char Shader::vertex[] =
    "\n"
    "#version 120\n"
    "\n"
    "attribute vec4 InPosition;"
    "attribute vec3 InNormal;"
    "attribute vec4 InMaterialAmbient;"
    "uniform mat4 cl_ModelViewMatrix;"
    "uniform mat4 cl_ModelViewProjectionMatrix;"
    "uniform mat3 cl_NormalMatrix;"
    "varying vec3 WorldSpaceNormal; \n"
    "varying vec3 WorldSpacePosition; \n"
    "varying vec3 ObjPos;\n"
    "varying vec4 MaterialAmbient;\n"
    "\n"
    "void main()\n"
    "{\n"
    "   gl_Position = cl_ModelViewProjectionMatrix * InPosition;\n"
    "   WorldSpaceNormal = normalize( cl_NormalMatrix * InNormal );\n"
    "   WorldSpacePosition = InPosition.xyz;\n"
    "   MaterialAmbient = InMaterialAmbient;\n"
    "   ObjPos = vec3(cl_ModelViewMatrix * InPosition);\n"
    "}\n"
    ;

char Shader::fragment[] =
    "\n"
    "#version 120\n"
    "\n"
    "varying vec3 WorldSpaceNormal; \n"
    "varying vec3 WorldSpacePosition; \n"
    "varying vec3 ObjPos;\n"
    "varying vec4 MaterialAmbient;\n"
    "\n"
    "uniform float MaterialShininess;\n"
    "uniform vec4 MaterialEmission;\n"
    "uniform vec4 MaterialSpecular;\n"
    "\n"
    "uniform vec4 LightPosition;\n"
    "uniform vec4 LightHalfVector;\n"
    "uniform vec4 LightSpecular;\n"
    "uniform vec4 LightDiffuse;\n"
    "\n"
    "void main()\n"
    "{\n"
    "   vec3 texture_color = MaterialAmbient.rgb;\n"
    "\n"
    "   vec3 eye = -normalize(ObjPos); \n"
    "   vec4 diff = vec4(0); \n"
    "   vec4 spec = vec4(0); \n"
    "\n"
    "   float nDotL = max(0.0, dot(WorldSpaceNormal, LightPosition.xyz)); \n"
    "   float pf; \n"
    "   if (nDotL == 0.0)\n"
    "   {\n"
    "       pf = 0.0; \n"
    "   }else\n"
    "   {\n"
    "           float nDotHV = max(0.0, dot(WorldSpaceNormal, LightHalfVector.xyz));\n"
    "           pf = pow(nDotHV, MaterialShininess);\n"
    "   }\n"
    "   \n"
    "   spec += LightSpecular * pf; \n"
    "   diff += LightDiffuse * nDotL;\n"
    "\n"
    "   vec4 final_texture_color = vec4(texture_color,1.0);\n"
    "\n"
    "   const vec4 ambient_light = vec4(0.05, 0.05, 0.05, 1.0);\n"
    "   gl_FragColor = ambient_light * final_texture_color + (diff + MaterialEmission) * final_texture_color +spec * MaterialSpecular;\n"
    "\n"
    "   gl_FragColor.a = MaterialAmbient.a;\n"

    "}\n"
    ;

Shader::Shader(CL_GraphicContext &gc)
{
    CL_ShaderObject vertex_shader(gc, cl_shadertype_vertex, vertex);
    if(!vertex_shader.compile())
    {
        throw CL_Exception(cl_format("Unable to compile vertex shader object: %1", vertex_shader.get_info_log()));
    }

    CL_ShaderObject fragment_shader(gc, cl_shadertype_fragment, fragment);
    if(!fragment_shader.compile())
    {
        throw CL_Exception(cl_format("Unable to compile fragment shader object: %1", fragment_shader.get_info_log()));
    }

    program_object = CL_ProgramObject(gc);
    program_object.attach(vertex_shader);
    program_object.attach(fragment_shader);
    program_object.bind_attribute_location(0, "InPosition");
    program_object.bind_attribute_location(1, "InNormal");
    program_object.bind_attribute_location(2, "InMaterialAmbient");
    if (!program_object.link())
    {
        throw CL_Exception(cl_format("Unable to link program object: %1", program_object.get_info_log()));
    }

    material_shininess = 64.0f;
    material_emission = CL_Vec4f(0.0f, 0.0f, 0.0f, 1.0f);
    //material_ambient =  CL_Vec4f(0.9f, 0.2f, 0.2f, 1.0f);
    material_specular = CL_Vec4f(0.0f, 0.0f, 0.0f, 1.0f);

    light_position = CL_Vec4f(0.0f, 0.0f, 1.0f, 0.0f);
    light_specular = CL_Vec4f(0.7f, 0.7f, 0.7f, 1.0f);
    light_diffuse = CL_Vec4f(0.7f, 0.7f, 0.7f, 1.0f);


}

void Shader::Set(CL_GraphicContext &gc)
{
        program_object.set_uniform1f("MaterialShininess", material_shininess);
        program_object.set_uniform4f("MaterialEmission", material_emission);
        program_object.set_uniform4f("MaterialSpecular", material_specular);
        //program_object.set_uniform4f("MaterialAmbient", material_ambient);
        program_object.set_uniform4f("LightPosition", light_position);
        CL_Vec4f light_halfvector(0.0f, 0.0f, 1.0f, 0.0f);
        light_halfvector += light_position;
        light_halfvector.normalize3();
        program_object.set_uniform4f("LightHalfVector", light_halfvector);
        program_object.set_uniform4f("LightSpecular", light_specular);
        program_object.set_uniform4f("LightDiffuse", light_diffuse);
}

void Shader::Use(CL_GraphicContext &gc)
{
    gc.set_program_object(program_object);
}