{$ifndef ARM9}
  {$error Sprites are only available on the ARM9}
{$endif ARM9}

{$ifdef NDS_INTERFACE}

const
  ATTR0_NORMAL          = (0 shl 8);
  ATTR0_ROTSCALE        =	(1 shl 8);
  ATTR0_DISABLED        =	(2 shl 8);
  ATTR0_ROTSCALE_DOUBLE	= (3 shl 8);

  ATTR0_TYPE_NORMAL     = (0 shl 10);
  ATTR0_TYPE_BLENDED    =	(1 shl 10);
  ATTR0_TYPE_WINDOWED   = (2 shl 10);
  ATTR0_BMP             =	(3 shl 10);

  ATTR0_MOSAIC          = (1 shl 12);

  ATTR0_COLOR_16        = (0 shl 13); //16 color in tile mode...16 bit in bitmap mode
  ATTR0_COLOR_256       = (1 shl 13);

  ATTR0_SQUARE          = (0 shl 14);
  ATTR0_WIDE            = (1 shl 14);
  ATTR0_TALL            = (2 shl 14);

function OBJ_Y(m: cint): cint; inline;

function ATTR1_ROTDATA(n: cint): cint; inline;

const
  ATTR1_FLIP_X          = (1 shl 12);
  ATTR1_FLIP_Y          = (1 shl 13);
  ATTR1_SIZE_8          = (0 shl 14);
  ATTR1_SIZE_16         = (1 shl 14);
  ATTR1_SIZE_32         = (2 shl 14);
  ATTR1_SIZE_64         = (3 shl 14);

function OBJ_X(m: cint): cint; inline;

function ATTR2_PRIORITY(n: cint): cint; inline;     
function ATTR2_PALETTE(n: cint): cint; inline;      
function ATTR2_ALPHA(n: cint): cint; inline;		  

type 
  ObjBlendMode = (
    OBJMODE_NORMAL   = 0, 
    OBJMODE_BLENDED  = 1,
    OBJMODE_WINDOWED = 2,
    OBJMODE_BITMAP   = 3
  );

  ObjShape = (
    OBJSHAPE_SQUARE     = 0,
    OBJSHAPE_WIDE       = 1,
    OBJSHAPE_TALL       = 2,
    OBJSHAPE_FORBIDDEN  = 3
  );
  
  ObjSize = (
    OBJSIZE_8   = 0,
    OBJSIZE_16  = 1,
    OBJSIZE_32  = 2, 
    OBJSIZE_64  = 3
  );
  
  ObjColMode = (
    OBJCOLOR_16  = 0, 
    OBJCOLOR_256 = 1
  );

  ObjPriority = (
    OBJPRIORITY_0 = 0,
    OBJPRIORITY_1 = 1,
    OBJPRIORITY_2 = 2,
    OBJPRIORITY_3 = 3
  );

type
  // mimic gcc bitfields behaviour
  Unsigned_1  = 0..((1 shl 1)  - 1);
  Unsigned_2  = 0..((1 shl 2)  - 1);
  Unsigned_3  = 0..((1 shl 3)  - 1);
  Unsigned_4  = 0..((1 shl 4)  - 1);
  Unsigned_5  = 0..((1 shl 5)  - 1);
  Unsigned_6  = 0..((1 shl 6)  - 1);
  Unsigned_7  = 0..((1 shl 7)  - 1);
  Unsigned_8  = 0..((1 shl 8)  - 1);
  Unsigned_9  = 0..((1 shl 9)  - 1);
  Unsigned_10 = 0..((1 shl 10) - 1);

  sSpriteEntry = bitpacked record
    case integer of
      0: (
        y: Unsigned_8;//0..8;
        case integer of 
          0: (
  				  __padding1: Unsigned_1;//0..1;
  				  isHidden: Unsigned_1;//0..1;
  				  __padding2: Unsigned_6;//0..6;          
          );
          1: (
            isRotateScale: Unsigned_1;//0..1;
            isSizeDouble: Unsigned_1;//0..1;
            blendMode: Unsigned_2;//0..2;
            isMosaic: Unsigned_1;//0..1;
            colorMode: Unsigned_1;//0..1;
            shape: Unsigned_2;//0..2;          
//          );

            case integer of
              0: (
        			  x: Unsigned_9;//0..9;
                _padding3: Unsigned_7;//0..7;
              );
              1: (
                __padding4: Unsigned_8;//0..8;
                case integer of
                  0: (
    						    __padding5: Unsigned_4;//0..4;
    						    hFlip: Unsigned_1;//0..1;
    						    vFlip: Unsigned_1;//0..1;
    						    __padding6: Unsigned_2;//0..2;
                  );
                  1: (
    						    __padding7: Unsigned_1;//0..1;
    						    rotationIndex: Unsigned_5;//0..5;
    						    size: Unsigned_2;//0..2;
    //              );
    //          );
     
                    gfxIndex: Unsigned_10;//0..10;
                    priority: Unsigned_2;//0..2;
                    palette: Unsigned_4;//0..4;
                    
                    attribute3: cuint16;
                  );
              );     
          );
      ); 
      1: (
        attribute: array [0..2] of cuint16;
        filler: cuint16;   
      );
  end;
  SpriteEntry = sSpriteEntry;
  TSpriteEntry = sSpriteEntry;
  PSpriteEntry = ^sSpriteEntry;

  sSpriteRotation = record
    filler1: array [0..2] of cuint16;
    hdx: cint16;
    filler2: array [0..2] of cuint16;
    vdx: cint16;
    filler3: array [0..2] of cuint16;
    hdy: cint16;
    filler4: array [0..2] of cuint16;
    vdy: cint16;
  end;
  SpriteRotation = sSpriteRotation;
  TSpriteRotation = sSpriteRotation;
  pSpriteRotation = ^sSpriteRotation;


const
  SPRITE_COUNT = 128;
  MATRIX_COUNT = 32;

type
  OAMTable = record
    case integer of
      0: (
            oamBuffer: array [0..SPRITE_COUNT - 1] of TSpriteEntry;
      );
      1: (
            matrixBuffer: array [0..MATRIX_COUNT - 1] of TSpriteRotation;
      );
  end;
  TOAMTable = OAMTable;
  POAMTable = ^OAMTable;

type  
  SpriteSize = integer; 
const
  SpriteSize_8x8  : SpriteSize = (integer(OBJSIZE_8)  shl 14) or (integer(OBJSHAPE_SQUARE) shl 12) or ((8*8)   shr 5);
  SpriteSize_16x16: SpriteSize = (integer(OBJSIZE_16) shl 14) or (integer(OBJSHAPE_SQUARE) shl 12) or ((16*16) shr 5);
  SpriteSize_32x32: SpriteSize = (integer(OBJSIZE_32) shl 14) or (integer(OBJSHAPE_SQUARE) shl 12) or ((32*32) shr 5);
  SpriteSize_64x64: SpriteSize = (integer(OBJSIZE_64) shl 14) or (integer(OBJSHAPE_SQUARE) shl 12) or ((64*64) shr 5);
  SpriteSize_16x8 : SpriteSize = (integer(OBJSIZE_8)  shl 14) or (integer(OBJSHAPE_WIDE)   shl 12) or ((16*8)  shr 5);
  SpriteSize_32x8 : SpriteSize = (integer(OBJSIZE_16) shl 14) or (integer(OBJSHAPE_WIDE)   shl 12) or ((32*8)  shr 5);
  SpriteSize_32x16: SpriteSize = (integer(OBJSIZE_32) shl 14) or (integer(OBJSHAPE_WIDE)   shl 12) or ((32*16) shr 5);
  SpriteSize_64x32: SpriteSize = (integer(OBJSIZE_64) shl 14) or (integer(OBJSHAPE_WIDE)   shl 12) or ((64*32) shr 5);
  SpriteSize_8x16 : SpriteSize = (integer(OBJSIZE_8)  shl 14) or (integer(OBJSHAPE_TALL)   shl 12) or ((8*16)  shr 5);
  SpriteSize_8x32 : SpriteSize = (integer(OBJSIZE_16) shl 14) or (integer(OBJSHAPE_TALL)   shl 12) or ((8*32)  shr 5);
  SpriteSize_16x32: SpriteSize = (integer(OBJSIZE_32) shl 14) or (integer(OBJSHAPE_TALL)   shl 12) or ((16*32) shr 5);
  SpriteSize_32x64: SpriteSize = (integer(OBJSIZE_64) shl 14) or (integer(OBJSHAPE_TALL)   shl 12) or ((32*64) shr 5);  

function SPRITE_SIZE_SHAPE(size: cint): cuint32; inline;
function SPRITE_SIZE_SIZE(size: cint): cuint32; inline;
function SPRITE_SIZE_PIXELS(size: cint): cuint32; inline;


type
  TSpriteMapping = integer;
const
  SpriteMapping_1D_32     : TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_32)  or (0 shl 28) or 0;
  SpriteMapping_1D_64     : TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_64)  or (1 shl 28) or 1;
  SpriteMapping_1D_128    : TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_128) or (2 shl 28) or 2;
  SpriteMapping_1D_256    : TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_256) or (3 shl 28) or 3;
  SpriteMapping_2D        : TSpriteMapping = integer(DISPLAY_SPR_2D) or (4 shl 28);
  SpriteMapping_Bmp_1D_128: TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_128) or integer(DISPLAY_SPR_1D_BMP) or integer(DISPLAY_SPR_1D_BMP_SIZE_128) or (5 shl 28) or 2;
  SpriteMapping_Bmp_1D_256: TSpriteMapping = integer(DISPLAY_SPR_1D) or integer(DISPLAY_SPR_1D_SIZE_256) or integer(DISPLAY_SPR_1D_BMP) or integer(DISPLAY_SPR_1D_BMP_SIZE_256) or (6 shl 28) or 3;
  SpriteMapping_Bmp_2D_128: TSpriteMapping = integer(DISPLAY_SPR_2D) or integer(DISPLAY_SPR_2D_BMP_128)  or (7 shl 28) or 2;
  SpriteMapping_Bmp_2D_256: TSpriteMapping = integer(DISPLAY_SPR_2D) or integer(DISPLAY_SPR_2D_BMP_256)  or (8 shl 28) or 3;

type
  SpriteColorFormat = integer;
const 
  SpriteColorFormat_16Color : SpriteColorFormat = integer(OBJCOLOR_16);
  SpriteColorFormat_256Color: SpriteColorFormat = integer(OBJCOLOR_256);
  SpriteColorFormat_Bmp     : SpriteColorFormat = integer(OBJMODE_BITMAP);	 	 	 

  
type
  AllocHeader = record
    nextFree: cuint16;	    
    size: cuint16;
  end;  
  TAllocHeader = AllocHeader;
  PAllocHeader = ^AllocHeader;
  
  OamState = record
    gfxOffsetStep: cint; 
    firstFree: cint16;
    allocBuffer: PAllocHeader; 
    allocBufferSize: cint16;
    spriteMapping: TSpriteMapping;     
    case integer of
      0: (
            oamMemory: PSpriteEntry;
      ); 
      1: (
            oamRotationMemory: PSpriteRotation;
      );
  end;
  TOamState = OamState;
  POamState = ^OamState; 

var
  oamMain: OamState; cvar; external;
  oamSub: OamState; cvar; external;  

procedure oamInit(var oam: OamState; mapping: TSpriteMapping; extPalette: cbool); cdecl; external;
procedure oamDisable(var oam: OamState); cdecl; external;
procedure oamEnable(var oam: OamState); cdecl; external;
function oamGetGfxPtr(var oam: OamState; gfxOffsetIndex: cint): pcuint16; cdecl; external;
function oamAllocateGfx(var oam: OamState; size: SpriteSize; colorFormat: SpriteColorFormat): pcuint16; cdecl; external;
procedure oamFreeGfx(var oam: OamState; const gfxOffset: pointer); cdecl; external;

procedure oamSetMosaic(dx, dy: cuint); inline;
procedure oamSetMosaicSub(dx, dy: cuint); inline;

procedure oamSet( var oam: OamState; 
                  id, x, y, priority, palette_alpha: cint; 
                  size: SpriteSize; 
                  format: SpriteColorFormat; 
                  const gfxOffset: pointer; 
                  affineIndex: cint; 
                  sizeDouble, hide, hflip, vflip, mosaic: cbool); cdecl; external;
procedure oamClear(var oam: OamState; start, count: cint); cdecl; external;
procedure oamClearSprite(var oam: OamState; index: cint); inline;
procedure oamUpdate(var oam: OamState); cdecl; external;
procedure oamRotateScale(var oam: OamState; rotId, angle, sx, sy: cint); cdecl; external;
procedure oamAffineTransformation(var oam: OamState; rotId, hdx, hdy, vdx, vdy: cint); inline;

function oamCountFragments(var oam: OamState): cint; cdecl; external;
procedure oamAllocReset(var oam: OamState); cdecl; external;
function oamGfxPtrToOffset(var oam: OamState; const offset: pointer): cuint; cdecl; external;
{$endif NDS_INTERFACE}
 
{$ifdef NDS_IMPLEMENTATION}
function OBJ_Y(m: cint): cint; inline;
begin
  OBJ_Y := ((m) and $00ff);
end;

function ATTR1_ROTDATA(n: cint): cint; inline;
begin
  ATTR1_ROTDATA := ((n) shl 9)  // note: overlaps with flip flags
end;

function OBJ_X(m: cint): cint; inline;
begin
  OBJ_X := ((m) and $01ff);
end;

function ATTR2_PRIORITY(n: cint): cint; inline;     
begin
  ATTR2_PRIORITY := ((n) shl 10);
end;

function ATTR2_PALETTE(n: cint): cint; inline;      
begin
  ATTR2_PALETTE := ((n) shl 12);
end;

function ATTR2_ALPHA(n: cint): cint; inline;		  
begin
  ATTR2_ALPHA := ((n) shl 12);
end;

function SPRITE_SIZE_SHAPE(size: cint): cuint32; inline;
begin
  SPRITE_SIZE_SHAPE := (((size) shr 12) and $3);
end;

function SPRITE_SIZE_SIZE(size: cint): cuint32; inline;
begin
  SPRITE_SIZE_SIZE := (((size) shr 14) and $3);
end;

function SPRITE_SIZE_PIXELS(size: cint): cuint32; inline;
begin
  SPRITE_SIZE_PIXELS := (((size) and $FFF) shl 5);
end;

procedure oamSetMosaic(dx, dy: cuint); inline;
begin
  sassert((dx < 16) and (dy < 16), 'Mosaic range must be 0 to 15');
  mosaicShadow := ( mosaicShadow and $00ff) or (dx shl 8) or (dy shl 12);
  REG_MOSAIC^ := mosaicShadow;
end;

procedure oamSetMosaicSub(dx, dy: cuint); inline;
begin
  sassert((dx < 16) and (dy < 16), 'Mosaic range must be 0 to 15');
  mosaicShadowSub := (mosaicShadowSub and $00ff) or (dx shl 8) or (dy shl 12);
  REG_MOSAIC_SUB^ := mosaicShadowSub;
end;

procedure oamClearSprite(var oam: OamState; index: cint); inline;
begin
  sassert( (index >= 0) and (index < SPRITE_COUNT), 'oamClearSprite() index is out of bounds, must be 0-127');
  oam.oamMemory[index].attribute[0] := ATTR0_DISABLED;
end;

procedure oamAffineTransformation(var oam: OamState; rotId, hdx, hdy, vdx, vdy: cint); inline;
begin
  sassert((rotId >= 0) and (rotId < 32), 'oamAffineTransformation() rotId is out of bounds, must be 0-31');
  oam.oamRotationMemory[rotId].hdx := hdx;
  oam.oamRotationMemory[rotId].vdx := vdx;
  oam.oamRotationMemory[rotId].hdy := hdy;
  oam.oamRotationMemory[rotId].vdy := vdy;
end;


{$endif NDS_IMPLEMENTATION}