/*
 * Copyright 2011-2013 Blender Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "device/device.h"

#include "render/graph.h"
#include "render/light.h"
#include "render/osl.h"
#include "render/scene.h"
#include "render/shader.h"
#include "render/nodes.h"

#ifdef WITH_OSL

#include "kernel/osl/osl_globals.h"
#include "kernel/osl/osl_services.h"
#include "kernel/osl/osl_shader.h"

#include "util/util_foreach.h"
#include "util/util_logging.h"
#include "util/util_md5.h"
#include "util/util_path.h"
#include "util/util_progress.h"

#endif

CCL_NAMESPACE_BEGIN

#ifdef WITH_OSL

/* Shared Texture and Shading System */

OSL::TextureSystem *OSLShaderManager::ts_shared = NULL;
int OSLShaderManager::ts_shared_users = 0;
thread_mutex OSLShaderManager::ts_shared_mutex;

OSL::ShadingSystem *OSLShaderManager::ss_shared = NULL;
OSLRenderServices *OSLShaderManager::services_shared = NULL;
int OSLShaderManager::ss_shared_users = 0;
thread_mutex OSLShaderManager::ss_shared_mutex;
thread_mutex OSLShaderManager::ss_mutex;

/* Shader Manager */

OSLShaderManager::OSLShaderManager()
{
	texture_system_init();
	shading_system_init();
}

OSLShaderManager::~OSLShaderManager()
{
	shading_system_free();
	texture_system_free();
}

void OSLShaderManager::reset(Scene * /*scene*/)
{
	shading_system_free();
	shading_system_init();
}

void OSLShaderManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
{
	if(!need_update)
		return;

	VLOG(1) << "Total " << scene->shaders.size() << " shaders.";

	device_free(device, dscene, scene);

	/* determine which shaders are in use */
	device_update_shaders_used(scene);

	/* create shaders */
	OSLGlobals *og = (OSLGlobals*)device->osl_memory();

	foreach(Shader *shader, scene->shaders) {
		assert(shader->graph);

		if(progress.get_cancel()) return;

		/* we can only compile one shader at the time as the OSL ShadingSytem
		 * has a single state, but we put the lock here so different renders can
		 * compile shaders alternating */
		thread_scoped_lock lock(ss_mutex);

		OSLCompiler compiler((void*)this, (void*)ss, scene->image_manager);
		compiler.background = (shader == scene->default_background);
		compiler.compile(scene, og, shader);

		if(shader->use_mis && shader->has_surface_emission)
			scene->light_manager->need_update = true;
	}

	/* setup shader engine */
	og->ss = ss;
	og->ts = ts;
	og->services = services;

	int background_id = scene->shader_manager->get_shader_id(scene->default_background);
	og->background_state = og->surface_state[background_id & SHADER_MASK];
	og->use = true;

	foreach(Shader *shader, scene->shaders)
		shader->need_update = false;

	need_update = false;
	
	/* set texture system */
	scene->image_manager->set_osl_texture_system((void*)ts);

	device_update_common(device, dscene, scene, progress);

	{
		/* Perform greedyjit optimization.
		 *
		 * This might waste time on optimizing gorups which are never actually
		 * used, but this prevents OSL from allocating data on TLS at render
		 * time.
		 *
		 * This is much better for us because this way we aren't required to
		 * stop task scheduler threads to make sure all TLS is clean and don't
		 * have issues with TLS data free accessing freed memory if task scheduler
		 * is being freed after the Session is freed.
		 */
		thread_scoped_lock lock(ss_shared_mutex);
		ss->optimize_all_groups();
	}
}

void OSLShaderManager::device_free(Device *device, DeviceScene *dscene, Scene *scene)
{
	OSLGlobals *og = (OSLGlobals*)device->osl_memory();

	device_free_common(device, dscene, scene);

	/* clear shader engine */
	og->use = false;
	og->ss = NULL;
	og->ts = NULL;

	og->surface_state.clear();
	og->volume_state.clear();
	og->displacement_state.clear();
	og->background_state.reset();
}

void OSLShaderManager::texture_system_init()
{
	/* create texture system, shared between different renders to reduce memory usage */
	thread_scoped_lock lock(ts_shared_mutex);

	if(ts_shared_users == 0) {
		ts_shared = TextureSystem::create(true);

		ts_shared->attribute("automip",  1);
		ts_shared->attribute("autotile", 64);
		ts_shared->attribute("gray_to_rgb", 1);

		/* effectively unlimited for now, until we support proper mipmap lookups */
		ts_shared->attribute("max_memory_MB", 16384);
	}

	ts = ts_shared;
	ts_shared_users++;
}

void OSLShaderManager::texture_system_free()
{
	/* shared texture system decrease users and destroy if no longer used */
	thread_scoped_lock lock(ts_shared_mutex);
	ts_shared_users--;

	if(ts_shared_users == 0) {
		ts_shared->invalidate_all(true);
		OSL::TextureSystem::destroy(ts_shared);
		ts_shared = NULL;
	}

	ts = NULL;
}

void OSLShaderManager::shading_system_init()
{
	/* create shading system, shared between different renders to reduce memory usage */
	thread_scoped_lock lock(ss_shared_mutex);

	if(ss_shared_users == 0) {
		services_shared = new OSLRenderServices();

		string shader_path = path_get("shader");
#ifdef _WIN32
		/* Annoying thing, Cycles stores paths in UTF-8 codepage, so it can
		 * operate with file paths with any character. This requires to use wide
		 * char functions, but OSL uses old fashioned ANSI functions which means:
		 *
		 * - We have to convert our paths to ANSI before passing to OSL
		 * - OSL can't be used when there's a multi-byte character in the path
		 *   to the shaders folder.
		 */
		shader_path = string_to_ansi(shader_path);
#endif

		ss_shared = new OSL::ShadingSystem(services_shared, ts_shared, &errhandler);
		ss_shared->attribute("lockgeom", 1);
		ss_shared->attribute("commonspace", "world");
		ss_shared->attribute("searchpath:shader", shader_path);
		ss_shared->attribute("greedyjit", 1);

		VLOG(1) << "Using shader search path: " << shader_path;

		/* our own ray types */
		static const char *raytypes[] = {
			"camera",			/* PATH_RAY_CAMERA */
			"reflection",		/* PATH_RAY_REFLECT */
			"refraction",		/* PATH_RAY_TRANSMIT */
			"diffuse",			/* PATH_RAY_DIFFUSE */
			"glossy",			/* PATH_RAY_GLOSSY */
			"singular",			/* PATH_RAY_SINGULAR */
			"transparent",		/* PATH_RAY_TRANSPARENT */
			"shadow",			/* PATH_RAY_SHADOW_OPAQUE */
			"shadow",			/* PATH_RAY_SHADOW_TRANSPARENT */

			"__unused__",
			"__unused__",
			"diffuse_ancestor",	/* PATH_RAY_DIFFUSE_ANCESTOR */
			"__unused__",
			"__unused__",
			"__unused__",		/* PATH_RAY_SINGLE_PASS_DONE */
			"volume_scatter",	/* PATH_RAY_VOLUME_SCATTER */
		};

		const int nraytypes = sizeof(raytypes)/sizeof(raytypes[0]);
		ss_shared->attribute("raytypes", TypeDesc(TypeDesc::STRING, nraytypes), raytypes);

		OSLShader::register_closures((OSLShadingSystem*)ss_shared);

		loaded_shaders.clear();
	}

	ss = ss_shared;
	services = services_shared;
	ss_shared_users++;
}

void OSLShaderManager::shading_system_free()
{
	/* shared shading system decrease users and destroy if no longer used */
	thread_scoped_lock lock(ss_shared_mutex);
	ss_shared_users--;

	if(ss_shared_users == 0) {
		delete ss_shared;
		ss_shared = NULL;

		delete services_shared;
		services_shared = NULL;
	}

	ss = NULL;
	services = NULL;
}

bool OSLShaderManager::osl_compile(const string& inputfile, const string& outputfile)
{
	vector<string> options;
	string stdosl_path;
	string shader_path = path_get("shader");

	/* specify output file name */
	options.push_back("-o");
	options.push_back(outputfile);

	/* specify standard include path */
	string include_path_arg = string("-I") + shader_path;
	options.push_back(include_path_arg);

	stdosl_path = path_get("shader/stdosl.h");

	/* compile */
	OSL::OSLCompiler *compiler = new OSL::OSLCompiler(&OSL::ErrorHandler::default_handler());
	bool ok = compiler->compile(string_view(inputfile), options, string_view(stdosl_path));
	delete compiler;

	return ok;
}

bool OSLShaderManager::osl_query(OSL::OSLQuery& query, const string& filepath)
{
	string searchpath = path_user_get("shaders");
	return query.open(filepath, searchpath);
}

static string shader_filepath_hash(const string& filepath, uint64_t modified_time)
{
	/* compute a hash from filepath and modified time to detect changes */
	MD5Hash md5;
	md5.append((const uint8_t*)filepath.c_str(), filepath.size());
	md5.append((const uint8_t*)&modified_time, sizeof(modified_time));

	return md5.get_hex();
}

const char *OSLShaderManager::shader_test_loaded(const string& hash)
{
	map<string, OSLShaderInfo>::iterator it = loaded_shaders.find(hash);
	return (it == loaded_shaders.end())? NULL: it->first.c_str();
}

OSLShaderInfo *OSLShaderManager::shader_loaded_info(const string& hash)
{
	map<string, OSLShaderInfo>::iterator it = loaded_shaders.find(hash);
	return (it == loaded_shaders.end())? NULL: &it->second;
}

const char *OSLShaderManager::shader_load_filepath(string filepath)
{
	size_t len = filepath.size();
	string extension = filepath.substr(len - 4);
	uint64_t modified_time = path_modified_time(filepath);

	if(extension == ".osl") {
		/* .OSL File */
		string osopath = filepath.substr(0, len - 4) + ".oso";
		uint64_t oso_modified_time = path_modified_time(osopath);

		/* test if we have loaded the corresponding .OSO already */
		if(oso_modified_time != 0) {
			const char *hash = shader_test_loaded(shader_filepath_hash(osopath, oso_modified_time));

			if(hash)
				return hash;
		}

		/* autocompile .OSL to .OSO if needed */
		if(oso_modified_time == 0 || (oso_modified_time < modified_time)) {
			OSLShaderManager::osl_compile(filepath, osopath);
			modified_time = path_modified_time(osopath);
		}
		else
			modified_time = oso_modified_time;

		filepath = osopath;
	}
	else {
		if(extension == ".oso") {
			/* .OSO File, nothing to do */
		}
		else if(path_dirname(filepath) == "") {
			/* .OSO File in search path */
			filepath = path_join(path_user_get("shaders"), filepath + ".oso");
		}
		else {
			/* unknown file */
			return NULL;
		}

		/* test if we have loaded this .OSO already */
		const char *hash = shader_test_loaded(shader_filepath_hash(filepath, modified_time));

		if(hash)
			return hash;
	}

	/* read oso bytecode from file */
	string bytecode_hash = shader_filepath_hash(filepath, modified_time);
	string bytecode;

	if(!path_read_text(filepath, bytecode)) {
		fprintf(stderr, "Cycles shader graph: failed to read file %s\n", filepath.c_str());
		OSLShaderInfo info;
		loaded_shaders[bytecode_hash] = info; /* to avoid repeat tries */
		return NULL;
	}

	return shader_load_bytecode(bytecode_hash, bytecode);
}

const char *OSLShaderManager::shader_load_bytecode(const string& hash, const string& bytecode)
{
	ss->LoadMemoryCompiledShader(hash.c_str(), bytecode.c_str());

	OSLShaderInfo info;

	if(!info.query.open_bytecode(bytecode)) {
		fprintf(stderr, "OSL query error: %s\n", info.query.geterror().c_str());
	}

	/* this is a bit weak, but works */
	info.has_surface_emission = (bytecode.find("\"emission\"") != string::npos);
	info.has_surface_transparent = (bytecode.find("\"transparent\"") != string::npos);
	info.has_surface_bssrdf = (bytecode.find("\"bssrdf\"") != string::npos);

	loaded_shaders[hash] = info;

	return loaded_shaders.find(hash)->first.c_str();
}

OSLNode *OSLShaderManager::osl_node(const std::string& filepath,
                                    const std::string& bytecode_hash,
                                    const std::string& bytecode)
{
	/* create query */
	const char *hash;

	if(!filepath.empty()) {
		hash = shader_load_filepath(filepath);
	}
	else {
		hash = shader_test_loaded(bytecode_hash);
		if(!hash)
			hash = shader_load_bytecode(bytecode_hash, bytecode);
	}

	if(!hash) {
		return NULL;
	}

	OSLShaderInfo *info = shader_loaded_info(hash);

	/* count number of inputs */
	size_t num_inputs = 0;

	for(int i = 0; i < info->query.nparams(); i++) {
		const OSL::OSLQuery::Parameter *param = info->query.getparam(i);

		/* skip unsupported types */
		if(param->varlenarray || param->isstruct || param->type.arraylen > 1)
			continue;

		if(!param->isoutput)
			num_inputs++;
	}

	/* create node */
	OSLNode *node = OSLNode::create(num_inputs);

	/* add new sockets from parameters */
	set<void*> used_sockets;

	for(int i = 0; i < info->query.nparams(); i++) {
		const OSL::OSLQuery::Parameter *param = info->query.getparam(i);

		/* skip unsupported types */
		if(param->varlenarray || param->isstruct || param->type.arraylen > 1)
			continue;

		SocketType::Type socket_type;

		if(param->isclosure) {
			socket_type = SocketType::CLOSURE;
		}
		else if(param->type.vecsemantics != TypeDesc::NOSEMANTICS) {
			if(param->type.vecsemantics == TypeDesc::COLOR)
				socket_type = SocketType::COLOR;
			else if(param->type.vecsemantics == TypeDesc::POINT)
				socket_type = SocketType::POINT;
			else if(param->type.vecsemantics == TypeDesc::VECTOR)
				socket_type = SocketType::VECTOR;
			else if(param->type.vecsemantics == TypeDesc::NORMAL)
				socket_type = SocketType::NORMAL;
			else
				continue;

			if(!param->isoutput && param->validdefault) {
				float3 *default_value = (float3*)node->input_default_value();
				default_value->x = param->fdefault[0];
				default_value->y = param->fdefault[1];
				default_value->z = param->fdefault[2];
			}
		}
		else if(param->type.aggregate == TypeDesc::SCALAR) {
			if(param->type.basetype == TypeDesc::INT) {
				socket_type = SocketType::INT;

				if(!param->isoutput && param->validdefault) {
					*(int*)node->input_default_value() = param->idefault[0];
				}
			}
			else if(param->type.basetype == TypeDesc::FLOAT) {
				socket_type = SocketType::FLOAT;

				if(!param->isoutput && param->validdefault) {
					*(float*)node->input_default_value() = param->fdefault[0];
				}
			}
			else if(param->type.basetype == TypeDesc::STRING) {
				socket_type = SocketType::STRING;

				if(!param->isoutput && param->validdefault) {
					*(ustring*)node->input_default_value() = param->sdefault[0];
				}
			}
			else
				continue;
		}
		else
			continue;

		if(param->isoutput) {
			node->add_output(param->name, socket_type);
		}
		else {
			node->add_input(param->name, socket_type);
		}
	}

	/* set bytcode hash or filepath */
	if(!bytecode_hash.empty()) {
		node->bytecode_hash = bytecode_hash;
	}
	else {
		node->filepath = filepath;
	}

	/* Generate inputs and outputs */
	node->create_inputs_outputs(node->type);

	return node;
}

/* Graph Compiler */

OSLCompiler::OSLCompiler(void *manager_, void *shadingsys_, ImageManager *image_manager_)
{
	manager = manager_;
	shadingsys = shadingsys_;
	image_manager = image_manager_;
	current_type = SHADER_TYPE_SURFACE;
	current_shader = NULL;
	background = false;
}

string OSLCompiler::id(ShaderNode *node)
{
	/* assign layer unique name based on pointer address + bump mode */
	stringstream stream;
	stream << "node_" << node->type->name << "_" << node;

	return stream.str();
}

string OSLCompiler::compatible_name(ShaderNode *node, ShaderInput *input)
{
	string sname(input->name().string());
	size_t i;

	/* strip whitespace */
	while((i = sname.find(" ")) != string::npos)
		sname.replace(i, 1, "");
	
	/* if output exists with the same name, add "In" suffix */
	foreach(ShaderOutput *output, node->outputs) {
		if(input->name() == output->name()) {
			sname += "In";
			break;
		}
	}
	
	return sname;
}

string OSLCompiler::compatible_name(ShaderNode *node, ShaderOutput *output)
{
	string sname(output->name().string());
	size_t i;

	/* strip whitespace */
	while((i = sname.find(" ")) != string::npos)
		sname.replace(i, 1, "");
	
	/* if input exists with the same name, add "Out" suffix */
	foreach(ShaderInput *input, node->inputs) {
		if(input->name() == output->name()) {
			sname += "Out";
			break;
		}
	}
	
	return sname;
}

bool OSLCompiler::node_skip_input(ShaderNode *node, ShaderInput *input)
{
	/* exception for output node, only one input is actually used
	 * depending on the current shader type */
	
	if(input->flags() & SocketType::SVM_INTERNAL)
		return true;

	if(node->special_type == SHADER_SPECIAL_TYPE_OUTPUT) {
		if(input->name() == "Surface" && current_type != SHADER_TYPE_SURFACE)
			return true;
		if(input->name() == "Volume" && current_type != SHADER_TYPE_VOLUME)
			return true;
		if(input->name() == "Displacement" && current_type != SHADER_TYPE_DISPLACEMENT)
			return true;
		if(input->name() == "Normal" && current_type != SHADER_TYPE_BUMP)
			return true;
	}
	else if(node->special_type == SHADER_SPECIAL_TYPE_BUMP) {
		if(input->name() == "Height")
			return true;
	}
	else if(current_type == SHADER_TYPE_DISPLACEMENT && input->link && input->link->parent->special_type == SHADER_SPECIAL_TYPE_BUMP)
		return true;

	return false;
}

void OSLCompiler::add(ShaderNode *node, const char *name, bool isfilepath)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;

	/* load filepath */
	if(isfilepath) {
		name = ((OSLShaderManager*)manager)->shader_load_filepath(name);

		if(name == NULL)
			return;
	}

	/* pass in fixed parameter values */
	foreach(ShaderInput *input, node->inputs) {
		if(!input->link) {
			/* checks to untangle graphs */
			if(node_skip_input(node, input))
				continue;
			/* already has default value assigned */
			else if(input->flags() & SocketType::DEFAULT_LINK_MASK)
				continue;

			string param_name = compatible_name(node, input);
			const SocketType& socket = input->socket_type;
			switch(input->type()) {
				case SocketType::COLOR:
					parameter_color(param_name.c_str(), node->get_float3(socket));
					break;
				case SocketType::POINT:
					parameter_point(param_name.c_str(), node->get_float3(socket));
					break;
				case SocketType::VECTOR:
					parameter_vector(param_name.c_str(), node->get_float3(socket));
					break;
				case SocketType::NORMAL:
					parameter_normal(param_name.c_str(), node->get_float3(socket));
					break;
				case SocketType::FLOAT:
					parameter(param_name.c_str(), node->get_float(socket));
					break;
				case SocketType::INT:
					parameter(param_name.c_str(), node->get_int(socket));
					break;
				case SocketType::STRING:
					parameter(param_name.c_str(), node->get_string(socket));
					break;
				case SocketType::CLOSURE:
				case SocketType::UNDEFINED:
				default:
					break;
			}
		}
	}

	/* create shader of the appropriate type. OSL only distinguishes between "surface"
	 * and "displacement" atm */
	if(current_type == SHADER_TYPE_SURFACE)
		ss->Shader("surface", name, id(node).c_str());
	else if(current_type == SHADER_TYPE_VOLUME)
		ss->Shader("surface", name, id(node).c_str());
	else if(current_type == SHADER_TYPE_DISPLACEMENT)
		ss->Shader("displacement", name, id(node).c_str());
	else if(current_type == SHADER_TYPE_BUMP)
		ss->Shader("displacement", name, id(node).c_str());
	else
		assert(0);
	
	/* link inputs to other nodes */
	foreach(ShaderInput *input, node->inputs) {
		if(input->link) {
			if(node_skip_input(node, input))
				continue;

			/* connect shaders */
			string id_from = id(input->link->parent);
			string id_to = id(node);
			string param_from = compatible_name(input->link->parent, input->link);
			string param_to = compatible_name(node, input);

			ss->ConnectShaders(id_from.c_str(), param_from.c_str(), id_to.c_str(), param_to.c_str());
		}
	}

	/* test if we shader contains specific closures */
	OSLShaderInfo *info = ((OSLShaderManager*)manager)->shader_loaded_info(name);

	if(current_type == SHADER_TYPE_SURFACE) {
		if(info) {
			if(info->has_surface_emission)
				current_shader->has_surface_emission = true;
			if(info->has_surface_transparent)
				current_shader->has_surface_transparent = true;
			if(info->has_surface_bssrdf) {
				current_shader->has_surface_bssrdf = true;
				current_shader->has_bssrdf_bump = true; /* can't detect yet */
			}
		}

		if(node->has_spatial_varying()) {
			current_shader->has_surface_spatial_varying = true;
		}
	}
	else if(current_type == SHADER_TYPE_VOLUME) {
		if(node->has_spatial_varying())
			current_shader->has_volume_spatial_varying = true;
	}

	if(node->has_object_dependency()) {
		current_shader->has_object_dependency = true;
	}

	if(node->has_integrator_dependency()) {
		current_shader->has_integrator_dependency = true;
	}
}

static TypeDesc array_typedesc(TypeDesc typedesc, int arraylength)
{
	return TypeDesc((TypeDesc::BASETYPE)typedesc.basetype,
	                (TypeDesc::AGGREGATE)typedesc.aggregate,
	                (TypeDesc::VECSEMANTICS)typedesc.vecsemantics,
	                arraylength);
}

void OSLCompiler::parameter(ShaderNode* node, const char *name)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ustring uname = ustring(name);
	const SocketType& socket = *(node->type->find_input(uname));

	switch(socket.type)
	{
		case SocketType::BOOLEAN:
		{
			int value = node->get_bool(socket);
			ss->Parameter(name, TypeDesc::TypeInt, &value);
			break;
		}
		case SocketType::FLOAT:
		{
			float value = node->get_float(socket);
			ss->Parameter(uname, TypeDesc::TypeFloat, &value);
			break;
		}
		case SocketType::INT:
		{
			int value = node->get_int(socket);
			ss->Parameter(uname, TypeDesc::TypeInt, &value);
			break;
		}
		case SocketType::COLOR:
		{
			float3 value = node->get_float3(socket);
			ss->Parameter(uname, TypeDesc::TypeColor, &value);
			break;
		}
		case SocketType::VECTOR:
		{
			float3 value = node->get_float3(socket);
			ss->Parameter(uname, TypeDesc::TypeVector, &value);
			break;
		}
		case SocketType::POINT:
		{
			float3 value = node->get_float3(socket);
			ss->Parameter(uname, TypeDesc::TypePoint, &value);
			break;
		}
		case SocketType::NORMAL:
		{
			float3 value = node->get_float3(socket);
			ss->Parameter(uname, TypeDesc::TypeNormal, &value);
			break;
		}
		case SocketType::POINT2:
		{
			float2 value = node->get_float2(socket);
			ss->Parameter(uname, TypeDesc(TypeDesc::FLOAT, TypeDesc::VEC2, TypeDesc::POINT), &value);
			break;
		}
		case SocketType::STRING:
		{
			ustring value = node->get_string(socket);
			ss->Parameter(uname, TypeDesc::TypeString, &value);
			break;
		}
		case SocketType::ENUM:
		{
			ustring value = node->get_string(socket);
			ss->Parameter(uname, TypeDesc::TypeString, &value);
			break;
		}
		case SocketType::TRANSFORM:
		{
			Transform value = node->get_transform(socket);
			ss->Parameter(uname, TypeDesc::TypeMatrix, &value);
			break;
		}
		case SocketType::BOOLEAN_ARRAY:
		{
			// OSL does not support booleans, so convert to int
			const array<bool>& value = node->get_bool_array(socket);
			array<int> intvalue(value.size());
			for(size_t i = 0; i < value.size(); i++)
				intvalue[i] = value[i];
			ss->Parameter(uname, array_typedesc(TypeDesc::TypeInt, value.size()), intvalue.data());
			break;
		}
		case SocketType::FLOAT_ARRAY:
		{
			const array<float>& value = node->get_float_array(socket);
			ss->Parameter(uname, array_typedesc(TypeDesc::TypeFloat, value.size()), value.data());
			break;
		}
		case SocketType::INT_ARRAY:
		{
			const array<int>& value = node->get_int_array(socket);
			ss->Parameter(uname, array_typedesc(TypeDesc::TypeInt, value.size()), value.data());
			break;
		}
		case SocketType::COLOR_ARRAY:
		case SocketType::VECTOR_ARRAY:
		case SocketType::POINT_ARRAY:
		case SocketType::NORMAL_ARRAY:
		{
			TypeDesc typedesc;

			switch(socket.type)
			{
				case SocketType::COLOR_ARRAY: typedesc = TypeDesc::TypeColor; break;
				case SocketType::VECTOR_ARRAY: typedesc = TypeDesc::TypeVector; break;
				case SocketType::POINT_ARRAY: typedesc = TypeDesc::TypePoint; break;
				case SocketType::NORMAL_ARRAY: typedesc = TypeDesc::TypeNormal; break;
				default: assert(0); break;
			}

			// convert to tightly packed array since float3 has padding
			const array<float3>& value = node->get_float3_array(socket);
			array<float> fvalue(value.size() * 3);
			for(size_t i = 0, j = 0; i < value.size(); i++) {
				fvalue[j++] = value[i].x;
				fvalue[j++] = value[i].y;
				fvalue[j++] = value[i].z;
			}

			ss->Parameter(uname, array_typedesc(typedesc, value.size()), fvalue.data());
			break;
		}
		case SocketType::POINT2_ARRAY:
		{
			const array<float2>& value = node->get_float2_array(socket);
			ss->Parameter(uname, array_typedesc(TypeDesc(TypeDesc::FLOAT, TypeDesc::VEC2, TypeDesc::POINT), value.size()), value.data());
			break;
		}
		case SocketType::STRING_ARRAY:
		{
			const array<ustring>& value = node->get_string_array(socket);
			ss->Parameter(uname, array_typedesc(TypeDesc::TypeString, value.size()), value.data());
			break;
		}
		case SocketType::TRANSFORM_ARRAY:
		{
			const array<Transform>& value = node->get_transform_array(socket);
			ss->Parameter(uname, array_typedesc(TypeDesc::TypeMatrix, value.size()), value.data());
			break;
		}
		case SocketType::CLOSURE:
		case SocketType::NODE:
		case SocketType::NODE_ARRAY:
		case SocketType::UNDEFINED:
		case SocketType::UINT:
		{
			assert(0);
			break;
		}
	}
}

void OSLCompiler::parameter(const char *name, float f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeFloat, &f);
}

void OSLCompiler::parameter_color(const char *name, float3 f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeColor, &f);
}

void OSLCompiler::parameter_point(const char *name, float3 f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypePoint, &f);
}

void OSLCompiler::parameter_normal(const char *name, float3 f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeNormal, &f);
}

void OSLCompiler::parameter_vector(const char *name, float3 f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeVector, &f);
}

void OSLCompiler::parameter(const char *name, int f)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeInt, &f);
}

void OSLCompiler::parameter(const char *name, const char *s)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeString, &s);
}

void OSLCompiler::parameter(const char *name, ustring s)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	const char *str = s.c_str();
	ss->Parameter(name, TypeDesc::TypeString, &str);
}

void OSLCompiler::parameter(const char *name, const Transform& tfm)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	ss->Parameter(name, TypeDesc::TypeMatrix, (float*)&tfm);
}

void OSLCompiler::parameter_array(const char *name, const float f[], int arraylen)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	TypeDesc type = TypeDesc::TypeFloat;
	type.arraylen = arraylen;
	ss->Parameter(name, type, f);
}

void OSLCompiler::parameter_color_array(const char *name, const array<float3>& f)
{
	/* NB: cycles float3 type is actually 4 floats! need to use an explicit array */
	array<float[3]> table(f.size());

	for(int i = 0; i < f.size(); ++i) {
		table[i][0] = f[i].x;
		table[i][1] = f[i].y;
		table[i][2] = f[i].z;
	}

	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;
	TypeDesc type = TypeDesc::TypeColor;
	type.arraylen = table.size();
	ss->Parameter(name, type, table.data());
}

void OSLCompiler::find_dependencies(ShaderNodeSet& dependencies, ShaderInput *input)
{
	ShaderNode *node = (input->link)? input->link->parent: NULL;

	if(node != NULL && dependencies.find(node) == dependencies.end()) {
		foreach(ShaderInput *in, node->inputs)
			if(!node_skip_input(node, in))
				find_dependencies(dependencies, in);

		dependencies.insert(node);
	}
}

void OSLCompiler::generate_nodes(const ShaderNodeSet& nodes)
{
	ShaderNodeSet done;
	bool nodes_done;

	do {
		nodes_done = true;

		foreach(ShaderNode *node, nodes) {
			if(done.find(node) == done.end()) {
				bool inputs_done = true;

				foreach(ShaderInput *input, node->inputs)
					if(!node_skip_input(node, input))
						if(input->link && done.find(input->link->parent) == done.end())
							inputs_done = false;

				if(inputs_done) {
					node->compile(*this);
					done.insert(node);

					if(current_type == SHADER_TYPE_SURFACE) {
						if(node->has_surface_emission())
							current_shader->has_surface_emission = true;
						if(node->has_surface_transparent())
							current_shader->has_surface_transparent = true;
						if(node->has_spatial_varying())
							current_shader->has_surface_spatial_varying = true;
						if(node->has_surface_bssrdf()) {
							current_shader->has_surface_bssrdf = true;
							if(node->has_bssrdf_bump())
								current_shader->has_bssrdf_bump = true;
						}
					}
					else if(current_type == SHADER_TYPE_VOLUME) {
						if(node->has_spatial_varying())
							current_shader->has_volume_spatial_varying = true;
					}
				}
				else
					nodes_done = false;
			}
		}
	} while(!nodes_done);
}

OSL::ShaderGroupRef OSLCompiler::compile_type(Shader *shader, ShaderGraph *graph, ShaderType type)
{
	OSL::ShadingSystem *ss = (OSL::ShadingSystem*)shadingsys;

	current_type = type;

	OSL::ShaderGroupRef group = ss->ShaderGroupBegin(shader->name.c_str());

	ShaderNode *output = graph->output();
	ShaderNodeSet dependencies;

	if(type == SHADER_TYPE_SURFACE) {
		/* generate surface shader */
		find_dependencies(dependencies, output->input("Surface"));
		generate_nodes(dependencies);
		output->compile(*this);
	}
	else if(type == SHADER_TYPE_BUMP) {
		/* generate bump shader */
		find_dependencies(dependencies, output->input("Normal"));
		generate_nodes(dependencies);
		output->compile(*this);
	}
	else if(type == SHADER_TYPE_VOLUME) {
		/* generate volume shader */
		find_dependencies(dependencies, output->input("Volume"));
		generate_nodes(dependencies);
		output->compile(*this);
	}
	else if(type == SHADER_TYPE_DISPLACEMENT) {
		/* generate displacement shader */
		find_dependencies(dependencies, output->input("Displacement"));
		generate_nodes(dependencies);
		output->compile(*this);
	}
	else
		assert(0);

	ss->ShaderGroupEnd();

	return group;
}

void OSLCompiler::compile(Scene *scene, OSLGlobals *og, Shader *shader)
{
	if(shader->need_update) {
		ShaderGraph *graph = shader->graph;
		ShaderNode *output = (graph)? graph->output(): NULL;

		/* copy graph for shader with bump mapping */
		if(output->input("Surface")->link && output->input("Displacement")->link)
			if(!shader->graph_bump)
				shader->graph_bump = shader->graph->copy();

		/* finalize */
		shader->graph->finalize(scene,
		                        false,
		                        shader->has_integrator_dependency);
		if(shader->graph_bump) {
			shader->graph_bump->finalize(scene,
			                             true,
			                             shader->has_integrator_dependency,
			                             shader->displacement_method == DISPLACE_BOTH);
		}

		current_shader = shader;

		shader->has_surface = false;
		shader->has_surface_emission = false;
		shader->has_surface_transparent = false;
		shader->has_surface_bssrdf = false;
		shader->has_bssrdf_bump = false;
		shader->has_volume = false;
		shader->has_displacement = false;
		shader->has_surface_spatial_varying = false;
		shader->has_volume_spatial_varying = false;
		shader->has_object_dependency = false;
		shader->has_integrator_dependency = false;

		/* generate surface shader */
		if(shader->used && graph && output->input("Surface")->link) {
			shader->osl_surface_ref = compile_type(shader, shader->graph, SHADER_TYPE_SURFACE);

			if(shader->graph_bump && shader->displacement_method != DISPLACE_TRUE)
				shader->osl_surface_bump_ref = compile_type(shader, shader->graph_bump, SHADER_TYPE_BUMP);
			else
				shader->osl_surface_bump_ref = OSL::ShaderGroupRef();

			shader->has_surface = true;
		}
		else {
			shader->osl_surface_ref = OSL::ShaderGroupRef();
			shader->osl_surface_bump_ref = OSL::ShaderGroupRef();
		}

		/* generate volume shader */
		if(shader->used && graph && output->input("Volume")->link) {
			shader->osl_volume_ref = compile_type(shader, shader->graph, SHADER_TYPE_VOLUME);
			shader->has_volume = true;
		}
		else
			shader->osl_volume_ref = OSL::ShaderGroupRef();

		/* generate displacement shader */
		if(shader->used && graph && output->input("Displacement")->link) {
			shader->osl_displacement_ref = compile_type(shader, shader->graph, SHADER_TYPE_DISPLACEMENT);
			shader->has_displacement = true;
		}
		else
			shader->osl_displacement_ref = OSL::ShaderGroupRef();
	}

	/* push state to array for lookup */
	og->surface_state.push_back(shader->osl_surface_ref);
	og->volume_state.push_back(shader->osl_volume_ref);
	og->displacement_state.push_back(shader->osl_displacement_ref);
	og->bump_state.push_back(shader->osl_surface_bump_ref);
}

#else

void OSLCompiler::add(ShaderNode * /*node*/, const char * /*name*/, bool /*isfilepath*/)
{
}

void OSLCompiler::parameter(ShaderNode * /*node*/, const char * /*name*/)
{
}

void OSLCompiler::parameter(const char * /*name*/, float /*f*/)
{
}

void OSLCompiler::parameter_color(const char * /*name*/, float3 /*f*/)
{
}

void OSLCompiler::parameter_vector(const char * /*name*/, float3 /*f*/)
{
}

void OSLCompiler::parameter_point(const char * /*name*/, float3 /*f*/)
{
}

void OSLCompiler::parameter_normal(const char * /*name*/, float3 /*f*/)
{
}

void OSLCompiler::parameter(const char * /*name*/, int /*f*/)
{
}

void OSLCompiler::parameter(const char * /*name*/, const char * /*s*/)
{
}

void OSLCompiler::parameter(const char * /*name*/, ustring /*s*/)
{
}

void OSLCompiler::parameter(const char * /*name*/, const Transform& /*tfm*/)
{
}

void OSLCompiler::parameter_array(const char * /*name*/, const float /*f*/[], int /*arraylen*/)
{
}

void OSLCompiler::parameter_color_array(const char * /*name*/, const array<float3>& /*f*/)
{
}

#endif /* WITH_OSL */

CCL_NAMESPACE_END