#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

#include "SDL.h"
#include "SDL_opengl.h"

static SDL_Surface *global_image = NULL;
static GLuint global_texture = 0;

#include "util.h"
#include "entity.h"
#include "txtprt_import.h"

CGcontext cgc;
CGprogram vsh, fsh;
CGparameter mv, mvp, lightpos;
CGprofile vsh_profile, fsh_profile;

static void CheckCgError(void)
{
  CGerror err = cgGetError();

  if (err != CG_NO_ERROR)
   {
     printf("CG error: %s\n", cgGetErrorString(err));
     exit(1);
   }
}

/**********************************************************************/

view camera;
vec3 camera_velocity;
float camera_velocity_factor = 20;

void
HotKey_ToggleFullScreen (void)
{
  SDL_Surface *screen;

  screen = SDL_GetVideoSurface ();
  if (SDL_WM_ToggleFullScreen (screen))
    printf ("Toggled fullscreen mode - now %s\n",
            (screen->flags & SDL_FULLSCREEN) ? "fullscreen" : "windowed");
  else
    printf ("Unable to toggle fullscreen mode\n");
}

void
HotKey_ToggleGrab (void)
{
  SDL_GrabMode mode;

  printf ("Ctrl-G: toggling input grab!\n");
  mode = SDL_WM_GrabInput (SDL_GRAB_QUERY);
  if (mode == SDL_GRAB_ON)
    printf ("Grab was on\n");
  else
    printf ("Grab was off\n");

  mode = SDL_WM_GrabInput (mode ? SDL_GRAB_OFF : SDL_GRAB_ON);
  if (mode == SDL_GRAB_ON)
    printf ("Grab is now on\n");
  else
    printf ("Grab is now off\n");
}

void
HotKey_Iconify (void)
{
  printf ("Ctrl-Z: iconifying window!\n");
  SDL_WM_IconifyWindow ();
}

int
HandleEvent (SDL_Event * event)
{
  int done;

  done = 0;
  switch (event->type)
    {
    case SDL_ACTIVEEVENT:
      /* See what happened */
      printf ("app %s ", event->active.gain ? "gained" : "lost");
      if (event->active.state & SDL_APPACTIVE)
	{
	  printf ("active ");
	}
      else if (event->active.state & SDL_APPMOUSEFOCUS)
	{
	  printf ("mouse ");
	}
      else if (event->active.state & SDL_APPINPUTFOCUS)
	{
	  printf ("input ");
	}

      printf ("focus\n");
      break;

    case SDL_KEYDOWN:
      if (event->key.keysym.sym == SDLK_UP)    camera_velocity.z--;
      if (event->key.keysym.sym == SDLK_DOWN)  camera_velocity.z++;
      if (event->key.keysym.sym == SDLK_LEFT)  camera_velocity.x--;
      if (event->key.keysym.sym == SDLK_RIGHT) camera_velocity.x++;
      if (event->key.keysym.sym == SDLK_a)     camera_velocity.y--;
      if (event->key.keysym.sym == SDLK_s)     camera_velocity.y++;
      if (event->key.keysym.sym == SDLK_v)     camera_velocity_factor *= 1.5;
      if (event->key.keysym.sym == SDLK_b)     camera_velocity_factor /= 1.5;

      if (event->key.keysym.sym == SDLK_ESCAPE)
	done = 1;

      if ((event->key.keysym.sym == SDLK_g) &&
	  (event->key.keysym.mod & KMOD_CTRL))
	HotKey_ToggleGrab ();

      if ((event->key.keysym.sym == SDLK_z) &&
	  (event->key.keysym.mod & KMOD_CTRL))
	HotKey_Iconify ();

      if ((event->key.keysym.sym == SDLK_RETURN) &&
	  (event->key.keysym.mod & KMOD_ALT))
	HotKey_ToggleFullScreen ();

      break;

    case SDL_KEYUP:
      if (event->key.keysym.sym == SDLK_UP)    camera_velocity.z++;
      if (event->key.keysym.sym == SDLK_DOWN)  camera_velocity.z--;
      if (event->key.keysym.sym == SDLK_LEFT)  camera_velocity.x++;
      if (event->key.keysym.sym == SDLK_RIGHT) camera_velocity.x--;
      if (event->key.keysym.sym == SDLK_a)     camera_velocity.y++;
      if (event->key.keysym.sym == SDLK_s)     camera_velocity.y--;
      break;

    case SDL_QUIT:
      done = 1;
      break;
    }

  return (done);
}

int
RunGLTest (int argc, char *argv[],
	   int logo, int slowly, int bpp, float gamma, int noframe, int fsaa)
{
  int i;
  int rgb_size[3];
  int w = 640;
  int h = 480;
  int done = 0;
  int frames;
  Uint32 start_time, this_time;
  Uint32 video_flags;
  int value;

  if (SDL_Init (SDL_INIT_VIDEO) < 0)
    {
      fprintf (stderr, "Couldn't initialize SDL: %s\n", SDL_GetError ());
      exit (1);
    }

  /* See if we should detect the display depth */
  if (bpp == 0)
    {
      if (SDL_GetVideoInfo ()->vfmt->BitsPerPixel <= 8)
	bpp = 8;
      else
	bpp = 16;		/* More doesn't seem to work */
    }

  video_flags = SDL_OPENGL;

  for (i = 1; argv[i]; ++i)
    if (strcmp (argv[1], "-fullscreen") == 0)
      video_flags |= SDL_FULLSCREEN;

  if (noframe)
    video_flags |= SDL_NOFRAME;

  /* Initialize the display */
  switch (bpp)
    {
    case 8:
      rgb_size[0] = 3;
      rgb_size[1] = 3;
      rgb_size[2] = 2;
      break;

    case 15:
    case 16:
      rgb_size[0] = 5;
      rgb_size[1] = 5;
      rgb_size[2] = 5;
      break;

    default:
      rgb_size[0] = 8;
      rgb_size[1] = 8;
      rgb_size[2] = 8;
      break;
    }

  SDL_GL_SetAttribute (SDL_GL_RED_SIZE, rgb_size[0]);
  SDL_GL_SetAttribute (SDL_GL_GREEN_SIZE, rgb_size[1]);
  SDL_GL_SetAttribute (SDL_GL_BLUE_SIZE, rgb_size[2]);
  SDL_GL_SetAttribute (SDL_GL_DEPTH_SIZE, 16);
  SDL_GL_SetAttribute (SDL_GL_DOUBLEBUFFER, 1);

  if (fsaa)
    {
      SDL_GL_SetAttribute (SDL_GL_MULTISAMPLEBUFFERS, 1);
      SDL_GL_SetAttribute (SDL_GL_MULTISAMPLESAMPLES, fsaa);
    }

  if (SDL_SetVideoMode (w, h, bpp, video_flags) == NULL)
    {
      fprintf (stderr, "Couldn't set GL mode: %s\n", SDL_GetError ());
      SDL_Quit ();
      exit (1);
    }

  printf ("Screen BPP: %d\n", SDL_GetVideoSurface ()->format->BitsPerPixel);
  printf ("\n");
  printf ("Vendor     : %s\n", glGetString (GL_VENDOR));
  printf ("Renderer   : %s\n", glGetString (GL_RENDERER));
  printf ("Version    : %s\n", glGetString (GL_VERSION));
  printf ("Extensions : %s\n", glGetString (GL_EXTENSIONS));
  printf ("\n");

  SDL_GL_GetAttribute (SDL_GL_RED_SIZE, &value);
  printf ("SDL_GL_RED_SIZE: requested %d, got %d\n", rgb_size[0], value);
  SDL_GL_GetAttribute (SDL_GL_GREEN_SIZE, &value);
  printf ("SDL_GL_GREEN_SIZE: requested %d, got %d\n", rgb_size[1], value);
  SDL_GL_GetAttribute (SDL_GL_BLUE_SIZE, &value);
  printf ("SDL_GL_BLUE_SIZE: requested %d, got %d\n", rgb_size[2], value);
  SDL_GL_GetAttribute (SDL_GL_DEPTH_SIZE, &value);
  printf ("SDL_GL_DEPTH_SIZE: requested %d, got %d\n", bpp, value);
  SDL_GL_GetAttribute (SDL_GL_DOUBLEBUFFER, &value);
  printf ("SDL_GL_DOUBLEBUFFER: requested 1, got %d\n", value);

  if (fsaa)
    {
      SDL_GL_GetAttribute (SDL_GL_MULTISAMPLEBUFFERS, &value);
      printf ("SDL_GL_MULTISAMPLEBUFFERS: requested 1, got %d\n", value);
      SDL_GL_GetAttribute (SDL_GL_MULTISAMPLESAMPLES, &value);
      printf ("SDL_GL_MULTISAMPLESAMPLES: requested %d, got %d\n", fsaa,
	      value);
    }

  /* Set the window manager title bar */
  SDL_WM_SetCaption ("libgender rendering test", "gendertest");

  /* Set the gamma for the window */
  if (gamma != 0.0)
    SDL_SetGamma (gamma, gamma, gamma);

  // load a entity
  for (int i = 0; i < 7; i++)
    {
      txtprt_parser p;
      entity_transform *f = new entity_transform;
      entity *e;
      try
      {
        e = p.read ("test.blasc");
      } catch (txtprt_i_exception & e)
      {
        cout << "ERR: " << e.msg << endl;
      }
      f->set (e);
      f->update (matrix::translation (vec3 (0, -1, -i*5)));
      f->show ();
    }

  camera.orig.x = camera.orig.y = camera.orig.z = 0;
  camera.p = point (0, 0, 10);
  camera.d = vec3 (0, 0, -1);
  camera.u = vec3 (0, 1, 0);
  camera.w = w; camera.h = h;
  camera.fov = 90;

  glMatrixMode (GL_MODELVIEW);
  glLoadIdentity ();

  glEnable (GL_CULL_FACE);
  glEnable (GL_DEPTH_TEST);

  glShadeModel (GL_SMOOTH);

  glEnable (GL_LIGHTING);
  //GLfloat lightc[4] = { 1, 0.1, 0.1, 1 };
  //glLightf (GL_LIGHT0, GL_QUADRATIC_ATTENUATION);
  //glLightfv (GL_LIGHT0, GL_DIFFUSE, lightc);
  glEnable (GL_LIGHT0);

  cgc = cgCreateContext ();

  vsh_profile = CG_PROFILE_ARBVP1;
  //if (cgGLIsProfileSupported (CG_PROFILE_VP30)) vsh_profile = CG_PROFILE_VP30;
  //if (cgGLIsProfileSupported (CG_PROFILE_VP40)) vsh_profile = CG_PROFILE_VP40;
  fsh_profile = CG_PROFILE_ARBFP1;
  //if (cgGLIsProfileSupported (CG_PROFILE_FP30)) fsh_profile = CG_PROFILE_FP30;
  //if (cgGLIsProfileSupported (CG_PROFILE_FP40)) fsh_profile = CG_PROFILE_FP40;

  vsh = cgCreateProgramFromFile (cgc, CG_SOURCE, "vsh.cg", vsh_profile, 0, 0);
  CheckCgError ();
  cgGLLoadProgram (vsh);
  CheckCgError ();
  mv = cgGetNamedParameter (vsh, "WorldProj");
  mvp = cgGetNamedParameter (vsh, "WorldViewProj");
  lightpos = cgGetNamedParameter (vsh, "LightPos");
  CheckCgError ();

  fsh = cgCreateProgramFromFile (cgc, CG_SOURCE, "fsh.cg", fsh_profile, 0, 0);
  CheckCgError ();
  cgGLLoadProgram (fsh);
  CheckCgError ();

  cgGLBindProgram (vsh);
  CheckCgError ();
  cgGLBindProgram (fsh);
  CheckCgError ();

  /* Loop until done. */
  start_time = SDL_GetTicks ();
  frames = 0;

  while (!done)
    {
      GLenum gl_error;
      char *sdl_error;
      SDL_Event event;

      glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

      camera.p.x += (camera_velocity_factor * camera_velocity.x) * timer.diff;
      camera.p.y += (camera_velocity_factor * camera_velocity.y) * timer.diff;
      camera.p.z += (camera_velocity_factor * camera_velocity.z) * timer.diff;

      cgGLSetParameter4f (lightpos, camera.p.x, camera.p.y, camera.p.z, 1);

#if 0
      static GLfloat ry;
      ry += 0.001;
      camera.d.x = cos (ry);
      camera.d.z = sin (ry);
      //camera.d.y = sin (ry * 0.1);
#endif

      camera.begin ();
      camera.pass (view::DEPTH);
      camera.pass (view::LIGHTED);
      camera.end ();

      SDL_GL_SwapBuffers ();
      timer.frame ();

      /* Check for error conditions. */
      gl_error = glGetError ();

      if (gl_error != GL_NO_ERROR)
	fprintf (stderr, "testgl: OpenGL error: %d\n", gl_error);

      sdl_error = SDL_GetError ();

      if (sdl_error[0] != '\0')
	{
	  fprintf (stderr, "testgl: SDL error '%s'\n", sdl_error);
	  SDL_ClearError ();
	}

      /* Allow the user to see what's happening */
      //SDL_Delay (20);

      /* Check if there's a pending event. */
      while (SDL_PollEvent (&event))
	done = HandleEvent (&event);


      ++frames;
    }

  /* Print out the frames per second */
  this_time = SDL_GetTicks ();
  if (this_time != start_time)
    {
      printf ("%2.2f FPS\n",
	      ((float) frames / (this_time - start_time)) * 1000.0);
    }

  if (global_image)
    {
      SDL_FreeSurface (global_image);
      global_image = NULL;
    }
  if (global_texture)
    {
      glDeleteTextures (1, &global_texture);
      global_texture = 0;
    }

  /* Destroy our GL context, etc. */
  SDL_Quit ();
  return (0);
}

int
main (int argc, char *argv[])
{
  int i, logo;
  int numtests;
  int bpp = 0;
  int slowly;
  float gamma = 0.0;
  int noframe = 0;
  int fsaa = 0;

  logo = 0;
  slowly = 0;
  numtests = 1;
  for (i = 1; argv[i]; ++i)
    {
      if (strcmp (argv[i], "-twice") == 0)
	{
	  ++numtests;
	}
      if (strcmp (argv[i], "-slow") == 0)
	{
	  slowly = 1;
	}
      if (strcmp (argv[i], "-bpp") == 0)
	{
	  bpp = atoi (argv[++i]);
	}
      if (strcmp (argv[i], "-gamma") == 0)
	{
	  gamma = (float) atof (argv[++i]);
	}
      if (strcmp (argv[i], "-noframe") == 0)
	{
	  noframe = 1;
	}
      if (strcmp (argv[i], "-fsaa") == 0)
	{
	  ++fsaa;
	}
      if (strncmp (argv[i], "-h", 2) == 0)
	{
	  printf
	    ("Usage: %s [-twice] [-logo] [-slow] [-bpp n] [-gamma n] [-noframe] [-fsaa]\n",
	     argv[0]);
	  exit (0);
	}
    }

  for (i = 0; i < numtests; ++i)
    RunGLTest (argc, argv, logo, slowly, bpp, gamma, noframe, fsaa);

  return 0;
}