Add developer option for clearing the application cache (#852)

* Add developer option for clearing the application cache

* Tweaks following code review

ElementX/Sources/Services/UserSession/UserSessionFlowCoordinator.swift

@@ -19,6 +19,7 @@ import SwiftUI
 
 enum UserSessionFlowCoordinatorAction {
     case signOut
+    case clearCache
 }
 
 class UserSessionFlowCoordinator: CoordinatorProtocol {
@@ -304,6 +305,8 @@ class UserSessionFlowCoordinator: CoordinatorProtocol {
             case .logout:
                 self.navigationSplitCoordinator.setSheetCoordinator(nil)
                 self.callback?(.signOut)
+            case .clearCache:
+                self.callback?(.clearCache)
             }
         }
         

ElementX/Sources/Services/UserSession/UserSessionStore.swift

@@ -21,6 +21,7 @@ import MatrixRustSDK
 class UserSessionStore: UserSessionStoreProtocol {
     private let keychainController: KeychainControllerProtocol
     private let backgroundTaskService: BackgroundTaskServiceProtocol
+    private let cachesFolderName = "matrix-sdk-state"
     
     /// Whether or not there are sessions in the store.
     var hasSessions: Bool { !keychainController.restorationTokens().isEmpty }
@@ -90,6 +91,11 @@ class UserSessionStore: UserSessionStoreProtocol {
         deleteSessionDirectory(for: userID)
     }
     
+    func clearCacheFor(userSession: UserSessionProtocol) {
+        let userID = userSession.clientProxy.userID
+        deleteCachesFolder(for: userID)
+    }
+    
     // MARK: - Private
     
     private func buildUserSessionWithClient(_ clientProxy: ClientProxyProtocol) -> UserSessionProtocol {
@@ -140,9 +146,15 @@ class UserSessionStore: UserSessionStoreProtocol {
     }
     
     private func deleteSessionDirectory(for userID: String) {
-        // Rust sanitises the user ID replacing invalid characters with an _
-        let sanitisedUserID = userID.replacingOccurrences(of: ":", with: "_")
-        let url = baseDirectory.appendingPathComponent(sanitisedUserID)
+        do {
+            try FileManager.default.removeItem(at: basePath(for: userID))
+        } catch {
+            MXLog.failure("Failed deleting the session data: \(error)")
+        }
+    }
+    
+    private func deleteCachesFolder(for userID: String) {
+        let url = basePath(for: userID).appendingPathComponent(cachesFolderName)
         
         do {
             try FileManager.default.removeItem(at: url)
@@ -150,4 +162,11 @@ class UserSessionStore: UserSessionStoreProtocol {
             MXLog.failure("Failed deleting the session data: \(error)")
         }
     }
+    
+    #warning("We should move this and the caches folder path to the rust side")
+    private func basePath(for userID: String) -> URL {
+        // Rust sanitises the user ID replacing invalid characters with an _
+        let sanitisedUserID = userID.replacingOccurrences(of: ":", with: "_")
+        return baseDirectory.appendingPathComponent(sanitisedUserID)
+    }
 }

ElementX/Sources/Services/UserSession/UserSessionStoreProtocol.swift

@@ -45,4 +45,7 @@ protocol UserSessionStoreProtocol {
     
     /// Logs out of the specified session.
     func logout(userSession: UserSessionProtocol)
+    
+    /// Clears our all the matrix sdk state data for the specified session
+    func clearCacheFor(userSession: UserSessionProtocol)
 }