From ebb2adb52698a082aeb4d6f89feea23765f469bf Mon Sep 17 00:00:00 2001
From: Ambroise Decouttere <ambroise.decouttere@infomaniak.com>
Date: Fri, 9 Jun 2023 14:49:24 +0200
Subject: [PATCH] fix: Reset folder history when it is emptied

---
 MailCore/Cache/MailboxManager.swift | 48 ++++++++++++++---------------
 MailCore/Models/Folder.swift        |  5 +++
 2 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/MailCore/Cache/MailboxManager.swift b/MailCore/Cache/MailboxManager.swift
index fcd89a0b9..4d0287bbc 100644
--- a/MailCore/Cache/MailboxManager.swift
+++ b/MailCore/Cache/MailboxManager.swift
@@ -685,21 +685,8 @@ public class MailboxManager: ObservableObject {
             MailboxInfosManager.instance.updateUnseen(unseenMessages: folder.unreadCount, for: mailbox)
         }
 
-        var remainingOldMessagesToFetch = folder.remainingOldMessagesToFetch
-        while remainingOldMessagesToFetch > 0 {
+        while try await fetchOnePage(folder: folder, direction: .previous) {
             guard !Task.isCancelled else { return }
-
-            if try !(await fetchOnePage(folder: folder, direction: .previous)) {
-                break
-            }
-
-            remainingOldMessagesToFetch -= Constants.pageSize
-            await backgroundRealm.execute { realm in
-                let folder = folder.fresh(using: realm)
-                try? realm.safeWrite {
-                    folder?.remainingOldMessagesToFetch = remainingOldMessagesToFetch
-                }
-            }
         }
     }
 
@@ -730,23 +717,36 @@ public class MailboxManager: ObservableObject {
 
         try await handleMessagesUids(messageUids: messagesUids, folder: folder)
 
-        guard paginationInfo != nil else {
-            return messagesUids.addedShortUids.count > Constants.pageSize
-        }
-
-        if messagesUids.addedShortUids.count < Constants.pageSize || messagesUids.addedShortUids.contains("1") {
-            if direction == .previous {
-                await backgroundRealm.execute { realm in
-                    let freshFolder = folder.fresh(using: realm)
+        switch direction {
+        case .previous:
+            return await backgroundRealm.execute { realm in
+                let freshFolder = folder.fresh(using: realm)
+                if messagesUids.addedShortUids.count < Constants.pageSize || messagesUids.addedShortUids.contains("1") {
                     try? realm.safeWrite {
                         freshFolder?.isHistoryComplete = true
                         freshFolder?.remainingOldMessagesToFetch = 0
                     }
+                    return false
+                } else {
+                    try? realm.safeWrite {
+                        freshFolder?.remainingOldMessagesToFetch -= Constants.pageSize
+                    }
+                    return true
+                }
+            }
+        case .following:
+            if paginationInfo == nil {
+                await backgroundRealm.execute { realm in
+                    let freshFolder = folder.fresh(using: realm)
+                    try? realm.safeWrite {
+                        freshFolder?.resetHistoryInfo()
+                    }
                 }
             }
-            return false
+        default:
+            break
         }
-        return true
+        return messagesUids.addedShortUids.count == Constants.pageSize
     }
 
     private func handleMessagesUids(messageUids: MessagesUids, folder: Folder) async throws {
diff --git a/MailCore/Models/Folder.swift b/MailCore/Models/Folder.swift
index 8eb961b14..962f35331 100644
--- a/MailCore/Models/Folder.swift
+++ b/MailCore/Models/Folder.swift
@@ -191,6 +191,11 @@ public class Folder: Object, Codable, Comparable, Identifiable {
         unreadCount = threads.where { $0.unseenMessages > 0 }.count
     }
 
+    public func resetHistoryInfo() {
+        remainingOldMessagesToFetch = Constants.messageQuantityLimit
+        isHistoryComplete = false
+    }
+
     public func isParent(of folder: Folder) -> Bool {
         let myComponents = path.components(separatedBy: separator)
         let folderComponents = folder.path.components(separatedBy: separator)