\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{dtk-url}[2011/10/23 v1.0 Urls for DTK (HO)]

\RequirePackage{url}[2006/04/12]

% Konfiguration:
\newcommand*{\DTK@UrlSetup}{\urlstyle{tt}}
\newcommand*{\DTK@UrlCtanSetup}{}
\newcommand*{\DTK@UrlEmailSetup}{}
\newcommand*{\DTK@UrlCtanPrefix}{CTAN:}
\newcommand*{\DTK@UrlCtanServerPrefix}{http://mirror.ctan.org/}
\newcommand*{\DTK@UrlFile}{\jobname.urls}

% Schalter \ifDTK@Url@ legt fest, wann die URLs aktiv sein sollen
\newif\ifDTK@Url@
\ifDTK@Draft@
  \DTK@Url@true
\fi
\ifDTK@lineno@
  \DTK@Url@true
\fi

% Markup-Befehle:
\DeclareRobustCommand*{\url}{\DTK@Url}
\DeclareRobustCommand*{\ctanurl}{\DTK@CtanUrl}
\DeclareRobustCommand*{\Email}{\DTK@Email}
\let\URL\url
\let\CTANurl\ctanurl

\DeclareUrlCommand\DTK@Url{%
  \DTK@UrlSetup
  \def\UrlLeft{}%
  \def\UrlRight{}%
  \def\DTK@UrlType{url}%
}
\DeclareUrlCommand\DTK@CtanUrl{%
  \DTK@UrlSetup
  \DTK@UrlCtanSetup
  \let\UrlLeft\DTK@UrlCtanPrefix
  \def\UrlRight{}%
  \let\DTK@UrlLinkPrefix\DTK@UrlCtanServerPrefix
  \def\DTK@UrlType{ctanurl}%
}
\DeclareUrlCommand\DTK@Email{%
  \DTK@UrlSetup
  \DTK@UrlEmailSetup
  \def\UrlLeft{}%
  \def\UrlRight{}%
  \def\DTK@UrlLinkPrefix{mailto:}%
  \def\DTK@UrlType{email}%
}
\def\DTK@UrlType{unknown}

% Implementierung

\RequirePackage{pdfescape}

% Currently only pdfTeX/LuaTeX in PDF mode are supported
\RequirePackage{ifpdf}
\ifpdf
\else
  % Other engines then pdfTeX and LuaTeX in PDF mode
  % are not supported
  \DTK@Url@false
\fi

% Ensure that the needed primitives are enabled in LuaTeX
\RequirePackage{ifluatex}
\ifluatex
  \directlua{tex.enableprimitives('',{'pdfstartlink','pdfendlink'})}%
\fi

\let\DTK@UrlLinkPrefix\@empty
\ifDTK@Url@
  \def\Url@HyperHook#1{%
    \begingroup
      \DTK@UrlPercent
      \edef\#{\string##}%
      \edef\DTK@Temp{\DTK@UrlLinkPrefix\Url@String\@empty}%
      \@onelevel@sanitize\DTK@Temp
      \edef\DTK@UrlRaw{\Url@String\@empty}%
      \@onelevel@sanitize\DTK@UrlRaw
      \edef\x{\endgroup
        \noexpand\EdefEscapeString\noexpand\DTK@Temp{\DTK@Temp}%
        \def\noexpand\DTK@Raw{\DTK@UrlRaw}%
      }%
    \x
    \DTK@UrlWrite{\DTK@UrlType}{\DTK@Raw}%
    \pdfstartlink attr{%
      /H/I%
      /C[1 0 0]% red
      /Border[1 0 0]%
      /BS<</S/U/W 1>>%
    }%
    user{%
      /Subtype/Link
      /A<<%
        /Type/Action%
        /S/URI%
        /URI(\DTK@Temp)%
      >>%
    }%
    #1%
    \pdfendlink
  }%

  % Implement writing of file \DTK@UrlFile
  \if@filesw
    \RequirePackage{atveryend}%
    \RequirePackage{embedfile}%
    \newwrite\DTK@UrlHandle
    \openout\DTK@UrlHandle=\DTK@UrlFile\relax
    \begingroup
      \count@\time
      \divide\count@ by 60 %
      \count2=-\count@
      \multiply\count2 by 60 %
      \advance\count2 \time
      \edef\x{\endgroup
        \write\DTK@UrlHandle{%
          \@percentchar\space
          \the\year-\two@digits\month-\two@digits\day
          \space\two@digits\count@:\two@digits{\count2 }, %
          format: <page> <type> <data>%
        }%
      }%
    \x
    \def\DTK@UrlWrite#1#2{%
      \protected@write\DTK@UrlHandle{}{%
        \thepage\space#1 #2%
      }%
    }%
    \let\DTK@embedfilefinish\embedfilefinish
    \let\embedfilefinish\relax
    \AfterLastShipout{%
      \immediate\closeout\DTK@UrlHandle
      \embedfile[%
        mimetype=text/plain,%
        stringmethod=escape,%
        desc={%
          List of URLs found in %
          \@backslashchar url and \@backslashchar ctanurl%
        },%
      ]{\DTK@UrlFile}%
      \DTK@embedfilefinish
    }%
  \else
    \let\DTK@UrlWrite\@gobbletwo
  \fi
\fi

\begingroup
  \lccode`\~=`\%
\lowercase{\endgroup
  \def\DTK@UrlPercent{\let~\DTK@UrlPercentCR}%
}
\begingroup
  \lccode`\0=`\^^M
\lowercase{\endgroup
  \def\DTK@UrlPercentCR#1{%
    \ifx0#1\@empty
      \expandafter\@gobble
    \else
      \expandafter\@firstofone
    \fi
    {\@percentchar#1}%
  }%
}
\endinput