Further re-work of document saving in the iOS app

Now, finally, I think it works as it should, knock on wood. After an
auto-save (or explicit save by tapping the button), the edited
document does show up with its auto-saved contents if you open it from
iCloud Drive or Nextcloud while it is still open in the iOS app.

What I was missing was that the document hadn't actually been saved by
the core (to the temporary copy) until we get the
LOK_CALLBACK_UNO_COMMAND_RESULT for the .uno:Save. We must call the
-[UIDocumentsaveToURL:forSaveOperation:completionHandler:] only upon
receiving that callback.

Change-Id: I10486f3bc587c871ee2644a0c097493f33baf420
Reviewed-on: https://gerrit.libreoffice.org/c/online/+/91880
Tested-by: Jenkins CollaboraOffice <jenkinscollaboraoffice@gmail.com>
Reviewed-by: Tor Lillqvist <tml@collabora.com>

kit/ChildSession.cpp

@@ -32,6 +32,10 @@
 #include <Poco/Net/AcceptCertificateHandler.h>
 #endif
 
+#ifdef IOS
+#import "DocumentViewController.h"
+#endif
+
 #include <common/FileUtil.hpp>
 #include <common/JsonUtil.hpp>
 #include <common/Authorization.hpp>
@@ -2475,6 +2479,31 @@ void ChildSession::loKitCallback(const int type, const std::string& payload)
         break;
     case LOK_CALLBACK_UNO_COMMAND_RESULT:
         sendTextFrame("unocommandresult: " + payload);
+#ifdef IOS
+        {
+            // After the document has been saved (into the temporary copy that we set up in
+            // -[CODocument loadFromContents:ofType:error:]), save it also using the system API so
+            // that file provider extensions notice.
+
+            Parser parser;
+            Poco::Dynamic::Var var = parser.parse(payload);
+            Object::Ptr object = var.extract<Object::Ptr>();
+
+            auto commandName = object->get("commandName");
+            auto success = object->get("success");
+
+            if (!commandName.isEmpty() && commandName.toString() == ".uno:Save" && !success.isEmpty() && success.toString() == "true")
+            {
+                CODocument *document = [[DocumentViewController singleton] document];
+
+                [document saveToURL:[document fileURL]
+                 forSaveOperation:UIDocumentSaveForOverwriting
+                 completionHandler:^(BOOL success) {
+                        LOG_TRC("ChildSession::loKitCallback() save completion handler gets " << (success?"YES":"NO"));
+                    }];
+            }
+        }
+#endif
         break;
     case LOK_CALLBACK_ERROR:
         {

wsd/DocumentBroker.cpp

@@ -39,10 +39,6 @@
 #include <common/Unit.hpp>
 #include <common/FileUtil.hpp>
 
-#ifdef IOS
-#import "DocumentViewController.h"
-#endif
-
 #include <sys/types.h>
 #include <sys/wait.h>
 
@@ -1288,17 +1284,6 @@ bool DocumentBroker::sendUnoSave(const std::string& sessionId, bool dontTerminat
         const auto command = "uno .uno:Save " + saveArgs;
         forwardToChild(sessionId, command);
         _lastSaveRequestTime = std::chrono::steady_clock::now();
-#ifdef IOS
-        // We need to do this here, also for auto-save, so that file provider extensions notice.
-
-        CODocument *document = [[DocumentViewController singleton] document];
-
-        [document saveToURL:[[[DocumentViewController singleton] document] fileURL]
-           forSaveOperation:UIDocumentSaveForOverwriting
-          completionHandler:^(BOOL success) {
-                LOG_TRC("DocumentBroker::sendUnoSave() save completion handler gets " << (success?"YES":"NO"));
-            }];
-#endif
         return true;
     }