From 52612dddb47e3027e465841eb5b9b2e7b73f921d Mon Sep 17 00:00:00 2001
From: mguessan <mguessan@3d1905a2-6b24-0410-a738-b14d5a86fcbd>
Date: Thu, 22 Apr 2010 21:50:16 +0000
Subject: [PATCH] IMAP: poll folder every 30 seconds in IDLE mode, clear cached
 message

git-svn-id: http://svn.code.sf.net/p/davmail/code/trunk@1014 3d1905a2-6b24-0410-a738-b14d5a86fcbd
---
 .../davmail/exchange/ExchangeSession.java     | 26 +++++++++--
 src/java/davmail/imap/ImapConnection.java     | 43 +++++++++++--------
 2 files changed, 48 insertions(+), 21 deletions(-)

diff --git a/src/java/davmail/exchange/ExchangeSession.java b/src/java/davmail/exchange/ExchangeSession.java
index 0d4104ac..30c478af 100644
--- a/src/java/davmail/exchange/ExchangeSession.java
+++ b/src/java/davmail/exchange/ExchangeSession.java
@@ -1457,10 +1457,22 @@ public class ExchangeSession {
         }
 
         /**
-         * Calendar folder flag.
-         *
-         * @return true if this is a calendar folder
+         * Get current folder messages imap uids
+         * @return imap uid list
          */
+        public List<Long> getImapUidList() {
+            ArrayList<Long> imapUidList = new ArrayList<Long>();
+            for (ExchangeSession.Message message : messages) {
+                imapUidList.add(message.getImapUid());
+            }
+            return imapUidList;
+        }
+
+            /**
+            * Calendar folder flag.
+            *
+            * @return true if this is a calendar folder
+            */
         public boolean isCalendar() {
             return "urn:content-classes:calendarfolder".equals(contentClass);
         }
@@ -1473,6 +1485,14 @@ public class ExchangeSession {
         public boolean isContact() {
             return "urn:content-classes:contactfolder".equals(contentClass);
         }
+
+        /**
+         * drop cached message
+         */
+        public void clearCache() {
+            messages.cachedMimeMessage = null;
+            messages.cachedMessageImapUid = 0;
+        }
     }
 
     /**
diff --git a/src/java/davmail/imap/ImapConnection.java b/src/java/davmail/imap/ImapConnection.java
index d7c05df7..cf3cc03c 100644
--- a/src/java/davmail/imap/ImapConnection.java
+++ b/src/java/davmail/imap/ImapConnection.java
@@ -40,6 +40,7 @@ import java.net.SocketTimeoutException;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.*;
+import java.util.logging.Logger;
 
 /**
  * Dav Gateway smtp connection implementation.
@@ -418,13 +419,20 @@ public class ImapConnection extends AbstractConnection {
                                     sendClient(commandId + " OK APPEND completed");
                                 } else if ("idle".equalsIgnoreCase(command)) {
                                     sendClient("+ idling ");
+                                    // clear cache before going to idle mode
+                                    currentFolder.clearCache();
+                                    DavGatewayTray.resetIcon();
+                                    int count = 0;
                                     while (!in.ready()) {
-                                        ExchangeSession.MessageList currentMessages = currentFolder.messages;
-                                        if (session.refreshFolder(currentFolder)) {
-                                            handleRefresh(currentFolder, currentMessages);
+                                        if (++count >= 30) {
+                                            count = 0;
+                                            List<Long> previousImapUidList = currentFolder.getImapUidList();
+                                            if (session.refreshFolder(currentFolder)) {
+                                                handleRefresh(previousImapUidList, currentFolder.getImapUidList());
+                                            }
                                         }
-                                        // sleep 10 seconds
-                                       Thread.sleep(10000);
+                                        // sleep 1 second
+                                       Thread.sleep(1000);
                                     }
                                     // read DONE line
                                     line = readClient();
@@ -436,9 +444,9 @@ public class ImapConnection extends AbstractConnection {
                                 } else if ("noop".equalsIgnoreCase(command) || "check".equalsIgnoreCase(command)) {
                                     if (currentFolder != null) {
                                         DavGatewayTray.debug(new BundleMessage("LOG_IMAP_COMMAND", command, currentFolder.folderName));
-                                        ExchangeSession.MessageList currentMessages = currentFolder.messages;
+                                        List<Long> previousImapUidList = currentFolder.getImapUidList();
                                         if (session.refreshFolder(currentFolder)) {
-                                            handleRefresh(currentFolder, currentMessages);
+                                            handleRefresh(previousImapUidList, currentFolder.getImapUidList());
                                         }
                                     }
                                     sendClient(commandId + " OK " + command + " completed");
@@ -529,18 +537,17 @@ public class ImapConnection extends AbstractConnection {
         DavGatewayTray.resetIcon();
     }
 
-    private void handleRefresh(ExchangeSession.Folder currentFolder, ExchangeSession.MessageList currentMessages) throws IOException {
-        // build new uid set
-        HashSet<Long> uidSet = new HashSet<Long>();
-        for (ExchangeSession.Message message : currentFolder.messages) {
-            uidSet.add(message.getImapUid());
-        }
-        // send expunge untagged response for removed IMAP message uids
-        // note: some STORE commands trigger a uid change in Exchange,
-        // thus those messages are expunged and reappear with a new uid
+    /**
+     * Send expunge untagged response for removed IMAP message uids.
+     * @param previousImapUidList uid list before refresh
+     * @param imapUidList uid list after refresh
+     * @throws IOException on error
+     */
+    private void handleRefresh(List<Long> previousImapUidList, List<Long> imapUidList) throws IOException {
+        //
         int index = 1;
-        for (ExchangeSession.Message message : currentMessages) {
-            if (!uidSet.contains(message.getImapUid())) {
+        for (long previousImapUid : previousImapUidList) {
+            if (!imapUidList.contains(previousImapUid)) {
                 sendClient("* " + index + " EXPUNGE");
             } else {
                 index++;