/*
 Copyright (c) 2013 yvt
 
 This file is part of OpenSpades.
 
 OpenSpades is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.
 
 OpenSpades is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with OpenSpades.  If not, see <http://www.gnu.org/licenses/>.
 
 */

#include "GLProgram.h"
#include "GLShader.h"
#include "../Core/Exception.h"
#include "../Core/Debug.h"
#include <string.h>
#include <stdio.h>

namespace  spades {
	namespace draw {
		GLProgram::GLProgram(IGLDevice *d, std::string name):
		device(d),name(name){
			SPADES_MARK_FUNCTION();
			handle = device->CreateProgram();
		}
		GLProgram::~GLProgram() {
			SPADES_MARK_FUNCTION();
			device->DeleteProgram(handle);
		}
		
		void GLProgram::Attach(spades::draw::GLShader *shader){
			SPADES_MARK_FUNCTION();
			device->AttachShader(handle, shader->GetHandle());
		}
		
		void GLProgram::Attach(IGLDevice::UInteger shader){
			SPADES_MARK_FUNCTION();
			device->AttachShader(handle, shader);
		}
		
		void GLProgram::Link(){
			SPADES_MARK_FUNCTION();
			device->LinkProgram(handle);
			
			std::vector<char> errMsg;
			errMsg.resize(device->GetProgramInteger(handle, IGLDevice::InfoLogLength) + 1);
			
			IGLDevice::Sizei outLen;
			device->GetProgramInfoLog(handle, errMsg.size(), &outLen, errMsg.data());
			errMsg[outLen] = 0;
			
			std::string err = errMsg.data();
			
			if(device->GetProgramInteger(handle, IGLDevice::LinkStatus) == 0){
				// error
				
				SPRaise("Error while linking a program '%s':\n\n%s",name.c_str(), err.c_str());
			}else{
				if(errMsg.size() > 4){
					SPLog("Messages for linking program '%s':\n%s",
						   name.c_str(), err.c_str());
				}
			}
			
			linked = true;
		}
		
		void GLProgram::Validate(){
			SPADES_MARK_FUNCTION();
			device->ValidateProgram(handle);
			
			if(device->GetProgramInteger(handle, IGLDevice::ValidateStatus) == 0){
				// error
				std::vector<char> errMsg;
				errMsg.resize(device->GetProgramInteger(handle, IGLDevice::InfoLogLength) + 1);
				
				IGLDevice::Sizei outLen;
				device->GetShaderInfoLog(handle, errMsg.size(), &outLen, errMsg.data());
				errMsg[outLen] = 0;
				
				
				std::string err = errMsg.data();
				SPRaise("Validation error while linking a program '%s':\n\n%s",
						name.c_str(),errMsg.data());
			}
			
		}
		
		
		void GLProgram::Use(){
			SPADES_MARK_FUNCTION();
			device->UseProgram(handle);
		}
	}
}