/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   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, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: bottac@ee.ethz.ch

   review: patrick boenzli, patrick@orxonox.ethz.ch
*/

#include "height_map.h"
#include "model.h"
#include "texture.h"
#include "vector.h"
#include "material.h"
#include "p_node.h"
#include "state.h"
#include "util/loading/resource_manager.h"
#include "debug.h"

// INCLUDING SDL_Image
#ifdef HAVE_SDL_IMAGE_H
#include <SDL_image.h>
#else
#include <SDL/SDL_image.h>
#endif


/**
 * default constructor
 *  @param xOffset
 */
Tile::Tile(int xOffset, int yOffset, int i2, int j2, HeightMap* heightMapReference )
{
  PRINTF(0)("Tile Constructor\n");

  this->highResModel = new VertexArrayModel();
  this->lowResModel  = new VertexArrayModel();

  this->heightMapReference = heightMapReference;

  // create high res model
  this->load(xOffset, yOffset, i2, j2, this->highResModel, 4);
  // create low res model
  this->load(xOffset, yOffset, i2, j2, this->lowResModel, 8);
}


Tile::~Tile()
{
  if( highResModel)
    delete highResModel;
  if( lowResModel)
    delete lowResModel;
}


/**
 * this darws the tile in diefferent resolutions
 */
void Tile::draw()
{
  // draw the tile depending on the distance from the camera with different LOD (level of details)
  float cameraDistance = fabs((State::getCameraNode()->getAbsCoor() - Vector(this->x, heightMapReference->offsetY , this->z) ).len());

  if (cameraDistance < HM_LOD_HIGH_RES )
  {
    this->drawHighRes();
  }
  else if( cameraDistance < HM_LOD_LOW_RES)
  {
    this->drawLowRes();
  }
}


/**
 * loads a tile
 */
void Tile::load(int xOffset, int yOffset, int i2, int j2, VertexArrayModel* model, int sampleRate)
{

// #define heightMap this->heightMapReference->heightMap
#define colors   this->heightMapReference->colors
#define scaleX this->heightMapReference->scaleX
#define scaleY this->heightMapReference->scaleY
#define scaleZ this->heightMapReference->scaleZ
#define shiftX this->heightMapReference->shiftX
#define shiftY this->heightMapReference->shiftY
#define shiftZ this->heightMapReference->shiftZ
#define normalVectorField this->heightMapReference->normalVectorField


  //FIXME: OLD implementation
  this->x = this->heightMapReference->offsetX + ( this->heightMapReference->heightMap->h - ((xOffset + i2) / 2)) * scaleX;
  this->z = this->heightMapReference->offsetZ + ((yOffset + j2 ) / 2 ) * scaleZ;
  //NEW:
  this->setAbsCoor(this->heightMapReference->offsetX + ( this->heightMapReference->heightMap->h - ((xOffset + i2) / 2)) * scaleX,
                   0,
                   this->heightMapReference->offsetZ + ((yOffset + j2 ) / 2 ) * scaleZ);


  float height = 0;

  float r = 0.0;
  float g = 0.0;
  float b = 0.0;


  //if( this->heightMapReference->heightMap != NULL && this->heightMapReference->heightMap->format->BitsPerPixel == 8 )

  SDL_LockSurface(this->heightMapReference->heightMap);
  SDL_LockSurface(this->heightMapReference->colorMap);

  for( int i = xOffset ; i <= i2  ; i +=sampleRate)
  {
    int w = 0;

    // adjust the colors acoring to the color map
    if( this->heightMapReference->hasColourMap)
    {
      r = colors[3 * w + 2 + 3 * i * this->heightMapReference->heightMap->w];
      g = colors[3 * w + 1 + 3 * i * this->heightMapReference->heightMap->w];
      b = colors[3 * w + 0 + 3 * i * this->heightMapReference->heightMap->w];
    }

    w = yOffset;

//    PRINTF(0)("Values: i = %i, w = %i\n", i, w);

    // add a vertex to the list
    model->addVertex(scaleX * (this->heightMapReference->heightMap->h - i) + shiftX, shiftY, scaleZ * w + shiftZ); // Top Right
    model->addNormal(normalVectorField[i % this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].y,
                     normalVectorField[i % this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].z,
                     normalVectorField[i % this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)(yOffset-sampleRate) /(HM_TEX_RATE), (float)(i %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);


    for(int j = yOffset; j <= j2; j += sampleRate)
    {
      // adjust the colors acording to the color map
      if( this->heightMapReference->hasColourMap)
      {
        r = colors[3 * j + 2 + 3 * i * this->heightMapReference->heightMap->w];
        g = colors[3 * j + 1 + 3 * i * this->heightMapReference->heightMap->w];
        b = colors[3 * j + 0 + 3 * i * this->heightMapReference->heightMap->w];
      }
      height =  (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * (this->heightMapReference->heightMap->w)];
      height += (float)(unsigned char)this->heightMapReference->heights[j + 1 + sampleRate + (i + 1) *
                                                                        this->heightMapReference->heightMap->w];
      height += (float)(unsigned char)this->heightMapReference->heights[j - 1 + sampleRate + (i + 1) *
                                                                        this->heightMapReference->heightMap->w];
      height += (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + (i + 2) *
                                                                        this->heightMapReference->heightMap->w];
      height += (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * (this->heightMapReference->heightMap->w)];
      height /= 5.0;

      model->addVertex(scaleX * (this->heightMapReference->heightMap->h -i) + shiftX ,
                       ((double)(height)*scaleY) + shiftY ,
                       scaleZ*(j) + shiftZ); // Top Right
      model->addNormal(normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].y,
                       normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].z,
                       normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].x);
      model->addTexCoor((float)(j) /(HM_TEX_RATE), (float)(i %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
      model->addColor(r/255.0f, g/255.0f, b/255.0f);
      //PRINTF(0)("TexCoord:  %f %f \n",(float)j / 100.0, (float)(i %this->heightMapReference->h)/100.0);

      w = j;
    }
    model->addVertex(scaleX*(this->heightMapReference->heightMap->h -i)+ shiftX,shiftY,scaleZ*(w)+ shiftZ); // Top Right
    model->addNormal(normalVectorField[i % this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].y,
                     normalVectorField[i % this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].z,
                     normalVectorField[i% this->heightMapReference->heightMap->h][w % this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)(j2+sampleRate) /(HM_TEX_RATE), (float)(i %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);
  }

  SDL_UnlockSurface(this->heightMapReference->heightMap);
  int cnt = 0;

  for( int i = xOffset; i < i2; i +=sampleRate)
  {
    for( int j = yOffset-sampleRate; j < j2  + 2 * sampleRate; j += sampleRate)
    {
      model->addIndice(cnt);
      model->addIndice(cnt  + (j2 -yOffset + 3* sampleRate  )/ sampleRate );
      cnt++;
    }
    model->newStripe();
  }
  cnt += (j2 -yOffset + 3* sampleRate)/ sampleRate;

  for( int j = yOffset; j <= j2; j += sampleRate)
  {
    int i = xOffset;

    // To be fixed
    if(this->heightMapReference->hasColourMap)
    {
      r = (float)colors[3 * j + 2 + 3 * i * this->heightMapReference->heightMap->w];
      g = (float)colors[3 * j + 1 + 3 * i * this->heightMapReference->heightMap->w];
      b = (float)colors[3 * j + 0 + 3 * i * this->heightMapReference->heightMap->w];
    }

    model->addVertex(scaleX*(this->heightMapReference->heightMap->h -i) + shiftX ,
                     shiftY ,
                     scaleZ*(j) + shiftZ); // Top Right
    model->addNormal(normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].y,
                     normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].z,
                     normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)j /(HM_TEX_RATE), (float)((i - sampleRate) %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);
  }


  for(int j = yOffset  ; j <= j2    ;  j += sampleRate)
  {
    int i = xOffset;
    height =  (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j + 1 + sampleRate + (i + 1) *
                                                                      this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j - 1 + sampleRate + (i + 1) *
                                                                      this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + (i + 2) *
                                                                      this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * this->heightMapReference->heightMap->w];
    height=height/5.0;

    model->addVertex(scaleX*(this->heightMapReference->heightMap->h -i) + shiftX ,
                     ((double)(height)*scaleY) +shiftY ,
                     scaleZ*(j) + shiftZ); // Top Right
    model->addNormal(normalVectorField[i % this->heightMapReference->heightMap->h][j % this->heightMapReference->heightMap->w].y,
                     normalVectorField[i % this->heightMapReference->heightMap->h][j% this->heightMapReference->heightMap->w].z,
                     normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)j /(HM_TEX_RATE), (float)(i %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);
  }


  for(int j = yOffset; j <= j2; j += sampleRate)
  {
    int i = i2;
    // To be fixed
    if( this->heightMapReference->hasColourMap)
    {
      r = (float)colors[3 * j + 2 + 3 * i * this->heightMapReference->heightMap->w];
      g = (float)colors[3 * j + 1 + 3 * i * this->heightMapReference->heightMap->w];
      b = (float)colors[3 * j + 0 + 3 * i * this->heightMapReference->heightMap->w];
    }

    model->addVertex(scaleX*(this->heightMapReference->heightMap->h -i) + shiftX ,
                     shiftY ,
                     scaleZ*(j) + shiftZ); // Top Right
    model->addNormal(normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].y,
                     normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].z,
                     normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)j /(HM_TEX_RATE), (float)((i+ sampleRate) %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);
  }


  for(int j = yOffset; j <= j2; j += sampleRate)
  {
    int i = i2;
    height =  (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j + 1 + sampleRate + (i + 1)
                                                                      * this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j - 1 + sampleRate + (i + 1) *
                                                                      this->heightMapReference->heightMap->w];
    height += (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + (i + 2) *
                                                                      this->heightMapReference->heightMap->w];
    height +=  (float)(unsigned char)this->heightMapReference->heights[j + sampleRate + i * this->heightMapReference->heightMap->w];
    height /= 5.0;
    model->addVertex(scaleX*(this->heightMapReference->heightMap->h -i) + shiftX ,
                     ((double)(height)*scaleY) +shiftY ,
                     scaleZ*(j) + shiftZ); // Top Right
    model->addNormal(normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].y,
                     normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].z,
                     normalVectorField[i%this->heightMapReference->heightMap->h][j%this->heightMapReference->heightMap->w].x);
    model->addTexCoor((float)j /(HM_TEX_RATE), (float)(i %this->heightMapReference->heightMap->h)/(HM_TEX_RATE));
    model->addColor(r/255.0f, g/255.0f, b/255.0f);
  }

  // link Boarder Stripe
  for(int j = yOffset - sampleRate; j < j2; j += sampleRate)
  {
    model->addIndice(cnt);
    model->addIndice(cnt + (j2 - yOffset + sampleRate) / sampleRate );
    cnt++;
  }
  cnt++;


  model->newStripe();


  cnt += (j2-yOffset)/ sampleRate;
  // link 2nd BoarderStripe
  for(int j = yOffset-sampleRate; j < j2;  j += sampleRate)
  {
    model->addIndice(cnt);
    model->addIndice(cnt + (j2 - yOffset + sampleRate) / sampleRate);
    cnt++;
  }

  SDL_UnlockSurface(this->heightMapReference->colorMap);

  model->finalize();

// #undef heightMap
        #undef colors
        #undef scaleX
        #undef scaleY
        #undef scaleZ
        #undef shiftX
        #undef shiftY
        #undef shiftZ
        #undef normalVectorField
}




/**
 * constructor
 *  @param heightMapName file name of the height map
 */
HeightMap::HeightMap(const std::string& heightMapName)
    : VertexArrayModel()
{
  this->init(heightMapName);

  this->colorMap = NULL;
}


/**
 * constructor
 *  @param heightMapName file name of the height map
 *  @param colorMapName file name of the color map
 */
HeightMap::HeightMap(const std::string& heightMapName, const std::string& colorMapName)
    : VertexArrayModel()
{
  this->init(heightMapName);

  this->colorMap = IMG_Load(colorMapName.c_str());
  if( this->colorMap != NULL)
  {
    PRINTF(0)("loading Image %s\n", colorMapName.c_str());
    PRINTF(0)("width : %i\n", this->colorMap->w);
    PRINTF(0)("height : %i\n", this->colorMap->h);
    PRINTF(0)("%i Byte(s) per Pixel \n", this->colorMap->format->BytesPerPixel);
    PRINTF(0)("Rshift : %i\n", this->colorMap->format->Rshift);
    PRINTF(0)("Bshift: %i\n", this->colorMap->format->Bshift);
    PRINTF(0)("Gshift: %i\n", this->colorMap->format->Gshift);
    PRINTF(0)("Rmask: %i\n", this->colorMap->format->Rmask);
    PRINTF(0)("Gmask: %i\n", this->colorMap->format->Gmask);

    this->colors = (unsigned char *) colorMap->pixels;
    this->hasColourMap = true;
  }
  else
  {
    PRINTF(0)("oops! couldn't load colorMap for some reason.\n");
    this->hasColourMap = false;
  }
}


/**
 * deconstructor
 */
HeightMap::~HeightMap()
{
  if( heightMap)
    delete heightMap;
  if( colorMap)
    delete colorMap;

  if( this->tiles)
  {
    for( int i = 0; i < heightMap->h / HM_TILE_SIZE; i++) {
      for( int j = 0; j < heightMap->w / HM_TILE_SIZE; j++) {
        delete tiles [i][j];
      }
    }

    for( int i = 0; i < heightMap->h / HM_TILE_SIZE; i++)
      delete[] tiles[i];
    delete[] tiles;
  }

  if( this->normalVectorField)
  {
    for(int i = 0; i < heightMap->h; i++)
      delete[] normalVectorField[i];
    delete[] normalVectorField;
  }
}


/**
 * this is the init function with stuff shared between all constructors
 */
void HeightMap::init(const std::string& heightMapName)
{
  this->setClassID(CL_HEIGHT_MAP, "HeightMap");

  this->shiftX = 0;
  this->shiftY = 0;
  this->shiftZ = 0;

  heightMap =  IMG_Load(heightMapName.c_str());
  if( heightMap != NULL)
  {
    /*
    WHAT about following checks:
    - image size (rectangular?)
    - image file type (bw?)
    */
    PRINTF(1)("loading Image %s\n", heightMapName.c_str());
    PRINTF(1)("width : %i\n", heightMap->w);
    PRINTF(1)("height : %i\n", heightMap->h);
    PRINTF(1)("%i Byte(s) per Pixel \n", heightMap->format->BytesPerPixel);
    PRINTF(1)("Rshift : %i\n", heightMap->format->Rshift);
    PRINTF(1)("Bshift: %i\n", heightMap->format->Bshift);
    PRINTF(1)("Gshift: %i\n", heightMap->format->Gshift);
    PRINTF(1)("Rmask: %i\n", heightMap->format->Rmask);
    PRINTF(1)("Gmask: %i\n", heightMap->format->Gmask);
  }
  else
    PRINTF(1)("oops! couldn't load %s for some reason.\n", heightMapName.c_str());

  this->generateNormalVectorField();

  this->heights = (unsigned char*)heightMap->pixels;
}


/**
 * this function loads the heightmap by creatin tiles
 */
void HeightMap::load()
{
  // create a dynamicly sized 2D-array for tiles
  this->tiles =  new Tile**[this->heightMap->h / HM_TILE_SIZE];

  for( int i = 0;i < heightMap->h / HM_TILE_SIZE; i++)
    this->tiles [i]= new Tile*[this->heightMap->w / HM_TILE_SIZE];

  // setup arrays
  for( int i = 0; i < this->heightMap->h / HM_TILE_SIZE; i++)  {
    for( int j = 0; j < this->heightMap->w / HM_TILE_SIZE; j++) {
      this->tiles[i][j] = new Tile( i * HM_TILE_SIZE ,  j * HM_TILE_SIZE , (i+1) * HM_TILE_SIZE, (j+1) * HM_TILE_SIZE , this);
    }
  }
}


/**
 * this function draws the height map
 */
void HeightMap::draw() const
{
  Vector v = State::getCameraNode()->getAbsCoor();

  int i_max = (heightMap->h )/ HM_TILE_SIZE;
  int j_max= (heightMap->w  ) / HM_TILE_SIZE;



  /* process the draw command to the tiles, FIXME: think of something more efficient*/
  for( int i = 0; i < i_max; i++)  {
    for( int j = 0; j < j_max; j++)  {
      tiles[i][j]->draw();
    }
  }
}


/**
 * this function generates the normal vector field
 */
void HeightMap::generateNormalVectorField()
{
  int delta = 1;
  heights  = (unsigned char*) heightMap->pixels;

  //Create a Dynamicly sized 2D-Array to store our normals
  normalVectorField =  new Vector* [heightMap->h];
  for(int i=0;i<heightMap->h;i++)
    normalVectorField [i]= new (Vector [heightMap->w]);

  // Initialize
  for(int i=0; i< heightMap->h; i++)
  {
    for(int j = 0; j> heightMap->w; j++)
    {
      Vector v = Vector(0.0, 1.0, 0.0);
      normalVectorField[i][j] = v;
    }
  }

  // !!! Does not yet calculate the normals of some border points!!!!!

  if(heightMap != NULL && heightMap->format->BitsPerPixel == 8 )
  {
    SDL_LockSurface(heightMap);
    for(int i = 0 ; i < heightMap->h - 1  ; i ++)
    {
      for(int j = 0; j < heightMap->w  - 1  ;  j ++)
      {


        delta = (int)heights[j + (i+1)*(heightMap->w )] -  (int) heights[j + i*(heightMap->w )];
        Vector a =  Vector(-scaleX,(float)delta*scaleY  ,0.0f);

        delta = (int)heights[j+1 + i*(heightMap->w )] - (int)heights[j + i*(heightMap->w )];
        Vector b =  Vector(0.0f,(float) delta*scaleY ,scaleZ);


        normalVectorField[i][j] = b.cross(a);
        normalVectorField[i][j].normalize();

      }
    }
    SDL_UnlockSurface(heightMap);

  }
}


/**
 * scales the height map about a vector
 *  @param v scaling vector
 */
void HeightMap::scale(Vector v)
{
  scaleX = v.x;
  scaleY = v.y;
  scaleZ = v.z;
  generateNormalVectorField();
}


/**
 * sets the absolute coordinates of the height map
 *  @param v the moving vector
 */
void HeightMap::setAbsCoor(Vector v)
{
  offsetX = v.x;
  offsetY = v.y;
  offsetZ = v.z;
}


/**
 * returns the height at a given 2D coordinate
 *  @param x x coordinate of the height map (world space)
 *  @param y y coordinate of the height map (world space)
 *  @return the height (z)
 */
float HeightMap::getHeight(float x, float y)
{
  x -= offsetX;
  y -= offsetZ;

  int xInt = (int)( x / scaleX);
  x -= (float)((int)x);
  xInt = heightMap->h - xInt;
  int yInt = (int)( y / scaleZ);
  y -= (float) ((int) y); /*yInt = heightMap->w - yInt;*/

  //PRINTF(0)("xInt: %i, yInt: %i, x: %f, y: %f\n", xInt, yInt, x, y);

  if(xInt <= 0 || xInt >= heightMap->h || yInt <= 0 || yInt >= heightMap->w  )
    return 0;
  if( y >= 0.5*x)
  {
    // Check for ...
  }

  float height = heights[yInt + (xInt)*heightMap->w]*scaleY;

  float a = normalVectorField[(xInt)][yInt].x;
  float b = normalVectorField [(xInt)][yInt].z;
  float c = normalVectorField [(xInt)][yInt].y;

//  PRINTF(0)("a: %f \n" ,a);
//  PRINTF(0)("b: %f \n" ,b);
//  PRINTF(0)("c: %f \n" ,c);


  height -= ( (a/c)*(x) + (b/c)*(y));

  // PRINTF(0)("height: %f \n" ,height );
  return (height + offsetZ);

}