Trying to implement byteOffset for read()

src/buffered-reader.js

@@ -13,6 +13,7 @@ var EVENTS = require ("events");
 var FS = require ("fs");
 
 var BUFFER_SIZE = 16384;
+var WIN = process.platform.indexOf ("win") !== -1;
 
 var INVALID_BUFFER_SIZE = "The buffer size must be greater than 0.";
 var INVALID_START_OFFSET = "The start offset must be greater than or equals to 0.";
@@ -64,10 +65,15 @@ BufferedReader.prototype.interrupt = function (){
 	this._interrupted = true;
 };
 
+var realByteLength = function (character, encoding){
+	return Buffer.byteLength (character, encoding);
+};
+
 BufferedReader.prototype.read = function (){
 	var stream = FS.createReadStream (this._fileName, this._settings);
 
 	var lastChunk;
+	var byteOffset = 0;
 	var me = this;
 
 	var onChar = this.listeners ("character").length !== 0;
@@ -80,44 +86,48 @@ BufferedReader.prototype.read = function (){
 		var chunk;
 		var character;
 		var len = data.length;
+		var isCR = false;
 
 		if (loop){
 			for (var i=0; i<len; i++){
 				if (me._interrupted) break;
 
 				character = data[i];
-				if (stream.encoding){
-					if (onChar) me.emit ("character", character === "\r" ? "\n" : character);
-				}else{
+				if (!stream.encoding){
 					if (onByte) me.emit ("byte", character);
 					continue;
 				}
 
-				if (!onLine) continue;
-				if (character === "\n" || character === "\r"){
-					chunk = data.slice (offset, i);
+				byteOffset += realByteLength (character, me._settings.encoding);
+				if (onChar) me.emit ("character", character, byteOffset);
+
+				if (character === "\r"){
+					isCR = true;
+					continue;
+				}
+
+				if (character === "\n"){
+					chunk = data.slice (offset, isCR ? i - 1 : i);
 					offset = i + 1;
 
 					if (lastChunk){
 						chunk = lastChunk.concat (chunk);
 						lastChunk = null;
 					}
 
-					if (i + 1 !== len && character === "\r" && data[i + 1] === "\n"){
-						i++;
-					}
-
-					me.emit ("line", chunk);
+					me.emit ("line", chunk, byteOffset);
 				}
+
+				isCR = false;
 			}
 
-			if (onLine && stream.encoding && offset !== len){
+			if (stream.encoding && offset !== len){
 				var s = offset === 0 ? data : data.slice (offset);
 				lastChunk = lastChunk ? lastChunk.concat (s) : s;
 			}
 		}
 
-		me.emit ("buffer", data);
+		me.emit ("buffer", data, byteOffset);
 		if (me._interrupted){
 			me._interrupted = false;
 			stream.destroy ();
@@ -128,7 +138,7 @@ BufferedReader.prototype.read = function (){
 	stream.on ("end", function (){
 		me._interrupted = false;
 		if (loop && lastChunk){
-			me.emit ("line", lastChunk);
+			me.emit ("line", lastChunk, byteOffset);
 		}
 		me.emit ("end");
 	});

test/a

@@ -0,0 +1,2 @@
+asd
+qwe

test/playground.js

@@ -1 +1,21 @@
-var BufferedReader = require ("../build/buffered-reader");
+var BufferedReader = require ("../src/buffered-reader");
+
+new BufferedReader ("a", { encoding: "utf8" })
+	.on ("error", function (error){
+		console.log (error);
+	})
+	.on ("character", function (c, byteOffset){
+		console.log ("char: >" + c.charCodeAt(0) + "< " + byteOffset);
+	})
+	.on ("line", function (line, byteOffset){
+		console.log ("line: >" + line + "< " + byteOffset);
+	})
+	.on ("buffer", function (buffer, byteOffset){
+		console.log ("buffer: >" + buffer + "< " + byteOffset);
+	})
+	.read ();
+
+//console.log (Buffer.byteLength ("a", "utf8"));	//bytes: 1, UNICODE hex: 0x61 (1), REAL hex: 0x61 (1)
+//console.log (Buffer.byteLength ("¡", "utf8"));	//bytes: 2, UNICODE hex: 0xA1 (1), REAL hex: 0xC2A1 (2)
+//console.log (Buffer.byteLength ("↑", "utf8"));	//bytes: 3, UNICODE hex: 0x2191 (2), REAL hex: 0xE28691 (3)
+//console.log (Buffer.byteLength ("𤁥", "utf8"));	//bytes: 3, UNICODE hex: 0x24065 (3), REAL hex: 0xF0A481A5 (4)