#ifndef Magnum_GL_Version_h
#define Magnum_GL_Version_h
/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019
              Vladimír Vondruš <mosra@centrum.cz>

    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the "Software"),
    to deal in the Software without restriction, including without limitation
    the rights to use, copy, modify, merge, publish, distribute, sublicense,
    and/or sell copies of the Software, and to permit persons to whom the
    Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
    DEALINGS IN THE SOFTWARE.
*/

/** @file
 * @brief Enum @ref Magnum::GL::Version, function @ref Magnum::GL::version(), @ref Magnum::GL::isVersionES()
 */

#include <utility>

#include "Magnum/Magnum.h"
#include "Magnum/GL/visibility.h"

namespace Magnum { namespace GL {

#ifndef MAGNUM_TARGET_GLES
namespace Implementation {
    enum: Int { VersionESMask = 0x10000 };
}
#endif

/**
@brief OpenGL version

@see @ref version(), @ref Context, @ref MAGNUM_ASSERT_GL_VERSION_SUPPORTED()
*/
enum class Version: Int {
    None = 0xFFFF,                  /**< Unspecified */
    #ifndef MAGNUM_TARGET_GLES
    GL210 = 210,                    /**< OpenGL 2.1 / GLSL 1.20 */
    GL300 = 300,                    /**< OpenGL 3.0 / GLSL 1.30 */
    GL310 = 310,                    /**< OpenGL 3.1 / GLSL 1.40 */
    GL320 = 320,                    /**< OpenGL 3.2 / GLSL 1.50 */
    GL330 = 330,                    /**< OpenGL 3.3, GLSL 3.30 */
    GL400 = 400,                    /**< OpenGL 4.0, GLSL 4.00 */
    GL410 = 410,                    /**< OpenGL 4.1, GLSL 4.10 */
    GL420 = 420,                    /**< OpenGL 4.2, GLSL 4.20 */
    GL430 = 430,                    /**< OpenGL 4.3, GLSL 4.30 */
    GL440 = 440,                    /**< OpenGL 4.4, GLSL 4.40 */
    GL450 = 450,                    /**< OpenGL 4.5, GLSL 4.50 */
    GL460 = 460,                    /**< OpenGL 4.6, GLSL 4.60 */
    #endif

    /**
     * OpenGL ES 2.0 or WebGL 1.0, GLSL ES 1.00.
     *
     * On desktop OpenGL, all related functionality is present in extension
     * @gl_extension{ARB,ES2_compatibility} (OpenGL 4.1), so testing for this
     * version using @ref Context::isVersionSupported() is equivalent to
     * testing for availability of that extension.
     */
    #ifndef MAGNUM_TARGET_GLES
    GLES200 = Implementation::VersionESMask|200,
    #else
    GLES200 = 200,
    #endif

    /**
     * OpenGL ES 3.0 or WebGL 2.0, GLSL ES 3.00.
     *
     * On desktop OpenGL, all related functionality is present in extension
     * @gl_extension{ARB,ES3_compatibility} (OpenGL 4.3), so testing for this
     * version using @ref Context::isVersionSupported() is equivalent to
     * testing for availability of that extension.
     */
    #ifndef MAGNUM_TARGET_GLES
    GLES300 = Implementation::VersionESMask|300,
    #else
    GLES300 = 300,
    #endif

    #ifndef MAGNUM_TARGET_WEBGL
    /**
     * OpenGL ES 3.1, GLSL ES 3.10.
     *
     * On desktop OpenGL, all related functionality is present in extension
     * @gl_extension{ARB,ES3_1_compatibility} (OpenGL 4.5), so testing for this
     * version using @ref Context::isVersionSupported() is equivalent to
     * testing for availability of that extension.
     */
    #ifndef MAGNUM_TARGET_GLES
    GLES310 = Implementation::VersionESMask|310,
    #else
    GLES310 = 310,
    #endif
    #endif

    #ifndef MAGNUM_TARGET_WEBGL
    /**
     * OpenGL ES 3.2, GLSL ES 3.20.
     *
     * On desktop OpenGL, all related functionality is present in extension
     * @gl_extension{ARB,ES3_2_compatibility}, so testing for this version using
     * @ref Context::isVersionSupported() is equivalent to testing for
     * availability of that extension.
     */
    #ifndef MAGNUM_TARGET_GLES
    GLES320 = Implementation::VersionESMask|320,
    #else
    GLES320 = 320
    #endif
    #endif
};

/** @brief Enum value from major and minor version number */
constexpr Version version(Int major, Int minor) {
    return Version(major*100 + minor*10);
}

/**
@brief Major and minor version number from enum value

@see @ref isVersionES()
*/
inline std::pair<Int, Int> version(Version version) {
    const Int v = Int(version)
        #ifndef MAGNUM_TARGET_GLES
        & ~Implementation::VersionESMask
        #endif
        ;
    return {v/100, (v%100)/10};
}

/**
@brief Whether given version is OpenGL ES or WebGL

Always @cpp true @ce on @ref MAGNUM_TARGET_GLES "OpenGL ES" and WebGL build.
*/
#ifndef MAGNUM_TARGET_GLES
constexpr bool isVersionES(Version version) {
    return Int(version) & Implementation::VersionESMask;
}
#else
constexpr bool isVersionES(Version) { return true; }
#endif

/** @debugoperatorenum{Version} */
MAGNUM_GL_EXPORT Debug& operator<<(Debug& debug, Version value);

}}

#endif
