From fa656577d1968e473c06626a644fafa554e48c66 Mon Sep 17 00:00:00 2001
From: ed <s@ocv.me>
Date: Sun, 21 Feb 2021 21:08:53 +0100
Subject: [PATCH] prevent non-spa navigation while uploading

---
 copyparty/web/browser.js |  8 +++++---
 copyparty/web/up2k.js    | 35 ++++++++++++++++++++++++++---------
 2 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/copyparty/web/browser.js b/copyparty/web/browser.js
index c49e1cea..737978a9 100644
--- a/copyparty/web/browser.js
+++ b/copyparty/web/browser.js
@@ -980,9 +980,11 @@ function apply_perms(perms) {
 	}
 
 	var act = document.querySelector('#ops>a.act');
-	var areq = act.getAttribute('data-perm');
-	if (areq && !has(perms, areq))
-		goto();
+	if (act) {
+		var areq = act.getAttribute('data-perm');
+		if (areq && !has(perms, areq))
+			goto();
+	}
 
 	var have_write = has(perms, "write");
 	var tds = document.querySelectorAll('#u2conf td');
diff --git a/copyparty/web/up2k.js b/copyparty/web/up2k.js
index 13420c4d..2f3f4c96 100644
--- a/copyparty/web/up2k.js
+++ b/copyparty/web/up2k.js
@@ -424,6 +424,7 @@ function up2k_init(have_crypto) {
 
     var tasker = (function () {
         var mutex = false;
+        var was_busy = false;
 
         function taskerd() {
             if (mutex)
@@ -442,16 +443,25 @@ function up2k_init(have_crypto) {
                         st.busy.upload.length;
                 }
 
-                if (flag) {
-                    var need_flag = 0 !=
-                        st.todo.hash.length +
-                        st.todo.handshake.length +
-                        st.todo.upload.length +
-                        st.busy.hash.length +
-                        st.busy.handshake.length +
-                        st.busy.upload.length;
+                var is_busy = 0 !=
+                    st.todo.hash.length +
+                    st.todo.handshake.length +
+                    st.todo.upload.length +
+                    st.busy.hash.length +
+                    st.busy.handshake.length +
+                    st.busy.upload.length;
 
-                    if (need_flag) {
+                if (was_busy != is_busy) {
+                    was_busy = is_busy;
+
+                    if (is_busy)
+                        window.addEventListener("beforeunload", warn_uploader_busy);
+                    else
+                        window.removeEventListener("beforeunload", warn_uploader_busy);
+                }
+
+                if (flag) {
+                    if (is_busy) {
                         var now = new Date().getTime();
                         flag.take(now);
                         if (!flag.ours) {
@@ -1108,5 +1118,12 @@ function up2k_init(have_crypto) {
 }
 
 
+function warn_uploader_busy(e) {
+    e.preventDefault();
+    e.returnValue = '';
+    return "upload in progress, click abort and use the file-tree to navigate instead";
+}
+
+
 if (document.querySelector('#op_up2k.act'))
     goto_up2k();