rtkapi/lib/transform.js

An API to communicate with an R11 server

var Transform   = require("stream").Transform,
    Packet      = require("./packet.js").Packet,
    util        = require("util");


var RTKTransform = function () {
    this._unparsedBuffer = new Buffer(0);
    Transform.call(this, {objectMode: true});
};

util.inherits(RTKTransform, Transform);

//RTKTransform.prototype = new Transform({objectMode: true});

RTKTransform.prototype._transform = function (data, encoding, done) {
    var p, buff;
    if (data instanceof Packet) {
        buff = data.compile();
        this.push(buff);
        done();
    }
    if (data instanceof Buffer) {
        if (this._unparsedBuffer.length > 0) {
            data = Buffer.concat([this._unparsedBuffer, data]);
            this._unparsedBuffer = new Buffer(0);
        }

        var len = Packet.readLength(data);
        if (data.length === len) {
            p = Packet.parse(data);
            this.push(p);
            done();
        } else if (data.length > len) {
            var i = true;
            while (i) {
                p = Packet.parse(data.slice(0, len));
                this.push(p);

                data = data.slice(len);
                len = Packet.readLength(data);
                if (data.length < len) {
                    if (data.length > 0)
                        this._unparsedBuffer = data;
                    i = false;
                    done();
                }
            }
        } else if (data.length < len) {
            this._unparsedBuffer = data;
            done();
        }
    }

    
};

RTKTransform.prototype._flush = function (data, encoding, done) {
    // Make toilet noises
    if (this._unparsedBuffer.length > 0) {
        var len = Packet.readLength(data);
        if (data.length === len) {
            p = Packet.parse(data);
            this.push(p);
            done();
        } else if (data.length > len) {
            var i = true;
            while (i) {
                p = Packet.parse(data.slice(0, len));
                this.push(p);

                data = data.slice(len);
                len = Packet.readLength(data);
                if (data.length < len) {
                    if (data.length > 0)
                        this._unparsedBuffer = data;
                    i = false;
                    done();
                }
            }
        }
    }
};

exports.RTKTransform = RTKTransform;