fix for #39584. user should be asked to remove non existing newsgroups, like in 4.x

r/sr=bienvenu

mailnews/news/public/nsINntpIncomingServer.idl

@@ -112,7 +112,7 @@ interface nsINntpIncomingServer : nsISupports {
 	readonly attribute string firstGroupNeedingExtraInfo;
     void setGroupNeedsExtraInfo(in string name, in boolean needsExtraInfo);
 
-	void groupNotFound(in string group, in boolean opening);
+	void groupNotFound(in nsIMsgWindow window, in string group, in boolean opening);
 
 	void setPrettyNameForGroup(in string name, in string prettyName);
 };

mailnews/news/resources/locale/en-US/news.properties

@@ -49,8 +49,7 @@ downloadingArticlesForOffline=Downloading articles %S-%S in %S
 onlyCancelOneMessage=You can only cancel one article at a time.
 
 # LOCALIZATION NOTE (autoUnsubscribeText): %1$S is the newsgroup and %2$S is the newsgroup-server it is being removed from.
-autoUnsubscribeText=The group %1$S could not be updated, because it could not be found on the server %2$S. The group may no longer exist, or the server may have stopped carrying it.
-autoUnsubscribeButtonText=Unsubscribe
+autoUnsubscribeText=The newsgroup %1$S does not appear to exist on the host %2$S.  Would you like to unsubscribe from it?
 
 # LOCALIZATION NOTE (Error -304): In the following item, don't translate "NNTP"
 # Error - server error

mailnews/news/src/nsNNTPProtocol.cpp

@@ -2161,7 +2161,7 @@ PRInt32 nsNNTPProtocol::SendFirstNNTPCommandResponse()
             PR_LOG(NNTP,PR_LOG_ALWAYS,("(%p) group (%s) not found, so unset m_currentGroup",this,(const char *)group_name));
             m_currentGroup = "";
 
-            m_nntpServer->GroupNotFound((const char *)group_name, PR_TRUE /* opening */);
+            m_nntpServer->GroupNotFound(m_msgWindow, group_name.get(), PR_TRUE /* opening */);
         }
 
         /* if the server returned a 400 error then it is an expected
@@ -2522,6 +2522,8 @@ nsresult nsNNTPProtocol::MarkCurrentMsgRead()
       msgHdr->GetIsRead(&isRead);
       if (!isRead)
         msgHdr->MarkRead(PR_TRUE);
+
+      printf("do work here\n");
     }
   }
   return rv;
@@ -4088,7 +4090,7 @@ PRInt32 nsNNTPProtocol::DisplayNewsRCResponse()
           rv = m_newsFolder->GetAsciiName(getter_Copies(name));
 
           if (NS_SUCCEEDED(rv)) {
-            m_nntpServer->GroupNotFound((const char *)name, PR_FALSE);
+            m_nntpServer->GroupNotFound(m_msgWindow, name.get(), PR_FALSE);
           }
 
           PR_LOG(NNTP,PR_LOG_ALWAYS,("(%p) NO_GROUP, so unset m_currentGroup", this));

mailnews/news/src/nsNntpIncomingServer.cpp

@@ -54,6 +54,9 @@
 #include "nsAppDirectoryServiceDefs.h"
 #include "nsInt64.h"
 #include "nsMsgUtils.h"
+#include "nsIPrompt.h"
+#include "nsIStringBundle.h"
+#include "nntpCore.h"
 
 #define INVALID_VERSION         0
 #define VALID_VERSION           1
@@ -1562,11 +1565,52 @@ nsNntpIncomingServer::SetGroupNeedsExtraInfo(const char *name, PRBool needsExtra
 
 
 NS_IMETHODIMP
-nsNntpIncomingServer::GroupNotFound(const char *name, PRBool opening)
+nsNntpIncomingServer::GroupNotFound(nsIMsgWindow *aMsgWindow, const char *aName, PRBool aOpening)
 {
-  NS_ENSURE_ARG_POINTER(name);
-  printf("alert, asking if the user wants to auto unsubscribe from %s\n", name);
-  return NS_OK;
+  NS_ENSURE_ARG_POINTER(aName);
+  NS_ENSURE_ARG_POINTER(aMsgWindow);
+
+  nsresult rv;
+
+  nsCOMPtr <nsIPrompt> prompt;
+  rv = aMsgWindow->GetPromptDialog(getter_AddRefs(prompt));
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  nsCOMPtr <nsIStringBundleService> bundleService = do_GetService(NS_STRINGBUNDLE_CONTRACTID,&rv);
+  NS_ENSURE_SUCCESS(rv,rv);
+  
+  nsCOMPtr <nsIStringBundle> bundle;
+  rv = bundleService->CreateBundle(NEWS_MSGS_URL, getter_AddRefs(bundle));
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  nsAutoString groupStr;
+  groupStr.AssignWithConversion(aName);
+
+  nsXPIDLCString hostname;
+  rv = GetHostName(getter_Copies(hostname));
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  nsAutoString hostStr;
+  hostStr.AssignWithConversion(hostname.get());
+
+  const PRUnichar *formatStrings[2] = { groupStr.get(), hostStr.get() };
+  nsXPIDLString confirmText;
+  rv = bundle->FormatStringFromName(
+                    NS_LITERAL_STRING("autoUnsubscribeText").get(),
+                    formatStrings, 2,
+                    getter_Copies(confirmText));
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  PRBool confirmResult = PR_FALSE;
+  rv = prompt->Confirm(nsnull, confirmText, &confirmResult);
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  if (confirmResult) {
+    rv = Unsubscribe(groupStr.get());
+    NS_ENSURE_SUCCESS(rv,rv);
+  }
+  
+  return rv;
 }
 
 NS_IMETHODIMP