#if defined(__APPLE__)
#include <OpenGL/glu.h>
#include <OpenGL/OpenGL.h>
#include <OpenGL/CGLMacro.h>
#else
#include <GL/glu.h>
#endif

#include "plane.h"
#include "plane_cloud.h"

static GLuint _vertex_buffer_id;
static GLuint _index_buffer_id;

int initialize_naive_vbo_renderer(void)
{
#if defined(__APPLE__)
    CGLContextObj CGL_MACRO_CONTEXT = CGLGetCurrentContext();
#endif

    if (!gluCheckExtension(
        (const GLubyte*)"GL_ARB_vertex_buffer_object",
        glGetString(GL_EXTENSIONS)))
    {
        return 0;
    }

    glGenBuffersARB(1, &_vertex_buffer_id);
    if (_vertex_buffer_id == 0)
    {
        return 0;
    }
    glBindBufferARB(GL_ARRAY_BUFFER_ARB, _vertex_buffer_id);
    glBufferDataARB(
        GL_ARRAY_BUFFER_ARB,
        3 * sizeof(float) * PLANE_VERTEX_COUNT,
        PLANE_VERTICES,
        GL_STATIC_DRAW_ARB);
    glBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);
    
    glGenBuffersARB(1, &_index_buffer_id);
    if (_index_buffer_id == 0)
    {
        glDeleteBuffersARB(1, &_vertex_buffer_id);
        return 0;
    }
    glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, _index_buffer_id);
    glBufferDataARB(
        GL_ELEMENT_ARRAY_BUFFER_ARB,
        sizeof(unsigned) * PLANE_INDEX_COUNT,
        PLANE_INDICES,
        GL_STATIC_DRAW_ARB);
    glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);
    
    return 1;
}

void update_naive_vbo_rendererer(double dt)
{
#if defined(__APPLE__)
    CGLContextObj CGL_MACRO_CONTEXT = CGLGetCurrentContext();
#endif

    unsigned num_planes = plane_count();
    const float *matrices = plane_matrices();
    
    glBindBufferARB(GL_ARRAY_BUFFER_ARB, _vertex_buffer_id);
    glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, _index_buffer_id);

    glVertexPointer(3, GL_FLOAT, 0, 0);
    glEnableClientState(GL_VERTEX_ARRAY);
    
    unsigned i;
    const float *matrix = matrices;
    for (i = 0; i < num_planes; ++i)
    {
        glPushMatrix();
        glMultMatrixf(matrix);
        glDrawElements(
            GL_TRIANGLES, PLANE_INDEX_COUNT, GL_UNSIGNED_INT, 0);
        glPopMatrix();
        
        matrix += 16;
    }
    
    glDisableClientState(GL_VERTEX_ARRAY);
    glBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);
    glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);
}