
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; MODULE      : tmhtml.scm
;; DESCRIPTION : conversion of TeXmacs trees into Html trees
;; COPYRIGHT   : (C) 2002  Joris van der Hoeven, David Allouche
;;
;; This software falls under the GNU general public license version 3 or later.
;; It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
;; in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(texmacs-module (convert html tmhtml)
  (:use (convert tools tmconcat)
	(convert mathml tmmath)
	(convert tools stm)
	(convert tools tmlength)
	(convert tools tmtable)
	(convert tools old-tmtable)
	(convert tools sxml)
	(convert tools sxhtml)
	(convert html htmlout)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Initialization
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define tmhtml-env (make-ahash-table))
(define tmhtml-css? #t)
(define tmhtml-mathml? #f)
(define tmhtml-images? #f)
(define tmhtml-image-serial 0)
(define tmhtml-image-cache (make-ahash-table))
(define tmhtml-image-root-url (string->url "image"))
(define tmhtml-image-root-string "image")

(tm-define (tmhtml-initialize opts)
  (set! tmhtml-env (make-ahash-table))
  (set! tmhtml-css?
	(== (assoc-ref opts "texmacs->html:css") "on"))
  (set! tmhtml-mathml?
	(== (assoc-ref opts "texmacs->html:mathml") "on"))
  (set! tmhtml-images?
	(== (assoc-ref opts "texmacs->html:images") "on"))
  (set! tmhtml-image-cache (make-ahash-table))
  (let* ((suffix (url-suffix current-save-target))
	 (n (+ (string-length suffix) 1)))
    (if (in? suffix '("html" "xhtml"))
	(begin
	  (set! tmhtml-image-serial 0)
	  (set! tmhtml-image-root-url (url-unglue current-save-target n))
	  (set! tmhtml-image-root-string
		(url->string (url-tail tmhtml-image-root-url))))
	(begin
	  (set! tmhtml-image-serial 0)
	  (set! tmhtml-image-root-url (string->url "image"))
	  (set! tmhtml-image-root-string "image")))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Empty handler and strings
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-noop l) '())

(define (cork->html s)
  (utf8->html (cork->utf8 s)))

(define (tmhtml-sub-token s pos)
  (with ss (substring s pos (- (string-length s) 1))
    (if (= (string-length ss) 1) ss
	(tmhtml-math-token (string-append "<" ss ">")))))

(define (tmhtml-math-token s)
  (cond ((= (string-length s) 1)
	 (cond ((== s "*") " ")
	       ((in? s '("+" "-" "=")) (string-append " " s " "))
	       ((char-alphabetic? (string-ref s 0)) `(h:var ,s))
	       (else s)))
	((string-starts? s "<cal-")
	 `(h:font (@ (face "Zapf Chancery")) ,(tmhtml-sub-token s 5)))
	((string-starts? s "<b-cal-")
	 `(h:u (h:font (@ (face "Zapf Chancery")) ,(tmhtml-sub-token s 7))))
	((string-starts? s "<frak-")
	 `(h:u ,(tmhtml-sub-token s 6)))
	((string-starts? s "<bbb-") `(h:u (h:b ,(tmhtml-sub-token s 5))))
	((string-starts? s "<b-") `(h:b (h:var ,(tmhtml-sub-token s 3))))
	((string-starts? s "<")
	 (with encoded (cork->utf8 s)
	   (utf8->html (if (== s encoded)
			   (old-tm->xml-cdata s)
			   encoded))))
	(else s)))

(define (tmhtml-string s)
  (if (ahash-ref tmhtml-env :math)
      (tmhtml-post-simplify-nodes
       (map tmhtml-math-token (tmconcat-tokenize-math s)))
      (list (cork->html s))))

(define (tmhtml-text s)
  (if (or (ahash-ref tmhtml-env :math) (ahash-ref tmhtml-env :preformatted))
      (tmhtml-string s)
      (tmhtml-string (make-ligatures s))))

(define cork-endash (char->string (integer->char 21)))
(define cork-ldquo (char->string (integer->char 16)))
(define cork-rdquo (char->string (integer->char 17)))

(define (make-ligatures s)
  ;; Make texmacs ligatures in Cork encoding  
  (string-replace
   (string-replace
    (string-replace s "--" cork-endash) "``" cork-ldquo) "''" cork-rdquo))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Entire documents
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-find-title doc)
  (cond ((npair? doc) #f)
	((func? doc 'doc-title 1) (cadr doc))
	((func? doc 'tmdoc-title 1) (cadr doc))
	((func? doc 'tmdoc-title* 2) (cadr doc))
	((func? doc 'tmdoc-title** 3) (caddr doc))
	((func? doc 'hidden-title 1) (cadr doc))
	(else (with title (tmhtml-find-title (car doc))
		(if title title
		    (tmhtml-find-title (cdr doc)))))))

(define (tmhtml-css-header)
  (let ((html
	 (string-append
	  "body { text-align: justify } "
	  "h5 { display: inline; padding-right: 1em } "
	  "h6 { display: inline; padding-right: 1em } "
	  "table { border-collapse: collapse } "
	  "td { padding: 0.2em; vertical-align: baseline } "
	  ".subsup { display: inline; vertical-align: -0.2em } "
	  ".subsup td { padding: 0px; text-align: left} "
	  ".fraction { display: inline; vertical-align: -0.8em } "
	  ".fraction td { padding: 0px; text-align: center } "
	  ".wide { position: relative; margin-left: -0.4em } "
	  ".accent { position: relative; margin-left: -0.4em; top: -0.1em } "
	  ".title-block { width: 100%; text-align: center } "
	  ".title-block p { margin: 0px } "
	  ".compact-block p { margin-top: 0px; margin-bottom: 0px } "
	  ".left-tab { text-align: left } "
	  ".center-tab { text-align: center } "
	  ".right-tab { float: right; position: relative; top: -1em } "))
	(mathml "math { font-family: cmr, times, verdana } "))
    (if tmhtml-mathml? (string-append html mathml) html)))

(define (tmhtml-file l)
  ;; This handler is special:
  ;; Since !file is a special node used only at the top of trees
  ;; it produces a single node, and not a nodeset like other handlers.
  (let* ((doc (car l))
	 (styles (cdadr l))
	 (lang (caddr l))
	 (tmpath (cadddr l))
	 (title (tmhtml-find-title doc))
	 (css `(h:style (@ (type "text/css")) ,(tmhtml-css-header)))
	 (body (tmhtml doc)))
    (set! title (cond ((not title) "No title")
		      ((or (in? "tmdoc" styles) (in? "tmweb" styles))
		       `(concat ,(tmhtml-force-string title)
				" (FSF GNU project)"))
		      (else (tmhtml-force-string title))))
    (if (or (in? "tmdoc" styles) (in? "tmweb" styles) (in? "mmxdoc" styles))
	(with ss (if (in? "mmxdoc" styles)
		     "http://www.texmacs.org/css/mmxdoc.css"
		     "http://www.texmacs.org/css/tmdoc.css")
	  (set! css `(h:link (@ (rel "stylesheet")
				(href ,ss)
				(type "text/css"))))
	  (set! body (tmhtml-tmdoc-post body))))
    `(h:html
      (h:head
       (h:title ,@(tmhtml title))
       (h:meta (@ (name "generator")
		  (content ,(string-append "TeXmacs " (texmacs-version)))))
       ,css)
      (h:body ,@body))))

(define (tmhtml-finalize-document top)
  ;; @top must be a node produced by tmhtml-file
  "Prepare a XML document for serialization"
  (define xmlns-attrs
    '((xmlns "http://www.w3.org/1999/xhtml")
      (xmlns:m "http://www.w3.org/1998/Math/MathML")
      (xmlns:x "http://www.texmacs.org/2002/extensions")))
  (define doctype-list
    (let ((html "-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN")
	  (mathml "http://www.w3.org/TR/MathML2/dtd/xhtml-math11-f.dtd"))
      (if tmhtml-mathml? (list html mathml) (list html))))
  `(*TOP* (*PI* xml "version=\"1.0\" encoding=\"UTF-8\"")
	  (*DOCTYPE* html PUBLIC ,@doctype-list)
	  ,((cut sxml-set-attrs <> xmlns-attrs)
	    (sxml-strip-ns-prefix "h" (sxml-strip-ns-prefix "m" top)))))

(define (tmhtml-finalize-selection l)
  ;; @l is a nodeset produced by any handler _but_ tmhtml-file
  "Prepare a HTML node-set for serialization."
  `(*TOP* ,@(map (cut sxml-strip-ns-prefix "h" <>) l)))

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;; Block structures
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(define (tmhtml-document-elem x)
  ;; NOTE: this should not really be necessary, but it improves
  ;; the layout of verbatim environments with a missing block structure
  (if (and (list-2? x)
	   (or (== (car x) 'verbatim) (== (car x) 'code))
	   (not (func? (cadr x) 'document)))
      (tmhtml (list (car x) (list 'document (cadr x))))
      (tmhtml x)))

(define (tmhtml-compute-max-vspace l after?)
  (and (nnull? l)
    (with s1 (tmhtml-compute-vspace (car l) after?)
      (with s2 (tmhtml-compute-max-vspace (cdr l) after?)
	(cond ((not s1) s2)
	      ((not s2) s1)
	      (else
		(with l1 (string->tmlength s1)
		  (with l2 (string->tmlength s2)
		    (if (== (tmlength-unit l1) (tmlength-unit l2))
			(if (>= (tmlength-value l1) (tmlength-value l2)) s1 s2)
			l1 ;; FIXME: do something more subtle here
			)))))))))

(define (tmhtml-compute-vspace x after?)
  (cond ((and (not after?) (func? x 'vspace* 1)) (tmhtml-force-string (cadr x)))
	((and after? (func? x 'vspace 1)) (tmhtml-force-string (cadr x)))
	;;((and (not after?) (func? x 'document)) (tmhtml-compute-vspace (cadr x) #f))
	;;((and after? (func? x 'document)) (tmhtml-compute-vspace (cAr x) #t))
	((func? x 'concat) (tmhtml-compute-max-vspace (cdr x) after?))
	((func? x 'with) (tmhtml-compute-vspace (cAr x) after?))
	;;((func? x 'surround) (tmhtml-compute-max-vspace (cDdr x) after?))
	;;((func? x 'surround) (tmhtml-compute-max-vspace (cdr x) after?))
	(else #f)))

(define (tmhtml-document-p x)
  (let* ((body (tmhtml-document-elem x))
	 (l1 (tmhtml-compute-vspace x #f))
	 (l2 (tmhtml-compute-vspace x #t))
	 (h1 (and l1 (tmlength->htmllength l1 #t)))
	 (h2 (and l2 (tmlength->htmllength l2 #t)))
	 (s1 (and h1 (string-append "margin-top: " h1)))
	 (s2 (and h2 (string-append "margin-bottom: " h2)))
	 (s (cond ((and s1 s2) (string-append s1 "; " s2))
		  (s1 s2)
		  (s2 s1)
		  (else #f))))
    ;;(display* "paragraph= " x "\n")
    ;;(display* "style    = " s "\n")
    (if s `(h:p (@ (style ,s)) ,@body) `(h:p ,@body))))

(define (xtmhtml-document-p x)
  (with body (tmhtml-document-elem x)
    `(h:p ,@body)))

(define (tmhtml-document l)
  (cond ((null? l) '())
	((ahash-ref tmhtml-env :preformatted)
	 (tmhtml-post-simplify-nodes
	  (list-concatenate
	   ((cut list-intersperse <> '("\n"))
	    (map tmhtml l)))))
	(else
	  (tmhtml-post-paragraphs (map tmhtml-document-p l)))))

(define (tmhtml-paragraph l)
  (let rec ((l l))
    (if (null? l) '()
	(let ((h (tmhtml (car l)))
	      (r (rec (cdr l))))
	  (cond ((null? h) r)		; correct when r is null too
		((null? r) h)
		(else `(,@h (h:br) ,@r)))))))

(define (tmhtml-post-paragraphs l)
  ;; Post process a collection of h:p elements
  ;;
  ;; If a h:p contains a h:hN, remove the h:p node and prepend the rest of the
  ;; contents to the next h:p. If the next element, after post processing is
  ;; not a h:p, create an intermediate h:p to hold the data.
  ;;
  ;; If a h:p contains a list element, remove the enclosing h:p. The TeXmacs
  ;; editor ensures that an <item-list> or <desc-list> is the only element
  ;; contained in its enclosing <doc-item>.
  ;;
  ;; If a h:p contains a h:pre element, remove the enclosing h:p. The VERBATIM
  ;; handler ensures that block VERBATIM and CODE environment are alone in the
  ;; paragraph.
  ;;
  ;; NOTE: assumes the heading is at the start of a paragraph. That is
  ;; consistent with the fact that (as of 2003-02-04) the only converted
  ;; invisible markup is <label> and correct usage requires it to be after the
  ;; section title.
  (let rec ((in l) (out '()) (trail #f))
    (let* ((para (and (pair? in) (car in)))
	   (cont (and para (sxml-content para)))
	   (first (and cont (pair? cont) (car cont)))
	   (next (lambda (o t) (rec (cdr in) o t)))
	   (flush (lambda () (if trail `((h:p ,@trail) ,@out) out)))
	   (accept (lambda () (if trail (sxml-prepend para trail) para)))
	   (give (lambda () (and (pair? (cdr cont)) (cdr cont)))))
      ;; invariant: (xor prev prev-trail)
      (cond ((null? in) (reverse (flush)))
	    ((or (null? cont) (string? first))
	     (next (cons (accept) out) #f))
	    ((sxhtml-heading? first)
	     ;; tmhtml-post-heading should be called by concat handler
	     (next (cons first (flush)) (give)))
	    ((sxhtml-list? first)
	     ;; texmacs editor ensures there is no trail after a list
	     (next (append cont (flush)) #f))
	    ((== 'h:pre (sxml-name first))
	     ;; handlers and editor ensure there is no trail after a h:pre
	     (next (append cont (flush)) #f))
	    ((and (sxhtml-table? first) (null? (cdr cont)))
	     ;; if table is not alone, we cannot help but produce bad html
	     ;; if table is alone, drop the enclosing <h:p>
	     (next (append cont (flush)) #f))
	    (else (next (cons (accept) out) #f))))))

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;; Surrounding block structures
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define document-done '())
(define concat-done '())

(define (serialize-print x)
  (set! concat-done (cons x concat-done)))

(define (serialize-paragraph x)
  (serialize-concat x)
  (with l (tmconcat-simplify (reverse concat-done))
    (set! document-done (cons (cons 'concat l) document-done))
    (set! concat-done '())))

(define (serialize-concat x)
  (cond ((in? x '("" (document) (concat))) (noop))
	((func? x 'document)
	 (for-each serialize-paragraph (cDdr x))
	 (serialize-concat (cAr x)))
	((func? x 'concat)
	 (for-each serialize-concat (cdr x)))
	((func? x 'surround 3)
	 (serialize-concat (cadr x))
	 (serialize-concat (cadddr x))
	 (serialize-concat (caddr x)))
	((func? x 'with)
	 (let* ((r (simplify-document (cAr x)))
		(w (lambda (y) `(with ,@(cDdr x) ,y))))
	   (if (not (func? r 'document))
	       (serialize-print (w r))
	       (let* ((head (cadr r))
		      (body `(document ,@(cDr (cddr r))))
		      (tail (cAr r)))
		 (serialize-paragraph (w head))
		 (set! document-done (cons (w body) document-done))
		 (serialize-concat (w tail))))))
	(else (serialize-print x))))

(define (simplify-document x)
  (with-global document-done '()
    (with-global concat-done '()
      (serialize-paragraph x)
      (if (list-1? document-done)
	  (car document-done)
	  (cons 'document (reverse document-done))))))

(define (block-document? x)
  (cond ((func? x 'document) #t)
	((func? x 'concat) (list-any block-document? (cdr x)))
	((func? x 'surround 3) (block-document? (cAr x)))
	((func? x 'with) (block-document? (cAr x)))
	(else #f)))

(define (blockify x)
  (cond ((func? x 'document) x)
	((or (func? x 'surround 3) (func? x 'with))
	 (rcons (cDr x) (blockify (cAr x))))
	(else `(document ,x))))

(define (tmhtml-surround l)
  (let* ((r1 `(surround ,@l))
	 (r2 (simplify-document r1))
	 (f? (and (block-document? r1) (not (func? r2 'document))))
	 (r3 (if f? (blockify r2) r2)))
    (tmhtml r3)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Horizontal concatenations
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-glue-scripts l)
  (cond ((or (null? l) (null? (cdr l))) l)
	((and (func? (car l) 'rsub 1) (func? (cadr l) 'rsup 1))
	 (cons `(rsubsup ,(cadar l) ,(cadadr l))
	       (tmhtml-glue-scripts (cddr l))))
	(else (cons (car l) (tmhtml-glue-scripts (cdr l))))))

(define (heading? l)
  (cond ((null? l) #f)
	((sxhtml-label? (car l)) (heading? (cdr l)))
	((sxhtml-heading? (car l)) #t)
	(else #f)))

(define (tmhtml-post-heading l)
  ;; Post-process the converted result of a concat containing a section title.
  ;;
  ;; Any label preceding the section is moved after it.
  ;;
  ;; The first label after the section is changed to an 'id' attribute in the
  ;; heading element, if it has not already an 'id' attribute.
  ;;
  ;; NOTE: assumes the heading is the first node (not counting labels)
  (receive (labels-before rest) (list-span l sxhtml-label?)
    (receive (heading rest) (car+cdr rest)
      (if (sxml-attr heading 'id)
	  `(,heading ,@labels-before ,@rest)
	  (receive (labels-after rest) (list-partition rest sxhtml-label?)
	    (let ((labels (append labels-before labels-after)))
	      (if (null? labels) l
		  (cons (sxml-prepend (sxhtml-glue-label heading (car labels))
				      (cdr labels))
			rest))))))))

(define (tmhtml-post-table l)
  ;; Post process the converted result of a concat containing a table.
  ;;
  ;; If a label is adjacent to the table, use it to set the table id. If there
  ;; are several labels adjacent to the table, leave all but one label
  ;; untouched. There is no guarantee on which label is glued.
  (define (glue-label-to-table x knil)
    (cond ((null? knil) (list x))
	  ((and (sxhtml-label? x)
		(sxhtml-table? (car knil))
		(not (sxml-attr (car knil) 'id)))
	   (cons (sxhtml-glue-label (car knil) x)
		 (cdr knil)))
	  ((and (sxhtml-table? x)
		(not (sxml-attr x 'id))
		(sxhtml-label? (car knil)))
	   (cons (sxhtml-glue-label x (car knil))
		 (cdr knil)))
	  (else (cons x knil))))
  (list-fold-right glue-label-to-table '() l))

(define (tmhtml-concat l)
  (set! l (tmhtml-glue-scripts l))
  (set! l (tmconcat-structure-tabs l))
  ;; FIXME: tabs which are inside a 'with' are not treated correctly
  (tmhtml-post-simplify-nodes
   (let ((l (tmhtml-list l)))
     (cond ((null? l) '())
	   ((string? (car l)) l)
	   ((heading? l) (tmhtml-post-heading l))
	   ((list-any sxhtml-table? l) (tmhtml-post-table l))
	   ((and (null? (cdr l)) (pair? (car l))
		 (== (caar l) 'h:div) (== (cadar l) '(@ (class "left-tab"))))
	    (cddar l))
	   (else l)))))

(define (tmhtml-align-left l)
  (with r (tmhtml-concat l)
    (if (in? r '(() (""))) '()
	`((h:div (@ (class "left-tab")) ,@r)))))

(define (tmhtml-align-middle l)
  (with r (tmhtml-concat l)
    (if (in? r '(() (""))) '()
	`((h:div (@ (class "center-tab")) ,@r)))))

(define (tmhtml-align-right l)
  (with r (tmhtml-concat l)
    (if (in? r '(() (""))) '()
	`((h:div (@ (class "right-tab")) ,@r)))))

(define (tmhtml-post-simplify-nodes l)
  ;; Catenate adjacent string nodes and remove empty string nodes
  (let rec ((l l))
    (cond ((null? l) '())
	  ((and (string? (car l)) (string-null? (car l)))
	   (rec (cdr l)))
	  ((null? (cdr l)) l)
	  ((and (string? (car l)) (string? (cadr l)))
	   (rec (cons (string-append (car l) (cadr l)) (cddr l))))
	  (else (cons (car l) (rec (cdr l)))))))

(define (tmhtml-post-simplify-element e)
  ;; Simplify the nodes of the element content
  (list (append (sxml-element-head e)
		(tmhtml-post-simplify-nodes (sxml-content e)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Formatting text
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-hspace l)
  (with len (tmlength->htmllength (if (list-1? l) (car l) (cadr l)) #t)
    (if (not len) '()
	`((spacer (@ (type "block")
		     (style ,(string-append "width: " len))))))))

(define (tmhtml-vspace l)
  '())

(define (tmhtml-move l)
  (tmhtml (car l)))

(define (tmhtml-resize l)
  (tmhtml (car l)))

(define (tmhtml-float l)
  (tmhtml (cAr l)))

(define (tmhtml-repeat l)
  (tmhtml (car l)))

(define (tmhtml-datoms l)
  (tmhtml (cAr l)))

(define (tmhtml-new-line l)
  '((h:br)))

(define (tmhtml-next-line l)
  '((h:br)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Mathematics
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-id l)
  (tmhtml (car l)))

(define (tmhtml-big l)
  (cond ((in? (car l) '("sum" "prod" "int" "oint" "amalg"))
	 (tmhtml (string-append "<" (car l) ">")))
	((in? (car l) '("<cap>" "<cup>" "<vee>" "<wedge>"))
	 (with s (substring (car l) 1 (- (string-length (car l)) 1))
	   (tmhtml (string-append "<big" s ">"))))
	((== (car l) ".") '())
	(else (tmhtml (car l)))))

(define (tmhtml-below l)
  `("below (" ,@(tmhtml (car l)) ", " ,@(tmhtml (cadr l)) ")"))

(define (tmhtml-above l)
  `("above (" ,@(tmhtml (car l)) ", " ,@(tmhtml (cadr l)) ")"))

(define (tmhtml-sub l)
  `((h:sub ,@(tmhtml (car l)))))

(define (tmhtml-sup l)
  `((h:sup ,@(tmhtml (car l)))))

(define (tmhtml-subsup l)
  (let* ((sub (tmhtml (car l)))
	 (sup (tmhtml (cadr l)))
	 (r1 `(h:tr (h:td ,@sup)))
	 (r2 `(h:tr (h:td ,@sub))))
    `((h:sub (h:table (@ (class "subsup")) ,r1 ,r2)))))

;;(define (tmhtml-frac l)
;;  (let* ((num (tmhtml (car l)))
;;	 (den (tmhtml (cadr l))))
;;    `("frac (" ,@num ", " ,@den ")")))

(define (tmhtml-frac l)
  (let* ((num (tmhtml (car l)))
	 (den (tmhtml (cadr l)))
	 (n `(h:tr (h:td (@ (style "border-bottom: solid 1px")) ,@num)))
	 (d `(h:tr (h:td ,@den))))
    `((h:table (@ (class "fraction")) ,n ,d))))

(define (tmhtml-sqrt l)
  (if (= (length l) 1)
      `("sqrt (" ,@(tmhtml (car l)) ")")
      `("sqrt" (h:sub ,@(tmhtml (cadr l)))
	" (" ,@(tmhtml (car l)) ")")))

(define (tmhtml-short? l)
  (and (list-1? l)
       (or (string? (car l))
	   (and (func? (car l) 'h:i) (tmhtml-short? (cdar l)))
	   (and (func? (car l) 'h:b) (tmhtml-short? (cdar l)))
	   (and (func? (car l) 'h:u) (tmhtml-short? (cdar l)))
	   (and (func? (car l) 'h:var) (tmhtml-short? (cdar l)))
	   (and (func? (car l) 'h:font) (tmhtml-short? (cdar l))))))

(define (tmhtml-wide l)
  (let* ((body (tmhtml (car l)))
	 (acc (tmhtml (cadr l)))
	 (class (if (in? acc '(("^") ("~"))) "accent" "wide")))
    (if (tmhtml-short? body)
	`(,@body (h:sup (@ (class ,class)) ,@acc))
	`("(" ,@body ")" (h:sup ,@acc)))))

(define (tmhtml-neg l)
  `("not(" ,@(tmhtml (car l)) ")"))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Color conversions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmcolor->htmlcolor x)
  (with s (tmhtml-force-string x)
    (cond ((== s "light grey") "#d0d0d0")
	  ((== s "dark grey") "#707070")
	  ((== s "dark red") "#800000")
	  ((== s "dark green") "#008000")
	  ((== s "dark blue") "#000080")
	  ((== s "dark yellow") "#808000")
	  ((== s "dark magenta") "#800080")
	  ((== s "dark cyan") "#008080")
	  ((== s "dark orange") "#804000")
	  ((== s "dark brown") "#401000")
	  ((== s "broken white") "#ffffdf")
	  ((== s "pastel red") "#ffdfdf")
	  ((== s "pastel green") "#dfffdf")
	  ((== s "pastel blue") "#dfdfff")
	  ((== s "pastel yellow") "#ffffdf")
	  ((== s "pastel magenta") "#ffdfff")
	  ((== s "pastel cyan") "#dfffff")
	  ((== s "pastel orange") "#ffdfbf")
	  ((== s "pastel brown") "#dfbfbf")
	  (else s))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Length conversions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define-table tmhtml-length-table
  ("mm" . 0.1)
  ("cm" . 1.0)
  ("in" . 2.54)
  ("pt" . 3.514598e-2)
  ("tmpt" . 2.7457797e-5)
  ("fn" . 0.4)
  ("em" . 0.4)
  ("ex" . 0.2)
  ("spc" . 0.2)
  ("pc" . 0.42175)
  ("par" . 16)
  ("pag" . 12)
  ("px" . 0.025)
  ("ln" . 0.025))

(define (make-exact x)
  (number->string (inexact->exact x)))

(define (number->htmlstring x)
  (number->string (if (exact? x)
		      (if (integer? x) x (exact->inexact x))
		      (if (and (integer? (inexact->exact x))
			       (= x (exact->inexact (inexact->exact x))))
			  (inexact->exact x) x))))

(define (tmlength->htmllength len css?)
  (and-let* ((len-str (tmhtml-force-string len))
	     (tmlen (string->tmlength len-str))
	     (dummy2? (not (tmlength-null? tmlen)))
	     (val (tmlength-value tmlen))
	     (unit (symbol->string (tmlength-unit tmlen)))
	     (incm (ahash-ref tmhtml-length-table unit))
	     (cmpx (/ 1 (ahash-ref tmhtml-length-table "px"))))
    (cond ((== unit "px") (number->htmlstring val))
	  ((in? unit '("par" "pag"))
	   (string-append (number->htmlstring (* 100 val)) "%"))
	  ((and css? (== unit "tmpt"))
	   (string-append (number->htmlstring (* cmpx val incm)) "px"))
	  ((and css? (== unit "fn"))
	   (string-append (number->htmlstring val) "em"))
	  ((and css? (== unit "spc"))
	   (string-append (number->htmlstring (/ val 2)) "em"))
	  ((and css? (== unit "ln"))
	   (string-append (number->htmlstring val) "px"))
	  (css? len)
	  (else (number->htmlstring (* cmpx val incm))))))

(define (tmlength->px len)
  (and-let* ((tmlen (string->tmlength len))
	     (dummy? (not (tmlength-null? tmlen)))
	     (val (tmlength-value tmlen))
	     (unit (symbol->string (tmlength-unit tmlen)))
	     (incm (ahash-ref tmhtml-length-table unit))
	     (cmpx (/ 1 (ahash-ref tmhtml-length-table "px"))))
    (* cmpx val incm)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Local environment changes
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-with-mode val arg)
  (ahash-with tmhtml-env :math (== val "math")
    (tmhtml (if (== val "prog") `(verbatim ,arg) arg))))

(define (tmhtml-with-color val arg)
  `((h:font (@ (color ,(tmcolor->htmlcolor val))) ,@(tmhtml arg))))

(define (tmhtml-with-font-size val arg)
  (ahash-with tmhtml-env :mag val
    (let* ((x (* (string->number val) 100))
	   (s (cond ((< x 1) "-4") ((< x 55) "-4") ((< x 65) "-3")
		    ((< x 75) "-2") ((< x 95) "-1") ((< x 115) "0")
		    ((< x 135) "+1") ((< x 155) "+2") ((< x 185) "+3")
		    ((< x 225) "+4") ((< x 500) "+5") (else "+5"))))
      (if s `((h:font (@ (size ,s)) ,@(tmhtml arg))) (tmhtml arg)))))

(define (tmhtml-with-block style arg)
  (with r (tmhtml (blockify arg))
    (if (in? r '(() ("") ((h:p)) ((h:p "")))) '()
	`((h:div (@ (style ,style)) ,@r)))))

(define (tmhtml-with-par-left val arg)
  (with x (tmlength->px val)
    (if (not x) (tmhtml arg)
	(with d (- x (ahash-ref tmhtml-env :left-margin))
	  (with s (string-append "margin-left: " (number->htmlstring d) "px")
	    (ahash-with tmhtml-env :left-margin x
	      (tmhtml-with-block s arg)))))))

(define (tmhtml-with-par-right val arg)
  (with x (tmlength->px val)
    (if (not x) (tmhtml arg)
	(with d (- x (ahash-ref tmhtml-env :right-margin))
	  (with s (string-append "margin-right: " (number->htmlstring d) "px")
	    (ahash-with tmhtml-env :right-margin x
	      (tmhtml-with-block s arg)))))))

(define (tmhtml-with-par-first val arg)
  (with x (tmlength->htmllength val #t)
    (if (not x) (tmhtml arg)
	(with s (string-append "text-indent: " x)
	  (tmhtml-with-block s arg)))))

(define (tmhtml-with-par-par-sep val arg)
  (with x (tmlength->px val)
    (if (== (inexact->exact x) 0)
	`((h:div (@ (class "compact-block")) ,@(tmhtml arg)))
	(tmhtml arg))))

(define (tmhtml-with-one var val arg)
  (cond ((drd-ref tmhtml-with-cmd% (list var val)) =>
	 (lambda (w) (list (append w (tmhtml arg)))))
	((drd-ref tmhtml-with-cmd% var) =>
	 (lambda (h) (h val arg)))
	(else (tmhtml arg))))

(define (tmhtml-force-string x)
  (cond ((string? x) x)
	((func? x 'quote 1) (tmhtml-force-string (cadr x)))
	((func? x 'tmlen 1)
	 (string-append (tmhtml-force-string (cadr x)) "tmpt"))
	((func? x 'tmlen 3)
	 (string-append (tmhtml-force-string (caddr x)) "tmpt"))
	;;(else (force-string x))))
	(else (texmacs->verbatim (tm->tree x)))))

(define (tmhtml-with l)
  (cond ((null? l) '())
	((null? (cdr l)) (tmhtml (car l)))
	((null? (cddr l)) '())
	((func? (cAr l) 'graphics) (tmhtml-png (cons 'with l)))
	(else
	 (let* ((var (tmhtml-force-string (car l)))
		(val (tmhtml-force-string (cadr l)))
		(next (cddr l)))
	   (tmhtml-with-one var val `(with ,@next))))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Other macro-related primitives
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-compound l)
  ;; Explicit expansions are converted and handled as implicit expansions.
  (tmhtml-implicit-compound (cons (string->symbol (car l)) (cdr l))))

(define (tmhtml-mark l)
  ;; Explicit expansions are converted and handled as implicit expansions.
  (tmhtml (cadr l)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Source code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (blue sym)
  `(h:font (@ (color "blue")) ,sym))

(define (tmhtml-src-args l)
  (if (null? l) l
      `(,(blue "|")
	,@(tmhtml (car l))
	,@(tmhtml-src-args (cdr l)))))

(define (tmhtml-inline-tag l)
  `(,(blue "&lt;")
    ,@(tmhtml (car l))
    ,@(tmhtml-src-args (cdr l))
    ,(blue "&gt;")))

(define (tmhtml-open-tag l)
  `(,(blue "&lt;\\")
    ,@(tmhtml (car l))
    ,@(tmhtml-src-args (cdr l))
    ,(blue "|")))

(define (tmhtml-middle-tag l)
  `(,@(tmhtml-src-args (cdr l))
    ,(blue "|")))

(define (tmhtml-close-tag l)
  `(,@(tmhtml-src-args (cdr l))
    ,(blue "&gt;")))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Other primitives
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-label l)
  ;; WARNING: bad conversion if ID is not a string.
  `((h:a (@ (id ,(cork->html (force-string (car l))))))))

;(define (tmhtml-reference l)
;  (list 'ref (cork->html (force-string (car l)))))

;(define (tmhtml-pageref l)
;  (list 'pageref (cork->html (force-string (car l)))))

(define (tmhtml-suffix s)
  ;; Change .tm suffix to .xhtml suffix for local files for correct
  ;; conversion of entire web-sites. We might create an option
  ;; in order to disable this suffix change
  (let* ((sdir (string-rindex s #\/))
	 (sep (string-rindex s #\#)))
    (cond ((or (string-starts? s "http:") (string-starts? s "ftp:")) s)
          ((and sep (or (not sdir) (< sdir sep)))
	   (string-append (tmhtml-suffix (substring s 0 sep))
			  (string-drop s sep)))
	  ((string-ends? s ".tm")
	   (string-append (string-drop-right s 3)
			  (if tmhtml-mathml? ".xhtml" ".html")))
	  ((string-ends? s ".texmacs")
	   (string-append (string-drop-right s 8) ".tm"))
	  (else s))))

(define (tmhtml-hyperlink l)
  ;; WARNING: bad conversion if URI is not a string.
  ;; TODO: change label at start of content into ID attribute, move other
  ;; labels out (A elements cannot be nested!).
  (let* ((body (tmhtml (first l)))
	 (to (cork->html (force-string (second l)))))
    (if (string-starts? to "$")
	body ;; temporary fix for URLs like $TEXMACS_PATH/...
	`((h:a (@ (href ,(tmhtml-suffix to))) ,@body)))))

(define (tmhtml-specific l)
  (cond ((== (car l) "html") (list (string-decode (force-string (cadr l)))))
	((== (car l) "image") (tmhtml-png (cadr l)))
	(else '())))

(define (tmhtml-action l)
  `((h:u ,@(tmhtml (car l)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Tables
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (map* fun l)
  (list-filter (map fun l) identity))

(define (html-css-attrs l)
  ;; l is a list of either key-value lists (XML) or strings (CSS)
  ;; we return a list with the corresponding @-style attribute
  (if (null? l) '()
      (receive (css html) (list-partition l string?)
	(if (nnull? css)
	    (with style (apply string-append (list-intersperse css "; "))
	      (set! html (cons `(style ,style) html))))
	`((@ ,@html)))))

(define (length-attr what x . opt)
  (with len (tmlength->htmllength x #t)
    (and len (apply string-append (cons* what ": " len opt)))))

(define (border-attr what x)
  (length-attr what x " solid"))

(define (tmhtml-make-cell-attr x)
  (cond ((== (car x) "cell-width") (length-attr "width" (cadr x)))
	((== (car x) "cell-height") (length-attr "height" (cadr x)))
	((== x '("cell-halign" "l")) "text-align: left")
	((== x '("cell-halign" "c")) "text-align: center")
	((== x '("cell-halign" "r")) "text-align: right")
	((== x '("cell-valign" "t")) "vertical-align: top")
	((== x '("cell-valign" "c")) "vertical-align: middle")
	((== x '("cell-valign" "b")) "vertical-align: bottom")
	((== x '("cell-valign" "B")) "vertical-align: baseline")
	((== (car x) "cell-background")
	 `(bgcolor ,(tmcolor->htmlcolor (cadr x))))
	((== (car x) "cell-lborder") (border-attr "border-left" (cadr x)))
	((== (car x) "cell-rborder") (border-attr "border-right" (cadr x)))
	((== (car x) "cell-tborder") (border-attr "border-top" (cadr x)))
	((== (car x) "cell-bborder") (border-attr "border-bottom" (cadr x)))
	((== (car x) "cell-lsep") (length-attr "padding-left" (cadr x)))
	((== (car x) "cell-rsep") (length-attr "padding-right" (cadr x)))
	((== (car x) "cell-tsep") (length-attr "padding-top" (cadr x)))
	((== (car x) "cell-bsep") (length-attr "padding-bottom" (cadr x)))
	(else #f)))

(define (tmhtml-make-cell c cellf)
  (ahash-with tmhtml-env :left-margin 0
    `(h:td ,@(html-css-attrs (map* tmhtml-make-cell-attr cellf))
	   ,@(tmhtml (cadr c)))))

(define (tmhtml-make-cells-bis l cellf)
  (if (null? l) l
      (cons (tmhtml-make-cell (car l) (car cellf))
	    (tmhtml-make-cells-bis (cdr l) (cdr cellf)))))

(define (tmhtml-width-part attrl)
  (cond ((null? attrl) 0)
	((== (caar attrl) "cell-hpart") (string->number (cadar attrl)))
	(else (tmhtml-width-part (cdr attrl)))))

(define (tmhtml-width-replace attrl sum)
  (with part (tmhtml-width-part attrl)
    (if (== part 0) attrl
	(with l (list-filter attrl (lambda (x) (!= (car x) "cell-width")))
	  (with w (number->htmlstring (/ part sum))
	    (cons (list "cell-width" (string-append w "par")) l))))))

(define (tmhtml-make-cells l cellf)
  (let* ((partl (map tmhtml-width-part cellf))
	 (sum (apply + partl)))
    (if (!= sum 0) (set! cellf (map (cut tmhtml-width-replace <> sum) cellf)))
    (tmhtml-make-cells-bis l cellf)))

(define (tmhtml-make-row-attr x)
  (tmhtml-make-cell-attr x))

(define (tmhtml-make-row r rowf cellf)
  `(h:tr ,@(html-css-attrs (map* tmhtml-make-row-attr rowf))
	 ,@(tmhtml-make-cells (cdr r) cellf)))

(define (tmhtml-make-rows l rowf cellf)
  (if (null? l) l
      (cons (tmhtml-make-row  (car l) (car rowf) (car cellf))
	    (tmhtml-make-rows (cdr l) (cdr rowf) (cdr cellf)))))

(define (tmhtml-make-column-attr x)
  (tmhtml-make-cell-attr x))

(define (tmhtml-make-col colf)
  `(h:col ,@(html-css-attrs (map* tmhtml-make-column-attr colf))))

(define (tmhtml-make-column-group colf)
  (if (list-every null? colf) '()
      `((h:colgroup ,@(map tmhtml-make-col colf)))))

(define (tmhtml-make-table-attr x)
  (cond ((== (car x) "table-width") (length-attr "width" (cadr x)))
	((== (car x) "table-height") (length-attr "height" (cadr x)))
	((== (car x) "table-lborder") (border-attr "border-left" (cadr x)))
	((== (car x) "table-rborder") (border-attr "border-right" (cadr x)))
	((== (car x) "table-tborder") (border-attr "border-top" (cadr x)))
	((== (car x) "table-bborder") (border-attr "border-bottom" (cadr x)))
	((== (car x) "table-lsep") (length-attr "padding-left" (cadr x)))
	((== (car x) "table-rsep") (length-attr "padding-right" (cadr x)))
	((== (car x) "table-tsep") (length-attr "padding-top" (cadr x)))
	((== (car x) "table-bsep") (length-attr "padding-bottom" (cadr x)))
	(else #f)))

(define (tmhtml-make-table t tablef colf rowf cellf)
  (let* ((attrs (map* tmhtml-make-table-attr tablef))
	 (em (- (* (tmtable-rows t) 0.55)))
	 (va (string-append "vertical-align: " (number->htmlstring em) "em")))
    (if (not (list-find attrs (cut == <> "width: 100%")))
	(set! attrs (cons* "display: inline" va attrs)))
    `(h:table ,@(html-css-attrs attrs)
	      ,@(tmhtml-make-column-group colf)
	      (h:tbody ,@(tmhtml-make-rows (cdr t) rowf cellf)))))

(define (tmhtml-table l)
  (list (tmhtml-make-table (cons 'table l) '() '() '() '())))

(define (tmhtml-tformat l)
  (with t (tmtable-normalize (cons 'tformat l))
    (receive (tablef colf rowf cellf) (tmtable-properties* t)
      (list (tmhtml-make-table (cAr t) tablef colf rowf cellf)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Pictures
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-collect-labels x)
  (cond ((nlist? x) '())
	((and (func? x 'label 1) (string? (cadr x))) `((id ,(cadr x))))
	(else (append-map tmhtml-collect-labels (cdr x)))))

(define (tmhtml-png-names)
  (set! tmhtml-image-serial (+ tmhtml-image-serial 1))
  (let* ((postfix (string-append
		   "-" (number->string tmhtml-image-serial) ".png"))
	 (name-url (url-glue tmhtml-image-root-url postfix))
	 (name-string (string-append tmhtml-image-root-string postfix)))
    (values name-url name-string)))

(define (tmhtml-png y)
  (let* ((mag (ahash-ref tmhtml-env :mag))
	 (x (if (or (nstring? mag) (== mag "1")) y
		`(with "font-size" ,mag ,y)))
	 (l1 (tmhtml-collect-labels y))
	 (l2 (if (null? l1) l1 (list (car l1)))))
    (with cached (ahash-ref tmhtml-image-cache x)
      (if (not cached)
	  (receive (name-url name-string) (tmhtml-png-names)
	    ;;(display* x " -> " name-url ", " name-string "\n")
	    (let* ((extents (print-snippet name-url x))
		   ;;(pixels (inexact->exact (/ (second extents) 2100)))
		   (pixels (inexact->exact (/ (second extents) 2000)))
		   (valign (number->htmlstring pixels))
		   (style (string-append "vertical-align: " valign "px")))
	      ;;(display* x " -> " extents "\n")
	      (set! cached
		    `((h:img (@ (src ,name-string) (style ,style) ,@l2))))
	      (ahash-set! tmhtml-image-cache x cached)))
	  cached))))

(define (tmhtml-graphics l)
  (tmhtml-png (cons 'graphics l)))

(define (tmhtml-postscript-name name)
  (with u (url-relative current-save-target (string->url name))
    (if (and (or (string-ends? name ".ps") (string-ends? name ".eps"))
	     (url-exists? u))
	(receive (name-url name-string) (tmhtml-png-names)
	  (system-2 "convert" u name-url)
	  name-string)
	name)))

(define (tmhtml-postscript l)
  ;; FIXME: Should also test that width and height are not magnifications.
  ;; Currently, magnifications make tmlength->htmllength return #f.
  (if (nstring? (first l))
      (tmhtml-png (cons 'postscript l))
      (let* ((s (tmhtml-postscript-name (cork->html (first l))))
	     (w (tmlength->htmllength (second l) #f))
	     (h (tmlength->htmllength (third l) #f)))
	`((h:img (@ (src ,s)
		    ,@(if w `((width ,w)) '())
		    ,@(if h `((height ,h)) '())))))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Standard markup
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-list-document list-doc)
  ;; Convert a list-document to a list of <h:li> elements.
  ;; WARNING: makes the xpath environment inconsistent
  (define (item->li mark item)
    (cond ((null? item) '(h:li))
	  ((null? (cdr item)) `(h:li ,@(tmhtml (car item))))
	  (else `(h:li ,@(tmhtml `(document ,@item))))))
  (if (null? (cdr list-doc)) '((h:li))
      (stm-list-map item->li
		    (lambda (x) (== x '(item)))
		    (cdr list-doc))))

;; TODO: when the first data of the list is a label, it must be used to set the
;; ID attribute of the resulting xhtml element. When that is done, remove the
;; warning comment from htmltm-handler.

(define (tmhtml-itemize args)
  `((h:ul ,@(tmhtml-list-document (car args)))))

(define (tmhtml-enumerate args)
  `((h:ol ,@(tmhtml-list-document (car args)))))

(define (tmhtml-desc-document desc-doc)
  ;; WARNING: makes the xpath environment inconsistent
  (define (item->dt-dd mark item)
    (let ((html-item (if (null? (cdr item))
			 (tmhtml (car item))
			 (tmhtml `(document ,@item)))))
      (append
       (if mark (tmhtml mark) '())
       (cond ((and (null? html-item) mark) '())
	     ((null? html-item) '((h:dd)))
	     (else `((h:dd ,@html-item)))))))
  (if (null? (cdr desc-doc)) '((h:dd))
      (apply append (stm-list-map item->dt-dd
				  (lambda (x) (func? x 'item* 1))
				  (cdr desc-doc)))))

(define (tmhtml-description args)
  `((h:dl ,@(tmhtml-desc-document (car args)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Verbatim
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-verbatim args)
  ;; Block-level verbatim environments should only contain inline elements.
  ;;
  ;; @args should be a single element list, we will call this element @body.
  ;;
  ;; If @body is a block structure, it will be either:
  ;; -- a simple DOCUMENT (normal case), and @(tmhtml body) will produce a list
  ;;    of h:p elements;
  ;; -- a block structure producing a single element (degenerate case).
  ;;
  ;; Verbatim structures which do not contain a DOCUMENT but are direct
  ;; children of a DOCUMENT (i.e. they occupy a whole paragraph) are degenerate
  ;; cases of block-level verbatim and must be exported as PRE.
  ;;
  ;; Inline verbatim has little special significance for display in TeXmacs. In
  ;; LaTeX it is used to escape special characters (and protect multiple inline
  ;; spaces, yuck!), but in TeXmacs there is no such problem.
  (with body (first args)
    (if (stm-block-structure? body)
	(verbatim-pre
	 (ahash-with tmhtml-env :preformatted #t
		     (tmhtml body)))
	(verbatim-tt (tmhtml body)))))

(define (verbatim-tt content)
  `((h:tt (@ (class "verbatim")) ,@content)))

(define (verbatim-pre content)
  `((h:pre (@ (class "verbatim") (xml:space "preserve")) ,@content)))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Additional tags
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-doc-title-block l)
  `((h:table (@ (class "title-block"))
	     (h:tr (h:td ,@(tmhtml (car l)))))))

(define (tmhtml-equation* l)
  (with first (simplify-document (car l))
    (with x `(with "mode" "math" (with "math-display" "true" ,first))
      `((h:center ,@(tmhtml x))))))

(define (tmhtml-equation-lab l)
  (with first (simplify-document (car l))
    (with x `(with "mode" "math" (with "math-display" "true" ,first))
      `((h:table (@ (width "100%"))
		 (h:tr (h:td (@ (align "center") (width "100%"))
			     ,@(tmhtml x))
		       (h:td (@ (align "right"))
			     "(" ,@(tmhtml (cadr l)) ")")))))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Tmdoc tags
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-make-block content)
  (let* ((l '(h:td
	      (@ (align "left"))
	      (h:img (@ (src "http://www.texmacs.org/Images/tm_gnu1b.png")))))
	 (c `(h:td
	      (@ (align "center") (width "100%"))
	      ,@(tmhtml content)))
	 (r '(h:td
	      (@ (align "right"))
	      (h:img (@ (src "http://www.texmacs.org/Images/tm_gnu2b.png")))))
	 (row `(h:tr ,l ,c ,r)))
    `(h:table (@ (width "100%") (cellspacing "0") (cellpadding "3")) ,row)))

(define (tmhtml-tmdoc-title l)
  (list `(h:div (@ (class "tmdoc-title-1"))
		,(tmhtml-make-block (car l)))))

(define (tmhtml-tmdoc-title* l)
  (list `(h:div (@ (class "tmdoc-title-2"))
		,(tmhtml-make-block (car l)))
	`(h:div (@ (class "tmdoc-navbar")) ,@(tmhtml (cadr l)))))

(define (tmhtml-tmdoc-title** l)
  (list `(h:div (@ (class "tmdoc-navbar")) ,@(tmhtml (car l)))
	`(h:div (@ (class "tmdoc-title-3")) ,(tmhtml-make-block (cadr l)))
	`(h:div (@ (class "tmdoc-navbar")) ,@(tmhtml (caddr l)))))

(define (tmhtml-tmdoc-flag l)
  ;(tmhtml (car l)))
  (list `(h:div (@ (class "tmdoc-flag")) ,@(tmhtml (car l)))))

(define (tmhtml-tmdoc-copyright* l)
  (if (null? l) l
      `(", " ,@(tmhtml (car l)) ,@(tmhtml-tmdoc-copyright* (cdr l)))))

(define (tmhtml-tmdoc-copyright l)
  (with content
      `("&copy;" " " ,@(tmhtml (car l))
	" " ,@(tmhtml (cadr l))
	,@(tmhtml-tmdoc-copyright* (cddr l)))
    (list `(h:div (@ (class "tmdoc-copyright")) ,@content))))

(define (tmhtml-tmdoc-license l)
  (list `(h:div (@ (class "tmdoc-license")) ,@(tmhtml (car l)))))

(define (tmhtml-key l)
  `((h:u (h:tt ,@(tmhtml (car l))))))

(define (tmhtml-tmdoc-bar? y)
  (or (func? y 'h:h1)
      (func? y 'h:h2)
      (and (func? y 'h:div)
	   (nnull? (cdr y))
	   (func? (cadr y) '@ 1)
	   (== (first (cadadr y)) 'class)
	   (string-starts? (second (cadadr y)) "tmdoc"))))

(define (tmhtml-tmdoc-post-sub x)
  ;; FIXME: these rewritings are quite hacky;
  ;; better simplification would be nice...
  (cond ((and (func? x 'h:p) (list-find (cdr x) tmhtml-tmdoc-bar?)) (cdr x))
	((func? x 'h:p)
	 (with r (append-map tmhtml-tmdoc-post-sub (cdr x))
	   (if (== (cdr x) r) (list x) r)))
	(else (list x))))

(define (tmhtml-tmdoc-post body)
  (with r (append-map tmhtml-tmdoc-post-sub body)
    `((h:div (@ (class "tmdoc-body")) ,@r))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Main conversion routines
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define (tmhtml-list l)
  (append-map tmhtml l))

(define (tmhtml-dispatch htable l)
  (let ((x (drd-ref ,htable (car l))))
    (cond ((not x) #f)
	  ((procedure? x) (x (cdr l)))
	  (else (tmhtml-post-simplify-element
		 (append x (tmhtml-list (cdr l))))))))

(define (tmhtml-implicit-compound l)
  (or (tmhtml-dispatch 'tmhtml-stdmarkup% l)
      '()))

(tm-define (tmhtml-root x)
  (ahash-with tmhtml-env :mag "1"
    (ahash-with tmhtml-env :math #f
      (ahash-with tmhtml-env :preformatted #f
	(ahash-with tmhtml-env :left-margin 0
	  (ahash-with tmhtml-env :right-margin 0
	    (tmhtml x)))))))

(define (tmhtml x)
  ;; Main conversion function.
  ;; Takes a TeXmacs tree in Scheme notation and produce a SXML node-set.
  ;; All handler functions have a similar prototype.
  (cond ((and tmhtml-mathml? (ahash-ref tmhtml-env :math))
	 `((m:math (@ (xmlns "http://www.w3.org/1998/Math/MathML"))
		   ,(texmacs->mathml x tmhtml-env))))
	((and tmhtml-images? (ahash-ref tmhtml-env :math))
	 (tmhtml-png `(with "mode" "math" ,x)))
	((string? x)
	 (if (string-null? x) '() (tmhtml-text x))) ; non-verbatim string nodes
	(else (or (tmhtml-dispatch 'tmhtml-primitives% x)
		  (tmhtml-implicit-compound x)))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Dispatching
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(drd-dispatcher tmhtml-primitives%
  (document tmhtml-document)
  (para tmhtml-paragraph)
  (surround tmhtml-surround)
  (concat tmhtml-concat)
  (format tmhtml-noop)
  (hspace tmhtml-hspace)
  (vspace* tmhtml-vspace)
  (vspace tmhtml-vspace)
  (space tmhtml-hspace)
  (htab tmhtml-hspace)
  (split tmhtml-noop)
  (move tmhtml-move)
  (resize tmhtml-resize)
  (float tmhtml-float)
  (repeat tmhtml-repeat)
  (datoms tmhtml-datoms)
  (dlines tmhtml-datoms)
  (dpages tmhtml-datoms)
  (dbox tmhtml-datoms)

  (with-limits tmhtml-noop)
  (line-break tmhtml-noop)
  (new-line tmhtml-new-line)
  (line-sep tmhtml-noop)
  (next-line tmhtml-next-line)
  (no_break tmhtml-noop)
  (no-indent tmhtml-noop)
  (yes-indent tmhtml-noop)
  (no-indent* tmhtml-noop)
  (yes-indent* tmhtml-noop)
  (page-break* tmhtml-noop)
  (page-break tmhtml-noop)
  (no-page-break* tmhtml-noop)
  (no-page-break tmhtml-noop)
  (new-page* tmhtml-noop)
  (new-page tmhtml-noop)
  (new-dpage* tmhtml-noop)
  (new-dpage tmhtml-noop)

  (group tmhtml-id)
  (left tmhtml-id)
  (mid tmhtml-id)
  (right tmhtml-id)
  (big tmhtml-big)
  (lprime tmhtml-id)
  (rprime tmhtml-id)
  (below tmhtml-below)
  (above tmhtml-above)
  (lsub tmhtml-sub)
  (lsup tmhtml-sup)
  (rsub tmhtml-sub)
  (rsup tmhtml-sup)
  (rsubsup tmhtml-subsup)
  (frac tmhtml-frac)
  (sqrt tmhtml-sqrt)
  (wide tmhtml-wide)
  (neg tmhtml-neg)
  ((:or tree old-matrix old-table old-mosaic old-mosaic-item)
   tmhtml-noop)
  (table tmhtml-table)
  (tformat tmhtml-tformat)
  ((:or twith cwith tmarker row cell sub-table) tmhtml-noop)

  (assign tmhtml-noop)
  (with tmhtml-with)
  (provides tmhtml-noop)
  ((:or value quote-value) tmhtml-compound)
  ((:or macro drd-props arg quote-arg) tmhtml-noop)
  (compound tmhtml-compound)
  ((:or xmacro get-label get-arity map-args eval-args) tmhtml-noop)
  (mark tmhtml-mark)
  (eval tmhtml-noop)
  ((:or if if* case while for-each extern include use-package) tmhtml-noop)
  
  ((:or or xor and not plus minus times over div mod merge length range
	number date translate is-tuple look-up equal unequal less lesseq
	greater greatereq if case while extern authorize)
   tmhtml-noop)

  ((:or style-with style-with* style-only style-only*
	active active* inactive inactive* rewrite-inactive) tmhtml-noop)
  (inline-tag tmhtml-inline-tag)
  (open-tag tmhtml-open-tag)
  (middle-tag tmhtml-middle-tag)
  (close-tag tmhtml-close-tag)
  (symbol tmhtml-noop)
  (latex tmhtml-noop)
  (hybrid tmhtml-noop)

  ((:or tuple collection associate) tmhtml-noop)
  (label tmhtml-label)
  (reference tmhtml-noop)
  (pageref tmhtml-noop)
  (write tmhtml-noop)
  (specific tmhtml-specific)
  (hlink tmhtml-hyperlink)
  (action tmhtml-action)
  ((:or tag meaning) tmhtml-noop)
  ((:or switch fold exclusive progressive superposed) tmhtml-noop)
  (graphics tmhtml-graphics)
  ((:or point line arc bezier) tmhtml-noop)
  (postscript tmhtml-postscript)

  (!file tmhtml-file))

(drd-table tmhtml-stdmarkup%
  ;; special auxiliary tags
  (!left ,tmhtml-align-left)
  (!middle ,tmhtml-align-middle)
  (!right ,tmhtml-align-right)
  ;; Sectioning
  (chapter-title (h:h1))
  (section-title (h:h2))
  (subsection-title (h:h3))
  (subsubsection-title (h:h4))
  (paragraph-title (h:h5))
  (subparagraph-title (h:h6))
  ;; Lists
  ((:or itemize itemize-minus itemize-dot itemize-arrow)
   ,tmhtml-itemize)
  ((:or enumerate enumerate-numeric enumerate-roman enumerate-Roman
	enumerate-alpha enumerate-Alpha)
   ,tmhtml-enumerate)
  ((:or description description-compact description-dash
	description-align description-long)
   ,tmhtml-description)
  (item* (h:dt))
  ;; Phrase elements
  (strong (h:strong))
  (em (h:em))
  (dfn (h:dfn))
  (code* (h:code))
  (samp (h:samp)) ; WARNING: semantic documentation does not match HTML4
  (kbd (h:kbd))
  (var (h:var))
  (abbr (h:abbr))
  (acronym (h:acronym))
  (verbatim ,tmhtml-verbatim)
  (code ,tmhtml-verbatim)
  ;; Presentation
  (tt (h:tt))
  (hrule (h:hr))
  ;; Names
  (TeXmacs ,(lambda x '("TeXmacs")))
  (TeX ,(lambda x '("TeX")))
  (LaTeX ,(lambda x '("LaTeX")))
  ;; additional tags
  (hidden-title ,tmhtml-noop)
  (doc-title-block ,tmhtml-doc-title-block)
  (equation* ,tmhtml-equation*)
  (equation-lab ,tmhtml-equation-lab)
  (equations-base ,tmhtml-equation*)
  ;; tmdoc tags
  (tmdoc-title ,tmhtml-tmdoc-title)
  (tmdoc-title* ,tmhtml-tmdoc-title*)
  (tmdoc-title** ,tmhtml-tmdoc-title**)
  (tmdoc-flag ,tmhtml-tmdoc-flag)
  (tmdoc-copyright ,tmhtml-tmdoc-copyright)
  (tmdoc-license ,tmhtml-tmdoc-license)
  (key ,tmhtml-key)
  (hyper-link ,tmhtml-hyperlink))

;;    (name (h:name)) ; not in HTML4
;;    (person (h:person)))) ; not in HTML4

(drd-table tmhtml-with-cmd%
  ("mode" ,tmhtml-with-mode)
  ("color" ,tmhtml-with-color)
  ("font-size" ,tmhtml-with-font-size)
  ("par-left" ,tmhtml-with-par-left)
  ("par-right" ,tmhtml-with-par-right)
  ("par-first" ,tmhtml-with-par-first)
  ("par-par-sep" ,tmhtml-with-par-par-sep)
  (("font-family" "tt") (h:tt))
  (("font-family" "ss") (h:class (@ (style "font-family: sans-serif"))))
  (("font-series" "bold") (h:b))
  (("font-shape" "italic") (h:i))
  (("font" "roman") (h:class (@ (style "font-family: Times New Roman"))))
  (("font" "times") (h:class (@ (style "font-family: Times New Roman"))))
  (("font" "helvetica") (h:class (@ (style "font-family: Helvetica"))))
  (("font" "courier") (h:class (@ (style "font-family: Coutier"))))
  (("math-font" "cal") (h:class (@ (style "font-family: Flemish Script"))))
  (("math-font" "frak") (h:class (@ (style "font-family: Bernhard Modern"))))
  (("font-series" "medium") (h:class (@ (style "font-weight: normal"))))
  (("font-shape" "right") (h:class (@ (style "font-style: normal"))))
  (("font-shape" "small-caps")
   (h:class (@ (style "font-variant: small-caps")))))

(drd-table tmhtml-with-cmd% ; deprecated
  (("par-mode" "left") (h:div (@ (align "left"))))
  (("par-mode" "justify") (h:div (@ (align "justify"))))
  (("par-mode" "center") (h:center)))

(drd-table tmhtml-with-cmd% ; netscape4
  (("par-columns" "1") (h:multicol (@ (cols "1"))))
  (("par-columns" "2") (h:multicol (@ (cols "2"))))
  (("par-columns" "3") (h:multicol (@ (cols "3"))))
  (("par-columns" "4") (h:multicol (@ (cols "4"))))
  (("par-columns" "5") (h:multicol (@ (cols "5")))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Interface
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(tm-define (texmacs->html x opts)
  (if (tmfile? x)
      (let* ((body (tmfile-extract x 'body))
	     (style* (tmfile-extract x 'style))
	     (style (if (list? style*) style* (list style*)))
	     (lan (tmfile-init x "language"))
	     (doc (list '!file body style lan (get-texmacs-path))))
	(texmacs->html doc opts))
      (begin
	(tmhtml-initialize opts)
	((if (func? x '!file)
	     tmhtml-finalize-document
	     tmhtml-finalize-selection)
	 (tmhtml-root x)))))
