/*  Starshatter: The Open Source Project
    Copyright (c) 2021-2022, Starshatter: The Open Source Project Contributors
    Copyright (c) 2011-2012, Starshatter OpenSource Distribution Contributors
    Copyright (c) 1997-2006, Destroyer Studios LLC.

    AUTHOR:       John DiCamillo


    OVERVIEW
    ========
    File loader for 3DStudio MAX 3DS format models
*/

#include "StdAfx.h"
#include "Magic.h"
#include "MagicDoc.h"
#include "ModelFile3DS.h"

#include "Bitmap.h"
#include "Polygon.h"
#include "Text.h"
#include "List.h"
#include "ArrayList.h"

// +--------------------------------------------------------------------+

struct Chunk
{
   WORD  id;
   DWORD len;
   BYTE* start;

   List<Chunk> chunks;
};

// +--------------------------------------------------------------------+

struct Vec2
{
   float u,v;
};

struct Triangle
{
   WORD a,b,c;
};

struct Triangle2
{
   Vec3     vloc[3];
   Vec3     vnrm[3];
   Vec2     vtex[3];
   Vec3     fnrm;
   DWORD    mtl_id;
};

struct TextureMap
{
   char     fname[256];
   float    strength;
   float    u_scale;
   float    v_scale;
   float    u_offset;
   float    v_offset;
   float    angle;
};

// +--------------------------------------------------------------------+

class Object3DS
{
public:
   Object3DS();
   virtual ~Object3DS();

   virtual const char*  GetName();
   virtual bool         IsObject(const char* name);

protected:
    Text    name;
};

// +--------------------------------------------------------------------+

class Material3DS : public Object3DS
{
public:
   Material3DS();
   virtual ~Material3DS();

   DWORD       GetID();
   TextureMap& GetTextureMap1();
   TextureMap& GetTextureMap2();
   TextureMap& GetOpacityMap();
   TextureMap& GetSpecularMap();
   TextureMap& GetBumpMap();
   TextureMap& GetReflectionMap();
   ColorValue  GetAmbientColor();
   ColorValue  GetDiffuseColor();
   ColorValue  GetSpecularColor();
   float       GetShininess();
   float       GetTransparency();
   DWORD       GetShadingType();

   // this methods should not be used by the "user", they're used internally to fill the class
   // with valid data when reading from file. If you're about to add an importer for another format you'LL
   // have to use these methods

   void        SetID(DWORD value);
   void        SetAmbientColor(const ColorValue &color);
   void        SetDiffuseColor(const ColorValue &color);
   void        SetSpecularColor(const ColorValue &color);
   void        SetShininess(float value);
   void        SetTransparency(float value);
   void        SetShadingType(DWORD shading);

protected:
   int         id;
   TextureMap  texMap1;
   TextureMap  texMap2;
   TextureMap  opacMap;
   TextureMap  refTextureMap;
   TextureMap  bumpMap;
   TextureMap  specMap;
   ColorValue  ambient;
   ColorValue  diffuse;
   ColorValue  specular;
   float       shininess;
   float       transparency;
   DWORD       shading;
};

// +--------------------------------------------------------------------+

class Mesh3DS : public Object3DS
{
public:
    Mesh3DS();
    virtual ~Mesh3DS();

    void    Clear();

    DWORD   GetVertexCount();
    void    SetVertexArraySize(DWORD value);
    DWORD   GetTriangleCount();
    void    SetTriangleArraySize(DWORD value);

    const Vec3&   GetVertex(DWORD index);
    const Vec3&   GetNormal(DWORD index);
    const Vec2&   GetUV(DWORD index);
    const Vec3&   GetTangent(DWORD index);
    const Vec3&   GetBinormal(DWORD index);

    void          SetVertex(const Vec3 &vec, DWORD index);
    void          SetNormal(const Vec3 &vec, DWORD index);
    void          SetUV(const Vec2 &vec, DWORD index);
    void          SetTangent(const Vec3 &vec, DWORD index);
    void          SetBinormal(const Vec3 &vec, DWORD index);

    const Triangle&  GetTriangle(DWORD index);
    Triangle2        GetTriangle2(DWORD index);

    Matrix&       GetMatrix();
    void          SetMatrix(Matrix& m);
    void          Optimize(int level);

    DWORD         GetMaterial(DWORD index);
    DWORD         AddMaterial(DWORD id);
    DWORD         GetMaterialCount();

protected:
    // the vertices, normals, etc.
    List<Vec3>       vertices;
    List<Vec3>       normals;
    List<Vec3>       binormals;
    List<Vec3>       tangents;
    List<Vec2>       uv;

    // triangles
    List<Triangle>   triangles;

    // the transformation matrix.
    Matrix           matrix;

    // the material ID array
    ArrayList        materials;

    void CalcNormals(bool useSmoothingGroups);
    void CalcTextureSpace();

    void TransformVertices();
};


// +--------------------------------------------------------------------+
// +--------------------------------------------------------------------+
// +--------------------------------------------------------------------+

ModelFile3DS::ModelFile3DS(const char* fname)
   : ModelFile(fname)
{
}

ModelFile3DS::~ModelFile3DS()
{
}

// +--------------------------------------------------------------------+

static int mcomp(const void* a, const void* b)
{
   Poly* pa = (Poly*) a;
   Poly* pb = (Poly*) b;

   if (pa->sortval == pb->sortval)
      return 0;

   if (pa->sortval < pb->sortval)
      return 1;

   return -1;
}

bool
ModelFile3DS::Load(Model* m, double scale)
{
   if (m && scale > 0 && strlen(filename) > 0) {
      ModelFile::Load(m, scale);

      FILE* fp = fopen(filename, "rb");
      fclose(fp);

      m->Normalize();
      return true;
   }

   return false;
}

// +--------------------------------------------------------------------+

bool
ModelFile3DS::Save(Model* m)
{
   if (m) {
      ModelFile::Save(m);

      FILE* f = fopen(filename, "w");
      if (!f) {
         ::MessageBox(0, "Export Failed: Magic could not open the file for writing", "ERROR", MB_OK);
         return false;
      }

      fclose(f);

      return true;
   }

   return false;
}

// +--------------------------------------------------------------------+