sunet/scheme/httpd/surflets/surflet-sxml.scm

80 lines
2.0 KiB
Scheme

(define url-rule
`(url *preorder*
. ,(lambda (tag uri . maybe-text)
(surflet-sxml->low-level-sxml
`(a (@ (href ,uri))
,(if (null? maybe-text)
uri
maybe-text))))))
(define plain-html-rule
`(plain-html
*preorder*
. ,(lambda (tag . text) text)))
(define nbsp-rule
`(nbsp . ,(lambda (_) " ")))
(define comment-rule
`(*COMMENT* *preorder*
. ,(lambda (tag . elems)
`("<!-- "
,@elems
"-->"))))
(define default-rules
`(,attribute-rule
,default-rule
,text-rule
,comment-rule
,url-rule
,plain-html-rule
,nbsp-rule))
(define surflet-form-rule
`(surflet-form
;; Must do something to prevent the k-url string to be HTML
;; escaped.
*preorder*
. ,(lambda (trigger k-url . args)
(receive (parameters elems)
(typed-optionals (list symbol? sxml-attribute?) args)
(make-surflet-form k-url ; k-url
(car parameters) ; POST, GET or #f=GET
(cadr parameters); attributes
elems)))))
(define (make-surflet-form k-url method attributes elems)
(let ((real-method (case method
((get GET) "GET")
((post POST) "POST")
((#f) "GET")
(else
(error "invalid method type" method)))))
(surflet-sxml->low-level-sxml
`(form (@ ((method ,real-method)
(action ,k-url)
,@(if attributes (cdr attributes) '())))
,@elems))))
(define input-field-rule
`(,*input-field-trigger*
*preorder*
. ,(lambda (trigger input-field)
(surflet-sxml->low-level-sxml
;; We need a real input-field for input-field-html-tree.
(input-field-html-tree (list trigger input-field))))))
(define surflet-sxml-rules
`(,@default-rules
;; form contents:
,input-field-rule
,surflet-form-rule))
;; Low-Level-SXML is a list that can be understood by
;; display-low-level-sxml. In contains only characters, strings, and
;; thunks.
(define (surflet-sxml->low-level-sxml sxml-tree)
(pre-post-order sxml-tree surflet-sxml-rules))