        } else {
          header_metadata["notes"]["description"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["original"].empty)) {
        if (!(header_sdlang.tags["original"][0].maybe.attributes["language"].empty)
        && (header_sdlang.tags["original"][0].attributes["language"][0].value.length > 1)) {
          writeln(header_sdlang.tags["original"][0].attributes["language"][0].value);
          header_metadata["original"]["language"] =
            to!string(header_sdlang.tags["original"][0].attributes["language"][0].value);
        } else {
          header_metadata["original"]["language"] = "";
        }
        if (!(header_sdlang.tags["original"][0].maybe.attributes["source"].empty)
        && (header_sdlang.tags["original"][0].attributes["source"][0].value.length > 1)) {
          writeln(header_sdlang.tags["original"][0].attributes["source"][0].value);
          header_metadata["original"]["source"] =
            to!string(header_sdlang.tags["original"][0].attributes["source"][0].value);
        } else {
          header_metadata["original"]["source"] = "";
        }
        if (!(header_sdlang.tags["original"][0].maybe.attributes["title"].empty)
        && (header_sdlang.tags["original"][0].attributes["title"][0].value.length > 1)) {
          writeln(header_sdlang.tags["original"][0].attributes["title"][0].value);
          header_metadata["original"]["title"] =
            to!string(header_sdlang.tags["original"][0].attributes["title"][0].value);
        } else {
          header_metadata["original"]["title"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["publisher"].empty)) {
        if (!(header_sdlang.tags["publisher"][0].maybe.attributes["name"].empty)
        && (header_sdlang.tags["publisher"][0].attributes["name"][0].value.length > 1)) {
          writeln(header_sdlang.tags["publisher"][0].attributes["name"][0].value);
          header_metadata["publisher"]["name"] =
            to!string(header_sdlang.tags["publisher"][0].attributes["name"][0].value);
        } else {
          header_metadata["publisher"]["name"] = "";
        }
      }
      if (!(header_sdlang.maybe.tags["rights"].empty)) {
        if (!(header_sdlang.tags["rights"][0].maybe.attributes["copyright"].empty)
        && (header_sdlang.tags["rights"][0].attributes["copyright"][0].value.length > 1)) {
          writeln(header_sdlang.tags["rights"][0].attributes["copyright"][0].value);
          header_metadata["rights"]["copyright"] =
            to!string(header_sdlang.tags["rights"][0].attributes["copyright"][0].value);
        } else {
          header_metadata["rights"]["copyright"] = "";
        }
        if (!(header_sdlang.tags["rights"][0].maybe.attributes["cover"].empty)
        && (header_sdlang.tags["rights"][0].attributes["cover"][0].value.length > 1)) {
          writeln(header_sdlang.tags["rights"][0].attributes["cover"][0].value);
          header_metadata["rights"]["cover"] =
            to!string(header_sdlang.tags["rights"][0].attributes["cover"][0].value);
        } else {
          header_metadata["rights"]["cover"] = "";
        }
        if (!(header_sdlang.tags["rights"][0].maybe.attributes["illustrations"].empty)
        && (header_sdlang.tags["rights"][0].attributes["illustrations"][0].value.length > 1)) {
          writeln(header_sdlang.tags["rights"][0].attributes["illustrations"][0].value);
          header_metadata["rights"]["illustrations"] =
            to!string(header_sdlang.tags["rights"][0].attributes["illustrations"][0].value);
        } else {
          header_metadata["rights"]["illustrations"] = "";
        }
        if (!(header_sdlang.tags["rights"][0].maybe.attributes["license"].empty)
        && (header_sdlang.tags["rights"][0].attributes["license"][0].value.length > 1)) {
          writeln(header_sdlang.tags["rights"][0].attributes["license"][0].value);
          header_metadata["rights"]["license"] =
            to!string(header_sdlang.tags["rights"][0].attributes["license"][0].value);
        } else {
          header_metadata["rights"]["license"] = "";
        }
      }
      writeln("--------------");
      stdout.rawWrite( header_sdlang.toSDLDocument() );
      writeln("--------------");
      /+
      namespace:name values attributes {
        children
      }
      +/
      return header_sdlang;
    }
    private auto headerSDLang(in char[] src_header) {
      char[][] source_header_arr =
        split(cast(char[]) src_header, rgx.line_delimiter);
      char[] header_clean;
      foreach(header_line; source_header_arr) {
        if (!match(header_line, rgx.comments)) {
          header_clean ~= header_line ~ "\n";
          // writeln(header_line);
        }
      }
      // writeln(header_clean); // consider
      auto header_sdlang=headerMakeSDLang(to!string(header_clean));
      return header_sdlang;
    }
    
  }
  struct HeaderUseSDL {
    mixin RgxInit;
    auto rgx = Rgx();
    // Tag = sdl_header;
    auto headerUseSDLang(T)(auto T sdl_root_header) {
    // T sdl_root_header;
    // auto headerUseSDLang(Tag sdl_root_header) {
    // private auto headerUseSDLang(Tag sdl_root_header) {
    // private auto headerUseSDLang(in Tag sdl_root_header) {
      // auto sdl_root_header = T;

  // Value is a std.variant.Algebraic
  Value test = sdl_root_header.tags["title"][0].values[0];
  // assert(test == typeid(string));
  writeln(test);

      return sdl_root_header;
    }
  }
}
/+
  extract native/orig header return json
+/
template SiSUheaderExtractNative() {
  private import
    std.exception,
    std.regex,
    std.utf,
    std.conv : to;
  private import
    ao_rgx;
  struct HeaderDocMetadataAndMakeNativeToJson {
    mixin SiSUrgxInitFlags;
    mixin RgxInit;
    auto rgx = Rgx();
    enum State { off, on }
    string hm, hs;
    auto header_metadata_and_make_jsonstr(
      string header,
      JSONValue[string] dochead_meta,
      JSONValue[string] dochead_make
    )
    in { }
    body {
      scope(exit) {
        destroy(header);
        destroy(dochead_meta);
        destroy(dochead_make);
      }
      if (auto t = match(header, rgx.native_header_main)) {
        char[][] header_obj_spl = split(
          cast(char[]) header,
          rgx.line_delimiter_ws_strip
        );
        auto hm = to!string(t.captures[1]);
        if (match(hm, rgx.main_headers)) {
          foreach (line; header_obj_spl) {
            if (auto m = match(line, rgx.native_header_main)) {
              if (!empty(m.captures[2])) {
                if (hm == "creator") {
                  dochead_meta[hm]["author"].str =
                    to!string(m.captures[2]);
                } else if (hm == "title") {
                  dochead_meta[hm]["main"].str =
                    to!string(m.captures[2]);
                } else if (hm == "publisher") {
                  dochead_meta[hm]["name"].str =
                    to!string(m.captures[2]);
                }
              }
            } else if (auto s = match(line, rgx.native_header_sub)) {
              if (!empty(s.captures[2])) {
                auto hs = to!string(s.captures[1]);
                if ((hm == "make" )
                && (dochead_make[hm].type() == JSON_TYPE.OBJECT)) {
                  switch (hm) {
                  case "make":
                    if (match(hs, rgx.native_subhead_make)) {
                      if (dochead_make[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_make[hm][hs].str = to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  default:
                    break;
                  }
                } else if (dochead_meta[hm].type() == JSON_TYPE.OBJECT) {
                  switch (hm) {
                  case "creator":
                    if (match(hs, rgx.native_subhead_creator)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "title":
                    if (match(hs, rgx.native_subhead_title)) {
                      if ((hs == "subtitle")
                      && (dochead_meta[hm]["sub"].type() == JSON_TYPE.STRING)) {
                        dochead_meta[hm]["sub"].str =
                          to!string(s.captures[2]);
                      } else if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "rights":
                    if (match(hs, rgx.native_subhead_rights)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "date":
                    if (match(hs, rgx.native_subhead_date)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "original":
                    if (match(hs, rgx.native_subhead_original)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "classify":
                    if (match(hs, rgx.native_subhead_classify)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "identifier":
                    if (match(hs, rgx.native_subhead_identifier)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "notes":
                    if (match(hs, rgx.native_subhead_notes)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "publisher":
                    if (match(hs, rgx.native_subhead_publisher)) {
                      if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                        dochead_meta[hm][hs].str =
                          to!string(s.captures[2]);
                      }
                    } else {
                      writeln("not a valid header type:", hm, ":", hs);
                      destroy(hm);
                      destroy(hs);
                    }
                    break;
                  case "links":
                    destroy(hm);
                    destroy(hs);
                    // if (match(hs, rgx.native_subhead_links)) {
                    //   if (dochead_meta[hm][hs].type() == JSON_TYPE.STRING) {
                    //     dochead_meta[hm][hs].str = to!string(s.captures[2]);
                    //   }
                    // } else {
                    //   writeln("not a valid header type:", hm, ":", hs);
                    //   destroy(hm);
                    //   destroy(hs);
                    // }
                    break;
                  default:
                    break;
                  }
                }
              }
            }
          }
        } else {
          writeln("not a valid header type:", hm);
        }
      }
      auto t = tuple(dochead_meta, dochead_make);
      static assert(!isTypeTuple!(t));
      return t;
    }
    private auto native_header_extract(
      char[] line,
      ref int[string] line_occur,
      ref string[string] an_object,
      ref int[string] type
    ) {
      if (matchFirst(line, rgx.native_header_make)) {   /+ matched header_make +/
        debug(header1) { /+ writeln(line); +/ }
        type["header"]      = State.on;
        type["header_make"] = State.on;
        type["header_meta"] = State.off;
        ++line_occur["header_make"];
        an_object["obj"] ~= line ~= "\n";
      } else if (matchFirst(line, rgx.native_header)) { /+ matched header_metadata +/
        /+ (generic header match and not previously caught by header_make) +/
        debug(header1) { /+ writeln(line); +/ }
        type["header"]      = State.on;
        type["header_make"] = State.off;
        type["header_meta"] = State.on;
        ++line_occur["header_meta"];
        an_object["obj"] ~= line ~= "\n";
      } else if (type["header_make"] == State.on
      && (line_occur["header_make"] > State.off)) {     /+ header_make flag set +/
        if (matchFirst(line, rgx.native_header_sub)) {  /+ sub-header +/
          debug(header1) { /+ writeln(line); +/ }
          ++line_occur["header_make"];
          an_object["obj"] ~= line ~= "\n";
        }
      } else if (type["header_meta"] == State.on
      && (line_occur["header_meta"] > State.off)) {     /+ header_metadata flag set +/
        if (matchFirst(line, rgx.native_header_sub)) {  /+ sub-header +/
          debug(header1) { /+ writeln(line); +/ }
          ++line_occur["header_meta"];
          an_object["obj"] ~= line ~= "\n";
        }
      }
      return an_object;
    }
    auto header_reset_states_common(
      ref int[string] line_occur,
      ref string[string] an_object,
      ref int[string] type
    ) {
      // line_occur["header"] = State.off;
      line_occur["header_make"] = State.off;
      line_occur["header_meta"] = State.off;
      type["header"] = State.off;
      // type["header_make"] = State.off;
      // type["header_meta"] = State.off;
      an_object.remove("obj");
      an_object.remove("is");
      an_object.remove("attrib");
    }
    private auto headerContentJSON(in char[] src_header) {
      auto type = flags_type_init;
      type = [
       "header"          : State.off,
       "header_make"     : State.off,
       "header_meta"     : State.off,
      ];
      string[string] an_object;
      int[string] line_occur;
      auto dochead_make = parseJSON(header_make_jsonstr).object;
      auto dochead_meta = parseJSON(header_meta_jsonstr).object;
      auto set_header = HeaderDocMetadataAndMakeNativeToJson();
      char[][] source_header_arr =
        split(cast(char[]) src_header, rgx.line_delimiter);
      foreach(header_line; source_header_arr) {
        if (auto m = matchFirst(header_line, rgx.comment)) {
          /+ matched comment +/
          debug(comment) {
            // tell_l("blue", header_line);
          }
          header_reset_states_common(line_occur, an_object, type);
          // type["header_make"] = State.off;
          // type["header_meta"] = State.off;
        } else if ((matchFirst(header_line, rgx.native_header))
        || (type["header_make"] == State.on
        && (line_occur["header_make"] > State.off))
        || (type["header_meta"] == State.on
        && (line_occur["header_meta"] > State.off))) {
          if (header_line.length == 0) {
            /+ header_make instructions (current line empty) +/
            auto dochead_metadata_and_make =
              set_header.header_metadata_and_make_jsonstr(strip(an_object["obj"]), dochead_meta, dochead_make);
            static assert(!isTypeTuple!(dochead_metadata_and_make));
            dochead_meta = dochead_metadata_and_make[0];
            dochead_make = dochead_metadata_and_make[1];
            header_reset_states_common(line_occur, an_object, type);
            type["header_make"] = State.off;
            type["header_meta"] = State.off;
            writeln(dochead_metadata_and_make);
          } else {
            an_object = native_header_extract(header_line, line_occur, an_object, type);
          }
        } else {
          // writeln(__LINE__);
        }
      }
      auto t = tuple(
        dochead_make,
        dochead_meta,
      );
      return t;
    }
  }
}