From 74613c4d907c485040691ef4f863a92effa09080 Mon Sep 17 00:00:00 2001
From: "Pasha.K" <pasha@inasan.ru>
Date: Wed, 14 Jul 2021 23:06:15 +0300
Subject: [PATCH] register-hash-cb function added, version bump

---
 README.md  | 14 ++++++++++++++
 omg.asd    |  2 +-
 omgui.lisp | 17 +++++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 70fcbe3..44c8a03 100644
--- a/README.md
+++ b/README.md
@@ -84,6 +84,20 @@ But many of useful JS and DOM-manipulating functions are provided by `omgui` pac
 
 - `(load-js-script url)` - load JS script from `url`.
 
+- `(register-hash-cb hash cb)` - register a callback to call when URL hash part changes. With this function you can, for example, automatically mark session as debug one, when you open URL like `http://localhost:7500/#debug`:
+
+  ```
+  (defun-r debug-me ()
+    (set-debug-session (current-session-id)))
+
+  (defun-r my-boot ()
+    (register-hash-cb "#debug" (lambda () (debug-me))))
+
+  (add-to-boot '(my-boot))
+  ```
+
+  If the page is loaded with the registered hash part, the callback will be executed immediately during `register-hash-cb` call.
+
 ### Modal dialogs
 
 You can display modal dialog in the browser using the `modal-dialog` macro:
diff --git a/omg.asd b/omg.asd
index c75e379..00db830 100644
--- a/omg.asd
+++ b/omg.asd
@@ -1,6 +1,6 @@
 (defsystem "omg"
   :description "A Common Lisp library to build fully dynamic web interfaces"
-  :version "0.1.1"
+  :version "0.1.2"
   :author "Pavel Kaygorodov <hemml@me.com>"
   :licence "GPLv3"
   :depends-on ("clack" "websocket-driver-server" "bordeaux-threads" "trivial-utf-8")
diff --git a/omgui.lisp b/omgui.lisp
index 9ddae3f..faba9f0 100644
--- a/omgui.lisp
+++ b/omgui.lisp
@@ -31,6 +31,7 @@
            page-height
            parent-element
            prevent-page-close
+           register-hash-cb
            remove-element
            visible-width
            visible-height
@@ -515,3 +516,19 @@
           (load-js-script "https://www.youtube.com/iframe_api"))
         (make-player))))
   nil)
+
+
+(defparameter-f *hash-change-cbs* nil)
+
+(defun-f register-hash-cb (hsh cb)
+  (labels ((mcb (&optional ev)
+             (let* ((hs (jscl::oget (jscl::%js-vref "location") "hash"))
+                    (cb (assoc hs *hash-change-cbs* :test #'equal)))
+               (jslog hs)
+               (if cb (funcall (cdr cb))))))
+    (if (not *hash-change-cbs*)
+        (setf (jscl::oget (jscl::%js-vref "window") "onhashchange")
+              #'mcb))
+    (push (cons hsh cb) *hash-change-cbs*)
+    (mcb))
+  nil)