\fontfam[lm]
\hyperlinks\Blue\Blue

% Set options of the Markdown module
\_def \markdownOptions {
  cacheDir="_markdown_example",
  definitionLists=true,
  fencedCode=true,
  hashEnumerators=true,
  smartEllipses=true,
  strikeThrough=true,
}

% Set renderers of the Markdown module
%% Attribute Renderers
%%% TODO

%% Block Quote Renderers
\_def  \markdownRendererBlockQuoteBegin {\_begblock}
\_def  \markdownRendererBlockQuoteEnd {\_endblock}

%% Bracketed Spans Attribute Context Renderers
%%% TODO

%% Bullet List Renderers
\_def  \markdownRendererUlBegin       {\_begitems \_itemskipamount=\_olistskipamount}
\_def  \markdownRendererUlBeginTight  {\_begitems}
\_def  \markdownRendererUlItem        {\_startitem}
\_def  \markdownRendererUlItemEnd     {\_par}
\_def  \markdownRendererUlEnd         {\_enditems}
\_def  \markdownRendererUlEndTight    {\_enditems}

%% Citations Renderers
%%% TODO

%% Code Block Renderers
\_def  \markdownRendererInputVerbatim #1{\_verbinput (-) {#1} }
\_def  \markdownRendererInputFencedCode #1#2{\_verbinput \_hisyntax{#2} (-) {#1} }

%% Code Span Renderer
\_def  \markdownRendererCodeSpan    #1{{\_ttfont #1}}

%% Code Span Attribute Context Renderers
%%% TODO

%% Content Block Renderers
%%% TODO

%% Definition List Renderers
\_sdef{_item:d}{\_aftergroup\dword}
\_def  \dword                     #1#2{{\bf#2 }\ignorespaces}
\_def  \markdownRendererDlBegin       {\_begitems \_style d \_itemskipamount=\_olistskipamount}
\_def  \markdownRendererDlBeginTight  {\_begitems \_style d}
\_def  \markdownRendererDlItem        {%
  \_begingroup
  \_def \markdownRendererInterblockSeparator {%
    \_par
    \_advance\_leftskip by\_iindent
    \_def \markdownRendererInterblockSeparator {\_par}%
  }%
  \_startitem
}
\_def  \markdownRendererDlItemEnd     {%
  \_par
  \_endgroup
}
\_def  \markdownRendererDlDefinitionBegin {}
\_def  \markdownRendererDlDefinitionEnd #1{%
  \_ifx #1\markdownRendererDlDefinitionBegin
    \_firstnoindent
    \markdownRendererInterblockSeparator
    \_vskip\_itemskipamount
  \_fi
  #1%
}
\_def  \markdownRendererDlEnd         {\_enditems}
\_def  \markdownRendererDlEndTight    {\_enditems}

%% Ellipsis Renderer
\_def  \markdownRendererEllipsis      {$\_ldots$}

%% Emphasis Renderers
\_def  \markdownRendererEmphasis    #1{{\_em #1}}
\_def  \markdownRendererStrongEmphasis #1{{\_bf #1}}

%% Fenced Code Attribute Context Renderers
%%% TODO

%% Fenced Div Attribute Context Renderers
%%% TODO

%% Header Attribute Context Renderers
%%% TODO

%% Heading Renderers
\_def  \markdownRendererHeadingOne  #1{\_printtit{#1}}
\_def  \markdownRendererHeadingTwo  #1{\_inchap{#1}}
\_def  \markdownRendererHeadingThree #1{\_insec{#1}}
\_def  \markdownRendererHeadingFour #1{\_insecc{#1}}
\_def  \markdownRendererHeadingFive #1{{\_bf #1}\_firstnoindent}
\_def  \markdownRendererHeadingSix  #1{#1\_firstnoindent}

%% HTML Comment Renderers
%%% TODO

%% HTML Tag and Element Renderers
%%% TODO

%% Image Renderer
\_def  \markdownRendererImage #1#2#3#4{%
  \_topinsert
  \_centerline{\_inspic{#3}}%
  \_cskip
  \_caption/f #4%
  \_par
  \_endinsert
}

%% Image Attribute Context Renderers
%%% TODO

%% Interblock Separator Renderer
\_def  \markdownRendererInterblockSeparator {\_par}
\_def  \markdownRendererParagraphSeparator  {\markdownRendererInterblockSeparator}

%% Line Block Renderers
%%% TODO

%% Line Break Renderers
\_def  \markdownRendererSoftLineBreak { }
\_def  \markdownRendererHardLineBreak {\_nl}

%% Link Renderer
\_def  \markdownRendererLink  #1#2#3#4{\_ea\_ulink\_ea[\_expanded{#3}]{#1}}

%% Link Attribute Context Renderers
%%% TODO

%% Markdown Document Renderers
\_let  \markdownRendererDocumentBegin \_relax
\_let  \markdownRendererDocumentEnd   \_relax

%% Non-Breaking Space Renderer
\_def  \markdownRendererNbsp          {~}

%% Note Renderer
%%% TODO

%% Ordered List Renderers
\_def  \markdownRendererOlBegin       {\_begitems \_style n \_itemskipamount=\_olistskipamount}
\_def  \markdownRendererOlBeginTight  {\_begitems \_style n}
\_def  \markdownRendererFancyOlBegin #1#2{\markdownRendererOlBegin}
\_def  \markdownRendererFancyOlBeginTight #1#2{\markdownRendererOlBeginTight}
\_def  \markdownRendererOlItem        {\_startitem}
\_def  \markdownRendererOlItemEnd     {\_par}
\_def  \markdownRendererOlItemWithNumber #1{\_itemnum=#1 \_advance\_itemnum by -1 \_startitem}
\_let  \markdownRendererFancyOlItem   \markdownRendererOlItem
\_let  \markdownRendererFancyOlItemEnd \markdownRendererOlItemEnd
\_let  \markdownRendererFancyOlItemWithNumber \markdownRendererOlItemWithNumber
\_def  \markdownRendererOlEnd         {\_enditems}
\_def  \markdownRendererOlEndTight    {\_enditems}
\_let  \markdownRendererFancyOlEndTight \markdownRendererOlEndTight
\_let  \markdownRendererFancyOlEnd   \markdownRendererOlEnd

%% Raw Content Renderers
%%% TODO

%% Section Renderers
\_let  \markdownRendererSectionBegin  \_relax
\_let  \markdownRendererSectionEnd    \_relax

%% Replacement Character Renderers
\_def  \markdownRendererReplacementCharacter {^^^^fffd}

%% Special Character Renderers
\_edef \markdownRendererAmpersand   #1{\_csstring\&}
\_edef \markdownRendererBackslash   #1{\_csstring\\}
\_edef \markdownRendererCircumflex  #1{\_csstring\^}
\_edef \markdownRendererDollarSign  #1{\_csstring\$}
\_edef \markdownRendererHash        #1{\_csstring\#}
\_edef \markdownRendererLeftBrace   #1{\_csstring\{}
\_edef \markdownRendererPercentSign #1{\_csstring\%}
\_def  \markdownRendererPipe        #1{|}
\_edef \markdownRendererRightBrace  #1{\_csstring\}}
\_edef \markdownRendererTilde       #1{\_csstring\~}
\_def  \markdownRendererUnderscore  #1{_}

%% Strike-Through Renderer
\_def  \markdownRendererStrikeThrough #1{%
  \_setbox0=\_hbox {#1}%
  \_leavevmode
  \_rlap {\raise.5ex \_hbox to \_wd0 {\_hfil \_hrulefill \_hfil}}%
  \_box0
}

%% Subscript Renderer
%%% TODO

%% Superscript Renderer
%%% TODO

%% Table Renderer
%%% TODO

%% TeX Math Renderers
%%% TODO

%% Thematic Break Renderer
\_def  \markdownRendererThematicBreak {%
  \_vskip 0.5\_baselineskip
  \_hrule
  \_par
  \_vskip 0.5\_baselineskip
  \_firstnoindent
}

%% Tickbox Renderers
%%% TODO

%% YAML Metadata Renderers
\_let  \markdownRendererJekyllDataBegin \_relax
\_let  \markdownRendererJekyllDataEnd \_relax
\_def  \markdownRendererJekyllDataMappingBegin #1#2{}
\_let  \markdownRendererJekyllDataMappingEnd \_relax
\_def  \markdownRendererJekyllDataSequenceBegin #1#2{}
\_let  \markdownRendererJekyllDataSequenceEnd \_relax
\_def  \markdownRendererJekyllDataBoolean #1#2{}
\_def  \markdownRendererJekyllDataNumber #1#2{}
\_def  \markdownRendererJekyllDataString #1#2{}
\_def  \markdownRendererJekyllDataEmpty #1{}

% Load the Markdown module and set TeX macros for the Markdown module
\_directlua{
  kpse = require("kpse")
  kpse.set_program_name("luatex")
  markdown = require("markdown")
}

\_eoldef \markdownBegin #1{% #1 includes the end of the current line, parameters can be here
   \_def\_markdownParams{#1}%
   \_bgroup \_setverb \_savemathsb \_endlinechar=`\^^J
   \_markdownBeginA
}

\_ea\_def \_ea\_markdownBeginA \_ea#\_ea1\_csstring\\markdownEnd#2^^J{%
  \_restoremathsb \_egroup
  \_bgroup
  \_catcode`\%=12\_relax
  \_catcode`\#=12\_relax
  \_directlua {
    % Prepare a table of options.
    local defaultOptions = {\markdownOptions}
    local currentOptions = {\_markdownParams}
    local options = {}
    for k,v in pairs(defaultOptions) do options[k] = v end
    for k,v in pairs(currentOptions) do options[k] = v end
    % Ensure that the cache directory exists.
    if options.cacheDir then
      local lfs = require("lfs")
      if not lfs.isdir(options.cacheDir) then
        assert(lfs.mkdir(options.cacheDir))
      end
    end
    % Convert Markdown to TeX and print it.
    local convert = markdown.new(options)
    local input = "\_luaescapestring{#1}"
    local output = convert(input)
    tex.print(output)
  }%
  \_egroup
}

% Set the document metadata using a YAML metadata block
\markdownBegin hybrid=true,jekyllData=true
---
title:  An Example *Markdown* Document
author: Vít Starý Novotný
date:   \today
---

# This is an H1

## This is an H2

### This is an H3

#### This is an H4

##### This is an H5

###### This is an H6

This is a text paragraph containing an ellipsis ... and followed by a
thematic break.

***

This is inline `code`. This is a [link](http://google.cz "Google").
This is an *emphasized* span of text.
This is a __strongly emphasized__ span of text.

  ![example image](example-image.png "An example image from Martin Scharrer's mwe package")

This is a fenced code block:

``` tex
\fontfam[LMfonts]
Hello World! \bye
```

This is a bullet list:

* The first item of a bullet list,

* the second item of a bullet list,

* the third item of a bullet list.

This is a compact bullet list:

* The first item of a bullet list,
* the second item of a bullet list,
* the third item of a bullet list.

This is an ordered list:

5. The first item of an ordered list,

6. the second item of an ordered list,

7. the third item of an ordered list.

This is an ordered list using hash enumerators:

#. The first item of an ordered list,

#. the second item of an ordered list,

#. the third item of an ordered list.

This is a compact ordered list:

5. The first item of an ordered list,
6. the second item of an ordered list,
7. the third item of an ordered list.

This is a compact ordered list using hash enumerators:

#. The first item of an ordered list,
#. the second item of an ordered list,
#. the third item of an ordered list.

This is a definition list:

Term 1

:   Definition 1 with some ~~removed text~~

Term 2

:   Definition 2

        Some code, part of Definition 2

    Third paragraph of Definition 2.

:   Definition 3

This is a compact definition list:

Term 1
:   Definition 1
Term 2
:   Definition 2
:   Definition 3

\markdownEnd

\bye