/******************************************************************************#
#           guvcview              http://guvcview.sourceforge.net              #
#                                                                              #
#           Paulo Assis <pj.assis@gmail.com>                                   #
#           Nobuhiro Iwamatsu <iwamatsu@nigauri.org>                           #
#                             Add UYVY color support(Macbook iSight)           #
#           Flemming Frandsen <dren.dk@gmail.com>                              #
#                             Add VU meter OSD                                 #
#                                                                              #
# This program is free software; you can redistribute it and/or modify         #
# it under the terms of the GNU General Public License as published by         #
# the Free Software Foundation; either version 2 of the License, or            #
# (at your option) any later version.                                          #
#                                                                              #
# This program is distributed in the hope that it will be useful,              #
# but WITHOUT ANY WARRANTY; without even the implied warranty of               #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                #
# GNU General Public License for more details.                                 #
#                                                                              #
# You should have received a copy of the GNU General Public License            #
# along with this program; if not, write to the Free Software                  #
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA    #
#                                                                              #
*******************************************************************************/

#include "render_sfml.hpp"
#include <cstring>
#include <iostream>

extern "C" {
// #include "../config.h"
#include "gview.h"
#include "gviewrender.h"
#include "render_sfml.h"
}

extern int render_verbosity;

/*
 * yu12 to rgba (rgb32)
 * args:
 *    out - pointer to output rgba data buffer
 *    in - pointer to input yu12 data buffer
 *    width - buffer width (in pixels)
 *    height - buffer height (in pixels)
 *
 * asserts:
 *    none
 *
 * returns: none
 */
static void yu12_to_rgba(uint8_t *out, uint8_t *in, int width, int height) {
  uint8_t *py1 = in;          // line 1
  uint8_t *py2 = py1 + width; // line 2
  uint8_t *pu = in + (width * height);
  uint8_t *pv = pu + ((width * height) / 4);

  uint8_t *pout1 = out;               // first line
  uint8_t *pout2 = out + (width * 4); // second line

  int h = 0, w = 0;

  for (h = 0; h < height; h += 2) // every two lines
  {
    py1 = in + (h * width);
    py2 = py1 + width;

    pout1 = out + (h * width * 4);
    pout2 = pout1 + (width * 4);

    for (w = 0; w < width; w += 2) // every 2 pixels
    {
      /* standart: r = y0 + 1.402 (v-128) */
      /* logitech: r = y0 + 1.370705 (v-128) */
      *pout1++ = CLIP(*py1 + 1.402 * (*pv - 128));
      *pout2++ = CLIP(*py2 + 1.402 * (*pv - 128));
      /* standart: g = y0 - 0.34414 (u-128) - 0.71414 (v-128)*/
      /* logitech: g = y0 - 0.337633 (u-128)- 0.698001 (v-128)*/
      *pout1++ = CLIP(*py1 - 0.34414 * (*pu - 128) - 0.71414 * (*pv - 128));
      *pout2++ = CLIP(*py2 - 0.34414 * (*pu - 128) - 0.71414 * (*pv - 128));
      /* standart: b = y0 + 1.772 (u-128) */
      /* logitech: b = y0 + 1.732446 (u-128) */
      *pout1++ = CLIP(*py1 + 1.772 * (*pu - 128));
      *pout2++ = CLIP(*py2 + 1.772 * (*pu - 128));
      /* alpha set to 255*/
      *pout1++ = 255;
      *pout2++ = 255;

      py1++;
      py2++;

      /* standart: r1 =y1 + 1.402 (v-128) */
      /* logitech: r1 = y1 + 1.370705 (v-128) */
      *pout1++ = CLIP(*py1 + 1.402 * (*pv - 128));
      *pout2++ = CLIP(*py2 + 1.402 * (*pv - 128));
      /* standart: g1 = y1 - 0.34414 (u-128) - 0.71414 (v-128)*/
      /* logitech: g1 = y1 - 0.337633 (u-128)- 0.698001 (v-128)*/
      *pout1++ = CLIP(*py1 - 0.34414 * (*pu - 128) - 0.71414 * (*pv - 128));
      *pout2++ = CLIP(*py2 - 0.34414 * (*pu - 128) - 0.71414 * (*pv - 128));
      /* standart: b1 = y1 + 1.772 (u-128) */
      /* logitech: b1 = y1 + 1.732446 (u-128) */
      *pout1++ = CLIP(*py1 + 1.772 * (*pu - 128));
      *pout2++ = CLIP(*py2 + 1.772 * (*pu - 128));
      /* alpha set to 255*/
      *pout1++ = 255;
      *pout2++ = 255;

      py1++;
      py2++;
      pu++;
      pv++;
    }
  }
}

static sf::View getLetterboxView(sf::View view, int windowWidth, int windowHeight) {

    // Compares the aspect ratio of the window to the aspect ratio of the view,
    // and sets the view's viewport accordingly in order to achieve a letterbox effect.
    // A new view (with a new viewport set) is returned.

    float windowRatio = (float) windowWidth / (float) windowHeight;
    float viewRatio = view.getSize().x / (float) view.getSize().y;
    float sizeX = 1;
    float sizeY = 1;
    float posX = 0;
    float posY = 0;

    bool horizontalSpacing = true;
    if (windowRatio < viewRatio)
        horizontalSpacing = false;

    // If horizontalSpacing is true, the black bars will appear on the left and right side.
    // Otherwise, the black bars will appear on the top and bottom.

    if (horizontalSpacing) {
        sizeX = viewRatio / windowRatio;
        posX = (1 - sizeX) / 2.f;
    }

    else {
        sizeY = windowRatio / viewRatio;
        posY = (1 - sizeY) / 2.f;
    }

    view.setViewport( sf::FloatRect(posX, posY, sizeX, sizeY) );

    return view;
}

SFMLRender::SFMLRender(int width, int height, int flags, int win_w, int win_h) {
  int w = width;
  int h = height;

  if (win_w > 0)
    w = win_w;
  if (win_h > 0)
    h = win_h;

  use_shader = true;

  pix = NULL;

  // get the current resolution
  sf::VideoMode display_mode = sf::VideoMode::getDesktopMode();

  if (render_verbosity > 0)
    std::cout << "RENDER: (SFML) desktop resolution (" << display_mode.width
              << "x" << display_mode.height << ")" << std::endl;

  if ((display_mode.width > 0) && (display_mode.height > 0)) {
    if (w > display_mode.width)
      w = display_mode.width;
    if (h > display_mode.height)
      h = display_mode.height;
  }

  // Create the main window
  if (flags == 1) // fullscreen
  {
    window.create(sf::VideoMode(w, h), "SFML window", sf::Style::Fullscreen);
    if (!window.isOpen()) {
      std::cerr << "RENDER: (SFML) couldn't open window in fullscreen mode"
                << std::endl;
      window.create(sf::VideoMode(w, h), "SFML window", sf::Style::Resize);
    }
  } else
    window.create(sf::VideoMode(w, h), "SFML window", sf::Style::Resize);

  if (!window.isOpen()) {
    std::cerr << "RENDER: (SFML) couldn't open window" << std::endl;
    return;
  }

  if (!texture.create(width, height)) {
    std::cerr << "RENDER: (SFML) couldn't create texture" << std::endl;
    return;
  }

  if (sf::Shader::isAvailable()) {
    const std::string fragmentShader =
        "uniform sampler2D texY;"
        "uniform sampler2D texU;"
        "uniform sampler2D texV;"
        "void main(void)"
        "{"
        "float nx, ny;"
        "vec3 yuv;"
        "vec3 rgb;"
        "vec2 norm_pos = vec2( gl_TexCoord[0].x,gl_TexCoord[0].y);"
        "yuv.x = texture2D(texY, norm_pos).r;"
        "yuv.y = texture2D(texU, norm_pos).r - 0.5;"
        "yuv.z = texture2D(texV, norm_pos).r - 0.5;"
        "rgb = mat3(      1,       1,       1,"
        "                 0, -.21482, 2.12798,"
        "           1.28033, -.38059,       0) * yuv;"
        "gl_FragColor = vec4(rgb, 1.0);"
        "}";

    if (!conv_yuv2rgb_shd.loadFromMemory(fragmentShader,
                                         sf::Shader::Fragment)) {
      std::cerr
          << "RENDER: (SFML) couldn't load fragment shader for yuv conversion"
          << std::endl;
      use_shader = false;
    } else {
      if (!texY.create(width, height)) {
        std::cerr << "RENDER: (SFML) couldn't create texture" << std::endl;
        return;
      }

      if (!texU.create(width / 2, height / 2)) {
        std::cerr << "RENDER: (SFML) couldn't create texture" << std::endl;
        return;
      }

      if (!texV.create(width / 2, height / 2)) {
        std::cerr << "RENDER: (SFML) couldn't create texture" << std::endl;
        return;
      }

#if LIBSFML_VER_AT_LEAST(2, 4)
      conv_yuv2rgb_shd.setUniform("texY", texY);
      conv_yuv2rgb_shd.setUniform("texU", texU);
      conv_yuv2rgb_shd.setUniform("texV", texV);
#else
      conv_yuv2rgb_shd.setParameter("texY", texY);
      conv_yuv2rgb_shd.setParameter("texU", texU);
      conv_yuv2rgb_shd.setParameter("texV", texV);
#endif
    }
  } else {
    std::cerr << "RENDER: (SFML) shader not available for yuv conversion"
              << std::endl;
    use_shader = false;
  }

  // use pix buffer for rgba conversion
  if (!use_shader)
    pix = (uint8_t *)calloc(width * height * 4, sizeof(uint8_t));

  sprite.setTexture(texture);

  texture.setSmooth(true);

  sf::View view;
  view.setSize( width, height );
  view.setCenter( view.getSize().x / 2, view.getSize().y / 2 );
  view = getLetterboxView( view, w, h );
  
  window.setView(view);
  window.clear(sf::Color::Black);
  window.display();

  if (render_verbosity > 1)
    std::cout << "RENDER: (SFML) window created" << std::endl;
}

SFMLRender::~SFMLRender() {

  if (pix)
    free(pix);

  window.close();
}

int SFMLRender::render_frame(uint8_t *frame, int width, int height) {
  // convert yuv to rgba

  if (use_shader) {
    uint8_t *pu = frame + (width * height);
    uint8_t *pv = pu + (width * height) / 4;

    GLint textureBinding;
    // Save the current texture binding, to avoid messing up SFML's OpenGL
    // states
    glGetIntegerv(GL_TEXTURE_BINDING_2D, &textureBinding);

    // :Y
    sf::Texture::bind(&texY);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width, height, 0, GL_LUMINANCE,
                 GL_UNSIGNED_BYTE, frame);

    // :U
    sf::Texture::bind(&texU);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width / 2, height / 2, 0,
                 GL_LUMINANCE, GL_UNSIGNED_BYTE, pu);

    // :V
    sf::Texture::bind(&texV);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width / 2, height / 2, 0,
                 GL_LUMINANCE, GL_UNSIGNED_BYTE, pv);

    // Restore the previous texture binding
    glBindTexture(GL_TEXTURE_2D, textureBinding);

    // draw frame
    window.draw(sprite, &conv_yuv2rgb_shd);
  } else {
    yu12_to_rgba((uint8_t *)pix, frame, width, height);
    // update texture
    texture.update(pix);
    // draw frame
    window.draw(sprite);
  }

  window.display();

  return 0;
}

void SFMLRender::set_caption(const char *caption) {
  window.setTitle(std::string(caption, 0, 30));
}

void SFMLRender::dispatch_events() {
  // Process events
  sf::Event event;
  while (window.pollEvent(event)) {

    if (event.type == sf::Event::KeyPressed) {
      switch (event.key.code) {
      case sf::Keyboard::Escape:
        render_call_event_callback(EV_QUIT);
        break;
      case sf::Keyboard::Up:
        render_call_event_callback(EV_KEY_UP);
        break;

      case sf::Keyboard::Down:
        render_call_event_callback(EV_KEY_DOWN);
        break;

      case sf::Keyboard::Right:
        render_call_event_callback(EV_KEY_RIGHT);
        break;

      case sf::Keyboard::Left:
        render_call_event_callback(EV_KEY_LEFT);
        break;

      case sf::Keyboard::Space:
        render_call_event_callback(EV_KEY_SPACE);
        break;

      case sf::Keyboard::I:
        render_call_event_callback(EV_KEY_I);
        break;

      case sf::Keyboard::V:
        render_call_event_callback(EV_KEY_V);
        break;

      default:
        break;
      }
    }

    // Close window: exit
    if (event.type == sf::Event::Closed) {
      if (render_verbosity > 0)
        std::cout << "RENDER:(SFML) (event) close\n" << std::endl;
      render_call_event_callback(EV_QUIT);
    }

    if (event.type == sf::Event::Resized) { 
      sf::View view = getLetterboxView( window.getView(), event.size.width, event.size.height );
      window.setView(view);
    }
  }
}

/******************************* C wrapper functions
 * ********************************/
SFMLRender *render = NULL;

/*
 * init sfml render
 * args:
 *    width - render width
 *    height - render height
 *    flags - window flags:
 *              0- none
 *              1- fullscreen
 *              2- maximized
 *   win_w - window width (0 use render width)
 *   win_h - window height (0 use render height)
 *
 * asserts:
 *
 * returns: error code (0 ok)
 */
int init_render_sfml(int width, int height, int flags, int win_w, int win_h) {
  // clean old render
  if (render)
    delete (render);

  render = new SFMLRender(width, height, flags, win_w, win_h);

  if (!render) {
    std::cerr << "RENDER: (SFML) couldn't create render" << std::endl;
    return -1;
  }

  if (!render->has_window()) {
    std::cerr << "RENDER: (SFML) couldn't create render window" << std::endl;
    return -2;
  }

  return 0;
}

/*
 * render a frame
 * args:
 *   frame - pointer to frame data (yuyv format)
 *   width - frame width
 *   height - frame height
 *
 * asserts:
 *   poverlay is not nul
 *   frame is not null
 *
 * returns: error code
 */
int render_sfml_frame(uint8_t *frame, int width, int height) {
  return render->render_frame(frame, width, height);
}

/*
 * set sfml render caption
 * args:
 *   caption - string with render window caption
 *
 * asserts:
 *   none
 *
 * returns: none
 */
void set_render_sfml_caption(const char *caption) {
  render->set_caption(caption);
}

/*
 * dispatch sfml render events
 * args:
 *   none
 *
 * asserts:
 *   none
 *
 * returns: none
 */
void render_sfml_dispatch_events() { render->dispatch_events(); }

/*
 * clean sfml render data
 * args:
 *   none
 *
 * asserts:
 *   none
 *
 * returns: none
 */
void render_sfml_clean() {
  delete (render);
  render = NULL;
}