/*
 * Copyright 2011-2015 Branimir Karadzic. All rights reserved.
 * License: http://www.opensource.org/licenses/BSD-2-Clause
 */

#include "shaderc.h"

bool g_verbose = false;

#define MAX_TAGS 256
extern "C"
{
#include <fcpp/fpp.h>
} // extern "C"

#define BGFX_CHUNK_MAGIC_CSH BX_MAKEFOURCC('C', 'S', 'H', 0x2)
#define BGFX_CHUNK_MAGIC_FSH BX_MAKEFOURCC('F', 'S', 'H', 0x4)
#define BGFX_CHUNK_MAGIC_VSH BX_MAKEFOURCC('V', 'S', 'H', 0x4)

long int fsize(FILE* _file)
{
	long int pos = ftell(_file);
	fseek(_file, 0L, SEEK_END);
	long int size = ftell(_file);
	fseek(_file, pos, SEEK_SET);
	return size;
}

static const char* s_ARB_shader_texture_lod[] =
{
	"texture2DLod",
	"texture2DProjLod",
	"texture3DLod",
	"texture3DProjLod",
	"textureCubeLod",
	"shadow2DLod",
	"shadow2DProjLod",
	NULL
	// "texture1DLod",
	// "texture1DProjLod",
	// "shadow1DLod",
	// "shadow1DProjLod",
};

static const char* s_EXT_shadow_samplers[] =
{
	"shadow2D",
	"shadow2DProj",
	"sampler2DShadow",
	NULL
};

static const char* s_OES_standard_derivatives[] =
{
	"dFdx",
	"dFdy",
	"fwidth",
	NULL
};

static const char* s_OES_texture_3D[] =
{
	"texture3D",
	"texture3DProj",
	"texture3DLod",
	"texture3DProjLod",
	NULL
};

static const char* s_130[] =
{
	"uint",
	"uint2",
	"uint3",
	"uint4",
	"isampler3D",
	"usampler3D",
	NULL
};

const char* s_uniformTypeName[UniformType::Count] =
{
	"int",
	NULL,
	"vec4",
	"mat3",
	"mat4",
};

const char* interpolationDx11(const char* _glsl)
{
	if (0 == strcmp(_glsl, "smooth") )
	{
		return "linear";
	}
	else if (0 == strcmp(_glsl, "flat") )
	{
		return "nointerpolation";
	}

	return _glsl; // noperspective
}

const char* getUniformTypeName(UniformType::Enum _enum)
{
	return s_uniformTypeName[_enum];
}

UniformType::Enum nameToUniformTypeEnum(const char* _name)
{
	for (uint32_t ii = 0; ii < UniformType::Count; ++ii)
	{
		if (NULL != s_uniformTypeName[ii]
		&&  0 == strcmp(_name, s_uniformTypeName[ii]) )
		{
			return UniformType::Enum(ii);
		}
	}

	return UniformType::Count;
}

int32_t writef(bx::WriterI* _writer, const char* _format, ...)
{
	va_list argList;
	va_start(argList, _format);

	char temp[2048];

	char* out = temp;
	int32_t max = sizeof(temp);
	int32_t len = bx::vsnprintf(out, max, _format, argList);
	if (len > max)
	{
		out = (char*)alloca(len);
		len = bx::vsnprintf(out, len, _format, argList);
	}

	len = bx::write(_writer, out, len);

	va_end(argList);

	return len;
}

struct Varying
{
	std::string m_precision;
	std::string m_interpolation;
	std::string m_name;
	std::string m_type;
	std::string m_init;
	std::string m_semantics;
};

typedef std::unordered_map<std::string, Varying> VaryingMap;

class File
{
public:
	File(const char* _filePath)
		: m_data(NULL)
	{
		FILE* file = fopen(_filePath, "r");
		if (NULL != file)
		{
			m_size = fsize(file);
			m_data = new char[m_size+1];
			m_size = (uint32_t)fread(m_data, 1, m_size, file);
			m_data[m_size] = '\0';
			fclose(file);
		}
	}

	~File()
	{
		delete [] m_data;
	}

	const char* getData() const
	{
		return m_data;
	}

	uint32_t getSize() const
	{
		return m_size;
	}

private:
	char* m_data;
	uint32_t m_size;
};

void strins(char* _str, const char* _insert)
{
	size_t len = strlen(_insert);
	memmove(&_str[len], _str, strlen(_str) );
	memcpy(_str, _insert, len);
}

void strreplace(char* _str, const char* _find, const char* _replace)
{
	const size_t len = strlen(_find);

	char* replace = (char*)alloca(len+1);
	bx::strlcpy(replace, _replace, len+1);
	for (size_t ii = strlen(replace); ii < len; ++ii)
	{
		replace[ii] = ' ';
	}
	replace[len] = '\0';

	BX_CHECK(len >= strlen(_replace), "");
	for (char* ptr = strstr(_str, _find); NULL != ptr; ptr = strstr(ptr + len, _find) )
	{
		memcpy(ptr, replace, len);
	}
}

void printCode(const char* _code, int32_t _line, int32_t _start, int32_t _end)
{
	fprintf(stderr, "Code:\n---\n");

	LineReader lr(_code);
	for (int32_t line = 1; !lr.isEof() && line < _end; ++line)
	{
		if (line >= _start)
		{
			fprintf(stderr, "%s%3d: %s", _line == line ? ">>> " : "    ", line, lr.getLine().c_str() );
		}
		else
		{
			lr.skipLine();
		}
	}

	fprintf(stderr, "---\n");
}

struct Preprocessor
{
	Preprocessor(const char* _filePath, bool _gles, const char* _includeDir = NULL)
		: m_tagptr(m_tags)
		, m_scratchPos(0)
		, m_fgetsPos(0)
	{
		m_tagptr->tag = FPPTAG_USERDATA;
		m_tagptr->data = this;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_DEPENDS;
		m_tagptr->data = (void*)fppDepends;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_INPUT;
		m_tagptr->data = (void*)fppInput;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_OUTPUT;
		m_tagptr->data = (void*)fppOutput;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_ERROR;
		m_tagptr->data = (void*)fppError;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_IGNOREVERSION;
		m_tagptr->data = (void*)0;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_LINE;
		m_tagptr->data = (void*)0;
		m_tagptr++;

		m_tagptr->tag = FPPTAG_INPUT_NAME;
		m_tagptr->data = scratch(_filePath);
		m_tagptr++;

		if (NULL != _includeDir)
		{
			addInclude(_includeDir);
		}

		if (!_gles)
		{
			m_default = "#define lowp\n#define mediump\n#define highp\n";
		}
	}

	void setDefine(const char* _define)
	{
		m_tagptr->tag = FPPTAG_DEFINE;
		m_tagptr->data = scratch(_define);
		m_tagptr++;
	}

	void setDefaultDefine(const char* _name)
	{
		char temp[1024];
		bx::snprintf(temp, BX_COUNTOF(temp)
			, "#ifndef %s\n"
			  "#	define %s 0\n"
			  "#endif // %s\n"
			  "\n"
			, _name
			, _name
			, _name
			);

		m_default += temp;
	}

	void writef(const char* _format, ...)
	{
		va_list argList;
		va_start(argList, _format);
		bx::stringPrintfVargs(m_default, _format, argList);
		va_end(argList);
	}

	void addInclude(const char* _includeDir)
	{
		char* start = scratch(_includeDir);

		for (char* split = strchr(start, ';'); NULL != split; split = strchr(start, ';'))
		{
			*split = '\0';
			m_tagptr->tag = FPPTAG_INCLUDE_DIR;
			m_tagptr->data = start;
			m_tagptr++;
			start = split + 1;
		}

		m_tagptr->tag = FPPTAG_INCLUDE_DIR;
		m_tagptr->data = start;
		m_tagptr++;
	}

	void addDependency(const char* _fileName)
	{
		m_depends += " \\\n ";
		m_depends += _fileName;
	}

	bool run(const char* _input)
	{
		m_fgetsPos = 0;

		m_preprocessed.clear();
		m_input = m_default;
		m_input += "\n\n";

		size_t len = strlen(_input)+1;
		char* temp = new char[len];
		bx::eolLF(temp, len, _input);
		m_input += temp;
		delete [] temp;

		fppTag* tagptr = m_tagptr;

		tagptr->tag = FPPTAG_END;
		tagptr->data = 0;
		tagptr++;

		int result = fppPreProcess(m_tags);

		return 0 == result;
	}

	char* fgets(char* _buffer, int _size)
	{
		int ii = 0;
		for (char ch = m_input[m_fgetsPos]; m_fgetsPos < m_input.size() && ii < _size-1; ch = m_input[++m_fgetsPos])
		{
			_buffer[ii++] = ch;

			if (ch == '\n' || ii == _size)
			{
				_buffer[ii] = '\0';
				m_fgetsPos++;
				return _buffer;
			}
		}

		return NULL;
	}

	static void fppDepends(char* _fileName, void* _userData)
	{
		Preprocessor* thisClass = (Preprocessor*)_userData;
		thisClass->addDependency(_fileName);
	}

	static char* fppInput(char* _buffer, int _size, void* _userData)
	{
		Preprocessor* thisClass = (Preprocessor*)_userData;
		return thisClass->fgets(_buffer, _size);
	}

	static void fppOutput(int _ch, void* _userData)
	{
		Preprocessor* thisClass = (Preprocessor*)_userData;
		thisClass->m_preprocessed += _ch;
	}

	static void fppError(void* /*_userData*/, char* _format, va_list _vargs)
	{
		vfprintf(stderr, _format, _vargs);
	}

	char* scratch(const char* _str)
	{
		char* result = &m_scratch[m_scratchPos];
		strcpy(result, _str);
		m_scratchPos += (uint32_t)strlen(_str)+1;

		return result;
	}

	fppTag m_tags[MAX_TAGS];
	fppTag* m_tagptr;

	std::string m_depends;
	std::string m_default;
	std::string m_input;
	std::string m_preprocessed;
	char m_scratch[16<<10];
	uint32_t m_scratchPos;
	uint32_t m_fgetsPos;
};

typedef std::vector<std::string> InOut;

uint32_t parseInOut(InOut& _inout, const char* _str, const char* _eol)
{
	uint32_t hash = 0;
	_str = bx::strws(_str);

	if (_str < _eol)
	{
		const char* delim;
		do
		{
			delim = strpbrk(_str, " ,");
			if (NULL != delim)
			{
				delim = delim > _eol ? _eol : delim;
				std::string token;
				token.assign(_str, delim-_str);
				_inout.push_back(token);
				_str = bx::strws(delim + 1);
			}
		}
		while (delim < _eol && _str < _eol && NULL != delim);

		std::sort(_inout.begin(), _inout.end() );

		bx::HashMurmur2A murmur;
		murmur.begin();
		for (InOut::const_iterator it = _inout.begin(), itEnd = _inout.end(); it != itEnd; ++it)
		{
			murmur.add(it->c_str(), (uint32_t)it->size() );
		}
		hash = murmur.end();
	}

	return hash;
}

void addFragData(Preprocessor& _preprocessor, char* _data, uint32_t _idx, bool _comma)
{
	char find[32];
	bx::snprintf(find, sizeof(find), "gl_FragData[%d]", _idx);

	char replace[32];
	bx::snprintf(replace, sizeof(replace), "gl_FragData_%d_", _idx);

	strreplace(_data, find, replace);

	_preprocessor.writef(
		" \\\n\t%sout vec4 gl_FragData_%d_ : SV_TARGET%d"
		, _comma ? ", " : "  "
		, _idx
		, _idx
		);
}

void voidFragData(char* _data, uint32_t _idx)
{
	char find[32];
	bx::snprintf(find, sizeof(find), "gl_FragData[%d]", _idx);

	strreplace(_data, find, "bgfx_VoidFrag");
}

// c - compute
// d - domain
// f - fragment
// g - geometry
// h - hull
// v - vertex
//
// OpenGL #version Features Direct3D Features Shader Model
// 2.1    120      vf       9.0      vf       2.0
// 3.0    130
// 3.1    140
// 3.2    150      vgf
// 3.3    330               10.0     vgf      4.0
// 4.0    400      vhdgf
// 4.1    410
// 4.2    420               11.0     vhdgf+c  5.0
// 4.3    430      vhdgf+c
// 4.4    440

static void help (const char* errmsg) {
	fprintf(stderr, "%s\n", errmsg);
}

int compileShader(bx::CommandLine& _cmdLine, bx::ReaderSeekerI* _reader, bx::WriterI* _writer)
{
	g_verbose = _cmdLine.hasArg("verbose");

	const char* filePath = _cmdLine.findOption('f');
	if (NULL == filePath)
	{
		help("Shader file name must be specified.");
		return EXIT_FAILURE;
	}

	const char* outFilePath = _cmdLine.findOption('o');

	const char* type = _cmdLine.findOption('\0', "type");
	if (NULL == type)
	{
		help("Must specify shader type.");
		return EXIT_FAILURE;
	}

	const char* platform = _cmdLine.findOption('\0', "platform");
	if (NULL == platform)
	{
		help("Must specify platform.");
		return EXIT_FAILURE;
	}

	bool raw = _cmdLine.hasArg('\0', "raw");

	uint32_t glsl  = 0;
	uint32_t essl  = 0;
	uint32_t hlsl  = 2;
	uint32_t d3d   = 11;
	uint32_t metal = 0;
	const char* profile = _cmdLine.findOption('p', "profile");
	if (NULL != profile)
	{
		if (0 == strncmp(&profile[1], "s_4_0_level", 11) )
		{
			hlsl = 2;
		}
		else if (0 == strncmp(&profile[1], "s_3", 3) )
		{
			hlsl = 3;
			d3d  = 9;
		}
		else if (0 == strncmp(&profile[1], "s_4", 3) )
		{
			hlsl = 4;
		}
		else if (0 == strncmp(&profile[1], "s_5", 3) )
		{
			hlsl = 5;
		}
		else if (0 == strcmp(profile, "metal") )
		{
			metal = 1;
		}
		else
		{
			glsl = atoi(profile);
		}
	}
	else
	{
		essl = 2;
	}

	bool depends = _cmdLine.hasArg("depends");
	bool preprocessOnly = _cmdLine.hasArg("preprocess");
	const char* includeDir = _cmdLine.findOption('i');

	Preprocessor preprocessor(filePath, 0 != essl, includeDir);

	std::string dir;
	{
		const char* base = bx::baseName(filePath);

		if (base != filePath)
		{
			dir.assign(filePath, base-filePath);
			preprocessor.addInclude(dir.c_str() );
		}
	}

	preprocessor.setDefaultDefine("BX_PLATFORM_ANDROID");
	preprocessor.setDefaultDefine("BX_PLATFORM_EMSCRIPTEN");
	preprocessor.setDefaultDefine("BX_PLATFORM_IOS");
	preprocessor.setDefaultDefine("BX_PLATFORM_LINUX");
	preprocessor.setDefaultDefine("BX_PLATFORM_NACL");
	preprocessor.setDefaultDefine("BX_PLATFORM_OSX");
	preprocessor.setDefaultDefine("BX_PLATFORM_WINDOWS");
	preprocessor.setDefaultDefine("BX_PLATFORM_XBOX360");
//	preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_ESSL");
	preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_GLSL");
	preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_HLSL");
	preprocessor.setDefaultDefine("BGFX_SHADER_LANGUAGE_METAL");
	preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_COMPUTE");
	preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_FRAGMENT");
	preprocessor.setDefaultDefine("BGFX_SHADER_TYPE_VERTEX");

	char glslDefine[128];
	bx::snprintf(glslDefine, BX_COUNTOF(glslDefine), "BGFX_SHADER_LANGUAGE_GLSL=%d", essl ? 1 : glsl);

	if (0 == bx::strincmp(platform, "android") )
	{
		preprocessor.setDefine("BX_PLATFORM_ANDROID=1");
		preprocessor.setDefine("BGFX_SHADER_LANGUAGE_GLSL=1");
	}
	else if (0 == bx::strincmp(platform, "asm.js") )
	{
		preprocessor.setDefine("BX_PLATFORM_EMSCRIPTEN=1");
		preprocessor.setDefine("BGFX_SHADER_LANGUAGE_GLSL=1");
	}
	else if (0 == bx::strincmp(platform, "ios") )
	{
		preprocessor.setDefine("BX_PLATFORM_IOS=1");
		preprocessor.setDefine("BGFX_SHADER_LANGUAGE_GLSL=1");
	}
	else if (0 == bx::strincmp(platform, "linux") )
	{
		preprocessor.setDefine("BX_PLATFORM_LINUX=1");
		preprocessor.setDefine(glslDefine);
	}
	else if (0 == bx::strincmp(platform, "nacl") )
	{
		preprocessor.setDefine("BX_PLATFORM_NACL=1");
		preprocessor.setDefine("BGFX_SHADER_LANGUAGE_GLSL=1");
	}
	else if (0 == bx::strincmp(platform, "osx") )
	{
		preprocessor.setDefine("BX_PLATFORM_OSX=1");
		preprocessor.setDefine(glslDefine);
		char temp[256];
		bx::snprintf(temp, sizeof(temp), "BGFX_SHADER_LANGUAGE_METAL=%d", metal);
		preprocessor.setDefine(temp);
	}
	else if (0 == bx::strincmp(platform, "windows") )
	{
		preprocessor.setDefine("BX_PLATFORM_WINDOWS=1");
		char temp[256];
		bx::snprintf(temp, sizeof(temp), "BGFX_SHADER_LANGUAGE_HLSL=%d", hlsl);
		preprocessor.setDefine(temp);
	}
	else if (0 == bx::strincmp(platform, "xbox360") )
	{
		preprocessor.setDefine("BX_PLATFORM_XBOX360=1");
		preprocessor.setDefine("BGFX_SHADER_LANGUAGE_HLSL=3");
	}
	else
	{
		fprintf(stderr, "Unknown platform %s?!", platform);
		return EXIT_FAILURE;
	}

	preprocessor.setDefine("M_PI=3.1415926535897932384626433832795");

	char shaderType = tolower(type[0]);
	switch (shaderType)
	{
	case 'c':
		preprocessor.setDefine("BGFX_SHADER_TYPE_COMPUTE=1");
		break;

	case 'f':
		preprocessor.setDefine("BGFX_SHADER_TYPE_FRAGMENT=1");
		break;

	case 'v':
		preprocessor.setDefine("BGFX_SHADER_TYPE_VERTEX=1");
		break;

	default:
		fprintf(stderr, "Unknown type: %s?!", type);
		return EXIT_FAILURE;
	}

	bool compiled = false;

	{
		VaryingMap varyingMap;

		std::string defaultVarying = dir + "varying.def.sc";
		const char* varyingdef = _cmdLine.findOption("varyingdef", defaultVarying.c_str() );
		File attribdef(varyingdef);
		const char* parse = attribdef.getData();
		if (NULL != parse
		&&  *parse != '\0')
		{
			preprocessor.addDependency(varyingdef);
		}
		else
		{
			fprintf(stderr, "ERROR: Failed to parse varying def file: \"%s\" No input/output semantics will be generated in the code!\n", varyingdef);
		}

		while (NULL != parse
		   &&  *parse != '\0')
		{
			parse = bx::strws(parse);
			const char* eol = strchr(parse, ';');
			if (NULL == eol)
			{
				eol = bx::streol(parse);
			}

			if (NULL != eol)
			{
				const char* precision = NULL;
				const char* interpolation = NULL;
				const char* typen = parse;

				if (0 == strncmp(typen, "lowp", 4)
				||  0 == strncmp(typen, "mediump", 7)
				||  0 == strncmp(typen, "highp", 5) )
				{
					precision = typen;
					typen = parse = bx::strws(bx::strword(parse) );
				}

				if (0 == strncmp(typen, "flat", 4)
				||  0 == strncmp(typen, "smooth", 6)
				||  0 == strncmp(typen, "noperspective", 13) )
				{
					interpolation = typen;
					typen = parse = bx::strws(bx::strword(parse) );
				}

				const char* name      = parse = bx::strws(bx::strword(parse) );
				const char* column    = parse = bx::strws(bx::strword(parse) );
				const char* semantics = parse = bx::strws((*parse == ':' ? ++parse : parse));
				const char* assign    = parse = bx::strws(bx::strword(parse) );
				const char* init      = parse = bx::strws((*parse == '=' ? ++parse : parse));

				if (typen < eol
				&&  name < eol
				&&  column < eol
				&&  ':' == *column
				&&  semantics < eol)
				{
					Varying var;
					if (NULL != precision)
					{
						var.m_precision.assign(precision, bx::strword(precision)-precision);
					}

					if (NULL != interpolation)
					{
						var.m_interpolation.assign(interpolation, bx::strword(interpolation)-interpolation);
					}

					var.m_type.assign(typen, bx::strword(typen)-typen);
					var.m_name.assign(name, bx::strword(name)-name);
					var.m_semantics.assign(semantics, bx::strword(semantics)-semantics);

					if (d3d == 9
					&&  var.m_semantics == "BITANGENT")
					{
						var.m_semantics = "BINORMAL";
					}

					if (assign < eol
					&&  '=' == *assign
					&&  init < eol)
					{
						var.m_init.assign(init, eol-init);
					}

					varyingMap.insert(std::make_pair(var.m_name, var) );
				}

				parse = bx::strws(bx::strnl(eol) );
			}
		}

		InOut shaderInputs;
		InOut shaderOutputs;
		uint32_t inputHash = 0;
		uint32_t outputHash = 0;

		char* data;
		char* input;
		{
			const size_t padding = 1024;
			long int r_offset = _reader->seek();
			_reader->seek(0, bx::Whence::End);
			uint32_t size = (uint32_t)_reader->seek(0, bx::Whence::End);
			_reader->seek(r_offset, bx::Whence::Begin);

			bx::Error err;
			data = new char[size+padding+1];
			_reader->read(data, size - r_offset, &err);
			// Compiler generates "error X3000: syntax error: unexpected end of file"
			// if input doesn't have empty line at EOF.
			data[size] = '\n';
			memset(&data[size+1], 0, padding);

			input = const_cast<char*>(bx::strws(data) );
			while (input[0] == '$')
			{
				const char* str = bx::strws(input+1);
				const char* eol = bx::streol(str);
				const char* nl  = bx::strnl(eol);
				input = const_cast<char*>(nl);

				if (0 == strncmp(str, "input", 5) )
				{
					str += 5;
					const char* comment = strstr(str, "//");
					eol = NULL != comment && comment < eol ? comment : eol;
					inputHash = parseInOut(shaderInputs, str, eol);
				}
				else if (0 == strncmp(str, "output", 6) )
				{
					str += 6;
					const char* comment = strstr(str, "//");
					eol = NULL != comment && comment < eol ? comment : eol;
					outputHash = parseInOut(shaderOutputs, str, eol);
				}
				else if (0 == strncmp(str, "raw", 3) )
				{
					raw = true;
					str += 3;
				}

				input = const_cast<char*>(bx::strws(input) );
			}

			if (!raw)
			{
				// To avoid commented code being recognized as used feature,
				// first preprocess pass is used to strip all comments before
				// substituting code.
				preprocessor.run(input);
				delete [] data;

				size = (uint32_t)preprocessor.m_preprocessed.size();
				data = new char[size+padding+1];
				memcpy(data, preprocessor.m_preprocessed.c_str(), size);
				memset(&data[size], 0, padding+1);
				input = data;
			}
		}

		if (raw)
		{
			if ('f' == shaderType)
			{
				bx::write(_writer, BGFX_CHUNK_MAGIC_FSH);
				bx::write(_writer, inputHash);
			}
			else if ('v' == shaderType)
			{
				bx::write(_writer, BGFX_CHUNK_MAGIC_VSH);
				bx::write(_writer, outputHash);
			}
			else
			{
				bx::write(_writer, BGFX_CHUNK_MAGIC_CSH);
				bx::write(_writer, outputHash);
			}

			if (0 != glsl)
			{
				bx::write(_writer, uint16_t(0) );

				uint32_t shaderSize = (uint32_t)strlen(input);
				bx::write(_writer, shaderSize);
				bx::write(_writer, input, shaderSize);
				bx::write(_writer, uint8_t(0) );

				compiled = true;
			}
			else
			{
				compiled = compileHLSLShader(_cmdLine, d3d, input, _writer);
			}
		}
		else if ('c' == shaderType) // Compute
		{
			char* entry = strstr(input, "void main()");
			if (NULL == entry)
			{
				fprintf(stderr, "Shader entry point 'void main()' is not found.\n");
			}
			else
			{
				if (0 != glsl
				||  0 != essl
				||  0 != metal)
				{
				}
				else
				{
					preprocessor.writef(
						"#define lowp\n"
						"#define mediump\n"
						"#define highp\n"
						"#define ivec2 int2\n"
						"#define ivec3 int3\n"
						"#define ivec4 int4\n"
						"#define uvec2 uint2\n"
						"#define uvec3 uint3\n"
						"#define uvec4 uint4\n"
						"#define vec2 float2\n"
						"#define vec3 float3\n"
						"#define vec4 float4\n"
						"#define mat2 float2x2\n"
						"#define mat3 float3x3\n"
						"#define mat4 float4x4\n"
						);

					entry[4] = '_';

					preprocessor.writef("#define void_main()");
					preprocessor.writef(" \\\n\tvoid main(");

					uint32_t arg = 0;

					const bool hasLocalInvocationID    = NULL != strstr(input, "gl_LocalInvocationID");
					const bool hasLocalInvocationIndex = NULL != strstr(input, "gl_LocalInvocationIndex");
					const bool hasGlobalInvocationID   = NULL != strstr(input, "gl_GlobalInvocationID");
					const bool hasWorkGroupID          = NULL != strstr(input, "gl_WorkGroupID");

					if (hasLocalInvocationID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_LocalInvocationID : SV_GroupThreadID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasLocalInvocationIndex)
					{
						preprocessor.writef(
							" \\\n\t%sint gl_LocalInvocationIndex : SV_GroupIndex"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasGlobalInvocationID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_GlobalInvocationID : SV_DispatchThreadID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					if (hasWorkGroupID)
					{
						preprocessor.writef(
							" \\\n\t%sint3 gl_WorkGroupID : SV_GroupID"
							, arg++ > 0 ? ", " : "  "
							);
					}

					preprocessor.writef(
						" \\\n\t)\n"
						);
				}

				if (preprocessor.run(input) )
				{
					BX_TRACE("Input file: %s", filePath);
					BX_TRACE("Output file: %s", outFilePath != NULL ? outFilePath : "NULL");

					if (preprocessOnly)
					{
						bx::Error err;
						_writer->write(preprocessor.m_preprocessed.c_str(), (int32_t)preprocessor.m_preprocessed.size(), &err);

						return EXIT_SUCCESS;
					}

					{
						bx::write(_writer, BGFX_CHUNK_MAGIC_CSH);
						bx::write(_writer, outputHash);

						if (0 != glsl
						||  0 != essl)
						{
							std::string code;

							if (essl)
							{
								bx::stringPrintf(code, "#version 310 es\n");
							}
							else
							{
								bx::stringPrintf(code, "#version %d\n", glsl == 0 ? 430 : glsl);
							}

							code += preprocessor.m_preprocessed;
#if 1
							bx::write(_writer, uint16_t(0) );

							uint32_t shaderSize = (uint32_t)code.size();
							bx::write(_writer, shaderSize);
							bx::write(_writer, code.c_str(), shaderSize);
							bx::write(_writer, uint8_t(0) );

							compiled = true;
#else
							compiled = compileGLSLShader(_cmdLine, essl, code, _writer);
#endif // 0
						}
						else
						{
							compiled = compileHLSLShader(_cmdLine, d3d, preprocessor.m_preprocessed, _writer);
						}
					}

					if (compiled && depends)
					{
						if (outFilePath == NULL) 
						{
							fprintf(stderr, "Cannot create depends file: no output file specified!\n");
							return EXIT_FAILURE;
						}
						else
						{
							std::string ofp = outFilePath;
							ofp += ".d";
							bx::CrtFileWriter writer;
							bx::Error err;
							if (0 == writer.open(ofp.c_str(), false, &err) )
							{
								writef(&writer, "%s : %s\n", outFilePath, preprocessor.m_depends.c_str() );
								writer.close();
							}
						}
					}
				}
			}
		}
		else // Vertex/Fragment
		{
			char* entry = strstr(input, "void main()");
			if (NULL == entry)
			{
				fprintf(stderr, "Shader entry point 'void main()' is not found.\n");
			}
			else
			{
				if (0 != glsl
				||  0 != essl
				||  0 != metal)
				{
					if (120 == glsl
					||  0   != essl)
					{
						preprocessor.writef(
							"#define ivec2 vec2\n"
							"#define ivec3 vec3\n"
							"#define ivec4 vec4\n"
							);
					}

					if (0 == essl)
					{
						// bgfx shadow2D/Proj behave like EXT_shadow_samplers
						// not as GLSL language 1.2 specs shadow2D/Proj.
						preprocessor.writef(
							"#define shadow2D(_sampler, _coord) bgfxShadow2D(_sampler, _coord).x\n"
							"#define shadow2DProj(_sampler, _coord) bgfxShadow2DProj(_sampler, _coord).x\n"
							);
					}

					for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
					{
						VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
						if (varyingIt != varyingMap.end() )
						{
							const Varying& var = varyingIt->second;
							const char* name = var.m_name.c_str();

							if (0 == strncmp(name, "a_", 2)
							||  0 == strncmp(name, "i_", 2) )
							{
								preprocessor.writef("attribute %s %s %s %s;\n"
										, var.m_precision.c_str()
										, var.m_interpolation.c_str()
										, var.m_type.c_str()
										, name
										);
							}
							else
							{
								preprocessor.writef("%s varying %s %s %s;\n"
										, var.m_interpolation.c_str()
										, var.m_precision.c_str()
										, var.m_type.c_str()
										, name
										);
							}
						}
					}

					for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
					{
						VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
						if (varyingIt != varyingMap.end() )
						{
							const Varying& var = varyingIt->second;
							preprocessor.writef("%s varying %s %s;\n"
								, var.m_interpolation.c_str()
								, var.m_type.c_str()
								, var.m_name.c_str()
								);
						}
					}
				}
				else
				{
					preprocessor.writef(
						"#define lowp\n"
						"#define mediump\n"
						"#define highp\n"
						"#define ivec2 int2\n"
						"#define ivec3 int3\n"
						"#define ivec4 int4\n"
						"#define uvec2 uint2\n"
						"#define uvec3 uint3\n"
						"#define uvec4 uint4\n"
						"#define vec2 float2\n"
						"#define vec3 float3\n"
						"#define vec4 float4\n"
						"#define mat2 float2x2\n"
						"#define mat3 float3x3\n"
						"#define mat4 float4x4\n"
						);

					if (hlsl < 4)
					{
						preprocessor.writef(
							"#define flat\n"
							"#define smooth\n"
							"#define noperspective\n"
							);
					}

					entry[4] = '_';

					if ('f' == shaderType)
					{
						const char* brace = strstr(entry, "{");
						if (NULL != brace)
						{
							strins(const_cast<char*>(brace+1), "\nvec4 bgfx_VoidFrag;\n");
						}

						const bool hasFragCoord   = NULL != strstr(input, "gl_FragCoord") || hlsl > 3 || hlsl == 2;
						const bool hasFragDepth   = NULL != strstr(input, "gl_FragDepth");
						const bool hasFrontFacing = NULL != strstr(input, "gl_FrontFacing");
						const bool hasPrimitiveId = NULL != strstr(input, "gl_PrimitiveID");

						bool hasFragData[8] = {};
						uint32_t numFragData = 0;
						for (uint32_t ii = 0; ii < BX_COUNTOF(hasFragData); ++ii)
						{
							char temp[32];
							bx::snprintf(temp, BX_COUNTOF(temp), "gl_FragData[%d]", ii);
							hasFragData[ii] = NULL != strstr(input, temp);
							numFragData += hasFragData[ii];
						}

						if (0 == numFragData)
						{
							// GL errors when both gl_FragColor and gl_FragData is used.
							// This will trigger the same error with HLSL compiler too.
							preprocessor.writef("#define gl_FragColor gl_FragData_0_\n");
						}

						preprocessor.writef("#define void_main()");
						preprocessor.writef(" \\\n\tvoid main(");

						uint32_t arg = 0;

						if (hasFragCoord)
						{
							preprocessor.writef(" \\\n\tvec4 gl_FragCoord : SV_POSITION");
							++arg;
						}

						for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(" \\\n\t%s%s %s %s : %s"
									, arg++ > 0 ? ", " : "  "
									, interpolationDx11(var.m_interpolation.c_str() )
									, var.m_type.c_str()
									, var.m_name.c_str()
									, var.m_semantics.c_str()
									);
							}
						}

						addFragData(preprocessor, input, 0, arg++ > 0);

						const uint32_t maxRT = d3d > 9 ? BX_COUNTOF(hasFragData) : 4;

						for (uint32_t ii = 1; ii < BX_COUNTOF(hasFragData); ++ii)
						{
							if (ii < maxRT)
							{
								if (hasFragData[ii])
								{
									addFragData(preprocessor, input, ii, arg++ > 0);
								}
							}
							else
							{
								voidFragData(input, ii);
							}
						}

						if (hasFragDepth)
						{
							preprocessor.writef(
								" \\\n\t%sout float gl_FragDepth : SV_DEPTH"
								, arg++ > 0 ? ", " : "  "
								);
						}

						if (hasFrontFacing
						&&  hlsl >= 3)
						{
							preprocessor.writef(
								" \\\n\t%sfloat __vface : VFACE"
								, arg++ > 0 ? ", " : "  "
								);
						}

						if (hasPrimitiveId)
						{
							if (d3d > 9)
							{
								preprocessor.writef(
									" \\\n\t%suint gl_PrimitiveID : SV_PrimitiveID"
									, arg++ > 0 ? ", " : "  "
									);
							}
							else
							{
								fprintf(stderr, "PrimitiveID builtin is not supported by this D3D9 HLSL.\n");
								return EXIT_FAILURE;
							}
						}

						preprocessor.writef(
							" \\\n\t)\n"
							);

						if (hasFrontFacing)
						{
							if (hlsl >= 3)
							{
								preprocessor.writef(
									"#define gl_FrontFacing (__vface <= 0.0)\n"
									);
							}
							else
							{
								preprocessor.writef(
									"#define gl_FrontFacing false\n"
									);
							}
						}
					}
					else if ('v' == shaderType)
					{
						const char* brace = strstr(entry, "{");
						if (NULL != brace)
						{
							const char* end = bx::strmb(brace, '{', '}');
							if (NULL != end)
							{
								strins(const_cast<char*>(end), "__RETURN__;\n");
							}
						}

						preprocessor.writef(
							"struct Output\n"
							"{\n"
							"\tvec4 gl_Position : SV_POSITION;\n"
							"#define gl_Position _varying_.gl_Position\n"
							);
						for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef("\t%s %s : %s;\n", var.m_type.c_str(), var.m_name.c_str(), var.m_semantics.c_str() );
								preprocessor.writef("#define %s _varying_.%s\n", var.m_name.c_str(), var.m_name.c_str() );
							}
						}
						preprocessor.writef(
							"};\n"
							);

						preprocessor.writef("#define void_main() \\\n");
						preprocessor.writef("Output main(");
						bool first = true;
						for (InOut::const_iterator it = shaderInputs.begin(), itEnd = shaderInputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef("%s%s %s : %s\\\n", first ? "" : "\t, ", var.m_type.c_str(), var.m_name.c_str(), var.m_semantics.c_str() );
								first = false;
							}
						}
						preprocessor.writef(
							") \\\n"
							"{ \\\n"
							"\tOutput _varying_;"
							);

						for (InOut::const_iterator it = shaderOutputs.begin(), itEnd = shaderOutputs.end(); it != itEnd; ++it)
						{
							VaryingMap::const_iterator varyingIt = varyingMap.find(*it);
							if (varyingIt != varyingMap.end() )
							{
								const Varying& var = varyingIt->second;
								preprocessor.writef(" \\\n\t%s", var.m_name.c_str() );
								if (!var.m_init.empty() )
								{
									preprocessor.writef(" = %s", var.m_init.c_str() );
								}
								preprocessor.writef(";");
							}
						}

						preprocessor.writef(
							"\n#define __RETURN__ \\\n"
							"\t} \\\n"
							"\treturn _varying_"
							);
					}
				}

				if (preprocessor.run(input) )
				{
					BX_TRACE("Input file: %s", filePath);
					BX_TRACE("Output file: %s", outFilePath != NULL ? outFilePath : "NULL");

					if (preprocessOnly)
					{
						if (0 != glsl)
						{
							if (NULL == profile)
							{
								writef(_writer
									, "#ifdef GL_ES\n"
									  "precision highp float;\n"
									  "#endif // GL_ES\n\n"
									);
							}
						}
						bx::Error err;
						_writer->write(preprocessor.m_preprocessed.c_str(), (int32_t)preprocessor.m_preprocessed.size(), &err);

						return EXIT_SUCCESS;
					}

					{
						if ('f' == shaderType)
						{
							bx::write(_writer, BGFX_CHUNK_MAGIC_FSH);
							bx::write(_writer, inputHash);
						}
						else if ('v' == shaderType)
						{
							bx::write(_writer, BGFX_CHUNK_MAGIC_VSH);
							bx::write(_writer, outputHash);
						}
						else
						{
							bx::write(_writer, BGFX_CHUNK_MAGIC_CSH);
							bx::write(_writer, outputHash);
						}

						if (0 != glsl
						||  0 != essl
						||  0 != metal)
						{
							std::string code;

							bool hasTextureLod = NULL != bx::findIdentifierMatch(input, s_ARB_shader_texture_lod /*EXT_shader_texture_lod*/);

							if (0 == essl)
							{
								const bool need130 = 120 == glsl
									&& bx::findIdentifierMatch(input, s_130)
									;

								if (0 != metal)
								{
									bx::stringPrintf(code, "#version 120\n");
								}
								else
								{
									bx::stringPrintf(code, "#version %s\n", need130 ? "130" : profile);
								}

								bx::stringPrintf(code
									, "#define bgfxShadow2D shadow2D\n"
									  "#define bgfxShadow2DProj shadow2DProj\n"
									);

								if (hasTextureLod
								&&  130 > glsl)
								{
									bx::stringPrintf(code
										, "#extension GL_ARB_shader_texture_lod : enable\n"
										);
								}
							}
							else
							{
								// Pretend that all extensions are available.
								// This will be stripped later.
								if (hasTextureLod)
								{
									bx::stringPrintf(code
										, "#extension GL_EXT_shader_texture_lod : enable\n"
										  "#define texture2DLod texture2DLodEXT\n"
										  "#define texture2DProjLod texture2DProjLodEXT\n"
										  "#define textureCubeLod textureCubeLodEXT\n"
//										  "#define texture2DGrad texture2DGradEXT\n"
//										  "#define texture2DProjGrad texture2DProjGradEXT\n"
//										  "#define textureCubeGrad textureCubeGradEXT\n"
										);
								}

								if (NULL != bx::findIdentifierMatch(input, s_OES_standard_derivatives) )
								{
									bx::stringPrintf(code, "#extension GL_OES_standard_derivatives : enable\n");
								}

								if (NULL != bx::findIdentifierMatch(input, s_OES_texture_3D) )
								{
									bx::stringPrintf(code, "#extension GL_OES_texture_3D : enable\n");
								}

								if (NULL != bx::findIdentifierMatch(input, s_EXT_shadow_samplers) )
								{
									bx::stringPrintf(code
										, "#extension GL_EXT_shadow_samplers : enable\n"
										  "#define shadow2D shadow2DEXT\n"
										  "#define shadow2DProj shadow2DProjEXT\n"
										);
								}

								if (NULL != bx::findIdentifierMatch(input, "gl_FragDepth") )
								{
									bx::stringPrintf(code
										, "#extension GL_EXT_frag_depth : enable\n"
										  "#define gl_FragDepth gl_FragDepthEXT\n"
										);
								}
							}

							code += preprocessor.m_preprocessed;
							compiled = compileGLSLShader(_cmdLine
									, metal ? BX_MAKEFOURCC('M', 'T', 'L', 0) : essl
									, code
									, _writer
									);
						}
						else
						{
							compiled = compileHLSLShader(_cmdLine
									, d3d
									, preprocessor.m_preprocessed
									, _writer
									);
						}
					}

					if (compiled && depends)
					{
						if (outFilePath == NULL) 
						{
							fprintf(stderr, "Cannot create depends file: no output file specified!\n");
							return EXIT_FAILURE;
						}
						else
						{
							std::string ofp = outFilePath;
							ofp += ".d";
							bx::CrtFileWriter writer;
							bx::Error err;
 							if (0 == writer.open(ofp.c_str(), false, &err) )
							{
								writef(&writer, "%s : %s\n", outFilePath, preprocessor.m_depends.c_str() );
								writer.close();
							}							
						}
					}
				}
			}
		}

		delete [] data;
	}

	if (compiled)
	{
		return EXIT_SUCCESS;
	}

	if (NULL != outFilePath)
	{
		remove(outFilePath);
	}

	fprintf(stderr, "Failed to build shader.\n");
	return EXIT_FAILURE;
}