/*
    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>

    This file is part of Magnum.

    Magnum is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License version 3
    only, as published by the Free Software Foundation.

    Magnum 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 Lesser General Public License version 3 for more details.
*/

#include "VertexColorShader.h"

#include <Utility/Resource.h>

#include "Extensions.h"
#include "Shader.h"

namespace Magnum { namespace Shaders {

namespace {
    template<std::uint8_t dimensions> struct ShaderName {};

    template<> struct ShaderName<2> {
        constexpr static const char* vertex() { return "VertexColorShader2D.vert"; }
        constexpr static const char* fragment() { return "VertexColorShader2D.frag"; }
    };

    template<> struct ShaderName<3> {
        constexpr static const char* vertex() { return "VertexColorShader3D.vert"; }
        constexpr static const char* fragment() { return "VertexColorShader3D.frag"; }
    };
}

template<std::uint8_t dimensions> VertexColorShader<dimensions>::VertexColorShader() {
    Corrade::Utility::Resource rs("MagnumShaders");

    /* Weird bug in GCC 4.5 - cannot use initializer list here, although the
       same thing works in PhongShader flawlessly*/
    #ifndef CORRADE_GCC45_COMPATIBILITY
    #ifndef MAGNUM_TARGET_GLES
    Version v = Context::current()->supportedVersion({Version::GL320, Version::GL210});
    #else
    Version v = Context::current()->supportedVersion({Version::GLES300, Version::GLES200});
    #endif
    #else
    #ifndef MAGNUM_TARGET_GLES
    std::initializer_list<Version> vs{Version::GL320, Version::GL210};
    #else
    std::initializer_list<Version> vs{Version::GLES300, Version::GLES200};
    #endif
    Version v = Context::current()->supportedVersion(vs);
    #endif

    Shader vertexShader(v, Shader::Type::Vertex);
    vertexShader.addSource(rs.get("compatibility.glsl"));
    vertexShader.addSource(rs.get(ShaderName<dimensions>::vertex()));
    attachShader(vertexShader);

    Shader fragmentShader(v, Shader::Type::Fragment);
    fragmentShader.addSource(rs.get("compatibility.glsl"));
    fragmentShader.addSource(rs.get(ShaderName<dimensions>::fragment()));
    attachShader(fragmentShader);

    #ifndef MAGNUM_TARGET_GLES
    if(!Context::current()->isExtensionSupported<Extensions::GL::ARB::explicit_attrib_location>()) {
    #else
    if(!Context::current()->isVersionSupported(Version::GLES300)) {
    #endif
        bindAttributeLocation(Position::Location, "position");
        bindAttributeLocation(Color::Location, "color");
    }

    link();

    transformationProjectionMatrixUniform = uniformLocation("transformationProjectionMatrix");
}

template class VertexColorShader<2>;
template class VertexColorShader<3>;

}}