oc-mail: Use body.peek to preload message bodies

In this way, we do not modify the flags (\Seen) on preloading.
The IMAP server returns the content without .peek section so
it is removed.

This also performs the modification intended by the following
Pull Request:

https://github.com/Zentyal/sogo/pull/50

That tried to avoid set \Seen flag when preloading message bodies
on synchronisation. But in this case we are not incrementing the
modseq as we are not modifying any messages flags.

NEWS

@@ -2,6 +2,7 @@ master
 ------
 
 Enhancements
+ - Improve sync speed from Outlook by non-reprocessing already downloaded unread mails
  - Give support to calendar sharing invitations
  - Missing contact fields are now saved and available when sharing it
     (Office, Profession, Manager's name, Assistant's name, Spouse/Partner, Anniversary)

OpenChange/MAPIStoreMailFolder.m

@@ -1500,6 +1500,15 @@ _parseCOPYUID (NSString *line, NSArray **destUIDsP)
                     {
                       [bodyPartKeys addObject: bodyPartKey];
                       messageUid = [self messageUIDFromMessageKey: messageKey];
+                      /* If the bodyPartKey include peek, remove it as it is not returned
+                         as key in the IMAP server response.
+
+                         IMAP conversation example:
+                         a4 UID FETCH 1 (UID BODY.PEEK[text])
+                         * 1 FETCH (UID 1 BODY[TEXT] {1677}
+                      */
+                      bodyPartKey = [bodyPartKey stringByReplacingOccurrencesOfString: @"body.peek"
+                                                                           withString: @"body"];
                       [keyAssoc setObject: bodyPartKey forKey: messageUid];
                     }
                 }

OpenChange/MAPIStoreMailMessage.m

@@ -1627,11 +1627,7 @@ _compareBodyKeysByPriority (id entry1, id entry2, void *data)
   if (!headerSetup)
     [self _fetchHeaderData];
 
-  if ([mimeKey hasPrefix: @"body.peek"])
-    bodyPartKey = [NSString stringWithFormat: @"body[%@]",
-                          [mimeKey _strippedBodyKey]];
-  else
-    bodyPartKey = mimeKey;
+  bodyPartKey = mimeKey;
 
   return bodyPartKey;
 }