Added progress messages and quick access to exported files (#1112)

app/MindWork AI Studio/Tools/FileExportNotifications.cs

@@ -0,0 +1,43 @@
+namespace AIStudio.Tools;
+
+/// <summary>
+/// Shows the notifications of file exports in one window, and keeps a late notification that an export
+/// runs from appearing after its end.
+/// </summary>
+/// <remarks>
+/// FileExportFeedback sends its notifications in the right order, but they may take effect in another
+/// one. The notification that an export runs comes late, from a timer, and waits in the queue of the
+/// renderer. The end of an export usually comes from a component, on the thread of the renderer, and
+/// takes effect right away: it overtakes the waiting notification, which would then appear after the
+/// end and stay until the user closes it. So we remember which exports ended and drop what comes late.
+/// <br/><br/>
+/// One key stays per export which ended, for as long as the window lives. That is a few bytes per
+/// file the user saved, which is not worth a cleanup that could drop a key too early.
+/// </remarks>
+/// <param name="snackbar">The notifications of the window.</param>
+public sealed class FileExportNotifications(ISnackbar snackbar)
+{
+    private readonly HashSet<string> finishedExports = [];
+
+    public void ShowRunning(DataFileExportRunningMessage message)
+    {
+        if (this.finishedExports.Contains(message.Key))
+            return;
+
+        message.Show(snackbar);
+    }
+
+    /// <param name="message">The notification of the success.</param>
+    /// <param name="closesAutomatically">Whether the notification closes after a few seconds, as the user chose.</param>
+    public void ShowSuccess(DataFileExportSuccessMessage message, bool closesAutomatically)
+    {
+        this.finishedExports.Add(message.Key);
+        message.Show(snackbar, closesAutomatically);
+    }
+
+    public void HideRunning(DataFileExportRunningMessage message)
+    {
+        this.finishedExports.Add(message.Key);
+        message.Hide(snackbar);
+    }
+}