prepare sending and receiving files

src/Model/Global/fileTransferModel.ts

@@ -1,14 +1,21 @@
 // this file is responsible for sending and handling files.
 
+import { decryptString, encryptString } from "../Utility/crypto";
+import { generateRandomToken, parse, stringify } from "../Utility/utility";
+
 import ConnectionModel from "./connectionModel";
+import { Message } from "udn-frontend";
 import StorageModel from "./storageModel";
-import { generateRandomToken } from "../Utility/utility";
+import { checkMatchesObjectStructure } from "../Utility/typeSafety";
 
 export default class FileTransferModel {
   storageModel: StorageModel;
   connectionModel: ConnectionModel;
 
-  // methods
+  // data
+  transferData: TransferData | undefined;
+
+  // general
   generateTransferData = (): TransferData => {
     return {
       channel: generateRandomToken(2),
@@ -16,10 +23,68 @@ export default class FileTransferModel {
     };
   };
 
+  prepareToReceive = (transferData: TransferData) => {
+    this.connectionModel.addChannel(transferData.channel);
+    this.transferData = transferData;
+  };
+
+  // handlers
+  handleMessage = (data: Message): void => {
+    if (this.transferData == undefined) return;
+    if (data.messageChannel != this.transferData.channel) return;
+  };
+
+  handleFile = async (encryptedFileData: string): Promise<void> => {
+    if (this.transferData == undefined) return;
+
+    const decrypted: string = await decryptString(
+      encryptedFileData,
+      this.transferData.key
+    );
+    
+    const parsed: any = parse(decrypted);
+    const isFileData: boolean = checkMatchesObjectStructure(parsed, FileDataReference);
+    if (isFileData == false) return;
+    
+    const fileData: FileData = parsed;
+    this.storageModel.write(fileData.path, fileData.body);
+  };
+
+  // sending
+  sendFiles = (...directoryPaths: string[][]): void => {
+    for (const directoryPath of directoryPaths) {
+      this.storageModel.recurse(directoryPath, (filePath: string[]) => {
+        this.sendFile(filePath);
+      });
+    }
+  };
+
+  sendFile = async (filePath: string[]): Promise<void> => {
+    if (this.transferData == undefined) return;
+    const fileContent: string | null = this.storageModel.read(filePath);
+    if (fileContent == null) return;
+
+    const fileData: FileData = {
+      path: filePath,
+      body: fileContent,
+    };
+    const stringifiedFileData: string = stringify(fileData);
+    const encryptedFileData: string = await encryptString(
+      fileContent,
+      stringifiedFileData
+    );
+    this.connectionModel.sendPlainMessage(
+      this.transferData.channel,
+      encryptedFileData
+    );
+  };
+
   // init
   constructor(storageModel: StorageModel, connectionModel: ConnectionModel) {
     this.storageModel = storageModel;
     this.connectionModel = connectionModel;
+
+    this.connectionModel.messageHandlerManager.addHandler(this.handleMessage);
   }
 }
 
@@ -27,3 +92,13 @@ export interface TransferData {
   channel: string;
   key: string;
 }
+
+export interface FileData {
+  path: string[];
+  body: string;
+}
+
+export const FileDataReference: FileData = {
+  path: [""],
+  body: "",
+};