;;;; backend-documentation-lib.scm -- Functions for backend documentation
;;;;
;;;; source file of the GNU LilyPond music typesetter
;;;; 
;;;; (c) 2000--2006 Han-Wen Nienhuys <hanwen@cs.uu.nl>
;;;; Jan Nieuwenhuizen <janneke@gnu.org>

(define (interface-doc-string interface grob-description)
  (let* ((name (car interface))
	 (desc (cadr interface))
	 (props (sort (caddr interface) symbol<?))
	 (docfunc (lambda (pr)
		    (property->texi
		     'backend pr grob-description)))
	 (iprops (filter (lambda (x) (object-property x 'backend-internal))
			 props))
	 (uprops (filter
		  (lambda (x) (not (object-property x 'backend-internal)))
		  props))
	 (user-propdocs (map docfunc uprops))
	 (internal-propdocs (map docfunc iprops)))

    (string-append
     desc

     (if (pair? uprops)
	 (string-append
	  "\n\n@unnumberedsubsubsec User settable properties:\n"
	  (description-list->texi user-propdocs))
	 "")

     (if (pair? iprops)
	 (string-append
	  "\n\n@unnumberedsubsubsec Internal properties: \n"
	  (description-list->texi internal-propdocs))
	 ""))))

(define iface->grob-table (make-vector 61 '()))
;; extract ifaces, and put grob into the hash table.
(map
 (lambda (x)
   (let* ((metah (assoc 'meta (cdr x)))
	  (meta (cdr metah))
	  (ifaces (cdr (assoc 'interfaces meta))))

     (map (lambda (iface)
	    (hashq-set!
	     iface->grob-table iface
	     (cons (car x)
		   (hashq-ref iface->grob-table iface '()))))
	  ifaces)))
 all-grob-descriptions)

;; First level Interface description
(define (interface-doc interface)
  (let ((name (symbol->string (car interface))))
    (make <texi-node>
      #:name name
      #:text (string-append
	      (interface-doc-string (cdr interface) '())
	      "\n\n"
	      "This grob interface is used in the following graphical objects: "

	      (human-listify
	       (map ref-ify
		    (sort 
		     (map symbol->string
			  (hashq-ref iface->grob-table (car interface) '()))
		     string<?)))))))

(define (grob-alist->texi alist)
  (let* ((uprops (filter (lambda (x) (not (object-property x 'backend-internal)))
			 (map car alist))))

    (description-list->texi
     (map (lambda (y) (property->texi 'backend y alist))
	  uprops))))

(define (grob-doc description)
  "Given a property alist DESCRIPTION, make a documentation
node."

  (let* ((metah (assoc 'meta description))
	 (meta (cdr metah))
	 (name (cdr (assoc 'name meta)))
	 ;;       (bla (display name))
	 (ifaces (map lookup-interface (cdr (assoc 'interfaces meta))))
	 (ifacedoc (map (lambda (iface)
			  (if (pair? iface)
			      (ref-ify (symbol->string (car iface)))
			      (ly:error (_ "pair expected in doc ~s") name)))
			(reverse ifaces)))
	 (engravers (filter
		     (lambda (x) (engraver-makes-grob? name x)) all-engravers-list))
	 (namestr (symbol->string name))
	 (engraver-names (map symbol->string (map ly:translator-name engravers))))

    (make <texi-node>
      #:name namestr
      #:text
      (string-append
       namestr " objects are created by: "
       (human-listify (map ref-ify
			   (map engraver-name engraver-names)))
       "\n\nStandard settings: \n\n"
       (grob-alist->texi description)
       "\n\nThis object supports the following interfaces: \n"
       (human-listify ifacedoc)))))

(define (all-grobs-doc)
  (make <texi-node>
    #:name "All layout objects"
    #:desc "Description and defaults for all Grobs"
    #:children
    (map (lambda (x) (grob-doc (cdr x)))  all-grob-descriptions)))

(define interface-description-alist
  (hash-fold
   (lambda (key val prior)
     (cons (cons key val)  prior))
   '() (ly:all-grob-interfaces)))

(set! interface-description-alist (sort interface-description-alist alist<?))

;;;;;;;;;; check for dangling backend properties.
(define (mark-interface-properties entry)
  (map (lambda (x) (set-object-property! x 'iface-marked #t))
       (caddr (cdr entry))))

(map mark-interface-properties interface-description-alist)

(define (check-dangling-properties prop)
  (if (not (object-property prop 'iface-marked))
      (ly:error (string-append "define-grob-properties.scm: "
		(_ "can't find interface for property: ~S")) prop)))

(map check-dangling-properties all-backend-properties)

;;;;;;;;;;;;;;;;

(define (lookup-interface name)
  (let* ((entry (hashq-ref (ly:all-grob-interfaces) name #f)))
    (if entry
	entry
	(ly:error (_ "unknown Grob interface: ~S") name))))

(define (all-interfaces-doc)
  (make <texi-node>
    #:name "Graphical Object Interfaces"
    #:desc "Building blocks of graphical objects"
    #:children
    (map interface-doc interface-description-alist)))

(define (backend-properties-doc-string lst)
  (let* ((ps (sort (map symbol->string lst) string<?))
	 (descs (map (lambda (prop)
		       (property->texi 'backend (string->symbol prop) '())) ps))
	 (texi (description-list->texi descs)))
    texi))

;;(dump-node (grob-doc (cdadr all-grob-descriptions)) (current-output-port) 0 )
(define (backend-doc-node)
  (make <texi-node>
    #:name "Backend"
    #:desc "Reference for the layout engine"
    #:children
    (list
     (all-grobs-doc)
     (all-interfaces-doc)
     (make <texi-node>
       #:name "User backend properties"
       #:desc "All tunable properties in a big list"
       #:text (backend-properties-doc-string all-user-grob-properties))
     (make <texi-node>
       #:name "Internal backend properties"
       #:desc "All internal layout properties in a big list"
       #:text (backend-properties-doc-string all-internal-grob-properties)))))
