1 files changed, 76 insertions, 37 deletions

diff --git a/pdf-over-gui/src/main/java/at/asit/pdfover/gui/utils/UpdateCheckManager.java b/pdf-over-gui/src/main/java/at/asit/pdfover/gui/utils/UpdateCheckManager.java
index d6e650ba..92104176 100644
--- a/pdf-over-gui/src/main/java/at/asit/pdfover/gui/utils/UpdateCheckManager.java
+++ b/pdf-over-gui/src/main/java/at/asit/pdfover/gui/utils/UpdateCheckManager.java
@@ -2,6 +2,8 @@ package at.asit.pdfover.gui.utils;
 
 import java.awt.Desktop;
 import java.net.URI;
+import java.util.ArrayList;
+import java.util.function.Consumer;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -24,6 +26,72 @@ public final class UpdateCheckManager {
     private static Thread updateCheckThread = null;
     private static boolean needsCheck = false;
 
+    public enum Status { NOT_CHECKED, CHECKING, OUTDATED, UP_TO_DATE, FAILED };
+    private static Status currentStatus = Status.NOT_CHECKED;
+    public static Status getCurrentStatus() {
+        synchronized (UpdateCheckManager.class) {
+            return currentStatus;
+        }
+    }
+
+    private static ArrayList<Consumer<Status>> statusCallbacks = new ArrayList<>();
+    public static void registerStatusCallback(Consumer<Status> f) {
+        synchronized (UpdateCheckManager.class) {
+            statusCallbacks.add(f);
+            f.accept(currentStatus);
+        }
+    }
+
+    private static void setStatus(Status status) {
+        synchronized(UpdateCheckManager.class) {
+            currentStatus = status;
+            for (Consumer<Status> f : statusCallbacks)
+                f.accept(status);
+        }
+    }
+
+    private static String latestVersionNotified = null;
+    private static Status runCheck(Shell shell) {
+        HttpClient client = (HttpClient) BKUHelper.getHttpClient();
+        GetMethod method = new GetMethod(Constants.CURRENT_RELEASE_URL);
+        try {
+            client.executeMethod(method);
+            final String version = method.getResponseBodyAsString().trim();
+            if (!VersionComparator.before(Constants.APP_VERSION, version))
+                return Status.UP_TO_DATE;
+
+            if ((latestVersionNotified == null) || VersionComparator.before(latestVersionNotified, version)) {
+                latestVersionNotified = version;
+                // invoke GUI message in main thread
+                shell.getDisplay().asyncExec(() -> {
+                    Dialog info = new Dialog(shell,
+                            Messages.getString("version_check.UpdateTitle"),
+                            String.format(Messages.getString("version_check.UpdateText"), version),
+                            BUTTONS.OK_CANCEL, ICON.INFORMATION);
+
+                    if (info.open() == SWT.OK)
+                    {
+                        if (Desktop.isDesktopSupported()) {
+                            try {
+                                Desktop.getDesktop().browse(new URI(Constants.UPDATE_URL));
+                            } catch (Exception e) {
+                                log.error("Error opening update location ", e);
+                            }
+                        } else {
+                            log.info("SWT Desktop is not supported on this platform");
+                            Program.launch(Constants.UPDATE_URL);
+                        }
+                    }
+                });
+            }
+
+            return Status.OUTDATED;
+        } catch (Exception e) {
+            log.error("Error downloading update information: ", e);
+            return Status.FAILED;
+        }
+    }
+
     public static void checkNow(Shell shell) {
         if (Constants.APP_VERSION == null)
             return;
@@ -34,48 +102,19 @@ public final class UpdateCheckManager {
 
             needsCheck = true;
             updateCheckThread = new Thread(() -> {
+                synchronized(UpdateCheckManager.class) {
+                    setStatus(Status.CHECKING);
+                }
                 while (true) {
+                    Status status = runCheck(shell);
                     synchronized (UpdateCheckManager.class) {
-                        if (!needsCheck) {
+                        if (!UpdateCheckManager.needsCheck) {
+                            setStatus(status);
                             UpdateCheckManager.updateCheckThread = null;
                             return;
                         }
-                        needsCheck = false;
-                    }
-                    HttpClient client = (HttpClient) BKUHelper.getHttpClient();
-                    GetMethod method = new GetMethod(Constants.CURRENT_RELEASE_URL);
-                    try {
-                        client.executeMethod(method);
-                        final String version = method.getResponseBodyAsString().trim();
-                        if (!VersionComparator.before(Constants.APP_VERSION, version))
-                            return;
-
-                        // wait 500ms before invoke the GUI message, because GUI had to be started from
-                        // main thread
-                        try { Thread.sleep(500); } catch (InterruptedException e1) { }
-                        // invoke GUI message in main thread
-                        shell.getDisplay().asyncExec(() -> {
-                            Dialog info = new Dialog(shell,
-                                    Messages.getString("version_check.UpdateTitle"),
-                                    String.format(Messages.getString("version_check.UpdateText"), version),
-                                    BUTTONS.OK_CANCEL, ICON.INFORMATION);
-
-                            if (info.open() == SWT.OK)
-                            {
-                                if (Desktop.isDesktopSupported()) {
-                                    try {
-                                        Desktop.getDesktop().browse(new URI(Constants.UPDATE_URL));
-                                    } catch (Exception e) {
-                                        log.error("Error opening update location ", e);
-                                    }
-                                } else {
-                                    log.info("SWT Desktop is not supported on this platform");
-                                    Program.launch(Constants.UPDATE_URL);
-                                }
-                            }
-                        });
-                    } catch (Exception e) {
-                        log.error("Error downloading update information: ", e);
+                        UpdateCheckManager.needsCheck = false;
+                        setStatus(Status.CHECKING);
                     }
                 }
             });