iTextSharp.text.pdf.BarcodeDatamatrix.EdifactEncodation C# (CSharp) Метод

        private static int EdifactEncodation(byte[] text, int textOffset, int textLength, byte[] data, int dataOffset, int dataLength) {
            int ptrIn, ptrOut, edi, pedi, c;
            if (textLength == 0)
                return 0;
            ptrIn = 0;
            ptrOut = 0;
            edi = 0;
            pedi = 18;
            bool ascii = true;
            for (; ptrIn < textLength; ++ptrIn) {
                c = text[ptrIn + textOffset] & 0xff;
                if (((c & 0xe0) == 0x40 || (c & 0xe0) == 0x20) && c != '_') {
                    if (ascii) {
                        if (ptrOut + 1 > dataLength)
                            break;
                        data[dataOffset + ptrOut++] = (byte)240;
                        ascii = false;
                    }
                    c &= 0x3f;
                    edi |= c << pedi;
                    if (pedi == 0) {
                        if (ptrOut + 3 > dataLength)
                            break;
                        data[dataOffset + ptrOut++] = (byte)(edi >> 16);
                        data[dataOffset + ptrOut++] = (byte)(edi >> 8);
                        data[dataOffset + ptrOut++] = (byte)edi;
                        edi = 0;
                        pedi = 18;
                    }
                    else
                        pedi -= 6;
                }
                else {
                    if (!ascii) {
                        edi |= ('_' & 0x3f) << pedi;
                        if (ptrOut + (3 - pedi / 8) > dataLength)
                            break;
                        data[dataOffset + ptrOut++] = (byte)(edi >> 16);
                        if (pedi <= 12)
                            data[dataOffset + ptrOut++] = (byte)(edi >> 8);
                        if (pedi <= 6)
                            data[dataOffset + ptrOut++] = (byte)edi;
                        ascii = true;
                        pedi = 18;
                        edi = 0;
                    }
                    if (c > 127) {
                        if (ptrOut >= dataLength)
                            break;
                        data[dataOffset + ptrOut++] = (byte)235;
                        c -= 128;
                    }
                    if (ptrOut >= dataLength)
                        break;
                    data[dataOffset + ptrOut++] = (byte)(c + 1);
                }
            }
            if (ptrIn != textLength)
                return -1;
            if (!ascii) {
                edi |= ('_' & 0x3f) << pedi;
                if (ptrOut + (3 - pedi / 8) > dataLength)
                    return -1;
                data[dataOffset + ptrOut++] = (byte)(edi >> 16);
                if (pedi <= 12)
                    data[dataOffset + ptrOut++] = (byte)(edi >> 8);
                if (pedi <= 6)
                    data[dataOffset + ptrOut++] = (byte)edi;
            }
            return ptrOut;
        }