;; 
;; qwiki-menu - extension for qwiki to display a menu on all pages
;;
;; The menu is itself a wiki file so it can be easily maintained.
;; 
;; Copyright (c) 2009-2012 Peter Bex
;;
;;  Redistribution and use in source and binary forms, with or without
;;  modification, are permitted provided that the following conditions
;;  are met:
;; 
;;  - Redistributions of source code must retain the above copyright
;;  notice, this list of conditions and the following disclaimer.
;; 
;;  - Redistributions in binary form must reproduce the above
;;  copyright notice, this list of conditions and the following
;;  disclaimer in the documentation and/or other materials provided
;;  with the distribution.
;; 
;;  - Neither name of the copyright holders nor the names of its
;;  contributors may be used to endorse or promote products derived
;;  from this software without specific prior written permission.
;; 
;;  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND THE
;;  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
;;  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
;;  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
;;  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR THE
;;  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
;;  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
;;  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
;;  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
;;  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
;;  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
;;  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
;;  POSSIBILITY OF SUCH DAMAGE.

(module qwiki-menu
	(menu-install! menu-file)

(import chicken scheme)
(use data-structures files svnwiki-sxml qwiki qwiki-sxml sxml-transforms)

(define menu-file (make-parameter "/menu"))

(define menu-rules
  `((wiki-page
     ((body
       *preorder*
       . ,(lambda (tag contents)
            (if (file-exists? (make-pathname (qwiki-source-path) (menu-file)))
                `(body (div (@ (id "menu"))
                            ,(call-with-input-file
                                 (make-pathname (qwiki-source-path) (menu-file))
                               svnwiki->sxml))
                       . ,contents)
                `(body . ,contents)))))
     . ,(lambda contents contents))
    ,@alist-conv-rules*))

(define (update-menu! path page)
  (when (and (menu-file) (equal? path (string-split (menu-file) "/")))
    (qwiki-clear-cache!)))

(define (delete-menu! path)
  (when (and (menu-file) (equal? path (string-split (menu-file) "/")))
    (qwiki-clear-cache!)))

(define (menu-install!)
  (qwiki-extensions (cons menu-rules (qwiki-extensions)))
  (qwiki-update-handlers (cons update-menu! (qwiki-update-handlers)))
  (qwiki-delete-handlers (cons delete-menu! (qwiki-delete-handlers))))
)