session-ios/SignalUtilitiesKit/Utilities/AppSetup.swift

// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.

import Foundation
import GRDB
import SDWebImageWebPCoder
import SessionUIKit
import SessionNetworkingKit
import SessionMessagingKit
import SessionUtilitiesKit

public enum AppSetup {
    public static func setupEnvironment(
        requestId: String? = nil,
        appSpecificBlock: (() -> ())? = nil,
        migrationProgressChanged: ((CGFloat, TimeInterval) -> ())? = nil,
        migrationsCompletion: @escaping (Result<Void, Error>) -> (),
        using dependencies: Dependencies
    ) {
        var backgroundTask: SessionBackgroundTask? = SessionBackgroundTask(label: #function, using: dependencies)
        
        DispatchQueue.global(qos: .userInitiated).async {
            // Order matters here.
            //
            // All of these "singletons" should have any dependencies used in their
            // initializers injected.
            dependencies[singleton: .backgroundTaskManager].startObservingNotifications()
            
            // Attachments can be stored to NSTemporaryDirectory()
            // If you receive a media message while the device is locked, the download will fail if
            // the temporary directory is NSFileProtectionComplete
            try? dependencies[singleton: .fileManager].protectFileOrFolder(
                at: NSTemporaryDirectory(),
                fileProtectionType: .completeUntilFirstUserAuthentication
            )
            
            // Need to register the WebP coder for encoding purposes
            SDImageCodersManager.shared.addCoder(SDImageWebPCoder.shared)

            SessionEnvironment.shared = SessionEnvironment(
                audioSession: OWSAudioSession(),
                proximityMonitoringManager: OWSProximityMonitoringManagerImpl(using: dependencies),
                windowManager: OWSWindowManager(default: ())
            )
            appSpecificBlock?()
            
            runPostSetupMigrations(
                requestId: requestId,
                backgroundTask: backgroundTask,
                migrationProgressChanged: migrationProgressChanged,
                migrationsCompletion: migrationsCompletion,
                using: dependencies
            )
            
            // The 'if' is only there to prevent the "variable never read" warning from showing
            if backgroundTask != nil { backgroundTask = nil }
        }
    }
    
    public static func runPostSetupMigrations(
        requestId: String? = nil,
        backgroundTask: SessionBackgroundTask? = nil,
        migrationProgressChanged: ((CGFloat, TimeInterval) -> ())? = nil,
        migrationsCompletion: @escaping (Result<Void, Error>) -> (),
        using dependencies: Dependencies
    ) {
        var backgroundTask: SessionBackgroundTask? = (backgroundTask ?? SessionBackgroundTask(label: #function, using: dependencies))
        
        dependencies[singleton: .storage].perform(
            migrations: SNMessagingKit.migrations,
            onProgressUpdate: migrationProgressChanged,
            onComplete: { originalResult in
                // Now that the migrations are complete there are a few more states which need
                // to be setup
                typealias UserInfo = (
                    sessionId: SessionId,
                    ed25519SecretKey: [UInt8],
                    dumpSessionIds: Set<SessionId>,
                    unreadCount: Int?
                )
                dependencies[singleton: .storage].readAsync(
                    retrieve: { db -> UserInfo? in
                        guard let ed25519KeyPair: KeyPair = Identity.fetchUserEd25519KeyPair(db) else {
                            return nil
                        }
                        
                        /// Cache the users session id so we don't need to fetch it from the database every time
                        dependencies.mutate(cache: .general) {
                            $0.setSecretKey(ed25519SecretKey: ed25519KeyPair.secretKey)
                        }
                        
                        /// Load the `libSession` state into memory
                        let userSessionId: SessionId = dependencies[cache: .general].sessionId
                        let cache: LibSession.Cache = LibSession.Cache(
                            userSessionId: userSessionId,
                            using: dependencies
                        )
                        cache.loadState(db, requestId: requestId)
                        dependencies.set(cache: .libSession, to: cache)
                        
                        return (
                            userSessionId,
                            ed25519KeyPair.secretKey,
                            cache.allDumpSessionIds,
                            try? Interaction.fetchAppBadgeUnreadCount(db, using: dependencies)
                        )
                    },
                    completion: { result in
                        switch result {
                            case .failure, .success(.none): break
                            case .success(.some(let userInfo)):
                                /// Save the `UserMetadata` and replicate `ConfigDump` data if needed
                                try? dependencies[singleton: .extensionHelper].saveUserMetadata(
                                    sessionId: userInfo.sessionId,
                                    ed25519SecretKey: userInfo.ed25519SecretKey,
                                    unreadCount: userInfo.unreadCount
                                )
                                
                                Task.detached(priority: .medium) {
                                    dependencies[singleton: .extensionHelper].replicateAllConfigDumpsIfNeeded(
                                        userSessionId: userInfo.sessionId,
                                        allDumpSessionIds: userInfo.dumpSessionIds
                                    )
                                }
                        }
                        
                        /// Ensure any recurring jobs are properly scheduled
                        dependencies[singleton: .jobRunner].scheduleRecurringJobsIfNeeded()
                        
                        /// Callback that the migrations have completed
                        migrationsCompletion(originalResult)
                        
                        /// The 'if' is only there to prevent the "variable never read" warning from showing
                        if backgroundTask != nil { backgroundTask = nil }
                    }
                )
            }
        )
    }
}