bool Parser::Parse(const std::vector<Token>& inTokens, Node **outParseTree)
{
Node* rootNode = new Node(kNodeType_Root);
unsigned int tokenCount = inTokens.size();
int scopeLevel = 0;
bool inComment = false;
TextureNode* currentTextureNode = nullptr;
OperationNode* currentOperationNode = nullptr;
for(unsigned int index = 0; index < tokenCount; ++index)
{
const Token& currentToken = inTokens[index];
switch(currentToken.GetType())
{
case kToken_ScopeBegin:
{
if( !inComment )
{
// We're opening a new texture scope so it shouldn't be null
assert( currentTextureNode != nullptr );
scopeLevel++;
}
break;
}
case kToken_ScopeEnd:
{
if( !inComment )
{
// We're closing a texture scope so it shouldn't be null
assert( currentTextureNode != nullptr );
scopeLevel--;
rootNode->InsertNode( currentTextureNode );
currentTextureNode = nullptr;
}
break;
}
case kToken_CommentBegin:
{
assert( !inComment );
inComment = true;
break;
}
case kToken_CommentEnd:
{
assert( inComment );
inComment = false;
break;
}
case kToken_Terminator:
{
if( !inComment )
{
// Terminate the operation
assert( currentOperationNode != nullptr );
assert( currentTextureNode != nullptr );
currentTextureNode->InsertNode( currentOperationNode );
currentOperationNode = nullptr;
}
break;
}
case kToken_Identifier:
{
if( !inComment )
{
// Start a new texture if we're not in one
if( currentTextureNode == nullptr )
{
IdentifierTokenData* tokenData = static_cast<IdentifierTokenData*>(currentToken.GetData());
assert( tokenData->GetValue().compare( "Texture" ) == 0 );
// Free the data here. This means the tokens are one time use
delete tokenData;
currentTextureNode = new TextureNode( "Undefined" );
}
else
{
// We're still looking for a name
if( currentTextureNode->GetName().compare( "Undefined") == 0 )
{
IdentifierTokenData* tokenData = static_cast<IdentifierTokenData*>(currentToken.GetData());
// Make sure no one tries to name it "Undefined"
assert( tokenData->GetValue().compare( "Undefined" ) != 0 );
currentTextureNode->SetName( tokenData->GetValue() );
// Free the data here. This means the tokens are one time use
delete tokenData;
// We also need width height and pixel depth
assert( index + 3 < tokenCount );
assert( inTokens[index+1].GetType() == kToken_Number );
assert( inTokens[index+2].GetType() == kToken_Number );
assert( inTokens[index+3].GetType() == kToken_Number );
NumberTokenData* widthData = static_cast<NumberTokenData*>(inTokens[index+1].GetData());
NumberTokenData* heightData = static_cast<NumberTokenData*>(inTokens[index+2].GetData());
NumberTokenData* pixelDepthData = static_cast<NumberTokenData*>(inTokens[index+3].GetData());
currentTextureNode->SetWidth( widthData->GetValue() );
currentTextureNode->SetHeight( heightData->GetValue() );
currentTextureNode->SetPixelDepth( pixelDepthData->GetValue() );
delete widthData;
delete heightData;
delete pixelDepthData;
}
else
{
// We're looking for operations now.
assert( currentOperationNode == nullptr );
IdentifierTokenData* tokenData = static_cast<IdentifierTokenData*>(currentToken.GetData());
currentOperationNode = new OperationNode( tokenData->GetValue() );
// Free the data here. This means the tokens are one time use
delete tokenData;
}
}
}
break;
}
case kToken_Number:
{
if( !inComment )
{
// Add arguments to the operation
if( currentOperationNode != nullptr )
{
NumberTokenData* tokenData = static_cast<NumberTokenData*>(currentToken.GetData());
currentOperationNode->AddArgument( tokenData->GetValue() );
// Free the data here. This means the tokens are one time use
delete tokenData;
}
}
break;
}
case kToken_Undefined:
default:
{
std::cout << "Error! Undefined token encountered!" << std::endl;
delete rootNode;
return false;
}
}
}
*outParseTree = rootNode;
return true;
}
