/* 
A* -------------------------------------------------------------------
B* This file contains source code for the PyMOL computer program
C* copyright 1998-2005 by Warren Lyford Delano of DeLano Scientific. 
D* -------------------------------------------------------------------
E* It is unlawful to modify or remove this copyright notice.
F* -------------------------------------------------------------------
G* Please see the accompanying LICENSE file for further information. 
H* -------------------------------------------------------------------
I* Additional authors of this source file include:
-* 
-* 
-*
Z* -------------------------------------------------------------------
*/

#include "MemoryDebug.h"
#include "Base.h"

#include "TypeFace.h"

#ifdef _PYMOL_FREETYPE

#include <ft2build.h>
#include FT_FREETYPE_H

struct _CType {
  FT_Library library;
};

struct _CTypeFace {
  PyMOLGlobals *G;
  FT_Face Face;
  float LastSize;
};

int TypeFaceCharacterNew(CTypeFace * I, CharFngrprnt * fprnt, float size)
{
  FT_GlyphSlot slot = I->Face->glyph;   /* a small shortcut */
  if(I->LastSize != size) {
    I->LastSize = size;
    FT_Set_Char_Size(I->Face,   /* handle to face object */
                     0,         /* char_width in 1/64th of points */
                     (int) (size * 64), /* char_height in 1/64th of points */
                     72,        /* horizontal device resolution */
                     72);       /* vertical device resolution */

  }
  if(!FT_Load_Char(I->Face, fprnt->u.i.ch, FT_LOAD_RENDER))
    return CharacterNewFromBytemap(I->G,
                                   slot->bitmap.width,
                                   slot->bitmap.rows,
                                   -slot->bitmap.pitch,
                                   slot->bitmap.buffer +
                                   ((slot->bitmap.rows - 1) * slot->bitmap.pitch),
                                   (float) -slot->bitmap_left,
                                   (float) slot->bitmap.rows - slot->bitmap_top,
                                   slot->advance.x / 64.0F, fprnt);
  else
    return 0;
}

CTypeFace *TypeFaceLoad(PyMOLGlobals * G, unsigned char *dat, unsigned int len)
{
  CType *I = G->Type;
  int ok = true;
  CTypeFace *result = pymol::calloc<CTypeFace>(1);
  if(result) {
    FT_Error error = FT_New_Memory_Face(I->library, dat, len, 0, &result->Face);
    result->G = G;
    if(error)
      ok = false;
    else {
      result->LastSize = 12.0F; /* default size */
      error = FT_Set_Char_Size(result->Face,    /* handle to face object */
                               0,       /* char_width in 1/64th of points */
                               (int) (result->LastSize * 64),   /* char_height in 1/64th of points */
                               72,      /* horizontal device resolution */
                               72);     /* vertical device resolution */

      if(error) {
        ok = false;
      } else {
        error = FT_Select_Charmap(result->Face, FT_ENCODING_UNICODE);
      }
    }
  }
  if(!ok) {
    FreeP(result);
  }
  return result;
}

float TypeFaceGetKerning(CTypeFace * I, unsigned int last, unsigned int current,
                         float size)
{
  float result = 0.0F;
  FT_UInt glyph_index, previous;
  /*  FT_Bool use_kerning = FT_HAS_KERNING( I->Face ); */
  FT_Bool use_kerning = 1;
  if(I->LastSize != size) {
    I->LastSize = size;
    FT_Set_Char_Size(I->Face,   /* handle to face object */
                     0,         /* char_width in 1/64th of points */
                     (int) (size * 64), /* char_height in 1/64th of points */
                     72,        /* horizontal device resolution */
                     72);       /* vertical device resolution */

  }
  if(use_kerning) {
    previous = FT_Get_Char_Index(I->Face, last);
    glyph_index = FT_Get_Char_Index(I->Face, current);
    if(previous && glyph_index) {
      FT_Vector delta;
      FT_Get_Kerning(I->Face, previous, glyph_index, FT_KERNING_DEFAULT, &delta);
      result = delta.x / 64.0F;
    }
  }
  return result;
}

void TypeFaceFree(CTypeFace * I)
{
  FT_Done_Face(I->Face);
  FreeP(I);
}

int TypeInit(PyMOLGlobals * G)
{
  CType *I;
  if((I = (G->Type = pymol::calloc<CType>(1)))) {
    FT_Error error = FT_Init_FreeType(&I->library);
    return !error;
  }
  return 0;
}

void TypeFree(PyMOLGlobals * G)
{
  CType *I = G->Type;
  FT_Done_FreeType(I->library);
  FreeP(G->Type);
}

float TypeFaceGetDescender(CTypeFace * I){
  return fabs(I->Face->descender/(float)I->Face->height);
}

#else

int TypeFaceCharacterNew(CTypeFace * I, CharFngrprnt * fprnt, float size)
{
  return 0;
}

float TypeFaceGetKerning(CTypeFace * I,
                         unsigned int last, unsigned int current, float size)
{
  return 0.0F;
}

CTypeFace *TypeFaceLoad(PyMOLGlobals * G, unsigned char *dat, unsigned int len)
{
  return nullptr;
}

void TypeFaceFree(CTypeFace * face)
{
}

int TypeInit(PyMOLGlobals * G)
{
  return 1;
}

void TypeFree(PyMOLGlobals * G)
{
}

float TypeFaceGetDescender(CTypeFace * I){
  return 0.f;
}

#endif