feat: add getPartFile download

jensen.d.ts

@@ -69,6 +69,7 @@ declare class Jensen {
   getDeviceInfo: (time?: number) => Promise<DeviceInfo>;
   listFiles: (time?: number) => Promise<FileInfo[]>;
   getFile: (fileName: string, length: number, on?: (msg: Uint8Array | 'fail') => void, onprogress?: (size: number) => void) => void;
+  getFilePart: (fileName: string, length: number, on?: (msg: Uint8Array | 'fail') => void, onprogress?: (size: number) => void) => void;
   getFileBlock: (fileName: string, length: number, on?: (msg: Uint8Array | 'fail') => void) => Promise<ReturnStruct['common']>;
   requestFirmwareUpgrade: (vn: number, length: number, time?: number) => Promise<{ result: 'accepted' | 'fail' }>;
   beginBNC: (time?: number) => Promise<ReturnStruct['common']>;

src/utils/jensen.js

@@ -217,7 +217,7 @@ function Jensen(log) {
     current = 'cmd-' + cmd.command + '-' + cmd.index;
     Logger.debug('jensen', 'sendNext', 'command: ' + COMMAND_NAMES[cmd.command] + ', data bytes: ' + data.byteLength);
 
-    self.timewait = cmd.command == TRANSFER_FILE ? 1000 : 10;
+    self.timewait = cmd.command == TRANSFER_FILE || cmd.command == GET_FILE_BLOCK ? 100 : 10;
 
     await device.transferOut(1, data).catch((e) => crash('sendNext', e));
     if (cmd.onprogress) cmd.onprogress(1, 1);
@@ -720,6 +720,39 @@ Jensen.prototype.streaming = async function (filename, length, ondata, onprogres
   this.send(new Command(TRANSFER_FILE).body(fname));
 };
 
+Jensen.prototype.getFilePart = async function (filename, length, ondata, onprogress) {
+  if (typeof length != 'number') throw new Error('parameter `length` required');
+  if (length <= 0) throw new Error('parameter `length` must greater than zero');
+
+  Logger.info('jensen', 'getFilePart', `file download start. filename: ${filename}, length: ${length} `);
+
+  let data = [];
+  data.push((length >> 24) & 0xff);
+  data.push((length >> 16) & 0xff);
+  data.push((length >> 8) & 0xff);
+  data.push((length >> 0) & 0xff);
+  for (let i = 0; i < filename.length; i++) data.push(filename.charCodeAt(i));
+
+  let flen = 0;
+  let handler = (msg) => {
+    if (msg != null) {
+      flen += msg.body.length || msg.body.byteLength;
+      ondata(msg.body);
+      Logger.info('jensen', 'getFilePart length', `${length} ${flen}`);
+      if (flen >= length) {
+        Logger.info('jensen', 'getFilePart', 'file download finish.');
+        return 'OK';
+      }
+    } else {
+      Logger.info('jensen', 'getFilePart', 'file download fail.');
+      ondata('fail');
+    }
+  };
+  this.onreceive = onprogress;
+  Jensen.registerHandler(GET_FILE_BLOCK, handler);
+  this.send(new Command(GET_FILE_BLOCK).body(data));
+};
+
 Jensen.prototype.getFile = async function (filename, length, ondata, onprogress) {
   if (typeof length != 'number') throw new Error('parameter `length` required');
   if (length <= 0) throw new Error('parameter `length` must greater than zero');