(defpackage :fancy-listener

   (:use :cl )
   (:export :row :column :button :stream-disp :fancy-listener *interface-layout*))

 
 (defpackage :fl-user

   (:use :cl :fancy-listener))

 (in-package :fl-user)
 (declaim (special fancy-listener:*interface-layout*))

 
 (defmacro with-pp ((pane) &body body)
   `(capi:apply-in-pane-process ,pane
                                (lambda ()
                                  ,@body)))
 
 (defun push-widget (widget)
   (when *interface-layout*
     (with-pp (*interface-layout*)
       (when (capi:layout-description *interface-layout*)
         (push :divider (capi:layout-description *interface-layout*)))
       (push widget (capi:layout-description *interface-layout*)))))
 
 (defun pop-widget ()
   (when *interface-layout*
     (with-pp (*interface-layout*)

       (pop (capi:layout-description *interface-layout*))
       (when (eql (first (capi:layout-description *interface-layout*))
                  :divider)
         (pop (capi:layout-description *interface-layout*))))))

 
 (in-package :fancy-listener)

 (defvar *interface-layout* nil)

 
 (defun row (&rest components)
   (make-instance 'capi:row-layout :children components))
 
 (defun column (&rest components)
   (make-instance 'capi:column-layout :children components))
 
 (defun button (cb &optional (text "Go!"))
   (make-instance 'capi:push-button
                  :text text
                  :callback cb))
 
 (defun stream-disp ()
   (let ((out-pane (make-instance 'capi:collector-pane)))
     (values out-pane
             (capi:collector-pane-stream out-pane))))
  
 (defun listener-pane ()
   (make-instance 'capi:listener-pane))
 
 
 (defun interface ()
   (setf *interface-layout* (column))
   (let* ((listener-pane (listener-pane))
          (result (make-instance 'capi:interface
                                 :layout (row listener-pane
                                              :divider
                                              *interface-layout*))))
     (capi:interactive-pane-execute-command listener-pane "(in-package :fl-user)")
     result))

 
 (defun fancy-listener ()
   (capi:display (interface)))