#include "rasterizer_gles3.h"
#include "os/os.h"
#include "globals.h"
#include "gl_context/context_gl.h"
#include <string.h>
RasterizerStorage *RasterizerGLES3::get_storage() {

	return storage;
}

RasterizerCanvas *RasterizerGLES3::get_canvas() {

	return canvas;
}

RasterizerScene *RasterizerGLES3::get_scene() {

	return scene;
}

#define _EXT_DEBUG_OUTPUT_SYNCHRONOUS_ARB 0x8242
#define _EXT_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH_ARB 0x8243
#define _EXT_DEBUG_CALLBACK_FUNCTION_ARB 0x8244
#define _EXT_DEBUG_CALLBACK_USER_PARAM_ARB 0x8245
#define _EXT_DEBUG_SOURCE_API_ARB 0x8246
#define _EXT_DEBUG_SOURCE_WINDOW_SYSTEM_ARB 0x8247
#define _EXT_DEBUG_SOURCE_SHADER_COMPILER_ARB 0x8248
#define _EXT_DEBUG_SOURCE_THIRD_PARTY_ARB 0x8249
#define _EXT_DEBUG_SOURCE_APPLICATION_ARB 0x824A
#define _EXT_DEBUG_SOURCE_OTHER_ARB 0x824B
#define _EXT_DEBUG_TYPE_ERROR_ARB 0x824C
#define _EXT_DEBUG_TYPE_DEPRECATED_BEHAVIOR_ARB 0x824D
#define _EXT_DEBUG_TYPE_UNDEFINED_BEHAVIOR_ARB 0x824E
#define _EXT_DEBUG_TYPE_PORTABILITY_ARB 0x824F
#define _EXT_DEBUG_TYPE_PERFORMANCE_ARB 0x8250
#define _EXT_DEBUG_TYPE_OTHER_ARB 0x8251
#define _EXT_MAX_DEBUG_MESSAGE_LENGTH_ARB 0x9143
#define _EXT_MAX_DEBUG_LOGGED_MESSAGES_ARB 0x9144
#define _EXT_DEBUG_LOGGED_MESSAGES_ARB 0x9145
#define _EXT_DEBUG_SEVERITY_HIGH_ARB 0x9146
#define _EXT_DEBUG_SEVERITY_MEDIUM_ARB 0x9147
#define _EXT_DEBUG_SEVERITY_LOW_ARB 0x9148
#define _EXT_DEBUG_OUTPUT 0x92E0

#ifdef WINDOWS_ENABLED
#define GLAPIENTRY APIENTRY
#else
#define GLAPIENTRY
#endif

static void GLAPIENTRY _gl_debug_print(GLenum source,GLenum type,GLuint id,GLenum severity,GLsizei length,const GLchar *message,const GLvoid *userParam)
{

	if (type==_EXT_DEBUG_TYPE_OTHER_ARB)
		return;

	print_line("mesege");
	char debSource[256], debType[256], debSev[256];
    if(source == _EXT_DEBUG_SOURCE_API_ARB)
	strcpy(debSource, "OpenGL");
    else if(source == _EXT_DEBUG_SOURCE_WINDOW_SYSTEM_ARB)
	strcpy(debSource, "Windows");
    else if(source == _EXT_DEBUG_SOURCE_SHADER_COMPILER_ARB)
	strcpy(debSource, "Shader Compiler");
    else if(source == _EXT_DEBUG_SOURCE_THIRD_PARTY_ARB)
	strcpy(debSource, "Third Party");
    else if(source == _EXT_DEBUG_SOURCE_APPLICATION_ARB)
	strcpy(debSource, "Application");
    else if(source == _EXT_DEBUG_SOURCE_OTHER_ARB)
	strcpy(debSource, "Other");

    if(type == _EXT_DEBUG_TYPE_ERROR_ARB)
	strcpy(debType, "Error");
    else if(type == _EXT_DEBUG_TYPE_DEPRECATED_BEHAVIOR_ARB)
	strcpy(debType, "Deprecated behavior");
    else if(type == _EXT_DEBUG_TYPE_UNDEFINED_BEHAVIOR_ARB)
	strcpy(debType, "Undefined behavior");
    else if(type == _EXT_DEBUG_TYPE_PORTABILITY_ARB)
	strcpy(debType, "Portability");
    else if(type == _EXT_DEBUG_TYPE_PERFORMANCE_ARB)
	strcpy(debType, "Performance");
    else if(type == _EXT_DEBUG_TYPE_OTHER_ARB)
	strcpy(debType, "Other");

    if(severity == _EXT_DEBUG_SEVERITY_HIGH_ARB)
	strcpy(debSev, "High");
    else if(severity == _EXT_DEBUG_SEVERITY_MEDIUM_ARB)
	strcpy(debSev, "Medium");
    else if(severity == _EXT_DEBUG_SEVERITY_LOW_ARB)
	strcpy(debSev, "Low");

	String output = String()+ "GL ERROR: Source: " + debSource + "\tType: " + debType + "\tID: " + itos(id) + "\tSeverity: " + debSev + "\tMessage: " + message;

	ERR_PRINTS(output);

}


typedef void (*DEBUGPROCARB)(GLenum source,
					     GLenum type,
					     GLuint id,
					     GLenum severity,
					     GLsizei length,
					     const char* message,
					     const void* userParam);

typedef void (* DebugMessageCallbackARB) (DEBUGPROCARB callback, const void *userParam);

void RasterizerGLES3::initialize() {

	if (OS::get_singleton()->is_stdout_verbose()) {
		print_line("Using GLES3 video driver");
	}

#ifdef GLEW_ENABLED
	GLuint res = glewInit();
	ERR_FAIL_COND(res!=GLEW_OK);
	if (OS::get_singleton()->is_stdout_verbose()) {
		print_line(String("GLES2: Using GLEW ") + (const char*) glewGetString(GLEW_VERSION));
	}

	// Check for GL 2.1 compatibility, if not bail out
	if (!glewIsSupported("GL_VERSION_3_0")) {
		ERR_PRINT("Your system's graphic drivers seem not to support OpenGL 3.0+ / GLES 3.0, sorry :(\n"
			  "Try a drivers update, buy a new GPU or try software rendering on Linux; Godot will now crash with a segmentation fault.");
		OS::get_singleton()->alert("Your system's graphic drivers seem not to support OpenGL 3.0+ / GLES 3.0, sorry :(\n"
					   "Godot Engine will self-destruct as soon as you acknowledge this error message.",
					   "Fatal error: Insufficient OpenGL / GLES drivers");
		// TODO: If it's even possible, we should stop the execution without segfault and memory leaks :)
	}
#endif

#ifdef GLAD_ENABLED

	if(!gladLoadGL()) {
		ERR_PRINT("Error initializing GLAD");
	}

#ifdef __APPLE__
	// FIXME glDebugMessageCallbackARB does not seem to work on Mac OS X and opengl 3, this may be an issue with our opengl canvas..
#else
	glEnable(_EXT_DEBUG_OUTPUT_SYNCHRONOUS_ARB);
	glDebugMessageCallbackARB(_gl_debug_print, NULL);
	glEnable(_EXT_DEBUG_OUTPUT);
#endif

#endif


/*	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_ERROR_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_PORTABILITY_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_PERFORMANCE_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageControlARB(GL_DEBUG_SOURCE_API_ARB,GL_DEBUG_TYPE_OTHER_ARB,GL_DEBUG_SEVERITY_HIGH_ARB,0,NULL,GL_TRUE);
	glDebugMessageInsertARB(

			GL_DEBUG_SOURCE_API_ARB,
			GL_DEBUG_TYPE_OTHER_ARB, 1,
			GL_DEBUG_SEVERITY_HIGH_ARB,5, "hello");

*/
	storage->initialize();
	canvas->initialize();
	scene->initialize();
}

void RasterizerGLES3::begin_frame(){

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

	double time_total = double(tick)/1000000.0;

	storage->frame.time[0]=time_total;
	storage->frame.time[1]=Math::fmod(time_total,3600);
	storage->frame.time[2]=Math::fmod(time_total,900);
	storage->frame.time[3]=Math::fmod(time_total,60);
	storage->frame.count++;
	storage->frame.delta = double(tick-storage->frame.prev_tick)/1000000.0;
	if (storage->frame.prev_tick==0) {
		//to avoid hiccups
		storage->frame.delta=0.001;
	}

	storage->frame.prev_tick=tick;


	storage->update_dirty_resources();


	storage->info.render_object_count=0;
	storage->info.render_material_switch_count=0;
	storage->info.render_surface_switch_count=0;
	storage->info.render_shader_rebind_count=0;
	storage->info.render_vertices_count=0;


	scene->iteration();




}

void RasterizerGLES3::set_current_render_target(RID p_render_target){

	if (!p_render_target.is_valid() && storage->frame.current_rt && storage->frame.clear_request) {
		//handle pending clear request, if the framebuffer was not cleared
		glBindFramebuffer(GL_FRAMEBUFFER,storage->frame.current_rt->fbo);
		print_line("unbind clear of: "+storage->frame.clear_request_color);
		glClearColor(
			storage->frame.clear_request_color.r,
			storage->frame.clear_request_color.g,
			storage->frame.clear_request_color.b,
			storage->frame.clear_request_color.a );

		glClear(GL_COLOR_BUFFER_BIT);

	}

	if (p_render_target.is_valid()) {
		RasterizerStorageGLES3::RenderTarget * rt = storage->render_target_owner.getornull(p_render_target);
		if (!rt) {
			storage->frame.current_rt=NULL;
		}
		ERR_FAIL_COND(!rt);
		storage->frame.current_rt=rt;
		storage->frame.clear_request=false;

		glViewport(0,0,rt->width,rt->height);				

	} else {
		storage->frame.current_rt=NULL;
		storage->frame.clear_request=false;
		glViewport(0,0,OS::get_singleton()->get_window_size().width,OS::get_singleton()->get_window_size().height);
		glBindFramebuffer(GL_FRAMEBUFFER,RasterizerStorageGLES3::system_fbo);
	}
}

void RasterizerGLES3::restore_render_target() {

	ERR_FAIL_COND(storage->frame.current_rt==NULL);
	RasterizerStorageGLES3::RenderTarget * rt = storage->frame.current_rt;
	glBindFramebuffer(GL_FRAMEBUFFER,rt->fbo);
	glViewport(0,0,rt->width,rt->height);

}

void RasterizerGLES3::clear_render_target(const Color& p_color) {

	ERR_FAIL_COND(!storage->frame.current_rt);

	storage->frame.clear_request=true;
	storage->frame.clear_request_color=p_color;

}

void RasterizerGLES3::blit_render_target_to_screen(RID p_render_target,const Rect2& p_screen_rect,int p_screen){

	ERR_FAIL_COND( storage->frame.current_rt );

	RasterizerStorageGLES3::RenderTarget *rt = storage->render_target_owner.getornull(p_render_target);
	ERR_FAIL_COND(!rt);

	canvas->canvas_begin();
	glDisable(GL_BLEND);
	glBindFramebuffer(GL_FRAMEBUFFER,RasterizerStorageGLES3::system_fbo);
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D,rt->color);
	canvas->draw_generic_textured_rect(p_screen_rect,Rect2(0,0,1,-1));
	glBindTexture(GL_TEXTURE_2D,0);
	canvas->canvas_end();
}

void RasterizerGLES3::end_frame(){

#if 0
	canvas->canvas_begin();
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D,storage->resources.white_tex);
	glDisable(GL_BLEND);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_CULL_FACE);


	float vtx[8]={0,0,
	0,1,
	1,1,
	1,0
	};

	glBindBuffer(GL_ARRAY_BUFFER,0);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,0);

	glEnableVertexAttribArray(VS::ARRAY_VERTEX);
	glVertexAttribPointer( VS::ARRAY_VERTEX, 2 ,GL_FLOAT, false, 0, vtx );


	//glBindBuffer(GL_ARRAY_BUFFER,canvas->data.canvas_quad_vertices);
	//glEnableVertexAttribArray(VS::ARRAY_VERTEX);
	//glVertexAttribPointer( VS::ARRAY_VERTEX, 2 ,GL_FLOAT, false, 0, 0 );

	glBindVertexArray(canvas->data.canvas_quad_array);

	canvas->draw_generic_textured_rect(Rect2(0,0,15,15),Rect2(0,0,1,1));
#endif
	OS::get_singleton()->swap_buffers();

/*	print_line("objects: "+itos(storage->info.render_object_count));
	print_line("material chages: "+itos(storage->info.render_material_switch_count));
	print_line("surface changes: "+itos(storage->info.render_surface_switch_count));
	print_line("shader changes: "+itos(storage->info.render_shader_rebind_count));
	print_line("vertices: "+itos(storage->info.render_vertices_count));
*/
}

void RasterizerGLES3::finalize(){

	storage->finalize();
	canvas->finalize();
}


Rasterizer *RasterizerGLES3::_create_current() {

	return memnew( RasterizerGLES3 );
}

void RasterizerGLES3::make_current() {
	_create_func=_create_current;
}


void RasterizerGLES3::register_config() {

	GLOBAL_DEF("rendering/gles3/render_architecture",0);
	GlobalConfig::get_singleton()->set_custom_property_info("rendering/gles3/render_architecture",PropertyInfo(Variant::INT,"",PROPERTY_HINT_ENUM,"Desktop,Mobile"));
	GLOBAL_DEF("rendering/quality/use_nearest_mipmap_filter",false);
	GLOBAL_DEF("rendering/quality/anisotropic_filter_level",4.0);

}

RasterizerGLES3::RasterizerGLES3()
{

	storage = memnew( RasterizerStorageGLES3 );
	canvas = memnew( RasterizerCanvasGLES3 );
	scene = memnew( RasterizerSceneGLES3 );
	canvas->storage=storage;
	storage->canvas=canvas;
	scene->storage=storage;
	storage->scene=scene;



}

RasterizerGLES3::~RasterizerGLES3() {

	memdelete(storage);
	memdelete(canvas);
}