refactor

impl.ts

@@ -1,6 +1,6 @@
 import "./shim.ts";
 
-import { Commands } from "./datatypes.js";
+import { ControlCommands, Commands, ccDest } from "./datatypes.js";
 import { Session } from "./server.js";
 import { XqBytesEnc } from "./func_replacements.js";
 import { hexdump } from "./hexdump.js";
@@ -29,97 +29,59 @@ const DrwHdr = (cmd: number, len: number, d1_or_d2: 0xd1 | 0xd2, m_chan: number,
   retret.add(6).writeU16(pkt_id);
   return retret;
 };
-export const SendDevStatus = (session: Session): DataView => {
-  let buf = new DataView(new Uint8Array(0x14).buffer);
 
-  /*
-00000000  f1 d0 00 10 d1 00 00 c3 11 0a 08 10 04 00 00 00  ................
-00000010  68 66 6b 67                                      hfkg
-*/
-  let bytes = [
-    0xf1,
-    0xd0,
-    0x00, // len? lower values= no response, larger values = 1 frame then kicked
-    0x10, // len
-    0xd1, // ?
-    0x00, // chan
-    session.outgoingCommandId >> 8,
-    session.outgoingCommandId,
-    0x11,
-    0x0a,
-    0x08,
-    0x10,
-    0x04, // len
-    0x00, // len
-    0x00, // dst
-    0x00, // dst
-    session.ticket[0],
-    session.ticket[1],
-    session.ticket[2],
-    session.ticket[3],
-  ];
-  buf.writeByteArray(bytes);
-  return buf;
+const makeDataReadWrite = (session: Session, command: number, data: DataView | null): DataView => {
+  const DRW_HEADER_LEN = 0x10;
+  const TOKEN_LEN = 0x4;
+  const CHANNEL = 0;
+  const START_CMD = 0x110a;
+
+  let pkt_len = DRW_HEADER_LEN + TOKEN_LEN;
+  let payload_len = TOKEN_LEN;
+  let bufCopy: Uint8Array | null = null;
+  if (data) {
+    bufCopy = new Uint8Array(data.buffer);
+    const bufDV = new DataView(bufCopy.buffer);
+    // this mutates the buffer, don't want to mutate the caller
+    XqBytesEnc(bufDV, bufDV.byteLength, 4);
+    pkt_len += bufDV.byteLength;
+    payload_len += bufDV.byteLength;
+  }
+
+  const ret = new DataView(new Uint8Array(pkt_len).buffer);
+  ret.add(0).writeU16(Commands.Drw);
+  ret.add(2).writeU16(pkt_len - 4); // -4 as we ignore the [0xf1, 0xd0, len, len]
+  ret.add(4).writeU8(0xd1); // ?
+  ret.add(5).writeU8(CHANNEL);
+  ret.add(6).writeU16(session.outgoingCommandId);
+  ret.add(8).writeU16(START_CMD);
+  ret.add(10).writeU16(command);
+  ret.add(12).writeU16(u16_swap(payload_len));
+  ret.add(14).writeU16(ccDest[command]);
+  ret.add(16).writeByteArray(session.ticket);
+  if (data) {
+    ret.add(20).writeByteArray(bufCopy);
+  }
+
+  return ret;
+};
+
+export const SendDevStatus = (session: Session): DataView => {
+  return makeDataReadWrite(session, ControlCommands.DevStatus, null);
 };
 
 export const SendStartVideo = (session: Session): DataView => {
-  // TODO: extract SendUsrChk
-  let buf = new DataView(new Uint8Array(0x18).buffer);
-  // console.log(hexdump(DrwHdr(0xf1d0, 0x0114, 0xd1, 0, pkt_id).buffer));
-
-  let bytes = [
-    0xf1,
-    0xd0,
-    0x01, // len? lower values= no response, larger values = 1 frame then kicked
-    0x14, // len
-    0xd1, // ?
-    0x00, // chan
-    session.outgoingCommandId >> 8,
-    session.outgoingCommandId,
-    0x11,
-    0x0a,
-    0x10,
-    0x30,
-    0x08,
-    0x01,
-    0x00,
-    0x00,
-    session.ticket[0],
-    session.ticket[1],
-    session.ticket[2],
-    session.ticket[3],
-    0x01,
-    0x01,
-    0x01,
-    0x01,
-  ];
-  buf.writeByteArray(bytes);
-  return buf;
+  return makeDataReadWrite(session, ControlCommands.StartVideo, null);
 };
-export const SendUsrChk = (username: string, password: string, pkt_id: number): DataView => {
-  // type is char account[0x20]; char password[0x80];
+
+export const SendUsrChk = (session: Session, username: string, password: string): DataView => {
   let buf = new Uint8Array(0x20 + 0x80);
   buf.fill(0);
   let cmd_payload = new DataView(buf.buffer);
+  // type is char account[0x20]; char password[0x80];
   cmd_payload.writeByteArray(str2byte(username));
   cmd_payload.add(0x20).writeByteArray(str2byte(password));
-
-  const start = 0xa11;
-  const dest = 0xff;
-  const cmd = 0x1020; // FIXME ControlCommands.ConnectUser
-  const len = buf.byteLength;
-  let cmdHeader = CmdSndProcHdr(start, cmd, len, dest);
-  let ret = new DataView(new Uint8Array(12 + len).buffer);
-  ret.writeByteArray(new Uint8Array(cmdHeader.buffer));
-  XqBytesEnc(cmd_payload, 0x20 + 0x80, 4);
-  ret.add(12).writeByteArray(new Uint8Array(cmd_payload.buffer));
-
-  // need to encapsulate this into create_Drw(outbuf, 0xd1, param4?, svar1?,
-  // copy_len, inbuf); seems like param4/svar1 are overflowing == maybe '0xa'
-  // and '0x2010'??
-  let retret = DrwHdr(0xf1d0, 8 + 12 + len - 4, 0xd1, 0, pkt_id);
-  retret.add(8).writeByteArray(new Uint8Array(ret.buffer));
-  return retret;
+  return makeDataReadWrite(session, ControlCommands.ConnectUser, cmd_payload);
 };
 
 export const create_P2pRdy = (inbuf: DataView): DataView => {