#include "wx/wx.h"
#include "wx/sizer.h"
#include "wx/glcanvas.h"

#include "basic_gl_pane.h"
#include "image.h"
#include "drawable.h"

// include OpenGL
#ifdef __WXMAC__
#include "OpenGL/glu.h"
#include "OpenGL/gl.h"
#else
#include <GL/glu.h>
#include <GL/gl.h>
#endif

class MyApp: public wxApp
{
    virtual bool OnInit();

    wxFrame *frame;
    BasicGLPane * glPane;
public:

};

IMPLEMENT_APP(MyApp)

Image* image = NULL;
DrawableThing* sprite;

bool MyApp::OnInit()
{
    wxBoxSizer* sizer = new wxBoxSizer(wxHORIZONTAL);
    frame = new wxFrame((wxFrame *)NULL, -1, char_to_wx("Hello GL World"), wxPoint(50,50), wxSize(400,200));

    int args[] = {WX_GL_RGBA, WX_GL_DOUBLEBUFFER, WX_GL_DEPTH_SIZE, 16, 0};

    glPane = new BasicGLPane( (wxFrame*) frame, args);
    sizer->Add(glPane, 1, wxEXPAND);

    frame->SetSizer(sizer);
    frame->SetAutoLayout(true);

    frame->Show();
    return true;
}

BEGIN_EVENT_TABLE(BasicGLPane, wxGLCanvas)
EVT_MOTION(BasicGLPane::mouseMoved)
EVT_LEFT_DOWN(BasicGLPane::mouseDown)
EVT_LEFT_UP(BasicGLPane::mouseReleased)
EVT_RIGHT_DOWN(BasicGLPane::rightClick)
EVT_LEAVE_WINDOW(BasicGLPane::mouseLeftWindow)
EVT_SIZE(BasicGLPane::resized)
EVT_KEY_DOWN(BasicGLPane::keyPressed)
EVT_KEY_UP(BasicGLPane::keyReleased)
EVT_MOUSEWHEEL(BasicGLPane::mouseWheelMoved)
EVT_PAINT(BasicGLPane::render)
END_EVENT_TABLE()


// some useful events to use
void BasicGLPane::mouseMoved(wxMouseEvent& event) {}
void BasicGLPane::mouseDown(wxMouseEvent& event) {}
void BasicGLPane::mouseWheelMoved(wxMouseEvent& event) {}
void BasicGLPane::mouseReleased(wxMouseEvent& event) {}
void BasicGLPane::rightClick(wxMouseEvent& event) {}
void BasicGLPane::mouseLeftWindow(wxMouseEvent& event) {}
void BasicGLPane::keyPressed(wxKeyEvent& event) {}
void BasicGLPane::keyReleased(wxKeyEvent& event) {}

BasicGLPane::BasicGLPane(wxFrame* parent, int* args) :
wxGLCanvas(parent, wxID_ANY,  wxDefaultPosition, wxDefaultSize, 0, char_to_wx("GLCanvas"),  args)
{
}

void BasicGLPane::resized(wxSizeEvent& evt)
{
    wxGLCanvas::OnSize(evt);

    Refresh();
}

void BasicGLPane::prepare3DViewport(int topleft_x, int topleft_y, int bottomrigth_x, int bottomrigth_y)
{
    /*
     *  Inits the OpenGL viewport for drawing in 3D.
     */

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Black Background
    glClearDepth(1.0f);	// Depth Buffer Setup
    glEnable(GL_DEPTH_TEST); // Enables Depth Testing
    glDepthFunc(GL_LEQUAL); // The Type Of Depth Testing To Do
    glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

    glEnable(GL_COLOR_MATERIAL);

    glViewport(topleft_x, topleft_y, bottomrigth_x-topleft_x, bottomrigth_y-topleft_y);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    float ratio_w_h = (float)(bottomrigth_x-topleft_x)/(float)(bottomrigth_y-topleft_y);
    gluPerspective(45 /*view angle*/, ratio_w_h, 0.1 /*clip close*/, 200 /*clip far*/);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

}

void BasicGLPane::prepare2DViewport(int topleft_x, int topleft_y, int bottomrigth_x, int bottomrigth_y)
{

    /*
     *  Inits the OpenGL viewport for drawing in 2D
     */

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Black Background
    glEnable(GL_TEXTURE_2D);   // textures
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_BLEND);
    glDisable(GL_DEPTH_TEST);
    glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);

    glViewport(topleft_x, topleft_y, bottomrigth_x-topleft_x, bottomrigth_y-topleft_y);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    gluOrtho2D(topleft_x, bottomrigth_x, bottomrigth_y, topleft_y);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}

int BasicGLPane::getWidth()
{
    return GetSize().x;
}

int BasicGLPane::getHeight()
{
    return GetSize().y;
}

void BasicGLPane::render( wxPaintEvent& evt )
{
    if(!IsShown()) return;

    wxGLCanvas::SetCurrent();


    if(image == NULL)
    {
        image = new Image(char_to_wx("myfile.png"));
        sprite = new DrawableThing(image);
    }

    wxPaintDC(this); // only to be used in paint events. use wxClientDC to paint outside the paint event

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    // render loaded image
    prepare2DViewport(0,0,getWidth(), getHeight());
    sprite->render();

    glFlush();
    SwapBuffers();
}