Add support for byte strings as object key index

Closes #2.
Chocobo1 · Sep 30, 2020 · c33a02f · c33a02f
1 parent a2b4543
commit c33a02f
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Showing 4 changed files with 127 additions and 28 deletions.
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "bencode_online",
-  "version": "1.0.0",
+  "version": "2.0.0",
   "description": "Bencode & bdecode in your browser",
   "repository": {
     "type": "git",

diff --git a/src/bencode/decode.js b/src/bencode/decode.js
@@ -121,10 +121,10 @@ decode.find = function (chr) {
 decode.dictionary = function () {
   decode.position++
 
-  var dict = {}
+  var dict = new Map()
 
   while (decode.data[decode.position] !== END_OF_TYPE) {
-    dict[decode.buffer()] = decode.next()
+    dict.set(decode.buffer(), decode.next())
   }
 
   decode.position++

diff --git a/src/bencode/encode.js b/src/bencode/encode.js
@@ -32,6 +32,7 @@ encode.getType = function (value) {
   if (value instanceof Number) return 'number'
   if (value instanceof Boolean) return 'boolean'
   if (value instanceof ArrayBuffer) return 'arraybuffer'
+  if (value instanceof Map) return 'map'
   return typeof value
 }
 
@@ -47,6 +48,7 @@ encode._encode = function (buffers, data) {
     case 'boolean': encode.number(buffers, data); break
     case 'arraybufferview': encode.buffer(buffers, Buffer.from(data.buffer, data.byteOffset, data.byteLength)); break
     case 'arraybuffer': encode.buffer(buffers, Buffer.from(data)); break
+    case 'map': encode._map(buffers, data); break
   }
 }
 
@@ -99,6 +101,24 @@ encode.dict = function (buffers, data) {
   buffers.push(buffE)
 }
 
+encode._map = function (buffers, data) {
+  buffers.push(buffD)
+
+  // fix for issue #13 - sorted dicts
+  const keys = []
+  let iter = data.keys();
+  while (key = iter.next().value)
+    keys.push(key)
+  keys.sort(Buffer.compare)
+
+  for (const key of keys) {
+    encode.buffer(buffers, key)
+    encode._encode(buffers, data.get(key))
+  }
+
+  buffers.push(buffE)
+}
+
 encode.list = function (buffers, data) {
   var i = 0
   var c = data.length

diff --git a/src/main.ts b/src/main.ts
@@ -21,7 +21,7 @@ function loadFile(blob: Blob): Promise<ArrayBuffer>
   });
 }
 
-function decodeString(data: ArrayBuffer): string
+function tryEncodeHexstring(data: ArrayBuffer): string
 {
   const isStringValid = (str: string): boolean =>
   {
@@ -50,34 +50,71 @@ function decodeString(data: ArrayBuffer): string
   return bufferToHexstring(Buffer.from(data));
 }
 
-function bytearrayToString(obj: Record<string, any>): object
+function encodeToArray(data: Array<any>): Array<any>
 {
-  // traverse through obj
-  for (const key in obj)
+  const ret = [];
+
+  for (const val of data)
   {
-    const val = obj[key];
+    if (typeof val === "number")
+    {
+      ret.push(val);
+    }
+    else if (val instanceof Uint8Array)
+    {
+      ret.push(tryEncodeHexstring(val));
+    }
+    else if (val instanceof Array)
+    {
+      ret.push(encodeToArray(val));
+    }
+    else if (val instanceof Map)
+    {
+      ret.push(encodeToObject(val));
+    }
+    else
+    {
+      //throw new Error("Type unhandled: " + typeof val + "\nValue: " + val);
+    }
+  }
+
+  return ret;
+}
+
+function encodeToObject(data: Map<Buffer, any>): Record<string, any>
+{
+  const ret: Record<string, any> = {};
+
+  for (const [key, val] of data)
+  {
+    const keyString = tryEncodeHexstring(key);
 
-    if (val instanceof Number)
+    if (typeof val === "number")
     {
+      ret[keyString] = val;
     }
     else if (val instanceof Uint8Array)
     {
-      obj[key] = decodeString(val);
+      ret[keyString] = tryEncodeHexstring(val);
     }
     else if (val instanceof Array)
     {
-      bytearrayToString(val);
+      ret[keyString] = encodeToArray(val);
     }
-    else if (val instanceof Object)
+    else if (val instanceof Map)
+    {
+      ret[keyString] = encodeToObject(val);
+    }
+    else
     {
-      bytearrayToString(val);
+      //throw new Error("Type unhandled: " + typeof val + "\nValue: " + val);
     }
   }
 
-  return obj;
+  return ret;
 }
 
-function stringToBytearray(obj: Record<string, any>): object
+function tryDecodeHexstring(str: string): Buffer
 {
   const isHexArray = (str: string): boolean =>
   {
@@ -91,31 +128,73 @@ function stringToBytearray(obj: Record<string, any>): object
     return Buffer.from(str, 'hex');
   }
 
-  for (const key in obj)
+  return isHexArray(str)
+    ? hexstringToBuffer(str)
+    : Buffer.from(str);
+}
+
+function decodeToArray(data: Array<any>): Array<any>
+{
+  const ret = [];
+
+  for (const val of data)
+  {
+    if (typeof val === "number")
+    {
+      ret.push(val);
+    }
+    else if (isString(val))
+    {
+      ret.push(tryDecodeHexstring(val));
+    }
+    else if (val instanceof Array)
+    {
+      ret.push(decodeToArray(val));
+    }
+    else if (val instanceof Object)
+    {
+      ret.push(decodeToMap(val));
+    }
+    else
+    {
+      //throw new Error("Type unhandled: " + typeof val + "\nValue: " + val);
+    }
+  }
+
+  return ret;
+}
+
+function decodeToMap(data: Record<string, any>): Map<Buffer, any>
+{
+  const ret = new Map();
+
+  for (const [key, val] of Object.entries(data))
   {
-    const val = obj[key];
+    const keyString = tryDecodeHexstring(key);
 
-    if (val instanceof Number)
+    if (typeof val === "number")
     {
+      ret.set(keyString, val);
     }
     else if (isString(val))
     {
-      if (isHexArray(val))
-        obj[key] = hexstringToBuffer(val);
-      else
-        obj[key] = Buffer.from(val);
+      ret.set(keyString, tryDecodeHexstring(val));
     }
     else if (val instanceof Array)
     {
-      stringToBytearray(val);
+      ret.set(keyString, decodeToArray(val));
     }
     else if (val instanceof Object)
     {
-      stringToBytearray(val);
+      ret.set(keyString, decodeToMap(val));
+    }
+    else
+    {
+      //throw new Error("Type unhandled: " + typeof val + "\nValue: " + val);
     }
   }
 
-  return obj;
+  return ret;
 }
 
 /// End of helper functions
@@ -135,7 +214,7 @@ function main(): void
 
   const loadData = (fileName: string, data: Buffer): void =>
   {
-    let decoded = "";
+    let decoded;
     try
     {
       decoded = bencode.decode(data);
@@ -148,7 +227,7 @@ function main(): void
       return;
     }
 
-    const result = bytearrayToString(Object.assign({}, decoded));
+    const result = encodeToObject(decoded);
     editor.setValue(JSON.stringify(result, null, 3) + "\n");
     editor.gotoLine(0, 0, undefined!);
     editor.scrollToLine(0, undefined!, undefined!, undefined!);
@@ -194,7 +273,7 @@ function main(): void
     try
     {
       const obj = JSON.parse(text);
-      const obj2 = stringToBytearray(obj);
+      const obj2 = decodeToMap(obj);
       data = bencode.encode(obj2);
     }
     catch(e)