#include "stdafx.h"
#include "program.h"
#include "state_tracker.hpp"

#include "Emu/system_config.h"

namespace gl
{
	namespace glsl
	{
		void shader::precompile()
		{
			const char* str = source.c_str();
			const GLint length = ::narrow<GLint>(source.length());

			if (g_cfg.video.log_programs)
			{
				std::string base_name;
				switch (type)
				{
				case ::glsl::program_domain::glsl_vertex_program:
					base_name = "shaderlog/VertexProgram";
					break;
				case ::glsl::program_domain::glsl_fragment_program:
					base_name = "shaderlog/FragmentProgram";
					break;
				case ::glsl::program_domain::glsl_compute_program:
					base_name = "shaderlog/ComputeProgram";
					break;
				}

				fs::file(fs::get_cache_dir() + base_name + std::to_string(m_id) + ".glsl", fs::rewrite).write(str, length);
			}

			glShaderSource(m_id, 1, &str, &length);

			m_init_fence.create();
			flush_command_queue(m_init_fence);
		}

		void shader::create(::glsl::program_domain type_, const std::string & src)
		{
			type = type_;
			source = src;

			GLenum shader_type{};
			switch (type)
			{
			case ::glsl::program_domain::glsl_vertex_program:
				shader_type = GL_VERTEX_SHADER;
				break;
			case ::glsl::program_domain::glsl_fragment_program:
				shader_type = GL_FRAGMENT_SHADER;
				break;
			case ::glsl::program_domain::glsl_compute_program:
				shader_type = GL_COMPUTE_SHADER;
				break;
			default:
				rsx_log.fatal("gl::glsl::shader::compile(): Unhandled shader type (%d)", +type_);
				return;
			}

			m_id = glCreateShader(shader_type);
			precompile();
		}

		shader& shader::compile()
		{
			std::lock_guard lock(m_compile_lock);
			if (m_is_compiled)
			{
				// Another thread compiled this already
				return *this;
			}

			ensure(!m_init_fence.is_empty()); // Do not attempt to compile a shader_view!!
			m_init_fence.server_wait_sync();

			glCompileShader(m_id);

			GLint status = GL_FALSE;
			glGetShaderiv(m_id, GL_COMPILE_STATUS, &status);

			if (status == GL_FALSE)
			{
				GLint length = 0;
				glGetShaderiv(m_id, GL_INFO_LOG_LENGTH, &length);

				std::string error_msg;
				if (length)
				{
					std::unique_ptr<GLchar[]> buf(new char[length + 1]);
					glGetShaderInfoLog(m_id, length, nullptr, buf.get());
					error_msg = buf.get();
				}

				rsx_log.fatal("Compilation failed: %s\nsource: %s", error_msg, source);
			}

			m_compiled_fence.create();
			flush_command_queue(m_compiled_fence);

			m_is_compiled = true;
			return *this;
		}

		bool program::uniforms_t::has_location(const std::string & name, int* location)
		{
			auto found = locations.find(name);
			if (found != locations.end())
			{
				if (location)
				{
					*location = found->second;
				}

				return (found->second >= 0);
			}

			auto result = glGetUniformLocation(m_program.id(), name.c_str());
			locations[name] = result;

			if (location)
			{
				*location = result;
			}

			return (result >= 0);
		}

		GLint program::uniforms_t::location(const std::string& name)
		{
			auto found = locations.find(name);
			if (found != locations.end())
			{
				if (found->second >= 0)
				{
					return found->second;
				}
				else
				{
					rsx_log.fatal("%s not found.", name);
					return -1;
				}
			}

			auto result = glGetUniformLocation(m_program.id(), name.c_str());

			if (result < 0)
			{
				rsx_log.fatal("%s not found.", name);
				return result;
			}

			locations[name] = result;
			return result;
		}

		void program::link(std::function<void(program*)> init_func)
		{
			glLinkProgram(m_id);

			GLint status = GL_FALSE;
			glGetProgramiv(m_id, GL_LINK_STATUS, &status);

			if (status == GL_FALSE)
			{
				GLint length = 0;
				glGetProgramiv(m_id, GL_INFO_LOG_LENGTH, &length);

				std::string error_msg;
				if (length)
				{
					std::unique_ptr<GLchar[]> buf(new char[length + 1]);
					glGetProgramInfoLog(m_id, length, nullptr, buf.get());
					error_msg = buf.get();
				}

				rsx_log.fatal("Linkage failed: %s", error_msg);
			}
			else
			{
				if (init_func)
				{
					init_func(this);
				}

				m_fence.create();
				flush_command_queue(m_fence);
			}
		}

		void program::validate()
		{
			glValidateProgram(m_id);

			GLint status = GL_FALSE;
			glGetProgramiv(m_id, GL_VALIDATE_STATUS, &status);

			if (status == GL_FALSE)
			{
				GLint length = 0;
				glGetProgramiv(m_id, GL_INFO_LOG_LENGTH, &length);

				std::string error_msg;
				if (length)
				{
					std::unique_ptr<GLchar[]> buf(new char[length + 1]);
					glGetProgramInfoLog(m_id, length, nullptr, buf.get());
					error_msg = buf.get();
				}

				rsx_log.error("Validation failed: %s", error_msg.c_str());
			}
		}
	}
}