taler-ios

WalletModel.swift (20925B)

---

 /*
  * This file is part of GNU Taler, ©2022-25 Taler Systems S.A.
  * See LICENSE.md
  */
 /**
  * @author Marc Stibane
  */
 import Foundation
 import taler_swift
 import SymLog
 import os.log
 
 enum InsufficientBalanceHint: String, Codable {
     /// Merchant doesn't accept money from exchange(s) that the wallet supports
     case merchantAcceptInsufficient = "merchant-accept-insufficient"
     /// Merchant accepts funds from a matching exchange, but the funds can't be deposited with the wire method
     case merchantDepositInsufficient = "merchant-deposit-insufficient"
     /// While in principle the balance is sufficient, the age restriction on coins causes the spendable balance to be insufficient
     case ageRestricted = "age-restricted"
     /// Wallet has enough available funds, but the material funds are insufficient
     /// Usually because there is a pending refresh operation
     case walletBalanceMaterialInsufficient = "wallet-balance-material-insufficient"
     /// The wallet simply doesn't have enough available funds
     case walletBalanceAvailableInsufficient = "wallet-balance-available-insufficient"
     /// Exchange is missing the global fee configuration, thus fees are unknown
     /// and funds from this exchange can't be used for p2p payments
     case exchangeMissingGlobalFees = "exchange-missing-global-fees"
     /// Even though the balance looks sufficient for the instructed amount,
     /// the fees can be covered by neither the merchant nor the remaining wallet  balance
     case feesNotCovered = "fees-not-covered"
 
     func localizedCause(_ currency: String) -> String {
         switch self {
             case .merchantAcceptInsufficient:
                 String(localized: "payment_balance_insufficient_hint_merchant_accept_insufficient",
                     defaultValue: "Merchant doesn't accept money from one or more providers in this wallet")
             case .merchantDepositInsufficient:
                 String(localized: "payment_balance_insufficient_hint_merchant_deposit_insufficient",
                     defaultValue: "Merchant doesn't accept the wire method of the provider, this likely means it is misconfigured")
             case .ageRestricted:
                 String(localized: "payment_balance_insufficient_hint_age_restricted",
                     defaultValue: "Purchase not possible due to age restriction")
             case .walletBalanceMaterialInsufficient:
                 String(localized: "payment_balance_insufficient_hint_wallet_balance_material_insufficient",
                     defaultValue: "Some of the digital cash needed for this purchase is currently unavailable")
             case .walletBalanceAvailableInsufficient:
                 String(localized: "payment_balance_insufficient_max",
                     defaultValue: "Balance insufficient! You don't have enough \(currency).")
             case .exchangeMissingGlobalFees:
                 String(localized: "payment_balance_insufficient_hint_exchange_missing_global_fees",
                     defaultValue: "Provider is missing the global fee configuration, this likely means it is misconfigured")
             case .feesNotCovered:
                 String(localized: "payment_balance_insufficient_hint_fees_not_covered",
                     defaultValue: "Not enough funds to pay the provider fees not covered by the merchant")
         }
     }
 }
 
 struct InsufficientBalanceDetailsPerExchange: Codable, Hashable {
     var balanceAvailable: Amount
     var balanceMaterial: Amount
     var balanceExchangeDepositable: Amount
     var balanceAgeAcceptable: Amount
     var balanceReceiverAcceptable: Amount
     var balanceReceiverDepositable: Amount
     var maxEffectiveSpendAmount: Amount
     /// Exchange doesn't have global fees configured for the relevant year, p2p payments aren't possible.
     var missingGlobalFees: Bool
 }
 
 ///  Detailed reason for why the wallet's balance is insufficient.
 struct PaymentInsufficientBalanceDetails: Codable, Hashable {
     /// Amount requested by the merchant.
     var amountRequested: Amount
     var causeHint: InsufficientBalanceHint?
     /// Balance of type "available" (see balance.ts for definition).
     var balanceAvailable: Amount
     /// Balance of type "material" (see balance.ts for definition).
     var balanceMaterial: Amount
     /// Balance of type "age-acceptable" (see balance.ts for definition).
     var balanceAgeAcceptable: Amount
     /// Balance of type "merchant-acceptable" (see balance.ts for definition).
     var balanceReceiverAcceptable: Amount
     /// Balance of type ...
     var balanceReceiverDepositable: Amount
     var balanceExchangeDepositable: Amount
     /// Maximum effective amount that the wallet can spend, when all fees are paid by the wallet.
     var maxEffectiveSpendAmount: Amount
     var perExchange: [String : InsufficientBalanceDetailsPerExchange]
 }
 // MARK: -
 struct TalerErrorDetail: Codable, Hashable {
     /// Numeric error code defined in the GANA gnu-taler-error-codes registry.
     var code: Int
     // all other fields are optional:
     var when: Timestamp?
     /// English description of the error code.
     var hint: String?
 
     /// Error details, type depends on `talerErrorCode`.
     var detail: String?
 
     /// HTTPError
     var requestUrl: String?
     var requestMethod: String?
     var httpStatusCode: Int?
     var stack: String?
 
     var insufficientBalanceDetails: PaymentInsufficientBalanceDetails?
 }
 // MARK: -
 /// Communicate with wallet-core
 final class WalletModel: ObservableObject, Sendable {
     public static let shared = WalletModel()
     let logger = Logger(subsystem: "net.taler.gnu", category: "WalletModel")
 
     @Published var error2: ErrorData? = nil
 
     @MainActor func setError(_ theError: Error?) {
         if let theError {
             self.error2 = .error(theError)
         } else {
             self.error2 = nil
         }
     }
     @MainActor func setMessage(_ title: String,_ theMessage: String?) {
         if let theMessage {
             self.error2 = .message(title: title, message: theMessage)
         } else {
             self.error2 = nil
         }
     }
 
     func sendRequest<T: WalletBackendFormattedRequest> (_ request: T, viewHandles: Bool = false, asJSON: Bool = false)
       async throws -> T.Response {    // T for any Thread
 #if !DEBUG
         logger.log("sending: \(request.operation(), privacy: .public)")
 #endif
         let sendTime = Date.now
         do {
             let (response, id) = try await WalletCore.shared.sendFormattedRequest(request, asJSON: asJSON)
 #if !DEBUG
             let timeUsed = Date.now - sendTime
             logger.log("received: \(request.operation(), privacy: .public) (\(id, privacy: .public)) after \(timeUsed.milliseconds, privacy: .public) ms")
 #endif
             return response
         } catch {       // rethrows
             let timeUsed = Date.now - sendTime
             logger.error("\(request.operation(), privacy: .public) failed after \(timeUsed.milliseconds, privacy: .public) ms\n\(error, privacy: .public)")
             if !viewHandles {
                 // TODO: symlog + controller sound
                 await setError(error)
             }
             throw error
         }
     }
 }
 // MARK: -
 /// A request to tell wallet-core about the network.
 fileprivate struct ApplicationResumedRequest: WalletBackendFormattedRequest {
     struct Response: Decodable {}
     func operation() -> String { "hintApplicationResumed" }
     func args() -> Args { Args() }
 
     struct Args: Encodable {}                           // no arguments needed
 }
 
 fileprivate struct NetworkAvailabilityRequest: WalletBackendFormattedRequest {
     struct Response: Decodable {}
     func operation() -> String { "hintNetworkAvailability" }
     func args() -> Args { Args(isNetworkAvailable: isNetworkAvailable) }
 
     var isNetworkAvailable: Bool
 
     struct Args: Encodable {
         var isNetworkAvailable: Bool
     }
 }
 
 extension WalletModel {
     func hintNetworkAvailabilityT(_ isNetworkAvailable: Bool = false) async {
         // T for any Thread
         let request = NetworkAvailabilityRequest(isNetworkAvailable: isNetworkAvailable)
         _ = try? await sendRequest(request)
     }
     func hintApplicationResumedT() async {
         // T for any Thread
         let request = ApplicationResumedRequest()
         _ = try? await sendRequest(request)
     }
 }
 // MARK: -
 /// A request to get a wallet transaction by ID.
 fileprivate struct GetTransactionById: WalletBackendFormattedRequest {
     typealias Response = TalerTransaction
     func operation() -> String { "getTransactionById" }
     func args() -> Args { Args(transactionId: transactionId, includeContractTerms: includeContractTerms) }
 
     var transactionId: String
     var includeContractTerms: Bool?
 
     struct Args: Encodable {
         var transactionId: String
         var includeContractTerms: Bool?
     }
 }
 
 fileprivate struct JSONTransactionById: WalletBackendFormattedRequest {
     typealias Response = String
     func operation() -> String { "getTransactionById" }
     func args() -> Args { Args(transactionId: transactionId, includeContractTerms: includeContractTerms) }
 
     var transactionId: String
     var includeContractTerms: Bool?
 
     struct Args: Encodable {
         var transactionId: String
         var includeContractTerms: Bool?
     }
 }
 
 extension WalletModel {
     /// get the specified transaction from Wallet-Core. No networking involved
     nonisolated func getTransactionById(_ transactionId: String, includeContractTerms: Bool? = nil, viewHandles: Bool = false)
       async throws -> TalerTransaction {
         let request = GetTransactionById(transactionId: transactionId, includeContractTerms: includeContractTerms)
         return try await sendRequest(request, viewHandles: viewHandles)
     }
     nonisolated func jsonTransactionById(_ transactionId: String, includeContractTerms: Bool? = nil, viewHandles: Bool = false)
       async throws -> String {
         let request = JSONTransactionById(transactionId: transactionId, includeContractTerms: includeContractTerms)
         return try await sendRequest(request, viewHandles: viewHandles, asJSON: true)
     }
 }
 // MARK: -
 /// The info returned from Wallet-core init
 struct VersionInfo: Decodable {
     var implementationSemver: String?
     var implementationGitHash: String?
     var version: String
     var exchange: String
     var merchant: String
     var bank: String
 }
 // MARK: -
 fileprivate struct Testing: Encodable {
     var denomselAllowLate: Bool
     var devModeActive: Bool
     var insecureTrustExchange: Bool
     var preventThrottling: Bool
     var skipDefaults: Bool
     var emitObservabilityEvents: Bool
     // more to come...
 
     init(devModeActive: Bool) {
         self.denomselAllowLate = false
         self.devModeActive = devModeActive
         self.insecureTrustExchange = false
         self.preventThrottling = false
         self.skipDefaults = false
         self.emitObservabilityEvents = devModeActive
     }
 }
 
 fileprivate struct Builtin: Encodable {
     var exchanges: [String]
     // more to come...
 }
 
 fileprivate struct Config: Encodable {
     var testing: Testing
     var builtin: Builtin
 }
 // MARK: -
 ///  A request to re-configure Wallet-core
 fileprivate struct ConfigRequest: WalletBackendFormattedRequest {
     var setTesting: Bool
 
     func operation() -> String { "setWalletRunConfig" }
     func args() -> Args {
         let testing = Testing(devModeActive: setTesting)
         let builtin = Builtin(exchanges: [])
         let config = Config(testing: testing, builtin: builtin)
         return Args(config: config)
     }
 
     struct Args: Encodable {
         var config: Config
     }
     struct Response: Decodable {
         var versionInfo: VersionInfo
     }
 }
 
 extension WalletModel {
     /// initalize Wallet-Core. Will do networking
     @discardableResult
     nonisolated func setConfig(setTesting: Bool) async throws -> VersionInfo {
         let request = ConfigRequest(setTesting: setTesting)
         let response = try await sendRequest(request)
         return response.versionInfo
     }
 }
 // MARK: -
 ///  A request to initialize Wallet-core
 fileprivate struct InitRequest: WalletBackendFormattedRequest {
     var persistentStoragePath: String
     var setTesting: Bool
 
     func operation() -> String { "init" }
     func args() -> Args {
         let testing = Testing(devModeActive: setTesting)
         let builtin = Builtin(exchanges: [])
         let config = Config(testing: testing, builtin: builtin)
         return Args(persistentStoragePath: persistentStoragePath,
 //                       cryptoWorkerType: "sync",
                                  logLevel: "info",  // trace, info, warn, error, none
                                    config: config,
                          useNativeLogging: true)
     }
 
     struct Args: Encodable {
         var persistentStoragePath: String
 //        var cryptoWorkerType: String
         var logLevel: String
         var config: Config
         var useNativeLogging: Bool
     }
     struct Response: Decodable {
         var versionInfo: VersionInfo
     }
 }
 
 extension WalletModel {
     /// initalize Wallet-Core. Might do networking
     nonisolated func initWalletCore(setTesting: Bool, viewHandles: Bool = false) async throws -> VersionInfo {
         let dbPath = try dbPath()
 //        logger.debug("dbPath: \(dbPath)")
         let request = InitRequest(persistentStoragePath: dbPath, setTesting: setTesting)
         let response = try await sendRequest(request, viewHandles: viewHandles)    // no Delay
         return response.versionInfo
     }
 
     private func dbUrl(_ folder: URL) -> URL {
         let DATABASE = "talerwalletdb-v30"
         let dbUrl = folder.appendingPathComponent(DATABASE, isDirectory: false)
                           .appendingPathExtension("sqlite3")
         return dbUrl
     }
 
     private func checkAppSupport(_ url: URL) {
         let fileManager = FileManager.default
         var resultStorage: ObjCBool = false
 
         if !fileManager.fileExists(atPath: url.path, isDirectory: &resultStorage) {
             do {
                 try fileManager.createDirectory(at: url, withIntermediateDirectories: true, attributes: nil)
                 logger.debug("created \(url.path)")
             } catch {
                 logger.error("creation failed \(error.localizedDescription)")
             }
         } else {
 //            logger.debug("\(url.path) exists")
         }
     }
 
     private func migrate(from source: URL, to target: URL) {
         let fileManager = FileManager.default
         let sourceUrl = dbUrl(source)
         let sourcePath = sourceUrl.path
         let targetUrl = dbUrl(target)
         let targetPath = targetUrl.path
 
         checkAppSupport(target)
         if fileManager.fileExists(atPath: sourcePath) {
             do {
                 try fileManager.moveItem(at: sourceUrl, to: targetUrl)
                 logger.debug("migrate: moved to \(target.path)")
             } catch {
                 logger.error("migrate: move failed \(error.localizedDescription)")
             }
         } else {
             logger.debug("migrate: nothing to do, no db at \(sourcePath)")
         }
 
         if fileManager.fileExists(atPath: targetPath) {
 //            logger.debug("found db at \(targetPath)")
         } else {
             logger.debug("migrate: nothing to do, no db at \(targetPath)")
         }
     }
 
     private func dbPath() throws -> String {
         if let docDirUrl = URL.docDirUrl {
             if let appSupport = URL.appSuppUrl {
 #if DEBUG || GNU_TALER
                 migrate(from: appSupport, to: docDirUrl)
                 return docDirUrl.path(withSlash: true)
 #else // TALER_WALLET or TALER_NIGHTLY
                 migrate(from: docDirUrl, to: appSupport)
                 return appSupport.path(withSlash: true)
 #endif
             } else { // should never happen
                 logger.error("dbPath: No applicationSupportDirectory")
             }
         } else { // should never happen
             logger.error("dbPath: No documentDirectory")
         }
         throw WalletBackendError.initializationError
     }
 
     private func cachePath() throws -> String {
         let fileManager = FileManager.default
         if let cachesURL = fileManager.urls(for: .cachesDirectory, in: .userDomainMask).first {
             let cacheURL = cachesURL.appendingPathComponent("cache.json")
             let cachePath = cacheURL.path
             logger.debug("cachePath: \(cachePath)")
 
             if !fileManager.fileExists(atPath: cachePath) {
                 let contents = Data()       /// Initialize an empty `Data`.
                 fileManager.createFile(atPath: cachePath, contents: contents)
                 print("❗️ File \(cachePath) created")
             } else {
                 print("❗️ File \(cachePath) already exists")
             }
 
             return cachePath
         } else {    // should never happen
             logger.error("cachePath: No cachesDirectory")
             throw WalletBackendError.initializationError
         }
     }
 }
 // MARK: -
 ///  A request to reset Wallet-core to a virgin DB. WILL DESTROY ALL COINS
 fileprivate struct ResetRequest: WalletBackendFormattedRequest {
     func operation() -> String { "clearDb" }
     func args() -> Args { Args() }
 
     struct Args: Encodable {}                           // no arguments needed
     struct Response: Decodable {}
 }
 
 extension WalletModel {
     /// reset Wallet-Core
     nonisolated func resetWalletCore(viewHandles: Bool = false) async throws {
         let request = ResetRequest()
         _ = try await sendRequest(request, viewHandles: viewHandles)
     }
 }
 // MARK: -
 fileprivate struct ExportDbToFile: WalletBackendFormattedRequest {
     func operation() -> String { "exportDbToFile" }
     func args() -> Args { Args(directory: directory, stem: stem, forceFormat: "json") }
 
     var directory: String
     var stem: String
     struct Args: Encodable {
         var directory: String
         var stem: String
         var forceFormat: String
     }
     struct Response: Decodable, Sendable {              // path of the copied DB
         var path: String
     }
 }
 
 fileprivate struct ImportDbFromFile: WalletBackendFormattedRequest {
     func operation() -> String { "importDbFromFile" }
     func args() -> Args { Args(path: path ) }
 
     var path: String
     struct Args: Encodable {
         var path: String
     }
     struct Response: Decodable {}
 }
 
 fileprivate struct GetDiagnostics: WalletBackendFormattedRequest {
     func operation() -> String { "getDiagnostics" }
     func args() -> Args { Args() }
     struct Args: Encodable {}                           // no arguments needed
     typealias Response = String
 }
 
 fileprivate struct GetPerformanceStats: WalletBackendFormattedRequest {
     func operation() -> String { "testingGetPerformanceStats" }
     func args() -> Args { Args() }
     struct Args: Encodable {}                           // no arguments needed
     typealias Response = String
 }
 
 extension WalletModel {
     /// export, import DB, get diagnostics
     nonisolated func exportDbToFile(stem: String, viewHandles: Bool = false)
       async throws -> String? {
         if let docDirUrl = URL.docDirUrl {
             let dbPath = docDirUrl.path(withSlash: false)
             let request = ExportDbToFile(directory: dbPath, stem: stem)
     print(dbPath, stem)
             let response = try await sendRequest(request, viewHandles: viewHandles)
             return response.path
         } else {
             return nil
         }
     }
     nonisolated func importDbFromFile(path: String, viewHandles: Bool = false)
       async throws {
         let request = ImportDbFromFile(path: path)
         _ = try await sendRequest(request, viewHandles: viewHandles)
     }
     nonisolated func getDiagnostics(viewHandles: Bool = false)
       async throws -> String {
         let request = GetDiagnostics()
         let response = try await sendRequest(request, viewHandles: viewHandles, asJSON: true)
         return response
     }
     nonisolated func getPerformanceStats(viewHandles: Bool = false)
     async throws -> String {
         let request = GetPerformanceStats()
         let response = try await sendRequest(request, viewHandles: viewHandles, asJSON: true)
         return response
     }
 }
 // MARK: -
 fileprivate struct DevExperimentRequest: WalletBackendFormattedRequest {
     func operation() -> String { "applyDevExperiment" }
     func args() -> Args { Args(devExperimentUri: talerUri) }
 
     var talerUri: String
 
     struct Args: Encodable {
         var devExperimentUri: String
     }
     struct Response: Decodable {}
 }
 
 extension WalletModel {
     /// tell wallet-core to mock new transactions
     nonisolated func devExperimentT(talerUri: String, viewHandles: Bool = false) async throws {
         // T for any Thread
         let request = DevExperimentRequest(talerUri: talerUri)
         _ = try await sendRequest(request, viewHandles: viewHandles)
     }
 }