public void encode(EncoderContext context)
{
//step F
var buffer = new StringBuilder();
while (context.HasMoreCharacters)
{
char c = context.CurrentChar;
encodeChar(c, buffer);
context.Pos++;
int count = buffer.Length;
if (count >= 4)
{
context.writeCodewords(encodeToCodewords(buffer, 0));
buffer.Remove(0, 4);
int newMode = HighLevelEncoder.lookAheadTest(context.Message, context.Pos, EncodingMode);
if (newMode != EncodingMode)
{
// Return to ASCII encodation, which will actually handle latch to new mode
context.signalEncoderChange(Encodation.ASCII);
break;
}
}
}
buffer.Append((char)31); //Unlatch
handleEOD(context, buffer);
}
internal static void writeNextTriplet(EncoderContext context, StringBuilder buffer)
{
context.writeCodewords(encodeToCodewords(buffer, 0));
buffer.Remove(0, 3);
}
/// <summary>
/// Handle "end of data" situations
/// </summary>
/// <param name="context">the encoder context</param>
/// <param name="buffer">the buffer with the remaining encoded characters</param>
private static void handleEOD(EncoderContext context, StringBuilder buffer)
{
try
{
int count = buffer.Length;
if (count == 0)
{
return; //Already finished
}
if (count == 1)
{
//Only an unlatch at the end
context.updateSymbolInfo();
int available = context.SymbolInfo.dataCapacity - context.CodewordCount;
int remaining = context.RemainingCharacters;
// The following two lines are a hack inspired by the 'fix' from https://sourceforge.net/p/barcode4j/svn/221/
if (remaining > available)
{
context.updateSymbolInfo(context.CodewordCount + 1);
available = context.SymbolInfo.dataCapacity - context.CodewordCount;
}
if (remaining <= available && available <= 2)
{
return; //No unlatch
}
}
if (count > 4)
{
throw new InvalidOperationException("Count must not exceed 4");
}
int restChars = count - 1;
String encoded = encodeToCodewords(buffer, 0);
bool endOfSymbolReached = !context.HasMoreCharacters;
bool restInAscii = endOfSymbolReached && restChars <= 2;
if (restChars <= 2)
{
context.updateSymbolInfo(context.CodewordCount + restChars);
int available = context.SymbolInfo.dataCapacity - context.CodewordCount;
if (available >= 3)
{
restInAscii = false;
context.updateSymbolInfo(context.CodewordCount + encoded.Length);
//available = context.symbolInfo.dataCapacity - context.getCodewordCount();
}
}
if (restInAscii)
{
context.resetSymbolInfo();
context.Pos -= restChars;
}
else
{
context.writeCodewords(encoded);
}
}
finally
{
context.signalEncoderChange(Encodation.ASCII);
}
}