/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program 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 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2005 Blender Foundation.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): Brecht Van Lommel, Jason Wilkins.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file source/blender/gpu/intern/gpu_debug.c
 *  \ingroup gpu
 */

#include "BLI_utildefines.h"
#include "BLI_sys_types.h"
#include "BLI_system.h"

#include "BKE_global.h"

#include "GPU_glew.h"
#include "GPU_debug.h"
#include "intern/gpu_private.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* control whether we use older AMD_debug_output extension, or just the newer extensions
 * TODO(merwin): determine whether all supported GPU + OS combos have newer extensions */
#define LEGACY_DEBUG 0

/* Debug callbacks need the same calling convention as OpenGL functions. */
#if defined(_WIN32)
#   define APIENTRY __stdcall
#else
#   define APIENTRY
#endif


static const char* source_name(GLenum source)
{
	switch (source) {
		case GL_DEBUG_SOURCE_API: return "API";
		case GL_DEBUG_SOURCE_WINDOW_SYSTEM: return "window system";
		case GL_DEBUG_SOURCE_SHADER_COMPILER: return "shader compiler";
		case GL_DEBUG_SOURCE_THIRD_PARTY: return "3rd party";
		case GL_DEBUG_SOURCE_APPLICATION: return "application";
		case GL_DEBUG_SOURCE_OTHER: return "other";
		default: return "???";
	}
}

static const char* message_type_name(GLenum message)
{
	switch (message) {
		case GL_DEBUG_TYPE_ERROR: return "error";
		case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR: return "deprecated behavior";
		case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR: return "undefined behavior";
		case GL_DEBUG_TYPE_PORTABILITY: return "portability";
		case GL_DEBUG_TYPE_PERFORMANCE: return "performance";
		case GL_DEBUG_TYPE_OTHER: return "other";
		case GL_DEBUG_TYPE_MARKER: return "marker"; /* KHR has this, ARB does not */
		default: return "???";
	}
}

static void APIENTRY gpu_debug_proc(
        GLenum source, GLenum type, GLuint UNUSED(id),
        GLenum severity, GLsizei UNUSED(length),
        const GLchar *message, const GLvoid *UNUSED(userParm))
{
	bool backtrace = false;

	switch (severity) {
		case GL_DEBUG_SEVERITY_HIGH:
			backtrace = true;
			/* fall through */
		case GL_DEBUG_SEVERITY_MEDIUM:
		case GL_DEBUG_SEVERITY_LOW:
		case GL_DEBUG_SEVERITY_NOTIFICATION: /* KHR has this, ARB does not */
			fprintf(stderr, "GL %s %s: %s\n", source_name(source), message_type_name(type), message);
	}

	if (backtrace) {
		BLI_system_backtrace(stderr);
		fflush(stderr);
	}
}

#if LEGACY_DEBUG

static const char* category_name_amd(GLenum category)
{
	switch (category) {
		case GL_DEBUG_CATEGORY_API_ERROR_AMD: return "API error";
		case GL_DEBUG_CATEGORY_WINDOW_SYSTEM_AMD: return "window system";
		case GL_DEBUG_CATEGORY_DEPRECATION_AMD: return "deprecated behavior";
		case GL_DEBUG_CATEGORY_UNDEFINED_BEHAVIOR_AMD: return "undefined behavior";
		case GL_DEBUG_CATEGORY_PERFORMANCE_AMD: return "performance";
		case GL_DEBUG_CATEGORY_SHADER_COMPILER_AMD: return "shader compiler";
		case GL_DEBUG_CATEGORY_APPLICATION_AMD: return "application";
		case GL_DEBUG_CATEGORY_OTHER_AMD: return "other";
		default: return "???";
	}
}

static void APIENTRY gpu_debug_proc_amd(
        GLuint UNUSED(id), GLenum category,
        GLenum severity, GLsizei UNUSED(length),
        const GLchar *message,  GLvoid *UNUSED(userParm))
{
	bool backtrace = false;

	switch (severity) {
		case GL_DEBUG_SEVERITY_HIGH:
			backtrace = true;
			/* fall through */
		case GL_DEBUG_SEVERITY_MEDIUM:
		case GL_DEBUG_SEVERITY_LOW:
			fprintf(stderr, "GL %s: %s\n", category_name_amd(category), message);
	}

	if (backtrace) {
		BLI_system_backtrace(stderr);
		fflush(stderr);
	}
}
#endif /* LEGACY_DEBUG */

#undef APIENTRY

void gpu_debug_init(void)
{
	const char success[] = "Successfully hooked OpenGL debug callback.";

	if (GLEW_VERSION_4_3 || GLEW_KHR_debug) {
		fprintf(stderr, "Using %s\n", GLEW_VERSION_4_3 ? "OpenGL 4.3 debug facilities" : "KHR_debug extension");
		glEnable(GL_DEBUG_OUTPUT);
		glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
		glDebugMessageCallback((GLDEBUGPROC)gpu_debug_proc, mxGetCurrentContext());
		glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, NULL, GL_TRUE);
		GPU_string_marker(success);
	}
	else if (GLEW_ARB_debug_output) {
		fprintf(stderr, "Using ARB_debug_output extension\n");
		glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
		glDebugMessageCallbackARB((GLDEBUGPROCARB)gpu_debug_proc, mxGetCurrentContext());
		glDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, NULL, GL_TRUE);
		GPU_string_marker(success);
	}
#if LEGACY_DEBUG
	else if (GLEW_AMD_debug_output) {
		fprintf(stderr, "Using AMD_debug_output extension\n");
		glDebugMessageCallbackAMD(gpu_debug_proc_amd, mxGetCurrentContext());
		glDebugMessageEnableAMD(GL_DONT_CARE, GL_DONT_CARE, 0, NULL, GL_TRUE);
		GPU_string_marker(success);
	}
#endif
	else {
		fprintf(stderr, "Failed to hook OpenGL debug callback.\n");
	}
}


void gpu_debug_exit(void)
{
	if (GLEW_VERSION_4_3 || GLEW_KHR_debug) {
		glDebugMessageCallback(NULL, NULL);
	}
	else if (GLEW_ARB_debug_output) {
		glDebugMessageCallbackARB(NULL, NULL);
	}
#if LEGACY_DEBUG
	else if (GLEW_AMD_debug_output) {
		glDebugMessageCallbackAMD(NULL, NULL);
	}
#endif
}

void GPU_string_marker(const char *buf)
{
	if (GLEW_VERSION_4_3 || GLEW_KHR_debug) {
		glDebugMessageInsert(
		        GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_MARKER, 0,
		        GL_DEBUG_SEVERITY_NOTIFICATION, -1, buf);
	}
	else if (GLEW_ARB_debug_output) {
		glDebugMessageInsertARB(
		        GL_DEBUG_SOURCE_APPLICATION_ARB, GL_DEBUG_TYPE_OTHER_ARB, 0,
		        GL_DEBUG_SEVERITY_LOW_ARB, -1, buf);
	}
#if LEGACY_DEBUG
	else if (GLEW_AMD_debug_output) {
		glDebugMessageInsertAMD(
		        GL_DEBUG_CATEGORY_APPLICATION_AMD, GL_DEBUG_SEVERITY_LOW_AMD, 0,
		        0, buf);
	}
#endif
}

void GPU_print_error_debug(const char *str)
{
	if (G.debug & G_DEBUG)
		fprintf(stderr, "GPU: %s\n", str);
}