From 71b21f12756e66a8ae1f6c0504ad17ba0ac2dd0e Mon Sep 17 00:00:00 2001
From: Crawford Comeaux <crawford.comeaux@gmail.com>
Date: Tue, 23 Jun 2015 14:21:46 -0400
Subject: [PATCH] Added support for AMF0 packets

Refactored read()'s core functionality into readData(); added readPacket(), readHeader(), and readMessage(); info object now has isPacket property.
TODO:
[ ] Test changes to read's docstrings
[ ] Write tests for packet support
---
 lib/read.js | 90 +++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 84 insertions(+), 6 deletions(-)

diff --git a/lib/read.js b/lib/read.js
index 0841cd5..e6e2a37 100644
--- a/lib/read.js
+++ b/lib/read.js
@@ -14,22 +14,100 @@ var amf0Types = constants.amf0Types;
 module.exports = read;
 
 /**
- * Reads an AMF object from the specified Buffer at the specified offset.
+ * Reads an AMF object or packet from the specified Buffer at the specified offset.
  *
  * @param {Buffer} buffer The Buffer instance to read from.
- * @param {Object|Number} info "Options" object, or the byte offset to begin reading from.
- * @return {Object|Array} The decoded AMF object.
+ * @param {Object|Number} [info={offset: 0, ispacket: false}] "Options" object, or the byte offset to begin reading from.
+ * @param {Number} [info.offset=0] byte offset to begin reading from.
+ * @param {boolean} [info.isPacket=false] flag specifying if buffer contains a packet or an object
+ * @return {Object|Array} The decoded AMF object or packet.
  * @api public
  */
 
 function read (buffer, info) {
   if ('number' == typeof info) info = { offset: info };
-  if (!info) info = {};
-  if (null == info.offset) info.offset = 0;
-
+  info = info || {} 
+  info.offset = info.offset || 0; 
+  info.isPacket = info.isPacket || false;
   // gets reset to 0 on each `read()` call
   info.byteLength = 0;
 
+  if (info.isPacket) {
+    return readPacket(buffer, info);
+  } else {
+    return readData(buffer, info);
+  }
+}
+
+function readPacket (buffer, info) {
+  var packet = {};
+  var headers = [];
+  var messages = [];
+
+  var offset = info.offset;
+  packet.version = buffer.readUInt16BE(offset);
+  bytesUsed(info,2);
+
+  var headerCount = buffer.readUInt16BE(info.offset);
+  bytesUsed(info,2);
+
+  for (var i = 0, j = headerCount; i < j; i++) {
+    headers.push(readHeader(buffer, info));
+  }
+
+  var messageCount = buffer.readUInt16BE(info.offset);
+  bytesUsed(info,2);
+
+  for (var i = 0, j = messageCount; i < j; i++) {
+    messages.push(readMessage(buffer,info));
+  }
+
+  // headerCount/messageCount aren't stored in the packet
+  // object since they're equal to the length of the arrays.
+  // But maybe that's something worth testing for?
+
+  packet.headers = headers;
+  packet.messages = messages;
+  return packet;
+}
+
+function readHeader (buffer, info) {
+  var headerName = readString(buffer,info);
+  //
+  var mustUnderstand = buffer.readUInt8(info.offset) != 0 ? true : false;
+  bytesUsed(info, 1);
+  var headerLength = buffer.readUInt32BE(info.offset);
+  bytesUsed(info,4);
+
+  var header = {
+    name: headerName,
+    mustUnderstand: mustUnderstand,
+    length: headerLength,
+    // Header payload is just an AMF0 value-type
+    value: readData(buffer, info)
+  }
+
+  return header;
+}
+
+function readMessage (buffer, info) {
+  var targetURI = readString(buffer, info);
+  var responseURI = readString(buffer, info);
+  var messageLength = buffer.readUInt32BE(info.offset);
+  bytesUsed(info,4);
+
+  var message = {
+    targetURI: targetURI,
+    responseURI: responseURI,
+    length: messageLength,
+    // Message payload is just an AMF0 value-type
+    value: readData(buffer, info)
+  }
+
+  return message;
+}
+
+function readData (buffer, info) {
   // read the "type" byte
   var type = buffer.readUInt8(info.offset);
   bytesUsed(info, 1);