// ======================================================================== //
// Copyright 2009-2014 Intel Corporation                                    //
//                                                                          //
// Licensed under the Apache License, Version 2.0 (the "License");          //
// you may not use this file except in compliance with the License.         //
// You may obtain a copy of the License at                                  //
//                                                                          //
//     http://www.apache.org/licenses/LICENSE-2.0                           //
//                                                                          //
// Unless required by applicable law or agreed to in writing, software      //
// distributed under the License is distributed on an "AS IS" BASIS,        //
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. //
// See the License for the specific language governing permissions and      //
// limitations under the License.                                           //
// ======================================================================== //

#include "tutorial/tutorial.h"
#include "tutorial/obj_loader.h"
#include "tutorial/xml_loader.h"
#include "sys/taskscheduler.h"
#include "image/image.h"

namespace embree 
{
  /* name of the tutorial */
  const char* tutorialName = "tutorial09";

  /* configuration */
  static std::string g_rtcore = "";
  static size_t g_numThreads = 0;
  static std::string g_subdiv_mode = "";

  /* output settings */
  static size_t g_width = 512;
  static size_t g_height = 512;
  static bool g_fullscreen = false;
  static FileName outFilename = "";
  static bool g_interactive = true;

  /* scene */
  OBJScene g_obj_scene;
  static FileName filename = "";

  static std::string getParameterString(Ref<ParseStream> &cin, std::string &term) {

    /*! Parameter name and options. */
    std::string parameter = term + " ";  while (cin->peek() != "" && cin->peek()[0] != '-') parameter += cin->getString();  return(parameter);

  }

  static void initEmbreeState(std::string configuration) {

    /*! Initialize Embree state. */
    init(configuration.c_str());

  }
  
  static void parseCommandLine(Ref<ParseStream> cin, const FileName &path) {

    for (std::string term = cin->getString() ; term != "" ; term = cin->getString()) {

      /*! Command line parameters from a file. */
      if (term == "-c") { FileName file = path + cin->getFileName();  parseCommandLine(new ParseStream(new LineCommentFilter(file, "#")), file.path()); }

      /* load OBJ model*/
      else if (term == "-i") {
        filename = path + cin->getFileName();
      }

      /*! Camera field of view. */
      else if (term == "-fov") g_camera.fov = cin->getFloat();

      /*! Full screen mode. */
      else if (term == "-fullscreen") g_fullscreen = true;

      /* output filename */
	  else if (term == "-o") {
		  g_interactive = false;
		  outFilename = cin->getFileName();
	  }
      
      /*! Embree configuration. */
      else if (term == "-rtcore") g_rtcore = cin->getString();

      /*! Window size. */
      else if (term == "-size") { g_width = cin->getInt();  g_height = cin->getInt(); }

      /*! Thread count. */
      else if (term == "-threads") { g_numThreads = cin->getInt(); }

      /*! Camera view direction. */
      else if (term == "-vd") g_camera.to = g_camera.from + cin->getVec3fa();

      /*! Camera look point. */
      else if (term == "-vi") g_camera.to = cin->getVec3fa();

      /*! Camera position. */
      else if (term == "-vp") g_camera.from = cin->getVec3fa();

      /*! Camera up vector. */
      else if (term == "-vu") g_camera.up = cin->getVec3fa();

      else if (term == "-cache") 
	g_subdiv_mode = ",subdiv_accel=bvh4.subdivpatch1cached";

      else if (term == "-lazy") 
	g_subdiv_mode = ",subdiv_accel=bvh4.grid.lazy";

      else if (term == "-pregenerate") 
	g_subdiv_mode = ",subdiv_accel=bvh4.grid.eager";

      /*! Skip unknown command line parameters. */
      else std::cerr << "Unknown command line parameter: " << getParameterString(cin, term) << std::endl;

    }

  }

  void renderToFile(const FileName& fileName)
  {
    resize(g_width,g_height);
    AffineSpace3fa pixel2world = g_camera.pixel2world(g_width,g_height);

    render(0.0f,
           pixel2world.l.vx,
           pixel2world.l.vy,
           pixel2world.l.vz,
           pixel2world.p);
    
    void* ptr = map();
    Ref<Image> image = new Image4c(g_width, g_height, (Col4c*)ptr);
    storeImage(image, fileName);
    unmap();
    cleanup();
  }

  void main(int argc, char **argv) 
  {
    std::cout << " === Possible cmd line options: -lazy, -pregenerate, -cache === " << std::endl;

    /* set default camera */
    g_camera.from = Vec3fa(1.5f,1.5f,-1.5f);
    g_camera.to   = Vec3fa(0.0f,0.0f,0.0f);

    /*! Parse command line options. */  
    parseCommandLine(new ParseStream(new CommandLineStream(argc, argv)), FileName());

    /*! Set the thread count in the Embree configuration string. */
    if (g_numThreads) g_rtcore += ",threads=" + std::stringOf(g_numThreads);
    g_rtcore += g_subdiv_mode;

    /*! Initialize the task scheduler. */
#if !defined(RTCORE_EXPORT_ALL_SYMBOLS)
    TaskScheduler::create(g_numThreads);
#endif

    /*! Initialize Embree state. */
    init(g_rtcore.c_str());

    /* render to disk */
    if (outFilename.str() != "")
      renderToFile(outFilename);
    
    /* interactive mode */
    if (g_interactive) {
      initWindowState(argc,argv,tutorialName, g_width, g_height, g_fullscreen);
      enterWindowRunLoop();
    }
  }
}

int main(int argc, char** argv) 
{
  /*! Tutorial entry point. */
  try { embree::main(argc, argv);  return(0); }

  /*! Known exception. */
  catch (const std::exception& e) { std::cout << "Error: " << e.what() << std::endl;  return(1); }

  /*! Unknown exception. */
  catch (...) { std::cout << "Error: unknown exception caught." << std::endl;  return(1); }

}