#include <GLFundamentals.hpp>
#include <GLDemonstration.hpp>
#include <obj.h>

class example : public gl::demonstration
{
    obj   *object;
    GLuint program;

    GLint ProjectionMatrixLocation;
    GLint ModelViewMatrixLocation;
    GLint NormalMatrixLocation;
    GLint LightPositionLocation;
    GLint AmbientLightLocation;

public:

    example();
    void draw();
};

example::example() : gl::demonstration("OBJ Demo", 960, 540), object(0), program(0)
{
    if ((program = gl::init_program("vertex.glsl", "fragment.glsl")))
    {
        glUseProgram(program);

        ProjectionMatrixLocation = glGetUniformLocation(program, "ProjectionMatrix");
        ModelViewMatrixLocation  = glGetUniformLocation(program, "ModelViewMatrix");
        NormalMatrixLocation     = glGetUniformLocation(program, "NormalMatrix");
        LightPositionLocation    = glGetUniformLocation(program, "LightPosition");
        AmbientLightLocation     = glGetUniformLocation(program, "AmbientLight");

        glUniform4f(AmbientLightLocation,  0.2, 0.2, 0.2, 1.0);

        if ((object = obj_create("Chest.obj")))
        {
            obj_set_vert_loc(object, glGetAttribLocation(program, "vTangent"),
                                     glGetAttribLocation(program, "vNormal"),
                                     glGetAttribLocation(program, "vTexCoord"),
                                     glGetAttribLocation(program, "vPosition"));

            obj_set_prop_loc(object, OBJ_KN, -1, glGetUniformLocation(program, "NormalTexture"), -1);
            obj_set_prop_loc(object, OBJ_KD, -1, glGetUniformLocation(program, "DiffuseTexture"), -1);
            obj_set_prop_loc(object, OBJ_KS, -1, glGetUniformLocation(program, "SpecularTexture"), -1);
        }
    }

    glClearColor(0.2, 0.2, 0.2, 0.0);
    glEnable(GL_DEPTH_TEST);

    cam_position = gl::vec3(0, 0, 3);
}

void example::draw()
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glUniformMatrix4fv(ProjectionMatrixLocation, 1, GL_TRUE, projection());
    glUniformMatrix4fv(ModelViewMatrixLocation,  1, GL_TRUE, view());
    glUniformMatrix3fv(NormalMatrixLocation,     1, GL_TRUE, normal(view()));
    glUniform4fv      (LightPositionLocation,    1,          light());

    if (object) obj_render(object);
}

int main(void)
{
    example demo;
    demo.run();
    return 0;
}