::    ++down rendering arms
::
::::  /hoon/rend/down-jet/lib
  ::
/?    310
/-  *markdown
::
=,  format
=,  html
::
|%
++  into-inner
  |=  {a/marl b/manx}
  ?~  c.b  b(c a)
  $(b i.c.b)
::
++  flat
  |=  a/marl
  ^-  tape
  ?~  a  ~
  %+  weld
    ^-  tape
    ?~  n.g.i.a
      ?>(?=(_;/(**) i.a) v.i.a.g.i.a)
    ?+    n.g.i.a  $(a c.i.a)
        $img
      %-  zing  ^-  wall
      %+  murn  a.g.i.a   |=  {a/mane b/tape}  
      ^-  (unit tape)
      ?+  a  ~
        $alt  [~ b]
      ==
    ==
  $(a t.a)
::  
++  sanitize
 |=  a/marl  ^-  tape
 =-  (zing `wall`(scan (flat a) fel))
 =<  fel=;~(sfix (star ;~(plug (cold '-' -) (plus +))) (star next)) 
 [(star ;~(less aln prn)) ;~(pose nud low (cook |=(a/@ (add a ' ')) hig))]
::
++  sang                                                ::  tight item children
  |=  a/(list elem)
  ^-  marl
  ?~  a  ~
  %+  weld  
    ?.  ?=($para -.i.a)
      (sing i.a ~)
    (sung p.i.a)
  $(a t.a)
::
++  sing                                                ::  elem to manx
  =,  html
  =>  |%
      ++  first-word
        |=  a/tape
        =.  a  (trip (crip a))                          ::  XX valid tapes
        ^-  (unit tape)
        =.  a  q.q:(need q:((star ace) [1 1] a))
        =+  vex=((plus ;~(less ace prn)) [1 1] a)
        ?~  q.vex  ~
        (some (wonk vex))
      --
  =+  [tig=| had=*(unit mane)]
  |=  lum/(list elem)
  |^  ^-  marl
      =+  a=apex
      ?~  q.a
        p.a
      (weld p.a $(lum q.a))
  ::
  ++  apex
    ^-  {p/marl q/_lum}  
    ?~  lum  
      ?~  had  [~ ~]
      (lose "unclosed {<u.had>}")
    =>  [ele=i.lum .(lum t.lum)]
    ?.  ?=($html -.ele)
      (push (reso ele) ~)
    ::  begin reparsing of html that the spec jankily lets through  ::
    =+  tex=(trip (of-wain p.ele))
    =^  mar  lum  (chomp tex (sear |=(a/marl ?~(a ~ (some a))) many:de-xml))
    ?^  mar
      (push u.mar)
    =^  hed  lum  (chomp tex head:de-xml)
    ?^  hed
      =+  max=`marx`u.hed
      (push(lum q) [max p] ~):[apex(had `n.max) .]
    =^  tal  lum  (chomp tex tail:de-xml)
    ?~  tal
      =^  cha  lum  (chomp tex prn)
      ?^  cha
        (push ;/([u.cha]~) ~)
      (push ;lost:"{tex}" ~)
    ?:  =(had tal)
      [~ lum]
    ?^  had
      =.  lum  [ele lum]
      (lose "unclosed {<u.had>}")
    (lose "close {<u.tal>}")
    ::  end reparsing of html that the spec jankily lets through  ::
  ::
  ++  lose  |=(a/tape [[;lost:"{a}"]~ lum])
  ++  chomp
    |*  {tap/tape fel/rule}
    ^-  {(unit _(wonk *fel)) _lum}  
    =+  vex=(fel 1^1 tap)
    ?~  q.vex  [~ lum]
    :-  [~ (wonk vex)]
    ?~(q.q.u.q.vex lum [[%html (to-wain (crip q.q.u.q.vex))] lum])
  ::
  ++  push
    |=  a/marl
    ^+  apex
    ?~  a  apex
    [[b p] q]:[b=i.a (push t.a)]
  ::
  ++  reso
    |=  a/elem
    ?^  -.a
      =.  tig  ?.(?=($list -.p.a) tig p.p.a)
      ?:  &(tig ?=($item -.p.a))
        [/li (sang q.a)]
      %+  into-inner  ^$(lum q.a)
      ?-  -.p.a
        $bloq  ;blockquote;
        $item  ;li;
        $list  ?@  q.p.a  ;ul;
               ?:  =(1 p.q.p.a)  ;ol;
               =+  num=(en-json (numb:enjs p.q.p.a))
               ;ol(start num);
      ==
    ?-  -.a  ::  ;/("unimplemented {<p.a>}")
      $html  !!                       ::  handled earlier   XX do type stuff
      $para  [/p (sung p.a)]
      $head  
        =+  [hed=(add %h0 (lsh 3 1 p.a)) kid=(sung q.a)]
        [[hed id+(sanitize kid) ~] kid]
    ::
      $hrul  ;hr;
      $meta  ?:  =(~ p.a)  ;/(~)
             =+  jon=`json`o+(~(run by p.a) |=(cord s++<))
             ;meta(value "{(en-json jon)}", name "frontmatter", urb_front "");
  ::     %html  
             ::=+  tex=(of-wain (turn p.a crip))
             ::=+  (de-xml tex)
             ::?^  -  u.-
             ::=+  (rush tex (star ;~(pose gah comt:de-xml)))
             ::?^  -  ;/(~)
             ::;lost: {<p.a>}
        :: ;/([(of-wain (turn p.a crip))]~)                ::  XX  haaaaaaack
      $defn  ;/(~)
      $code  =+  lan=?~(p.a ~ (first-word r.u.p.a))
             =+  tex=(trip (of-wain q.a))
             ?~  lan  ;pre:code:"{tex}"
             ;pre:code(class "language-{u.lan}"):"{tex}"

    ==
  --
::  
++  sung
  |=  lim/kids
  =+  had=*(unit mane)
  |^  ^-  marl
      =+  a=apex
      ?~  q.a
        p.a
      (weld p.a $(lim q.a))
  ::
  ++  apex
    ^-  {p/marl q/_lim}
    ?~  lim  
      ?~  had  [~ ~]
      (lose "unclosed {<u.had>}")
    =>  [ele=i.lim .(lim t.lim)]
    ?.  ?=($htmt -.ele)
      ?:  &(?=($$ -.ele) ?=({{$$ *} *} lim))
        apex(p.i.lim (weld p.ele p.i.lim))  
      (push (reso ele) ~)
    =+  tex=(trip p.ele)
    =^  emo  lim  (chomp tex empt:de-xml)
    ?^  emo
      =+  man=`manx`u.emo
      (push man ~)
    =^  hed  lim  (chomp tex head:de-xml)
    ?^  hed
      =+  max=`marx`u.hed
      (push(lim q) [max p] ~):[apex(had `n.max) .]
    =^  tal  lim  (chomp tex tail:de-xml)
    ?~  tal
      (push ;lost:"{tex}" ~)
    ?:  =(had tal)
      [~ lim]
    ?^  had
      =.  lim  [ele lim]
      (lose "unclosed {<u.had>}")
    (lose "unopened {<u.tal>}")
  ::
  ++  lose  |=(a/tape [[;lost:"{a}"]~ lim])
  ++  chomp
    |*  {tap/tape fel/rule}
    ^-  {(unit _(wonk *fel)) _lim}
    =+  vex=(fel 1^1 tap)
    ?~  q.vex  [~ lim]
    :-  [~ (wonk vex)]
    ?~(q.q.u.q.vex lim [[%htmt (crip q.q.u.q.vex)] lim])
  ::
  ++  push
    |=  a/marl
    ^+  apex
    ?~  a  apex
    [[b p] q]:[b=i.a (push t.a)]
  ::
  ++  urly
    |=  a/tape  ^-  tape
    ?~  a  ~
    ?:  ?|  [?=(^ q)]:(alp 1^1 a)
            (~(has in (silt "#!*'();:@&=+$,/?/%.~_")) i.a) ::  XX  reparse
        ==
      [i.a $(a t.a)]
    (weld (en-urlt:html (trip i.a)) $(a t.a))
  ::
  ++  reso
    |=  b/inline
    ^-  manx
    ?@  -.b
      ?-  -.b
        $$     ;/(p.b)  
        $line  ;br;
        $code  ;code:"{p.b}"
        $htmt  !!  ::p.b              ::  handled earlier ::  XX  do type stuff
      ==
    ?:  ?=($blot -.p.b)
      =+  res=`manx`;img(src (urly p.p.b), alt (flat (turn q.b ..$)));
        :: ;img@"{p.p.b}";
      ?~  q.p.b  res
      res(a.g (welp a.g.res title+u.q.p.b ~))
    =+  kid=(sung q.b)
    %+  into-inner  kid
    ?-  p.b
      {$emph ?}   ?.(p.p.b ;em; ;strong;)
      {$delt ~}  ;del;
      {$link ^}   =+  url=(urly p.p.b)
                  =.  url  ?^(url url "#{(sanitize kid)}")
                  ?~  q.p.b  ;a/"{url}";
                  ;a/"{url}"(title u.q.p.b);
    ==
  --
--