;;;-*- Mode: Lisp; Package: HTTP-DEMO -*-

(in-package :http-user)

;
; Events - Bulletin board examples using events
;

(defparameter *board* nil)

; Form example with input focus

(defun display-bulletin-board (url stream)
  "Form function to display a bulletin board with a text field."
  (let ((title "Feedback"))
    (with-event-handlers
        (make-focus (:java-script :load "document.myform.text.focus()"))
      (with-successful-response (stream :html)
        (with-html-document (:stream stream)
          (with-document-preamble (:stream stream)
            (declare-title title :stream ,stream))
          (with-document-body (:stream stream :events make-focus)
            (with-section-heading (title :stream stream)
              (dolist (topic (reverse *board*))
                (when topic
                  (with-paragraph (:stream stream) 
                    (write-string-quoting-specials topic stream)))
              (with-fillout-form (:post url :name "myform" :stream stream)
                (accept-input 'string "text" :stream stream)
                (accept-input 'submit-button "Submit" :stream stream))))))))))

(defun update-bulletin-board (url stream alist)
  "Response function to add an entry to the bulleting board."
  (bind-query-values (text) (url alist)
    (atomic-push text *board*)
      (display-bulletin-board url stream)))
    
(export-url "http://localhost:8000/board.html"
            :html-computed-form
            :form-function 'display-bulletin-board
            :response-function 'update-bulletin-board)

; Form example with field validation

(defun display-bulletin-board (url stream)
  "Routine to display a bulletin board and a form."
  (let ((title "Feedback"))
    (with-event-handlers
        (make-focus 
         (:java-script :load
          (lambda (stream)
            (fast-format stream "\"document.myform.mysubmit.disabled = true\""))))
      (with-event-handlers
          (check-field 
           (:java-script :key-press 
            (lambda (stream)
              (fast-format stream "\"if (this.value == '') document.myform.mysubmit.disabled = false\""))))
        (with-successful-response (stream :html)
          (with-html-document (:stream stream)
            (with-document-preamble (:stream stream)
              (declare-title title :stream stream))
            (with-document-body (:stream stream :events make-focus)
              (with-section-heading (title :stream stream)
                (dolist (topic (reverse *board*))
                  (with-paragraph (:stream stream) (write-string-quoting-specials topic stream)))
                (with-fillout-form (:post url :name "myform" :stream stream)
                  (accept-input 'string "text" :events check-field :stream stream)
                  (accept-input 'submit-button "mysubmit" :stream stream))))))))))