/*!
  \file model.h
  \brief Contains the Model Class that handles 3D-Models
*/

#ifndef _MODEL_H
#define _MODEL_H

#include "abstract_model.h"

#include "material.h"
#include "glincl.h"
#include "array.h"


// FORWARD DECLARATION //
template<class T> class tArray;
template<class T> class tList;


//! an enumerator fot the different Model Types.
/**
   MODEL_DISPLAY_LIST means, that a DisplayList will be built out of the model. This model will be STATIC, meaning it cannot be changed after initialisation.
   MODEL_VERTEX_ARRAY means, that a VertexArray will be built out of the model. This moel will be DYNAMIX, meaning that one can change the properties from outside of the model.
 * @todo implement this stuff
*/
typedef enum MODEL_TYPE {
  MODEL_DISPLAY_LIST,
  MODEL_VERTEX_ARRAY
};


// definition of different modes for setting up Faces
#define VERTEX 0       //!< If Faces are created WITH Vertex-Coordinate
#define NORMAL 1       //!< If Faces are created WITH Normals (otherwise autocalculate)
#define TEXCOORD 2     //!< If Faces are created WITH TextureCoordinate

//! an enumerator for VERTEX_FORMAT
typedef enum VERTEX_FORMAT {
  VERTEX_ONLY = VERTEX,
  VERTEX_NORMAL = NORMAL,
  VERTEX_TEXCOORD = TEXCOORD,
  VERTEX_TEXCOORD_NORMAL = NORMAL | TEXCOORD
};

////////////////////
/// SUB-ELEMENTS ///
////////////////////
//! This is the placeholder of one Vertex beloning to a Face.
class ModelFaceElement
{
 public:
  ModelFaceElement();
  ~ModelFaceElement();

  int                 vertexNumber;         //!< The number of the Vertex out of the Array* vertices, this vertex points to.
  int                 normalNumber;         //!< The number of the Normal out of the Array* normals, this vertex points to.
  int                 texCoordNumber;       //!< The number of the textureCoordinate out of the Array* vTexture, this vertex points to.

  ModelFaceElement*   next;                 //!< Point to the next FaceElement in this List.
};

//! This is the placeholder of a Face belonging to a Group of Faces.
class ModelFace
{
 public:
  ModelFace();
  ~ModelFace();

  unsigned int        vertexCount;     //!< The Count of vertices this Face has.
  ModelFaceElement*   firstElem;       //!< Points to the first Vertex (FaceElement) of this Face.
  Material*           material;        //!< The Material to use.

  ModelFace*          next;            //!< Pointer to the next Face.
};

//! Group to handle multiple Models per obj-file.
class ModelGroup
{
 public:
  ModelGroup();
  ~ModelGroup();

  void cleanup();

  char*        name;           //!< the Name of the Group. this is an identifier, that can be accessed via the draw (char* name) function.
  GLubyte*     indices;        //!< The indices of the Groups. Needed for vertex-arrays
  GLuint       listNumber;     //!< The number of the GL-List this Group gets.
  ModelFace*   firstFace;      //!< The first Face in this group.
  ModelFace*   currentFace;    //!< The current Face in this Group (the one we are currently working with.)
  int          faceMode;       //!< The Mode the Face is in: initially -1, 0 for FaceList opened, 1 for Material,  3 for triangle, 4 for Quad, 5+ for Poly @todo ENUM...
  int          faceCount;      //!< The Number of Faces this Group holds.

  ModelGroup*  next;           //!< Pointer to the next Group.
};

struct ModelMaterial
{
  Material* material;
  bool external;
};

/////////////
/// MODEL ///
/////////////
//! Class that handles 3D-Models. it can also read them in and display them.
class Model : public AbstractModel
{
 public:
  Model(const char* modelName = NULL, MODEL_TYPE type = MODEL_DISPLAY_LIST);
  virtual ~Model();

  void draw() const;
  void draw(int groupNumber) const;
  void draw(char* groupName) const;

  /** @returns Count of the Models (Groups) in this File */
  inline int getGroupCount() const { return this->groupCount; };

  /** @returns a Pointer to the Vertex-Array, if it was deleted it returns NULL */
  inline const GLfloat* getVertexArray() const { return this->vertices->getArray(); };
  /** @returns the VertexCount of this Model */
  inline unsigned int getVertexCount() const { return this->vertexCount; };

  /** @returns a Pointer to the Normals-Array, if it was deleted it returns NULL */
  inline const GLfloat* getNormalsArray() const { return this->normals->getArray(); };
  /** @returns the NormalsCount of this Model */
  inline unsigned int getNormalsCount() const { return this->normalCount; };

  /** @returns a Pointer to the TexCoord-Array, if it was deleted it returns NULL */
  inline const GLfloat* getTexCoordArray() const { return this->vTexture->getArray(); };
  /** @returns the TexCoord-Count of this Model */
  inline unsigned int getTexCoordCount() const { return this->texCoordCount; };

  /** @returns the Count of Faces of this Model */
  inline unsigned int getFaceCount() const { return this->faceCount; };


  Material* addMaterial(Material* material);
  Material* addMaterial(const char* materialName);

  bool addGroup(const char* groupString);
  bool addVertex(const char* vertexString);
  bool addVertex(float x, float y, float z);
  bool addFace(const char* faceString);
  bool addFace(int faceElemCount, VERTEX_FORMAT type, ...);
  bool addVertexNormal(const char* normalString);
  bool addVertexNormal(float x, float y, float z);
  bool addVertexTexture(const char* vTextureString);
  bool addVertexTexture(float u, float v);
  bool setMaterial(const char* mtlString);
  bool setMaterial(Material* mtl);
  void finalize();


 protected:
  void cubeModel();

  Material* findMaterialByName(const char* materialName);


 protected:
  float            scaleFactor;     //!< The Factor with which the Model should be scaled. @todo maybe one wants to scale the Model after Initialisation

 private:
  bool buildVertexNormals();

  bool importToDisplayList();
  bool buildTriangleList();
  bool addGLElement(ModelFaceElement* elem);

  bool importToVertexArray();

  bool deleteArrays();
  bool cleanup();

 private:
  MODEL_TYPE             type;            //!< A type for the Model
  bool                   finalized;       //!< Sets the Object to be finalized.

  unsigned int           vertexCount;     //!< A modelwide Counter for vertices.
  unsigned int           normalCount;     //!< A modelwide Counter for the normals.
  unsigned int           texCoordCount;   //!< A modelwide Counter for the texCoord.
  unsigned int           faceCount;       //!< A modelwide Counter for the faces
  unsigned int           triangleCount;   //!< Number of triangles >= faceCount
  tArray<GLfloat>*       vertices;        //!< The Array that handles the Vertices.
  tArray<GLfloat>*       normals;         //!< The Array that handles the Normals.
  tArray<GLfloat>*       vTexture;        //!< The Array that handles the VertexTextureCoordinates.
  sTriangleExt*          triangles;       //!< The Array of triangles in the abstract_model.h style

  ModelGroup*            firstGroup;      //!< The first of all groups.
  ModelGroup*            currentGroup;    //!< The currentGroup. this is the one we will work with.
  int                    groupCount;      //!< The Count of Groups.

  tList<ModelMaterial>*  materialList;    //!< A list for all the Materials in this Model
};

#endif