download taler-wallet-embedded.js in build and init backend

1 files changed, 130 insertions, 0 deletions

diff --git a/Taler/WalletBackend.swift b/Taler/WalletBackend.swift
new file mode 100644
index 0000000..5a28371
--- /dev/null
+++ b/Taler/WalletBackend.swift
@@ -0,0 +1,130 @@
+/*
+ * This file is part of GNU Taler
+ * (C) 2021 Taler Systems S.A.
+ *
+ * GNU Taler is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3, or (at your option) any later version.
+ *
+ * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+import Foundation
+import iono
+
+protocol WalletBackendRequest {
+    associatedtype Args: Encodable
+    
+    func operation() -> String
+    func args() -> Args
+}
+
+fileprivate struct WalletBackendRequestData<T: WalletBackendRequest>: Encodable {
+    var operation: String
+    var id: Int
+    var args: T.Args
+    
+    init(request: T, id: Int) {
+        operation = request.operation()
+        self.id = id
+        args = request.args()
+    }
+}
+
+fileprivate struct WalletBackendInitRequest: WalletBackendRequest {
+    struct RequestArgs: Encodable {
+        var persistentStoragePath: String
+    }
+    typealias Args = RequestArgs
+    private var requestArgs: RequestArgs
+    
+    init(persistentStoragePath: String) {
+        requestArgs = RequestArgs(persistentStoragePath: persistentStoragePath)
+    }
+    
+    func operation() -> String {
+        return "init"
+    }
+    
+    func args() -> Args {
+        return requestArgs
+    }
+}
+
+fileprivate struct WalletBackendGetTransactionsRequest: WalletBackendRequest {
+    struct RequestArgs: Encodable {
+        
+    }
+    typealias Args = RequestArgs
+    private var requestArgs: RequestArgs
+    
+    init() {
+        requestArgs = RequestArgs()
+    }
+    
+    func operation() -> String {
+        return "getTransactions"
+    }
+    
+    func args() -> Args {
+        return requestArgs
+    }
+}
+
+enum WalletBackendError: Error {
+    case serializationError
+}
+
+class WalletBackend: IonoMessageHandler {
+    private var iono: Iono
+    private var requestsMade: Int
+    
+    init() {
+        iono = Iono()
+        requestsMade = 0
+        
+        iono.messageHandler = self
+        
+        let js_path = URL(fileURLWithPath: Bundle.main.path(forResource: "taler-wallet-embedded", ofType: "js")!)
+        do {
+            let js = try String(contentsOf: js_path, encoding: .utf8)
+            iono.putModuleCode(modName: "@gnu-taler/taler-wallet-embedded", code: js)
+            iono.evalNodeCode(source: "require('iono');")
+            iono.evalNodeCode(source: "tw = require('@gnu-taler/taler-wallet-embedded');")
+            iono.evalNodeCode(source: "tw.installNativeWalletListener();")
+        } catch {
+
+        }
+        
+        // Send the init message
+        let documentUrls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
+        if (documentUrls.count > 0) {
+            var storageDir = documentUrls[0]
+            storageDir.appendPathComponent("talerwalletdb-v30", isDirectory: false)
+            storageDir.appendPathExtension("json")
+            try! sendRequest(request: WalletBackendInitRequest(persistentStoragePath: storageDir.path))
+        }
+        //try! sendRequest(request: WalletBackendGetTransactionsRequest())
+    }
+    
+    func handleMessage(message: String) {
+        print("received message \(message)")
+    }
+    
+    func sendRequest<T: WalletBackendRequest>(request: T) throws {
+        let data = WalletBackendRequestData<T>(request: request, id: requestsMade)
+        requestsMade += 1
+        do {
+            let encoded = try JSONEncoder().encode(data)
+            guard let jsonString = String(data: encoded, encoding: .utf8) else { throw WalletBackendError.serializationError }
+            iono.sendMessage(message: jsonString)
+        } catch {
+            throw WalletBackendError.serializationError
+        }
+    }
+}