// ==============================================================
// This file is part of MegaGlest (www.glest.org)
//
// Md5Model.h -- Copyright (c) 2006 David Henry
// changed for use with MegaGlest: Copyright (C) 2011-  by Mark Vejvoda
//
// This code is licensed under the MIT license:
// http://www.opensource.org/licenses/mit-license.php
//
// Open Source Initiative OSI - The MIT License (MIT):Licensing
//
// The MIT License (MIT)
// Copyright (c) <year> <copyright holders>
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.//
//
// Declarations for MD5 Model Classes (object, mesh, animation and
// skeleton).
//
/////////////////////////////////////////////////////////////////////////////
#ifndef __MD5_H__
#define __MD5_H__

#ifdef _WIN32
#define	WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <memory>
#endif // _WIN32

#include <string>
#include <vector>
#include <map>
#include <fstream>
#include <stdexcept>

#if !defined(_WIN32) || defined(__MINGW32__)
#include <tr1/memory>
#endif

#include <GL/glew.h>

#include "Mathlib.h"
#include "md5Texture.h"

namespace Shared { namespace Graphics { namespace md5 {

using std::string;
using std::vector;
using std::map;

#if defined(_WIN32)
using std::tr1::shared_ptr;
#endif

// Forward declarations
class Md5Skeleton;
class Md5Mesh;
class Md5Model;
class Md5Animation;
class Md5Object;
class ShaderProgram;
class ArbVertexProgram;
class ArbFragmentProgram;;

// MD5 Constants
extern const int kMd5Version;

// We can use a specific render path, depending on
// which shader/program we want to use...
enum render_path_e
  {
    R_normal,
    R_ARBfp_diffuse,
    R_ARBfp_diffuse_specular,
    R_ARBfp_ds_parallax,
    R_shader
  };

// Tangent uniform's location
//extern GLint tangentLoc;

// ARB program's tangent location
#define TANGENT_LOC 6

// OpenGL vector types
typedef GLfloat vec2_t[2];
typedef GLfloat vec3_t[3];
typedef GLfloat vec4_t[4];

struct Md5Joint_t
{
  string name;
  int parent;

  Vector3f pos;
  Quaternionf orient;
};


struct Md5Vertex_t
{
  float st[2]; // Texture coordinates

  int startWeight; // Start index weights
  int countWeight; // Number of weights
};


struct Md5Triangle_t
{
  int index[3]; // Vertex indices
};


struct Md5Weight_t
{
  int joint; // Joint index
  float bias;

  Vector3f pos;
  Vector3f norm;
  Vector3f tan;
};


struct BoundingBox_t
{
  Vector3f min;
  Vector3f max;
};


struct OBBox_t
{
  Matrix4x4f world;

  Vector3f center;
  Vector3f extent;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Exception - Exception class for MD5 loader classes.
// This acts like a standard runtime_error exception but
// know which file or mesh has failed to be loaded.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Exception : public std::runtime_error
{
public:
  // Constructors
  Md5Exception (const string &error)
    : std::runtime_error (error) { }
  Md5Exception (const string &error, const string &name)
    : std::runtime_error (error), _which (name) { }
  virtual ~Md5Exception () throw () { }

public:
  // Public interface
  virtual const char *which () const throw () {
    return _which.c_str ();
  }

private:
  // Member variables
  string _which;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Skeleton - Skeleton model data class.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Skeleton
{
public:
  // Constructors/Destructor
  Md5Skeleton () { }
  Md5Skeleton (std::ifstream &file, int numJoints)
    throw (Md5Exception);
  ~Md5Skeleton ();

private:
  // Internal types
  typedef shared_ptr<Md5Joint_t> Md5JointPtr;

public:
  // Public interface
  void draw (const Matrix4x4f &modelView, bool labelJoints);

  void setNumJoints (int numJoints);
  void addJoint (Md5Joint_t *thisJoint);

  Md5Skeleton *clone () const;

  // Accessors
  int numJoints () const { return _joints.size (); }
  Md5Joint_t *joint (int index) const { return _joints[index].get (); }

private:
  // Member variables
  vector<Md5JointPtr> _joints;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Mesh - Mesh data class.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Mesh
{
public:
  // Public internal types
  enum
    {
      kHide,   // Skip mesh
      kNoDraw, // Don't draw but prepare vertices
      kShow,   // Draw mesh
    };

  typedef shared_ptr<Md5Vertex_t> Md5VertexPtr;
  typedef shared_ptr<Md5Triangle_t> Md5TrianglePtr;
  typedef shared_ptr<Md5Weight_t> Md5WeightPtr;

public:
  // Constructor/Destructor
  Md5Mesh (std::ifstream &ifs)
    throw (Md5Exception);
  ~Md5Mesh ();

public:
  // Public interface
  void setupVertexArrays (Md5Skeleton *skel);
  void computeWeightNormals (Md5Skeleton *skel);
  void computeWeightTangents (Md5Skeleton *skel);
  void computeBoundingBox (Md5Skeleton *skel);
  void renderVertexArrays () const;
  void drawNormals () const;

  // Hide/NoDraw/Show state
  void setState (int state) { _renderState = state; }

  // Texture setters
  void setDecalMap (const Texture2D *tex) { _decal = tex; }
  void setSpecularMap (const Texture2D *tex) { _specMap = tex; }
  void setNormalMap (const Texture2D *tex) { _normalMap = tex; }
  void setHeightMap (const Texture2D *tex) { _heightMap = tex; }

  // Accessors
  const string &name () const { return _name; }
  const BoundingBox_t &boundingBox () const { return _boundingBox; }

  // Mesh render state
  bool hiden () const { return (_renderState == kHide);  }
  bool noDraw () const { return (_renderState == kNoDraw); }
  bool show () const { return (_renderState == kShow); }

private:
  // Internal functions
  void preRenderVertexArrays () const;
  void postRenderVertexArrays () const;
  void allocVertexArrays ();
  void setupTexCoordArray ();
  void setupTexture (const Texture2D *tex, GLenum texUnit) const;
  void resetReversedTexture(const Texture2D *tex, GLenum texUnit) const;

private:
  // Member variables
  string _name;
  string _shader;
  int _renderState;

  BoundingBox_t _boundingBox;

  int _numVerts;
  int _numTris;
  int _numWeights;

  // Original mesh data
  vector<Md5VertexPtr> _verts;
  vector<Md5TrianglePtr> _tris;
  vector<Md5WeightPtr> _weights;

  // Final mesh data; vertex arrays for fast rendering
  vector<GLfloat> _vertexArray;
  vector<GLfloat> _normalArray;
  vector<GLfloat> _tangentArray;
  vector<GLfloat> _texCoordArray;
  vector<GLuint> _vertIndices;

  // Textures
  const Texture2D *_decal;
  const Texture2D *_specMap;
  const Texture2D *_normalMap;
  const Texture2D *_heightMap;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Model - MD5 Mesh Model class.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Model
{
public:
  // Constructor/Destructor
  Md5Model (const string &filename)
    throw (Md5Exception);
  ~Md5Model ();

public:
  // Internal type definitions
  typedef shared_ptr<Md5Skeleton> Md5SkeletonPtr;
  typedef shared_ptr<Md5Mesh> Md5MeshPtr;
  typedef shared_ptr<Md5Animation> Md5AnimationPtr;
  typedef map<string, Md5AnimationPtr> AnimMap;

public:
  // Public interface
  void prepare (Md5Skeleton *skel);
  void drawModel () const;
  bool addAnim (const string &filename);

  // Setters
  void setMeshRenderState (const string &name, int state);
  void setMeshDecalMap (const string &name, const Texture2D *tex);
  void setMeshSpecularMap (const string &name, const Texture2D *tex);
  void setMeshNormalMap (const string &name, const Texture2D *tex);
  void setMeshHeightMap (const string &name, const Texture2D *tex);

  // Accessors
  const Md5Animation *anim (const string &name) const;
  int numJoints () const { return _numJoints; }
  const Md5Skeleton *baseSkeleton () const { return _baseSkeleton.get (); }
  const AnimMap &anims () const { return _animList; }
  const BoundingBox_t &bindPoseBoundingBox () const { return _bindPoseBox; }

  static render_path_e renderPath;
  static ShaderProgram *shader;
  static ArbVertexProgram *vp;
  static ArbFragmentProgram *fp;
  static GLint tangentLoc;
  static bool bDrawNormals;

private:
  // Internal functions
  void computeBindPoseBoundingBox ();

  // Check if an animation is valid for this model,
  // i.e. anim's skeleton matches with model's skeleton
  bool validityCheck (Md5Animation *anim) const;

  // Access to a mesh, given its name
  Md5Mesh *getMeshByName (const string &name) const;

private:
  // Member variables
  int _numJoints;
  int _numMeshes;

  Md5SkeletonPtr _baseSkeleton;

  vector<Md5MeshPtr> _meshes;
  AnimMap _animList;

  BoundingBox_t _bindPoseBox;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Animation - MD5 model animation class.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Animation
{
public:
  // Constructor/Destructor
  Md5Animation (const string &filename)
    throw (Md5Exception);
  ~Md5Animation ();

private:
  // Internal type
  struct JointInfo
  {
    string name;
    int parent;

    // NOTE: this structure is stored in
    // little-endian format
    union JointFlags
    {
      short value;

      struct
      {
	bool tx: 1;
	bool ty: 1;
	bool tz: 1;

	bool qx: 1;
	bool qy: 1;
	bool qz: 1;
      };
    } flags;

    int startIndex;
  };

  struct BaseFrameJoint
  {
    Vector3f pos;
    Quaternionf orient;
  };

  typedef shared_ptr<Md5Skeleton> Md5SkeletonPtr;
  typedef shared_ptr<BoundingBox_t> BoundingBoxPtr;

public:
  // Public interface
  void interpolate (int frameA, int frameB,
	    float interp, Md5Skeleton *out) const;

  // Accessors
  int maxFrame () const { return _numFrames - 1; }
  int frameRate () const { return _frameRate; }
  const string &name () const { return _name; }

  Md5Skeleton *frame (int frame) const {
    return _skelframes[frame].get ();
  }

  const BoundingBox_t *frameBounds (int frame) const {
    return _bboxes[frame].get ();
  }

private:
  // Internal functions
  void buildFrameSkeleton (vector<JointInfo> &jointInfos,
			   vector<BaseFrameJoint> &baseFrame,
			   vector<float> &animFrameData);

private:
  // Member variables
  int _numFrames;
  int _frameRate;

  string _name;

  // Store each frame as a skeleton
  vector<Md5SkeletonPtr> _skelframes;

  // Bounding boxes for each frame
  vector<BoundingBoxPtr> _bboxes;
};


/////////////////////////////////////////////////////////////////////////////
//
// class Md5Object - MD5 object class.
//
/////////////////////////////////////////////////////////////////////////////

class Md5Object
{
public:
  // Public internal types/enums
  enum
    {
      kDrawModel = 1,
      kDrawSkeleton = 2,
      kDrawJointLabels = 4,
    };

public:
  // Contructor/Destructor
  Md5Object (Md5Model *model);
  virtual ~Md5Object ();

public:
  // Public interface
  void animate (double dt);
  void computeBoundingBox ();
  void prepare (bool softwareTransformation);
  void render () const;

  // Setters
  void setMd5Model (Md5Model *model);
  void setAnim (const string &name);
  void setModelViewMatrix (const Matrix4x4f &mat) { _modelView = mat; }
  void setRenderFlags (int flags) { _renderFlags = flags; }

  // Accessors
  int renderFlags () const { return _renderFlags; }
  const Md5Model *getModelPtr () const { return _model; }
  const string currAnimName () const { return _currAnimName; }
  const OBBox_t &boundingBox () const { return _bbox; }

protected:
  // Member variables;
  Md5Model *_model;
  Md5Skeleton *_animatedSkeleton;

  Matrix4x4f _modelView;
  bool _softwareTransformation;

  const Md5Animation *_currAnim;
  string _currAnimName;
  unsigned int _currFrame;
  unsigned int _nextFrame;

  double _last_time;
  double _max_time;

  int _renderFlags;

  OBBox_t _bbox;
};

}}} //end namespace

#endif // __MD5_H__