/*************************************************************************/
/*  shader_language.cpp                                                  */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "shader_language.h"
#include "print_string.h"
#include "os/os.h"
static bool _is_text_char(CharType c) {

	return (c>='a' && c<='z') || (c>='A' && c<='Z') || (c>='0' && c<='9') || c=='_';
}

static bool _is_number(CharType c) {

	return (c>='0' && c<='9');
}

static bool _is_hex(CharType c) {

	return (c>='0' && c<='9') || (c>='a' && c<='f') || (c>='A' && c<='F');
}

const char * ShaderLanguage::token_names[TK_MAX]={
	"EMPTY",
	"INDENTIFIER",
	"TRUE",
	"FALSE",
	"REAL_CONSTANT",
	"TYPE_VOID",
	"TYPE_BOOL",
	"TYPE_FLOAT",
	"TYPE_VEC2",
	"TYPE_VEC3",
	"TYPE_VEC4",
	"TYPE_MAT3",
	"TYPE_MAT4",
	"TYPE_TEXTURE",
	"TYPE_CUBEMAP",
	"TYPE_COLOR",
	"OP_EQUAL",
	"OP_NOT_EQUAL",
	"OP_LESS",
	"OP_LESS_EQUAL",
	"OP_GREATER",
	"OP_GREATER_EQUAL",
	"OP_AND",
	"OP_OR",
	"OP_NOT",
	"OP_ADD",
	"OP_SUB",
	"OP_MUL",
	"OP_DIV",
	"OP_NEG",
	"OP_ASSIGN",
	"OP_ASSIGN_ADD",
	"OP_ASSIGN_SUB",
	"OP_ASSIGN_MUL",
	"OP_ASSIGN_DIV",
	"CF_IF",
	"CF_ELSE",
	"CF_RETURN",
	"BRACKET_OPEN",
	"BRACKET_CLOSE",
	"CURLY_BRACKET_OPEN",
	"CURLY_BRACKET_CLOSE",
	"PARENTHESIS_OPEN",
	"PARENTHESIS_CLOSE",
	"COMMA",
	"SEMICOLON",
	"PERIOD",
	"UNIFORM",
	"ERROR",
};

ShaderLanguage::Token ShaderLanguage::read_token(const CharType* p_text,int p_len,int &r_line,int &r_chars) {

#define GETCHAR(m_idx) ((m_idx<p_len)?p_text[m_idx]:CharType(0))

	r_chars=1; //by default everything eats one char
	switch(GETCHAR(0)) {

		case '\t':
		case '\r':
		case ' ':
			return Token();
		case '\n':
			r_line++;
			return Token();
		case '/': {

			switch(GETCHAR(1)) {
				case '*': { // block comment


					while(true) {
						if (GETCHAR(r_chars+1)=='0')
							break;
						if (GETCHAR(r_chars+1)=='*' && GETCHAR(r_chars+2)=='/')
							break;
						if (GETCHAR(r_chars+1)=='\n')
							r_line++;
							r_chars++;
					}

					return Token();

				} break;
				case '/': { // line comment skip

					while(GETCHAR(r_chars+1)!='\n' && GETCHAR(r_chars+1)!=0) {
							r_chars++;
					}

					return Token();

				} break;
				case '=': { // diveq

					r_chars=2;
					return Token(TK_OP_ASSIGN_DIV);

				} break;
				default:
					return Token(TK_OP_DIV);

			}
		} break;
		case '=': {
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_EQUAL);
			}

			return Token(TK_OP_ASSIGN);

		} break;
		case '<': {
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_LESS_EQUAL);
			} /*else if (GETCHAR(1)=='<') {
				r_chars++;
				if (GETCHAR(2)=='=') {
					r_chars++;
					return Token(TK_OP_ASSIGN_SHIFT_LEFT);
				}

				return Token(TK_OP_SHIFT_LEFT);
			}*/

			return Token(TK_OP_LESS);

		} break;
		case '>': {
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_GREATER_EQUAL);
			}/* else if (GETCHAR(1)=='<') {
				r_chars++;
				if (GETCHAR(2)=='=') {
					r_chars++;
					return Token(TK_OP_ASSIGN_SHIFT_RIGHT);
				}

				return Token(TK_OP_SHIFT_RIGHT);
			}*/

			return Token(TK_OP_GREATER);

		} break;
		case '!': {
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_NOT_EQUAL);
			}

			return Token(TK_OP_NOT);

		} break;
		//case '"' //string - no strings in shader
		//case '\'' //string - no strings in shader
		case '{':
			return Token(TK_CURLY_BRACKET_OPEN);
		case '}':
			return Token(TK_CURLY_BRACKET_CLOSE);
		//case '[':
		//	return Token(TK_BRACKET_OPEN);
		//case ']':
	//		return Token(TK_BRACKET_CLOSE);
		case '(':
			return Token(TK_PARENTHESIS_OPEN);
		case ')':
			return Token(TK_PARENTHESIS_CLOSE);
		case ',':
			return Token(TK_COMMA);
		case ';':
			return Token(TK_SEMICOLON);
		//case '?':
		//	return Token(TK_QUESTION_MARK);
		//case ':':
		//	return Token(TK_COLON); //for methods maybe but now useless.
		//case '^':
		//	return Token(TK_OP_BIT_XOR);
		//case '~':
	//		return Token(TK_OP_BIT_INVERT);
		case '&': {

			if (GETCHAR(1)=='&') {

				r_chars++;
				return Token(TK_OP_AND);
			}

			return Token(TK_ERROR,"Unknown character");

/*
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_BIT_AND);
			} else if (GETCHAR(1)=='&') {
				r_chars++;
				return Token(TK_OP_AND);
			}
			return TK_OP_BIT_AND;*/
		} break;
		case '|': {

			if (GETCHAR(1)=='|') {

				r_chars++;
				return Token(TK_OP_OR);
			}

			return Token(TK_ERROR,"Unknown character");

			/*
			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_BIT_OR);
			} else if (GETCHAR(1)=='|') {
				r_chars++;
				return Token(TK_OP_OR);
			}
			return TK_OP_BIT_OR;
			*/
		} break;
		case '*': {

			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_MUL);
			}
			return TK_OP_MUL;
		} break;
		case '+': {

			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_ADD);
			}  /*else if (GETCHAR(1)=='+') {

				r_chars++;
				return Token(TK_OP_PLUS_PLUS);
			}*/

			return TK_OP_ADD;
		} break;
		case '-': {

			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_SUB);
			}/* else if (GETCHAR(1)=='-') {

				r_chars++;
				return Token(TK_OP_MINUS_MINUS);
			}*/

			return TK_OP_SUB;
		} break;
		/*case '%': {

			if (GETCHAR(1)=='=') {
				r_chars++;
				return Token(TK_OP_ASSIGN_MOD);
			}

			return TK_OP_MOD;
		} break;*/
		default: {

			if (_is_number(GETCHAR(0)) || (GETCHAR(0)=='.' && _is_number(GETCHAR(1)))) {
				// parse number
				bool period_found=false;
				bool exponent_found=false;
				bool hexa_found=false;
				bool sign_found=false;

				String str;
				int i=0;

				while(true) {
					if (GETCHAR(i)=='.') {
						if (period_found || exponent_found)
							return Token(TK_ERROR,"Invalid numeric constant");
						period_found=true;
					} else if (GETCHAR(i)=='x') {
						if (hexa_found || str.length()!=1 || str[0]!='0')
							return Token(TK_ERROR,"Invalid numeric constant");
						hexa_found=true;
					} else if (GETCHAR(i)=='e') {
						if (hexa_found || exponent_found)
							return Token(TK_ERROR,"Invalid numeric constant");
						exponent_found=true;
					} else if (_is_number(GETCHAR(i))) {
						//all ok
					} else if (hexa_found && _is_hex(GETCHAR(i))) {

					} else if ((GETCHAR(i)=='-' || GETCHAR(i)=='+') && exponent_found) {
						if (sign_found)
							return Token(TK_ERROR,"Invalid numeric constant");
						sign_found=true;
					} else
						break;

					str+=CharType(GETCHAR(i));
					i++;
				}

				if (!_is_number(str[str.length()-1]))
					return Token(TK_ERROR,"Invalid numeric constant");

				r_chars+=str.length()-1;
				return Token(TK_REAL_CONSTANT,str);
				/*
				if (period_found)
					return Token(TK_NUMBER_REAL,str);
				else
					return Token(TK_NUMBER_INTEGER,str);*/

			}

			if (GETCHAR(0)=='.') {
				//parse period
				return Token(TK_PERIOD);
			}

			if (_is_text_char(GETCHAR(0))) {
				// parse identifier
				String str;
				str+=CharType(GETCHAR(0));

				while(_is_text_char(GETCHAR(r_chars))) {

					str+=CharType(GETCHAR(r_chars));
					r_chars++;
				}

				//see if keyword
				struct _kws { TokenType token; const char *text;};
				static const  _kws keyword_list[]={
					{TK_TRUE,"true"},
					{TK_FALSE,"false"},
					{TK_TYPE_VOID,"void"},
					{TK_TYPE_BOOL,"bool"},
					/*{TK_TYPE_INT,"int"},
					{TK_TYPE_INT2,"int2"},
					{TK_TYPE_INT3,"int3"},
					{TK_TYPE_INT4,"int4"},*/
					{TK_TYPE_FLOAT,"float"},
					/*{TK_TYPE_FLOAT2,"float2"},
					{TK_TYPE_FLOAT3,"float3"},
					{TK_TYPE_FLOAT4,"float4"},*/
					{TK_TYPE_VEC2,"vec2"},
					{TK_TYPE_VEC3,"vec3"},
					{TK_TYPE_VEC4,"vec4"},
					{TK_TYPE_TEXTURE,"texture"},
					{TK_TYPE_CUBEMAP,"cubemap"},
					{TK_TYPE_COLOR,"color"},
					/*
					{TK_TYPE_MAT2,"mat2"},
					{TK_TYPE_MAT3,"mat3"},
					{TK_TYPE_MAT4,"mat3"},*/
					{TK_TYPE_MAT3,"mat3"},
					{TK_TYPE_MAT4,"mat4"},
					{TK_CF_IF,"if"},
					{TK_CF_ELSE,"else"},
					/*
					{TK_CF_FOR,"for"},
					{TK_CF_WHILE,"while"},
					{TK_CF_DO,"do"},
					{TK_CF_SWITCH,"switch"},
					{TK_CF_BREAK,"break"},
					{TK_CF_CONTINUE,"continue"},*/
					{TK_CF_RETURN,"return"},
					{TK_UNIFORM,"uniform"},
					{TK_ERROR,NULL}
				};

				int idx=0;

				while(keyword_list[idx].text) {

					if (str==keyword_list[idx].text)
						return Token(keyword_list[idx].token);
					idx++;
				}


				return Token(TK_INDENTIFIER,str);
			}

			return Token(TK_ERROR,"Unknown character");

		} break;
	}

	ERR_PRINT("BUG");
	return Token();
}

Error ShaderLanguage::tokenize(const String& p_text,Vector<Token> *p_tokens,String *r_error,int *r_err_line,int *r_err_column) {


	int len =p_text.length();
	int pos=0;

	int line=0;

	while(pos<len) {

		int advance=0;
		int prev_line=line;
		Token t = read_token(&p_text[pos],len-pos,line,advance);
		t.line=prev_line;

		if (t.type==TK_ERROR) {

			if (r_error) {
				return ERR_COMPILATION_FAILED;
				*r_error=t.text;
				*r_err_line=line;
			}
		}

		if (t.type!=TK_EMPTY)
			p_tokens->push_back(t);
		//if (prev_line!=line)
		//	p_tokens->push_back(Token(TK_LINE,itos(line)));

		pos+=advance;

	}

	return OK;

}

String ShaderLanguage::lex_debug(const String& p_code) {

	Vector<Token> tokens;
	String error;
	int errline,errcol;
	if (tokenize(p_code,&tokens,&error,&errline,&errcol)!=OK)
		return error;
	String ret;
	for(int i=0;i<tokens.size();i++) {
		ret+=String(token_names[tokens[i].type])+":"+itos(tokens[i].line)+":"+itos(tokens[i].col)+":"+tokens[i].text+"\n";
	}

	return ret;

}

bool ShaderLanguage::is_token_datatype(TokenType p_type) {

	return
	(p_type==TK_TYPE_VOID) ||
	(p_type==TK_TYPE_BOOL) ||
	(p_type==TK_TYPE_FLOAT) ||
	(p_type==TK_TYPE_VEC2) ||
	(p_type==TK_TYPE_VEC3) ||
	(p_type==TK_TYPE_VEC4) ||
	(p_type==TK_TYPE_COLOR) ||
	(p_type==TK_TYPE_MAT3) ||
	(p_type==TK_TYPE_MAT4) ||
	(p_type==TK_TYPE_CUBEMAP) ||
	(p_type==TK_TYPE_TEXTURE);

}

ShaderLanguage::DataType ShaderLanguage::get_token_datatype(TokenType p_type) {

	switch(p_type) {

		case TK_TYPE_VOID: return TYPE_VOID;
		case TK_TYPE_BOOL: return TYPE_BOOL;
		case TK_TYPE_FLOAT: return TYPE_FLOAT;
		case TK_TYPE_VEC2: return TYPE_VEC2;
		case TK_TYPE_VEC3: return TYPE_VEC3;
		case TK_TYPE_VEC4: return TYPE_VEC4;
		case TK_TYPE_COLOR: return TYPE_VEC4;
		case TK_TYPE_MAT3: return TYPE_MAT3;
		case TK_TYPE_MAT4: return TYPE_MAT4;
		case TK_TYPE_TEXTURE: return TYPE_TEXTURE;
		case TK_TYPE_CUBEMAP: return TYPE_CUBEMAP;
		default: return TYPE_VOID;
	}

	return TYPE_VOID;
}


String ShaderLanguage::get_datatype_name(DataType p_type) {

	switch(p_type) {

		case TYPE_VOID: return "void";
		case TYPE_BOOL: return "bool";
		case TYPE_FLOAT: return "float";
		case TYPE_VEC2: return "vec2";
		case TYPE_VEC3: return "vec3";
		case TYPE_VEC4: return "vec4";
		case TYPE_MAT3: return "mat3";
		case TYPE_MAT4: return "mat4";
		case TYPE_TEXTURE: return "texture";
		case TYPE_CUBEMAP: return "cubemap";
		default: return "";
	}

	return "";
}


bool ShaderLanguage::is_token_nonvoid_datatype(TokenType p_type) {

	return
		(p_type==TK_TYPE_BOOL) ||
		(p_type==TK_TYPE_FLOAT) ||
		(p_type==TK_TYPE_VEC2) ||
		(p_type==TK_TYPE_VEC3) ||
		(p_type==TK_TYPE_VEC4) ||
		(p_type==TK_TYPE_COLOR) ||
		(p_type==TK_TYPE_MAT3) ||
		(p_type==TK_TYPE_MAT4) ||
		(p_type==TK_TYPE_TEXTURE) ||
		(p_type==TK_TYPE_CUBEMAP);

}


bool ShaderLanguage::parser_is_at_function(Parser& parser) {

	return (is_token_datatype(parser.get_token_type(0)) && parser.get_token_type(1)==TK_INDENTIFIER && parser.get_token_type(2)==TK_PARENTHESIS_OPEN);
}



bool ShaderLanguage::test_existing_identifier(Node *p_node,const StringName p_identifier,bool p_func,bool p_var,bool p_builtin) {

	Node *node = p_node;

	while(node) {

		if (node->type==Node::TYPE_BLOCK) {

			BlockNode *block = (BlockNode*)node;
			if (block->variables.has(p_identifier))
				return true;
		} else if (node->type==Node::TYPE_PROGRAM) {

			ProgramNode *program = (ProgramNode*)node;			
			for(int i=0;i<program->functions.size();i++) {

				if (program->functions[i].name==p_identifier) {
					return true;
				}
			}

			if(program->builtin_variables.has(p_identifier)) {
				return true;
			}
			if(program->uniforms.has(p_identifier)) {
				return true;
			}

		} else if (node->type==Node::TYPE_FUNCTION) {

			FunctionNode *func=(FunctionNode*)node;
			for(int i=0;i<func->arguments.size();i++)
				if (func->arguments[i].name==p_identifier)
					return true;
		}

		node=node->parent;
	}

	// try keywords

	int idx=0;

	//todo optimize
	while(intrinsic_func_defs[idx].name) {

		if (p_identifier.operator String()==intrinsic_func_defs[idx].name)
			return true;
		idx++;
	}


	return false;

}


Error ShaderLanguage::parse_function(Parser& parser,BlockNode *p_block) {

	if (!p_block->parent || p_block->parent->type!=Node::TYPE_PROGRAM) {
		parser.set_error("Misplaced function");
		return ERR_PARSE_ERROR;

	}


	ProgramNode *program = (ProgramNode*)p_block->parent;

	StringName name = parser.get_token(1).text;

	if (test_existing_identifier(p_block,name)) {

		parser.set_error("Duplicate Identifier (existing variable/builtin/function): "+name);
		return ERR_PARSE_ERROR;

	}


	FunctionNode *function = parser.create_node<FunctionNode>(program);
	function->body = parser.create_node<BlockNode>(function);

	function->name=name;

	function->return_type=get_token_datatype(parser.get_token_type(0));

	{ //add to programnode
		ProgramNode::Function f;
		f.name=name;
		f.function=function;
		program->functions.push_back(f);
	}

	int ofs=3;

	while(true) {

		//end of arguments
		if (parser.get_token_type(ofs)==TK_PARENTHESIS_CLOSE) {
			ofs++;
			break;
		}
		//next argument awaits
		if (parser.get_token_type(ofs)==TK_COMMA) {
			if (!is_token_nonvoid_datatype(parser.get_token_type(ofs+1))) {
				parser.set_error("Expected Identifier or ')' following ','");
				return ERR_PARSE_ERROR;
			}
			ofs++;
			continue;
		}



		if (!is_token_nonvoid_datatype(parser.get_token_type(ofs+0))) {
			parser.set_error("Invalid Argument Type");
			return ERR_PARSE_ERROR;
		}

		DataType identtype=get_token_datatype(parser.get_token_type(ofs+0));

		if (parser.get_token_type(ofs+1)!=TK_INDENTIFIER) {
			parser.set_error("Expected Argument Identifier");
			return ERR_PARSE_ERROR;
		}

		StringName identname=parser.get_token(ofs+1).text;

		if (test_existing_identifier(function,identname)) {
			parser.set_error("Duplicate Argument Identifier: "+identname);
			return ERR_DUPLICATE_SYMBOL;
		}

		FunctionNode::Argument arg;
		arg.name=identname;
		arg.type=identtype;
		//function->body->variables[arg.name]=arg.type;
		function->arguments.push_back(arg);

		ofs+=2;
	}

	parser.advance(ofs);
	// match {
	if (parser.get_token_type()!=TK_CURLY_BRACKET_OPEN) {
		parser.set_error("Expected '{'");
		return ERR_PARSE_ERROR;
	}

	parser.advance();
	Error err = parse_block(parser,function->body);

	if (err)
		return err;

	// make sure that if the function has a return type, it does return something..
	if (function->return_type!=TYPE_VOID) {
		bool found=false;
		for(int i=0;i<function->body->statements.size();i++) {
			if (function->body->statements[i]->type==Node::TYPE_CONTROL_FLOW) {

				ControlFlowNode *cf = (ControlFlowNode*)function->body->statements[i];
				if (cf->flow_op==FLOW_OP_RETURN) {
					// type of return was already checked when inserted
					// no need to check here
					found=true;
				}
			}
		}

		if (!found) {
			parser.set_error("Function must return a value (use the main block)");
			return ERR_PARSE_ERROR;
		}
	}

	return OK;
}


const ShaderLanguage::IntrinsicFuncDef ShaderLanguage::intrinsic_func_defs[]={
	//constructors
	{"bool",TYPE_BOOL,{TYPE_BOOL,TYPE_VOID}},
	{"float",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"vec2",TYPE_VEC2,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"vec3",TYPE_VEC3,{TYPE_FLOAT,TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"vec3",TYPE_VEC3,{TYPE_VEC2,TYPE_FLOAT,TYPE_VOID}},
	{"vec3",TYPE_VEC3,{TYPE_FLOAT,TYPE_VEC2,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_FLOAT,TYPE_FLOAT,TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_FLOAT,TYPE_VEC2,TYPE_FLOAT,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_VEC2,TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VEC2,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_FLOAT,TYPE_VEC3,TYPE_VOID}},
	{"vec4",TYPE_VEC4,{TYPE_VEC3,TYPE_FLOAT,TYPE_VOID}},
	{"mat3",TYPE_MAT3,{TYPE_VEC3,TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"mat4",TYPE_MAT4,{TYPE_VEC4,TYPE_VEC4,TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	//intrinsics - trigonometry
	{"sin",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"cos",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"tan",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"asin",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"acos",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"atan",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"atan2",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"sinh",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"cosh",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"tanh",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	//intrinsics - exponential
	{"pow",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"pow",TYPE_VEC2,{TYPE_VEC2,TYPE_FLOAT,TYPE_VOID}},
	{"pow",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"pow",TYPE_VEC3,{TYPE_VEC3,TYPE_FLOAT,TYPE_VOID}},
	{"pow",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"pow",TYPE_VEC4,{TYPE_VEC4,TYPE_FLOAT,TYPE_VOID}},
	{"pow",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"exp",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"exp",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"exp",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"exp",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"log",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"log",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"log",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"log",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"sqrt",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"sqrt",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"sqrt",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"sqrt",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	//intrinsics - common
	{"abs",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"abs",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"abs",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"abs",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"sign",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"sign",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"sign",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"sign",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"floor",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"floor",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"floor",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"floor",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"trunc",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"trunc",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"trunc",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"trunc",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"round",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"round",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"round",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"round",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"ceil",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"ceil",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"ceil",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"ceil",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"fract",TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{"fract",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"fract",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"fract",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"mod",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"mod",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"mod",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"mod",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"min",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"min",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"min",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"min",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"max",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"max",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"max",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"max",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"clamp",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"clamp",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"clamp",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"clamp",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"mix",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"mix",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_FLOAT,TYPE_VOID}},
	{"mix",TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"mix",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_FLOAT,TYPE_VOID}},
	{"mix",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"mix",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_FLOAT,TYPE_VOID}},
	{"mix",TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"step",TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT,TYPE_VOID}},
	{"step",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	//intrinsics - geometric
	{"length",TYPE_FLOAT,{TYPE_VEC2,TYPE_VOID}},
	{"length",TYPE_FLOAT,{TYPE_VEC3,TYPE_VOID}},
	{"length",TYPE_FLOAT,{TYPE_VEC4,TYPE_VOID}},
	{"distance",TYPE_FLOAT,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"distance",TYPE_FLOAT,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"distance",TYPE_FLOAT,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"dot",TYPE_FLOAT,{TYPE_VEC2,TYPE_VEC2,TYPE_VOID}},
	{"dot",TYPE_FLOAT,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"dot",TYPE_FLOAT,{TYPE_VEC4,TYPE_VEC4,TYPE_VOID}},
	{"cross",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	{"normalize",TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{"normalize",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{"normalize",TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{"reflect",TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3,TYPE_VOID}},
	//intrinsics - texture
	{"tex",TYPE_VEC4,{TYPE_TEXTURE,TYPE_VEC2,TYPE_VOID}},
	{"texcube",TYPE_VEC4,{TYPE_CUBEMAP,TYPE_VEC3,TYPE_VOID}},
	{"texscreen",TYPE_VEC3,{TYPE_VEC2,TYPE_VOID}},
	{"texpos",TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},

	{NULL,TYPE_VOID,{TYPE_VOID}}

};

const ShaderLanguage::OperatorDef ShaderLanguage::operator_defs[]={

	{OP_ASSIGN,TYPE_VOID,{TYPE_BOOL,TYPE_BOOL}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_VEC4,TYPE_VEC4}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_MAT3,TYPE_MAT3}},
	{OP_ASSIGN,TYPE_VOID,{TYPE_MAT4,TYPE_MAT4}},
	{OP_ADD,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ADD,TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ADD,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ADD,TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4}},
	{OP_SUB,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_SUB,TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2}},
	{OP_SUB,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_SUB,TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4}},
	{OP_MUL,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_MUL,TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2}},
	{OP_MUL,TYPE_VEC2,{TYPE_VEC2,TYPE_FLOAT}},
	{OP_MUL,TYPE_VEC2,{TYPE_FLOAT,TYPE_VEC2}},
	{OP_MUL,TYPE_VEC2,{TYPE_VEC2,TYPE_MAT3}},
	{OP_MUL,TYPE_VEC2,{TYPE_MAT3,TYPE_VEC2}},
	{OP_MUL,TYPE_VEC2,{TYPE_VEC2,TYPE_MAT4}},
	{OP_MUL,TYPE_VEC2,{TYPE_MAT4,TYPE_VEC2}},
	{OP_MUL,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_MUL,TYPE_VEC3,{TYPE_VEC3,TYPE_FLOAT}},
	{OP_MUL,TYPE_VEC3,{TYPE_FLOAT,TYPE_VEC3}},
	{OP_MUL,TYPE_VEC3,{TYPE_MAT3,TYPE_VEC3}},
	{OP_MUL,TYPE_VEC3,{TYPE_MAT4,TYPE_VEC3}},
	{OP_MUL,TYPE_VEC3,{TYPE_VEC3,TYPE_MAT3}},
	{OP_MUL,TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4}},
	{OP_MUL,TYPE_VEC4,{TYPE_VEC4,TYPE_FLOAT}},
	{OP_MUL,TYPE_VEC4,{TYPE_FLOAT,TYPE_VEC4}},
	{OP_MUL,TYPE_VEC4,{TYPE_MAT4,TYPE_VEC4}},
	{OP_MUL,TYPE_VEC4,{TYPE_VEC4,TYPE_MAT4}},
	{OP_MUL,TYPE_MAT3,{TYPE_MAT3,TYPE_MAT3}},
	{OP_MUL,TYPE_MAT4,{TYPE_MAT4,TYPE_MAT4}},
	{OP_DIV,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_DIV,TYPE_VEC2,{TYPE_VEC2,TYPE_VEC2}},
	{OP_DIV,TYPE_VEC2,{TYPE_VEC2,TYPE_FLOAT}},
	{OP_DIV,TYPE_VEC2,{TYPE_FLOAT,TYPE_VEC2}},
	{OP_DIV,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_DIV,TYPE_VEC3,{TYPE_VEC3,TYPE_FLOAT}},
	{OP_DIV,TYPE_VEC3,{TYPE_FLOAT,TYPE_VEC3}},
	{OP_DIV,TYPE_VEC4,{TYPE_VEC4,TYPE_VEC4}},
	{OP_DIV,TYPE_VEC4,{TYPE_VEC4,TYPE_FLOAT}},
	{OP_DIV,TYPE_VEC4,{TYPE_FLOAT,TYPE_VEC4}},
	{OP_ASSIGN_ADD,TYPE_VOID,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ASSIGN_ADD,TYPE_VOID,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ASSIGN_ADD,TYPE_VOID,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ASSIGN_ADD,TYPE_VOID,{TYPE_VEC4,TYPE_VEC4}},
	{OP_ASSIGN_SUB,TYPE_VOID,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ASSIGN_SUB,TYPE_VOID,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ASSIGN_SUB,TYPE_VOID,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ASSIGN_SUB,TYPE_VOID,{TYPE_VEC4,TYPE_VEC4}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC2,TYPE_FLOAT}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT3,TYPE_VEC2}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT4,TYPE_VEC2}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC3,TYPE_FLOAT}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT3,TYPE_VEC3}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT4,TYPE_VEC3}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC4,TYPE_VEC4}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_VEC4,TYPE_FLOAT}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT4,TYPE_VEC4}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT3,TYPE_MAT3}},
	{OP_ASSIGN_MUL,TYPE_VOID,{TYPE_MAT4,TYPE_MAT4}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC2,TYPE_VEC2}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC2,TYPE_FLOAT}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC3,TYPE_VEC3}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC3,TYPE_FLOAT}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC4,TYPE_VEC4}},
	{OP_ASSIGN_DIV,TYPE_VOID,{TYPE_VEC4,TYPE_FLOAT}},
	{OP_NEG,TYPE_FLOAT,{TYPE_FLOAT,TYPE_VOID}},
	{OP_NEG,TYPE_VEC2,{TYPE_VEC2,TYPE_VOID}},
	{OP_NEG,TYPE_VEC3,{TYPE_VEC3,TYPE_VOID}},
	{OP_NEG,TYPE_VEC4,{TYPE_VEC4,TYPE_VOID}},
	{OP_NOT,TYPE_BOOL,{TYPE_BOOL,TYPE_VOID}},
	{OP_CMP_EQ,TYPE_BOOL,{TYPE_BOOL,TYPE_BOOL}},
	{OP_CMP_EQ,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_EQ,TYPE_VEC2,{TYPE_VEC3,TYPE_VEC2}},
	{OP_CMP_EQ,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_CMP_EQ,TYPE_VEC4,{TYPE_VEC3,TYPE_VEC4}},
	//{OP_CMP_EQ,TYPE_MAT3,{TYPE_MAT4,TYPE_MAT3}}, ??
	//{OP_CMP_EQ,TYPE_MAT4,{TYPE_MAT4,TYPE_MAT4}}, ??
	{OP_CMP_NEQ,TYPE_BOOL,{TYPE_BOOL,TYPE_BOOL}},
	{OP_CMP_NEQ,TYPE_FLOAT,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_NEQ,TYPE_VEC3,{TYPE_VEC2,TYPE_VEC2}},
	{OP_CMP_NEQ,TYPE_VEC3,{TYPE_VEC3,TYPE_VEC3}},
	{OP_CMP_NEQ,TYPE_VEC3,{TYPE_VEC4,TYPE_VEC4}},
	//{OP_CMP_NEQ,TYPE_MAT4,{TYPE_MAT4,TYPE_MAT4}}, //?
	{OP_CMP_LEQ,TYPE_BOOL,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_GEQ,TYPE_BOOL,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_LESS,TYPE_BOOL,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_GREATER,TYPE_BOOL,{TYPE_FLOAT,TYPE_FLOAT}},
	{OP_CMP_OR,TYPE_BOOL,{TYPE_BOOL,TYPE_BOOL}},
	{OP_CMP_AND,TYPE_BOOL,{TYPE_BOOL,TYPE_BOOL}},
	{OP_MAX,TYPE_VOID,{TYPE_VOID,TYPE_VOID}}
};


const ShaderLanguage::BuiltinsDef ShaderLanguage::vertex_builtins_defs[]={

	{ "VERTEX", TYPE_VEC3},
	{ "NORMAL", TYPE_VEC3},
	{ "TANGENT", TYPE_VEC3},
	{ "BINORMAL", TYPE_VEC3},
	{ "UV", TYPE_VEC2},
	{ "UV2", TYPE_VEC2},
	{ "COLOR", TYPE_VEC4},
	{ "BONES", TYPE_VEC4},
	{ "WEIGHTS", TYPE_VEC4},
	{ "VAR1", TYPE_VEC4},
	{ "VAR2", TYPE_VEC4},
	{ "SPEC_EXP", TYPE_FLOAT},
	{ "POINT_SIZE", TYPE_FLOAT},

	//builtins
	{ "WORLD_MATRIX", TYPE_MAT4},
	{ "INV_CAMERA_MATRIX", TYPE_MAT4},
	{ "PROJECTION_MATRIX", TYPE_MAT4},
	{ "INSTANCE_ID", TYPE_FLOAT},
	{ "TIME", TYPE_FLOAT},
	{ NULL, TYPE_VOID},
};
const ShaderLanguage::BuiltinsDef ShaderLanguage::fragment_builtins_defs[]={

	{ "VERTEX", TYPE_VEC3},
	{ "POSITION", TYPE_VEC3},
	{ "NORMAL", TYPE_VEC3},
	{ "TANGENT", TYPE_VEC3},
	{ "BINORMAL", TYPE_VEC3},
	{ "UV", TYPE_VEC2},
	{ "UV2", TYPE_VEC2},
	{ "COLOR", TYPE_VEC4},
	{ "NORMAL", TYPE_VEC3},
	{ "VAR1", TYPE_VEC4},
	{ "VAR2", TYPE_VEC4},
	{ "DIFFUSE", TYPE_VEC3},
	{ "DIFFUSE_ALPHA", TYPE_VEC4},
	{ "SPECULAR", TYPE_VEC3},
	{ "EMISSION", TYPE_VEC3},
	{ "SPEC_EXP", TYPE_FLOAT},
	{ "GLOW", TYPE_FLOAT},
	{ "SHADE_PARAM", TYPE_FLOAT},
	{ "DISCARD", TYPE_FLOAT},
	{ "SCREEN_UV", TYPE_VEC2},
	{ "POINT_COORD", TYPE_VEC2},
	{ "INV_CAMERA_MATRIX", TYPE_MAT4},

//	{ "SCREEN_POS", TYPE_VEC2},
//	{ "SCREEN_TEXEL_SIZE", TYPE_VEC2},
	{ "TIME", TYPE_FLOAT},
	{ NULL, TYPE_VOID}

};
const ShaderLanguage::BuiltinsDef ShaderLanguage::postprocess_fragment_builtins_defs[]={

	{ "IN_COLOR", TYPE_VEC3},
	{ "IN_POSITION", TYPE_VEC3},
	{ "OUT_COLOR", TYPE_VEC3},
	{ "SCREEN_POS", TYPE_VEC2},
	{ "SCREEN_TEXEL_SIZE", TYPE_VEC2},
	{ "TIME", TYPE_FLOAT},
	{ NULL, TYPE_VOID}
};



ShaderLanguage::DataType ShaderLanguage::compute_node_type(Node *p_node) {

	switch(p_node->type) {

		case Node::TYPE_PROGRAM: ERR_FAIL_V(TYPE_VOID);
		case Node::TYPE_FUNCTION: return static_cast<FunctionNode*>(p_node)->return_type;
		case Node::TYPE_BLOCK: ERR_FAIL_V(TYPE_VOID);
		case Node::TYPE_VARIABLE: return static_cast<VariableNode*>(p_node)->datatype_cache;
		case Node::TYPE_CONSTANT: return static_cast<ConstantNode*>(p_node)->datatype;
		case Node::TYPE_OPERATOR: return static_cast<OperatorNode*>(p_node)->return_cache;
		case Node::TYPE_CONTROL_FLOW: ERR_FAIL_V(TYPE_VOID);
		case Node::TYPE_MEMBER: return static_cast<MemberNode*>(p_node)->datatype;
	}

	return TYPE_VOID;
}


ShaderLanguage::Node* ShaderLanguage::validate_function_call(Parser&parser, OperatorNode *p_func) {

	ERR_FAIL_COND_V(p_func->op!=OP_CALL && p_func->op!=OP_CONSTRUCT,NULL);


	Vector<DataType> args;

	ERR_FAIL_COND_V( p_func->arguments[0]->type!=Node::TYPE_VARIABLE, NULL );

	String name = static_cast<VariableNode*>(p_func->arguments[0])->name.operator String();

	bool all_const=true;
	for(int i=1;i<p_func->arguments.size();i++) {
		if (p_func->arguments[i]->type!=Node::TYPE_CONSTANT)
			all_const=false;
		args.push_back(compute_node_type(p_func->arguments[i]));
	}

	int argcount=args.size();

	bool found_intrinsic=false;

	if (argcount<=4) {
		// test intrinsics
		int idx=0;

		while (intrinsic_func_defs[idx].name) {

			if (name==intrinsic_func_defs[idx].name) {

				bool fail=false;
				for(int i=0;i<argcount;i++) {

					if (args[i]!=intrinsic_func_defs[idx].args[i]) {
						fail=true;
						break;
					}
				}

				if (!fail && argcount<4 && intrinsic_func_defs[idx].args[argcount]!=TYPE_VOID)
					fail=true; //make sure the number of arguments matches

				if (!fail) {
					p_func->return_cache=intrinsic_func_defs[idx].rettype;
					found_intrinsic=true;
					break;

				}

			}

			idx++;
		}
	}


	if (found_intrinsic) {

		if (p_func->op==OP_CONSTRUCT && all_const) {

			bool all_const=false;
			Vector<float> cdata;
			for(int i=0;i<argcount;i++) {

				Variant v = static_cast<ConstantNode*>(p_func->arguments[i+1])->value;
				switch(v.get_type()) {

					case Variant::REAL: cdata.push_back(v); break;
					case Variant::VECTOR2: { Vector2 v2=v; cdata.push_back(v2.x); cdata.push_back(v2.y); } break;
					case Variant::VECTOR3: { Vector3 v3=v; cdata.push_back(v3.x); cdata.push_back(v3.y); cdata.push_back(v3.z);} break;
					case Variant::PLANE: { Plane v4=v; cdata.push_back(v4.normal.x); cdata.push_back(v4.normal.y); cdata.push_back(v4.normal.z); cdata.push_back(v4.d); } break;
					default: ERR_FAIL_V(NULL);

				}

			}

			ConstantNode *cn = parser.create_node<ConstantNode>(p_func->parent);
			Variant data;
			switch(p_func->return_cache) {
				case TYPE_FLOAT: data = cdata[0]; break;
				case TYPE_VEC2: data = Vector2(cdata[0],cdata[1]); break;
				case TYPE_VEC3: data = Vector3(cdata[0],cdata[1],cdata[2]); break;
				case TYPE_VEC4: data = Plane(cdata[0],cdata[1],cdata[2],cdata[3]); break;
			}

			cn->datatype=p_func->return_cache;
			cn->value=data;
			return cn;

		}
		return p_func;
	}

	// try existing functions..

	FunctionNode *exclude_function=NULL; //exclude current function (in case inside one)


	Node *node = p_func;

	while(node->parent) {

		if (node->type==Node::TYPE_FUNCTION) {

			exclude_function = (FunctionNode*)node;
		}

		node=node->parent;
	}

	ERR_FAIL_COND_V(node->type!=Node::TYPE_PROGRAM,NULL);
	ProgramNode *program = (ProgramNode*)node;

	for(int i=0;i<program->functions.size();i++) {

		if (program->functions[i].function==exclude_function)
			continue;

		FunctionNode *pfunc = program->functions[i].function;

		if (pfunc->arguments.size()!=args.size())
			continue;

		bool fail=false;

		for(int i=0;i<args.size();i++) {
			if (args[i]!=pfunc->arguments[i].type) {
				fail=true;
				break;
			}
		}

		if (!fail) {
			p_func->return_cache=pfunc->return_type;
			return p_func;
		}
	}

	return NULL;
}


ShaderLanguage::Node * ShaderLanguage::validate_operator(Parser& parser,OperatorNode *p_func) {

	int argcount = p_func->arguments.size();
	ERR_FAIL_COND_V(argcount>2,NULL);

	DataType argtype[2]={TYPE_VOID,TYPE_VOID};
	bool all_const=true;

	for(int i=0;i<argcount;i++) {

		argtype[i]=compute_node_type(p_func->arguments[i]);
		if (p_func->arguments[i]->type!=Node::TYPE_CONSTANT)
			all_const=false;

	}
	int idx=0;

	bool valid=false;
	while(operator_defs[idx].op!=OP_MAX) {

		if (p_func->op==operator_defs[idx].op) {



			if (operator_defs[idx].args[0]==argtype[0] && operator_defs[idx].args[1]==argtype[1]) {

				p_func->return_cache=operator_defs[idx].rettype;
				valid=true;
				break;
			}
		}

		idx++;
	}

	if (!valid)
		return NULL;

#define _RCO2(m_op,m_vop)\
case m_op: {\
	ConstantNode *cn = parser.create_node<ConstantNode>(p_func->parent);\
	cn->datatype=p_func->return_cache;	\
	Variant::evaluate(m_vop,static_cast<ConstantNode*>(p_func->arguments[0])->value,static_cast<ConstantNode*>(p_func->arguments[1])->value,cn->value,valid);\
	if (!valid)\
		return NULL;\
	return cn;\
} break;

#define _RCO1(m_op,m_vop)\
case m_op: {\
	ConstantNode *cn = parser.create_node<ConstantNode>(p_func->parent);\
	cn->datatype=p_func->return_cache;	\
	Variant::evaluate(m_vop,static_cast<ConstantNode*>(p_func->arguments[0])->value,Variant(),cn->value,valid);\
	if (!valid)\
		return NULL;\
	return cn;\
} break;

	if (all_const) {
		//reduce constant operator
		switch(p_func->op) {
			_RCO2(OP_ADD,Variant::OP_ADD);
			_RCO2(OP_SUB,Variant::OP_SUBSTRACT);
			_RCO2(OP_MUL,Variant::OP_MULTIPLY);
			_RCO2(OP_DIV,Variant::OP_DIVIDE);
			_RCO1(OP_NEG,Variant::OP_NEGATE);
			_RCO1(OP_NOT,Variant::OP_NOT);
			_RCO2(OP_CMP_EQ,Variant::OP_EQUAL);
			_RCO2(OP_CMP_NEQ,Variant::OP_NOT_EQUAL);
			_RCO2(OP_CMP_LEQ,Variant::OP_LESS_EQUAL);
			_RCO2(OP_CMP_GEQ,Variant::OP_GREATER_EQUAL);
			_RCO2(OP_CMP_LESS,Variant::OP_LESS);
			_RCO2(OP_CMP_GREATER,Variant::OP_GREATER);
			_RCO2(OP_CMP_OR,Variant::OP_OR);
			_RCO2(OP_CMP_AND,Variant::OP_AND);
			default: {}
		}
	}


	return p_func;

}

bool ShaderLanguage::is_token_operator(TokenType p_type) {

	return (p_type==TK_OP_EQUAL) ||
	(p_type==TK_OP_NOT_EQUAL) ||
	(p_type==TK_OP_LESS) ||
	(p_type==TK_OP_LESS_EQUAL) ||
	(p_type==TK_OP_GREATER) ||
	(p_type==TK_OP_GREATER_EQUAL) ||
	(p_type==TK_OP_AND) ||
	(p_type==TK_OP_OR) ||
	(p_type==TK_OP_NOT) ||
	(p_type==TK_OP_ADD) ||
	(p_type==TK_OP_SUB) ||
	(p_type==TK_OP_MUL) ||
	(p_type==TK_OP_DIV) ||
	(p_type==TK_OP_NEG) ||
	(p_type==TK_OP_ASSIGN) ||
	(p_type==TK_OP_ASSIGN_ADD) ||
	(p_type==TK_OP_ASSIGN_SUB) ||
	(p_type==TK_OP_ASSIGN_MUL) ||
	(p_type==TK_OP_ASSIGN_DIV);

}
ShaderLanguage::Operator ShaderLanguage::get_token_operator(TokenType p_type) {

	switch(p_type) {
		case TK_OP_EQUAL: return OP_CMP_EQ ;
		case TK_OP_NOT_EQUAL: return OP_CMP_NEQ;
		case TK_OP_LESS: return OP_CMP_LESS ;
		case TK_OP_LESS_EQUAL: return OP_CMP_LEQ ;
		case TK_OP_GREATER: return OP_CMP_GREATER ;
		case TK_OP_GREATER_EQUAL: return OP_CMP_GEQ ;
		case TK_OP_AND: return OP_CMP_AND ;
		case TK_OP_OR: return OP_CMP_OR ;
		case TK_OP_NOT: return OP_NOT ;
		case TK_OP_ADD: return OP_ADD ;
		case TK_OP_SUB: return OP_SUB ;
		case TK_OP_MUL: return OP_MUL ;
		case TK_OP_DIV: return OP_DIV ;
		case TK_OP_NEG: return OP_NEG ;
		case TK_OP_ASSIGN: return OP_ASSIGN ;
		case TK_OP_ASSIGN_ADD: return OP_ASSIGN_ADD ;
		case TK_OP_ASSIGN_SUB: return OP_ASSIGN_SUB ;
		case TK_OP_ASSIGN_MUL: return OP_ASSIGN_MUL ;
		case TK_OP_ASSIGN_DIV: return OP_ASSIGN_DIV ;
		default: ERR_FAIL_V(OP_MAX);
	}

	return OP_MAX;
}


Error ShaderLanguage::parse_expression(Parser& parser,Node *p_parent,Node **r_expr) {

	Vector<Node*> expressions;
	Vector<TokenType> operators;

	while(true) {

		Node *expr=NULL;


		if (parser.get_token_type()==TK_PARENTHESIS_OPEN) {
			//handle subexpression
			parser.advance();
			Error err = parse_expression(parser,p_parent,&expr);
			if (err)
				return err;

			if (parser.get_token_type()!=TK_PARENTHESIS_CLOSE) {

				parser.set_error("Expected ')' in expression");
				return ERR_PARSE_ERROR;
			}

			parser.advance();

		} else if (parser.get_token_type()==TK_REAL_CONSTANT) {


			ConstantNode *constant = parser.create_node<ConstantNode>(p_parent);
			constant->value=parser.get_token().text.operator String().to_double();
			constant->datatype=TYPE_FLOAT;
			expr=constant;
			parser.advance();
		} else if (parser.get_token_type()==TK_TRUE) {
			//print_line("found true");

			//handle true constant
			ConstantNode *constant = parser.create_node<ConstantNode>(p_parent);
			constant->value=true;
			constant->datatype=TYPE_BOOL;
			expr=constant;
			parser.advance();
		} else if (parser.get_token_type()==TK_FALSE) {

			//handle false constant
			ConstantNode *constant = parser.create_node<ConstantNode>(p_parent);
			constant->value=false;
			constant->datatype=TYPE_BOOL;
			expr=constant;
			parser.advance();
		} else if (parser.get_token_type()==TK_TYPE_VOID) {

			//make sure void is not used in expression
			parser.set_error("Void value not allowed in Expression");
			return ERR_PARSE_ERROR;
		} else if (parser.get_token_type(1)==TK_PARENTHESIS_OPEN && (is_token_nonvoid_datatype(parser.get_token_type()) || parser.get_token_type()==TK_INDENTIFIER)) {


			//function or constructor
			StringName name;
			DataType constructor=TYPE_VOID;
			if (is_token_nonvoid_datatype(parser.get_token_type())) {

				constructor=get_token_datatype(parser.get_token_type());
				switch(get_token_datatype(parser.get_token_type())) {
				   case TYPE_BOOL: name="bool"; break;
				   case TYPE_FLOAT: name="float"; break;
				   case TYPE_VEC2: name="vec2"; break;
				   case TYPE_VEC3: name="vec3"; break;
				   case TYPE_VEC4: name="vec4"; break;
				   case TYPE_MAT3: name="mat3"; break;
				   case TYPE_MAT4: name="mat4"; break;
				   default: ERR_FAIL_V(ERR_BUG);
				}
			} else {

				name=parser.get_token().text;
			}

			if (!test_existing_identifier(p_parent,name)) {

				parser.set_error("Unknown identifier in expression: "+name);
				return ERR_PARSE_ERROR;
			}

			parser.advance(2);

			OperatorNode *func = parser.create_node<OperatorNode>(p_parent);

			func->op=constructor!=TYPE_VOID?OP_CONSTRUCT:OP_CALL;

			VariableNode *funcname = parser.create_node<VariableNode>(func);
			funcname->name=name;
			func->arguments.push_back(funcname);

			//parse parameters

			if (parser.get_token_type()==TK_PARENTHESIS_CLOSE) {
				parser.advance();
			} else {

				while(true) {


					Node *arg=NULL;
					Error err = parse_expression(parser,func,&arg);
					if (err)
						return err;
					func->arguments.push_back(arg);

					if (parser.get_token_type()==TK_PARENTHESIS_CLOSE) {
						parser.advance();
						break;

					} else if (parser.get_token_type()==TK_COMMA) {

						if (parser.get_token_type(1)==TK_PARENTHESIS_CLOSE) {

							parser.set_error("Expression expected");
							return ERR_PARSE_ERROR;
						}

						parser.advance();
					} else {
						// something is broken
						parser.set_error("Expected ',' or ')'");
						return ERR_PARSE_ERROR;
					}

				}
			}

			expr=validate_function_call(parser,func);
			if (!expr) {

				parser.set_error("Invalid arguments to function/constructor: "+StringName(name));
				return ERR_PARSE_ERROR;

			}

		} else if (parser.get_token_type()==TK_INDENTIFIER) {
			//probably variable


			Node *node =p_parent;
			bool existing=false;
			DataType datatype;
			StringName identifier=parser.get_token().text;

			while(node) {

				if (node->type==Node::TYPE_BLOCK) {

					BlockNode *block = (BlockNode*)node;

					if (block->variables.has(identifier)) {
						existing=true;
						datatype=block->variables[identifier];
						break;
					}
				}

				if (node->type==Node::TYPE_FUNCTION) {

					FunctionNode *function=(FunctionNode*)node;
					for(int i=0;i<function->arguments.size();i++) {
						if (function->arguments[i].name==identifier) {
							existing=true;
							datatype=function->arguments[i].type;
							break;
						}
					}

					if (existing)
						break;

				}

				if (node->type==Node::TYPE_PROGRAM) {

					ProgramNode *program = (ProgramNode*)node;
					if (program->builtin_variables.has(identifier)) {
						datatype = program->builtin_variables[identifier];
						existing=true;
						break;
					}
					if (program->uniforms.has(identifier)) {
						datatype = program->uniforms[identifier].type;
						existing=true;
						break;
					}

				}

				node=node->parent;
			}

			if (!existing) {

				parser.set_error("Unexisting identifier in expression: "+identifier);
				return ERR_PARSE_ERROR;

			}

			VariableNode *varname = parser.create_node<VariableNode>(p_parent);
			varname->name=identifier;
			varname->datatype_cache=datatype;
			parser.advance();
			expr=varname;

		} else if (parser.get_token_type()==TK_OP_NEG || parser.get_token_type()==TK_OP_NOT) {

			//single prefix operators
			TokenType token_type=parser.get_token_type();
			parser.advance();
			Node *subexpr=NULL;
			Error err = parse_expression(parser,p_parent,&subexpr);
			if (err)
				return err;

			OperatorNode *op = parser.create_node<OperatorNode>(p_parent);
			switch(token_type) {
				case TK_OP_NEG: op->op=OP_NEG; break;
				case TK_OP_NOT: op->op=OP_NOT; break;
				//case TK_OP_PLUS_PLUS: op->op=OP_PLUS_PLUS; break;
				//case TK_OP_MINUS_MINUS: op->op=OP_MINUS_MINUS; break;
				default: ERR_FAIL_V(ERR_BUG);
			}

			op->arguments.push_back(subexpr);

			expr=validate_operator(parser,op);

			if (!expr) {

				parser.set_error("Invalid argument for negation operator");
				return ERR_PARSE_ERROR;
			}

		} else {
			print_line("found bug?");
			print_line("misplaced token: "+String(token_names[parser.get_token_type()]));

			parser.set_error("Error parsing expression, misplaced: "+String(token_names[parser.get_token_type()]));
			return ERR_PARSE_ERROR;
			//nothing
		}

		ERR_FAIL_COND_V(!expr,ERR_BUG);


		/* OK now see what's NEXT to the operator.. */
		/* OK now see what's NEXT to the operator.. */
		/* OK now see what's NEXT to the operator.. */


		if (parser.get_token_type()==TK_PERIOD) {

			if (parser.get_token_type(1)!=TK_INDENTIFIER) {
				parser.set_error("Expected identifier as member");
				return ERR_PARSE_ERROR;
			}

			DataType dt = compute_node_type(expr);
			String ident = parser.get_token(1).text;

			bool ok=true;
			DataType member_type;
			switch(dt) {
				case TYPE_VEC2: {

					int l = ident.length();
					if (l==1) {
						member_type=TYPE_FLOAT;
					} else if (l==2) {
						member_type=TYPE_VEC2;
					} else {
						ok=false;
						break;
					}

					const CharType *c=ident.ptr();
					for(int i=0;i<l;i++) {

						switch(c[i]) {
							case 'r':
							case 'g':
							case 'x':
							case 'y':
								break;
							default:
								ok=false;
								break;
						}
					}

				} break;
				case TYPE_VEC3: {

					int l = ident.length();
					if (l==1) {
						member_type=TYPE_FLOAT;
					} else if (l==2) {
						member_type=TYPE_VEC2;
					} else if (l==3) {
						member_type=TYPE_VEC3;
					} else {
						ok=false;
						break;
					}

					const CharType *c=ident.ptr();
					for(int i=0;i<l;i++) {

						switch(c[i]) {
							case 'r':
							case 'g':
							case 'b':
							case 'x':
							case 'y':
							case 'z':
								break;
							default:
								ok=false;
								break;
						}
					}

				} break;
				case TYPE_VEC4: {

					int l = ident.length();
					if (l==1) {
						member_type=TYPE_FLOAT;
					} else if (l==2) {
						member_type=TYPE_VEC2;
					} else if (l==3) {
						member_type=TYPE_VEC3;
					} else if (l==4) {
						member_type=TYPE_VEC4;
					} else {
						ok=false;
						break;
					}

					const CharType *c=ident.ptr();
					for(int i=0;i<l;i++) {

						switch(c[i]) {
							case 'r':
							case 'g':
							case 'b':
							case 'a':
							case 'x':
							case 'y':
							case 'z':
							case 'w':
								break;
							default:
								ok=false;
								break;
						}
					}

				} break;
				case TYPE_MAT3: ok=(ident=="x" || ident=="y" || ident=="z" ); member_type=TYPE_VEC3; break;
				case TYPE_MAT4: ok=(ident=="x" || ident=="y" || ident=="z" || ident=="w"); member_type=TYPE_VEC4; break;
				default: {}
			}

			if (!ok) {

				parser.set_error("Invalid member for expression: ."+ident);
				return ERR_PARSE_ERROR;
			}

			MemberNode *mn = parser.create_node<MemberNode>(p_parent);
			mn->basetype=dt;
			mn->datatype=member_type;
			mn->name=ident;
			mn->owner=expr;
			expr=mn;

			parser.advance(2);
			//todo
			//member (period) has priority over any operator
			//creates a subindexing expression in place


		} else if (parser.get_token_type()==TK_BRACKET_OPEN) {
			//todo
			//subindexing has priority over any operator
			//creates a subindexing expression in place


		} /*else if (parser.get_token_type()==TK_OP_PLUS_PLUS || parser.get_token_type()==TK_OP_MINUS_MINUS) {
			//todo
			//inc/dec operators have priority over any operator
			//creates a subindexing expression in place
			//return OK; //wtfs

		} */


		expressions.push_back(expr);


		if (is_token_operator(parser.get_token_type())) {

			operators.push_back(parser.get_token_type());
			parser.advance();
		} else {
			break;
		}
	}

	ERR_FAIL_COND_V(expressions.size()!=(operators.size()+1),ERR_BUG);

	/* Reduce the set set of expressions and place them in an operator tree, respecting precedence */

	while(expressions.size()>1) {

		int next_op=-1;
		int min_priority=0xFFFFF;

		for(int i=0;i<operators.size();i++) {

			int priority;
			switch(operators[i]) {

				case TK_OP_MUL: priority=0; break;
				case TK_OP_DIV: priority=0; break;

				case TK_OP_ADD: priority=1; break;
				case TK_OP_SUB: priority=1; break;

				// shift left/right =2

				case TK_OP_LESS: priority=3; break;
				case TK_OP_LESS_EQUAL: priority=3; break;
				case TK_OP_GREATER: priority=3; break;
				case TK_OP_GREATER_EQUAL: priority=3; break;

				case TK_OP_EQUAL: priority=4; break;
				case TK_OP_NOT_EQUAL: priority=4; break;

				//bit and =5
				//bit xor =6
				//bit or=7

				case TK_OP_AND: priority=8; break;
				case TK_OP_OR: priority=9; break;

				// ?: = 10

				case TK_OP_ASSIGN_ADD: priority=11; break;
				case TK_OP_ASSIGN_SUB: priority=11; break;
				case TK_OP_ASSIGN_MUL: priority=11; break;
				case TK_OP_ASSIGN_DIV: priority=11; break;
				case TK_OP_ASSIGN: priority=11; break;

				default: ERR_FAIL_V(ERR_BUG); //unexpected operator

			}

			if (priority<min_priority) {
				// < is used for left to right (default)
				// <= is used for right to left
				next_op=i;
				min_priority=priority;
			}

		}

		ERR_FAIL_COND_V(next_op==-1,ERR_BUG);

		// OK! create operator..

		OperatorNode *op = parser.create_node<OperatorNode>(p_parent);
		op->op=get_token_operator(operators[next_op]);

		op->arguments.push_back(expressions[next_op]); //expression goes as left
		op->arguments.push_back(expressions[next_op+1]); //next expression goes as right

		expressions[next_op]=validate_operator(parser,op);
		if (!expressions[next_op]) {

			String at;
			for(int i=0;i<op->arguments.size();i++) {
				if (i>0)
					at+=" and ";
				at+=get_datatype_name(compute_node_type(op->arguments[i]));

			}
			parser.set_error("Invalid arguments to operator "+String(token_names[operators[next_op]])+": "+at);
			return ERR_PARSE_ERROR;
		}


		expressions.remove(next_op+1);
		operators.remove(next_op);

	}

	*r_expr=expressions[0];

	return OK;

/*
			TokenType token_type=parser.get_token_type();
			OperatorNode *op = parser.create_node<OperatorNode>(p_parent);
			op->op=get_token_operator(parser.get_token_type());

			op->arguments.push_back(*r_expr); //expression goes as left
			parser.advance();
			Node *right_expr=NULL;
			Error err = parse_expression(parser,p_parent,&right_expr);
			if (err)
				return err;
			op->arguments.push_back(right_expr);

			if (!validate_operator(op)) {

				parser.set_error("Invalid arguments to operator "+String(token_names[token_type]));
				return ERR_PARSE_ERROR;
			}

*/

}

Error ShaderLanguage::parse_variable_declaration(Parser& parser,BlockNode *p_block) {

	bool uniform = parser.get_token(-1).type==TK_UNIFORM;

	DataType type=get_token_datatype(parser.get_token_type(0));
	bool iscolor = parser.get_token_type(0)==TK_TYPE_COLOR;

	if (type==TYPE_VOID) {

		parser.set_error("Cannot Declare a 'void' Variable");
		return ERR_PARSE_ERROR;
	}

	if (type==TYPE_TEXTURE && !uniform) {

		parser.set_error("Cannot Declare a Non-Uniform Texture");
		return ERR_PARSE_ERROR;
	}
	if (type==TYPE_CUBEMAP && !uniform) {

		parser.set_error("Cannot Declare a Non-Uniform Cubemap");
		return ERR_PARSE_ERROR;
	}


	parser.advance();
	int found=0;

	while(true) {


		if (found && parser.get_token_type()!=TK_COMMA) {
			break;
		}

		if (parser.get_token_type()!=TK_INDENTIFIER) {

			parser.set_error("Identifier Expected");
			return ERR_PARSE_ERROR;

		}

		StringName name = parser.get_token().text;

		if (test_existing_identifier(p_block,name)) {
			parser.set_error("Duplicate Identifier (existing variable/function): "+name);
			return ERR_PARSE_ERROR;
		}

		found=true;

		parser.advance();
		//see if declaration has an initializer
		if (parser.get_token_type()==TK_OP_ASSIGN) {
			parser.advance();
			OperatorNode * op = parser.create_node<OperatorNode>(p_block);
			VariableNode * var = parser.create_node<VariableNode>(op);
			var->name=name;
			var->datatype_cache=type;
			var->uniform=uniform;
			Node *expr;
			Error err = parse_expression(parser,p_block,&expr);

			if (err)
				return err;

			if (var->uniform) {

				if (expr->type!=Node::TYPE_CONSTANT) {

					parser.set_error("Uniform can only be initialized to a constant.");
					return ERR_PARSE_ERROR;
				}

				Uniform u;
				u.order=parser.program->uniforms.size();
				u.type=type;
				u.default_value=static_cast<ConstantNode*>(expr)->value;
				if (iscolor && u.default_value.get_type()==Variant::PLANE) {
					Color c;
					Plane p = u.default_value;
					c=Color(p.normal.x,p.normal.y,p.normal.z,p.d);
					u.default_value=c;
				}
				parser.program->uniforms[var->name]=u;
			} else {
				op->op=OP_ASSIGN;
				op->arguments.push_back(var);
				op->arguments.push_back(expr);
				Node *n=validate_operator(parser,op);
				if (!n) {
					parser.set_error("Invalid initializer for variable: "+name);
					return ERR_PARSE_ERROR;
				}
				p_block->statements.push_back(n);
			}

		} else {
			//initialize it EMPTY

			OperatorNode * op = parser.create_node<OperatorNode>(p_block);
			VariableNode * var = parser.create_node<VariableNode>(op);
			ConstantNode * con = parser.create_node<ConstantNode>(op);

			var->name=name;
			var->datatype_cache=type;
			var->uniform=uniform;
			con->datatype=type;

			switch(type) {
				case TYPE_BOOL: con->value=false; break;
				case TYPE_FLOAT: con->value=0.0; break;
				case TYPE_VEC2: con->value=Vector2(); break;
				case TYPE_VEC3: con->value=Vector3(); break;
				case TYPE_VEC4: con->value=iscolor?Variant(Color()):Variant(Plane()); break;
				case TYPE_MAT3: con->value=Matrix3(); break;
				case TYPE_MAT4: con->value=Transform(); break;
				case TYPE_TEXTURE:
				case TYPE_CUBEMAP: con->value=RID(); break;
				default: {}
			}

			if (uniform) {
				Uniform u;
				u.type=type;
				u.default_value=con->value;
				u.order=parser.program->uniforms.size();
				parser.program->uniforms[var->name]=u;

			} else {
				op->op=OP_ASSIGN;
				op->arguments.push_back(var);
				op->arguments.push_back(con);
				p_block->statements.push_back(op);
			}

		}

		if (!uniform)
			p_block->variables[name]=type;

	}

	if (parser.get_token_type()!=TK_SEMICOLON) {
		parser.set_error("Expected ';'");
		return ERR_PARSE_ERROR;
	}


	return OK;

}

Error ShaderLanguage::parse_flow_if(Parser& parser,Node *p_parent,Node **r_statement) {

	ControlFlowNode *cf = parser.create_node<ControlFlowNode>(p_parent);

	cf->flow_op=FLOW_OP_IF;

	parser.advance();

	if (parser.get_token_type()!=TK_PARENTHESIS_OPEN) {
		parser.set_error("Expected '(' after 'if'");
		return ERR_PARSE_ERROR;
	}
	parser.advance();

	Node *expression=NULL;
	Error err = parse_expression(parser,cf,&expression);
	if (err)
		return err;

	if (compute_node_type(expression)!=TYPE_BOOL) {

		parser.set_error("Expression for 'if' is not boolean");
		return ERR_PARSE_ERROR;
	}

	cf->statements.push_back(expression);

	if (parser.get_token_type()!=TK_PARENTHESIS_CLOSE) {
		parser.set_error("Expected ')' after expression");
		return ERR_PARSE_ERROR;
	}

	parser.advance();

	Node *substatement=NULL;
	err = parse_statement(parser,cf,&substatement);
	if (err)
		return err;


	cf->statements.push_back(substatement);



	if (parser.get_token_type()==TK_CF_ELSE) {

		parser.advance();
		substatement=NULL;
		err = parse_statement(parser,cf,&substatement);
		if (err)
			return err;

		cf->statements.push_back(substatement);
	}



	*r_statement=cf;

	return OK;
}

Error ShaderLanguage::parse_flow_return(Parser& parser,Node *p_parent,Node **r_statement) {


	FunctionNode *function=NULL;

	Node *parent=p_parent;

	while(parent) {

		if (parent->type==Node::TYPE_FUNCTION) {

			function=(FunctionNode*)parent;
			break;
		}

		parent=parent->parent;
	}

	if (!function) {

		parser.set_error("'return' must be inside a function");
		return ERR_PARSE_ERROR;
	}

	ControlFlowNode *cf = parser.create_node<ControlFlowNode>(p_parent);

	cf->flow_op=FLOW_OP_RETURN;

	parser.advance();

	if (function->return_type!=TYPE_VOID) {
		// should expect a return expression.

		Node *expr=NULL;
		Error err = parse_expression(parser,cf,&expr);
		if (err)
			return err;

		if (compute_node_type(expr)!=function->return_type) {
			parser.set_error("Invalid type for 'return' expression");
			return ERR_PARSE_ERROR;
		}
		cf->statements.push_back(expr);
	}

	*r_statement=cf;


	if (parser.get_token_type()!=TK_SEMICOLON) {
		parser.set_error("Expected ';'");
		return ERR_PARSE_ERROR;
	}

	return OK;
}

Error ShaderLanguage::parse_statement(Parser& parser,Node *p_parent,Node **r_statement) {

	*r_statement=NULL;

	TokenType token_type = parser.get_token_type();

	if (token_type==TK_CURLY_BRACKET_OPEN) {
		//sub-block
		parser.advance();
		BlockNode *block = parser.create_node<BlockNode>(p_parent);

		*r_statement=block;
		return parse_block(parser,block);
	} else if (token_type==TK_SEMICOLON) {
		// empty ;
		parser.advance();
		return OK;
	} else if (token_type==TK_CF_IF) {
		return parse_flow_if(parser,p_parent,r_statement);

	} else if (token_type==TK_CF_RETURN) {
		return parse_flow_return(parser,p_parent,r_statement);
	} else {
		Error err=parse_expression(parser,p_parent,r_statement);

		if (err)
			return err;

		if (parser.get_token_type()!=TK_SEMICOLON) {
			parser.set_error("Expected ';'");
			return ERR_PARSE_ERROR;
		}

	}

	return OK;
}

Error ShaderLanguage::parse_block(Parser& parser,BlockNode *p_block) {

	while(true) {

		if (parser.is_at_end()) {
			if (p_block->parent->type!=Node::TYPE_PROGRAM) {
				parser.set_error("Unexpected End of File");
				return ERR_PARSE_ERROR;
			}
			return OK; //bye
		}

		TokenType token_type = parser.get_token_type();

		if (token_type==TK_CURLY_BRACKET_CLOSE) {
			if (p_block->parent->type==Node::TYPE_PROGRAM) {
				parser.set_error("Unexpected '}'");
				return ERR_PARSE_ERROR;
			}
			parser.advance();
			return OK; // exit block

		} else if (token_type==TK_UNIFORM) {

			if (p_block!=parser.program->body) {

				parser.set_error("Uniform only allowed in main program body.");
				return ERR_PARSE_ERROR;
			}
			parser.advance();
			Error err=parse_variable_declaration(parser,p_block);
			if (err)
				return err;

		} else if (is_token_datatype(token_type)) {

			Error err=OK;
			if (parser_is_at_function(parser))
				err = parse_function(parser,p_block);
			else {
				err = parse_variable_declaration(parser,p_block);
			}

			if (err)
				return err;

		} else {
			// must be a statement
			Node *statement=NULL;

			Error err = parse_statement(parser,p_block,&statement);
			if (err)
				return err;
			if (statement) {
				p_block->statements.push_back(statement);
			}

		}
	}

	return OK;
}



Error ShaderLanguage::parse(const Vector<Token>& p_tokens,ShaderType p_type,CompileFunc p_compile_func,void *p_userdata,String *r_error,int *r_err_line,int *r_err_column) {


	uint64_t t = OS::get_singleton()->get_ticks_usec();

	Parser parser(p_tokens);
	parser.program = parser.create_node<ProgramNode>(NULL);
	parser.program->body = parser.create_node<BlockNode>(parser.program);


	//add builtins
	switch(p_type)	{
		case SHADER_MATERIAL_VERTEX: {
			int idx=0;
			while (vertex_builtins_defs[idx].name) {
				parser.program->builtin_variables[vertex_builtins_defs[idx].name]=vertex_builtins_defs[idx].type;
				idx++;
			}
		} break;
		case SHADER_MATERIAL_FRAGMENT: {
			int idx=0;
			while (fragment_builtins_defs[idx].name) {
				parser.program->builtin_variables[fragment_builtins_defs[idx].name]=fragment_builtins_defs[idx].type;
				idx++;
			}
		} break;
		case SHADER_POST_PROCESS: {
			int idx=0;
			while (postprocess_fragment_builtins_defs[idx].name) {
				parser.program->builtin_variables[postprocess_fragment_builtins_defs[idx].name]=postprocess_fragment_builtins_defs[idx].type;
				idx++;
			}
		} break;
	}

	Error err = parse_block(parser,parser.program->body);
	if (err) {
		parser.get_error(r_error,r_err_line,r_err_column);
		return err;
	}

	double tf = (OS::get_singleton()->get_ticks_usec()-t)/1000.0;
	//print_line("parse time: "+rtos(tf));

	t = OS::get_singleton()->get_ticks_usec();

	if (p_compile_func)
		p_compile_func(p_userdata,parser.program);

	tf = (OS::get_singleton()->get_ticks_usec()-t)/1000.0;
	//print_line("compile time: "+rtos(tf));

	//clean up nodes created
	while(parser.nodegc.size()) {

		memdelete( parser.nodegc.front()->get() );
		parser.nodegc.pop_front();
	}
	return OK;
}

Error ShaderLanguage::compile(const String& p_code,ShaderType p_type,CompileFunc p_compile_func,void *p_userdata,String *r_error,int *r_err_line,int *r_err_column) {

	*r_error="";
	*r_err_line=0;
	*r_err_column=0;
	Vector<Token> tokens;

	uint64_t t = OS::get_singleton()->get_ticks_usec();

	Error err = tokenize(p_code,&tokens,r_error,r_err_line,r_err_column);

	double tf = (OS::get_singleton()->get_ticks_usec()-t)/1000.0;
	//print_line("tokenize time: "+rtos(tf));

	if (err!=OK) {
		return err;
	}
	err = parse(tokens,p_type,p_compile_func,p_userdata,r_error,r_err_line,r_err_column);
	if (err!=OK) {
		//print_line("LDEBUG: "+lex_debug(p_code));
		return err;
	}
	return OK;
}


void ShaderLanguage::get_keyword_list(ShaderType p_type, List<String> *p_keywords) {

	int idx=0;

	while(intrinsic_func_defs[idx].name) {

		p_keywords->push_back(intrinsic_func_defs[idx].name);
		idx++;
	}

	switch(p_type)	{
		case SHADER_MATERIAL_VERTEX: {
			idx=0;
			while (vertex_builtins_defs[idx].name) {
				p_keywords->push_back(vertex_builtins_defs[idx].name);
				idx++;
			}
		} break;
		case SHADER_MATERIAL_FRAGMENT: {
			idx=0;
			while (fragment_builtins_defs[idx].name) {
				p_keywords->push_back(fragment_builtins_defs[idx].name);
				idx++;
			}
		} break;
		case SHADER_POST_PROCESS: {
			idx=0;
			while (postprocess_fragment_builtins_defs[idx].name) {
				p_keywords->push_back(postprocess_fragment_builtins_defs[idx].name);
				idx++;
			}
		} break;

	}

}
