public int HandleMatch(IProcessorState processor, int bufferLength, ref int currentBufferPosition, int token, Stream target)
{
bool flag;
if (processor.Config.Flags.TryGetValue(OperationName, out flag) && !flag)
{
target.Write(Tokens[token].Value, Tokens[token].Start, Tokens[token].Length);
return(Tokens[token].Length);
}
// conditional has not started, or this is the "if"
if (_current != null || IsTokenIndexOfType(token, IfTokenBaseIndex) || IsTokenIndexOfType(token, IfTokenActionableBaseIndex))
{
if (_definition._wholeLine)
{
processor.SeekBackUntil(processor.EncodingConfig.LineEndings);
}
else if (_definition._trimWhitespace)
{
processor.TrimWhitespace(false, true, ref bufferLength, ref currentBufferPosition);
}
}
BEGIN:
//Got the "if" token...
if (IsTokenIndexOfType(token, IfTokenBaseIndex) || IsTokenIndexOfType(token, IfTokenActionableBaseIndex))
{
if (_current == null)
{
_current = new EvaluationState(this);
}
else
{
_pendingCompletion.Push(_current);
_current = new EvaluationState(this);
}
//If the "if" branch is taken, all else and elseif blocks will be omitted, return
// control to the processor so nested "if"s/mutations can be processed. Note that
// this block will not be terminated until the corresponding endif is found
if (_current.Evaluate(processor, ref bufferLength, ref currentBufferPosition))
{
if (_definition.WholeLine)
{
processor.SeekForwardThrough(processor.EncodingConfig.LineEndings, ref bufferLength, ref currentBufferPosition);
}
if (IsTokenIndexOfType(token, IfTokenActionableBaseIndex))
{
// "Actionable" if token, so enable the flag operation(s)
_current.ToggleActionableOperations(true, processor);
}
// if (true_condition) was found.
return(0);
}
else
{
// if (false_condition) was found. Skip to the next token of the if-elseif-elseif-...elseif-else-endif
SeekToNextTokenAtSameLevel(processor, ref bufferLength, ref currentBufferPosition, out token);
goto BEGIN;
}
}
// If we've got an unbalanced statement, emit the token
if (_current == null)
{
target.Write(Tokens[token].Value, Tokens[token].Start, Tokens[token].Length);
return(Tokens[token].Length);
}
//Got the endif token, exit to the parent "if" scope if it exists
if (IsTokenIndexOfType(token, EndTokenBaseIndex))
{
if (_pendingCompletion.Count > 0)
{
_current = _pendingCompletion.Pop();
_current.ToggleActionableOperations(_current.ActionableOperationsEnabled, processor);
}
else
{
// disable the special case operations (note: they may already be disabled, but cheaper to do than check)
_current.ToggleActionableOperations(false, processor);
_current = null;
}
if (_definition._wholeLine)
{
processor.SeekForwardThrough(processor.EncodingConfig.LineEndings, ref bufferLength, ref currentBufferPosition);
}
else if (_definition._trimWhitespace)
{
processor.TrimWhitespace(true, false, ref bufferLength, ref currentBufferPosition);
}
return(0);
}
if (_current.BranchTaken)
{
processor.SeekBackUntil(processor.EncodingConfig.LineEndings, true);
//A previous branch was taken. Skip to the endif token.
// NOTE: this can probably use the new method SeekToNextTokenAtSameLevel() - they do almost the same thing.
SkipToMatchingEndif(processor, ref bufferLength, ref currentBufferPosition, ref token);
if (_pendingCompletion.Count > 0)
{
_current = _pendingCompletion.Pop();
_current.ToggleActionableOperations(_current.ActionableOperationsEnabled, processor);
}
else
{
// disable the special case operation (note: it may already be disabled, but cheaper to do than check)
_current.ToggleActionableOperations(false, processor);
_current = null;
}
if (_definition._wholeLine)
{
processor.SeekForwardUntil(processor.EncodingConfig.LineEndings, ref bufferLength, ref currentBufferPosition);
}
else if (_definition._trimWhitespace)
{
processor.TrimWhitespace(true, false, ref bufferLength, ref currentBufferPosition);
}
return(0);
}
//We have an "elseif" and haven't taken a previous branch
if (IsTokenIndexOfType(token, ElseIfTokenBaseIndex) || IsTokenIndexOfType(token, ElseIfTokenActionableBaseIndex))
{
// 8-19 attempt to make the same as if() handling
//
if (_current.Evaluate(processor, ref bufferLength, ref currentBufferPosition))
{
if (_definition.WholeLine)
{
processor.SeekForwardThrough(processor.EncodingConfig.LineEndings, ref bufferLength, ref currentBufferPosition);
}
if (IsTokenIndexOfType(token, ElseIfTokenActionableBaseIndex))
{
// the elseif branch is taken.
_current.ToggleActionableOperations(true, processor);
}
return(0);
}
else
{
SeekToNextTokenAtSameLevel(processor, ref bufferLength, ref currentBufferPosition, out token);
// In the original version this was conditional on SeekToToken() succeeding.
// Not sure if it should be conditional. It should never fail, unless the template is malformed.
goto BEGIN;
}
}
//We have an "else" token and haven't taken any other branches, return control
// after setting that a branch has been taken
if (IsTokenIndexOfType(token, ElseTokenBaseIndex) || IsTokenIndexOfType(token, ElseTokenActionableBaseIndex))
{
if (IsTokenIndexOfType(token, ElseTokenActionableBaseIndex))
{
_current.ToggleActionableOperations(true, processor);
}
_current.BranchTaken = true;
processor.WhitespaceHandler(ref bufferLength, ref currentBufferPosition, wholeLine: _definition._wholeLine, trim: _definition._trimWhitespace);
return(0);
}
else
{
Debug.Assert(true, "Unknown token index: " + token);
return(0); // TODO: revisit. Not sure what's best here.
}
}
