/*----------------------------------------------------------------------*
 * ILBMW.C  Support routines for writing ILBM files using IFFParse.
 * (IFF is Interchange Format File.)
 *
 * Based on code by Jerry Morrison and Steve Shaw, Electronic Arts.
 * This software is in the public domain.
 *
 * This version for the Amiga computer.
 *----------------------------------------------------------------------*/

#include "iffp/ilbm.h"
#include "iffp/packer.h"

#include <graphics/gfxbase.h>

extern struct Library *GfxBase;

/*---------- initbmhd -------------------------------------------------*/
long initbmhd(BitMapHeader *bmhd, struct BitMap *bitmap,
              WORD masking, WORD compression, WORD transparentColor,
              WORD width, WORD height, WORD pageWidth, WORD pageHeight,
              ULONG modeid)
    {
    extern struct Library *GfxBase;
    struct DisplayInfo DI;

    WORD rowBytes = bitmap->BytesPerRow;

    D(bug("In InitBMHD\n"));

    bmhd->w = width;
    bmhd->h = height;
    bmhd->x = bmhd->y = 0;    /* Default position is (0,0).*/
    bmhd->nPlanes = bitmap->Depth;
    bmhd->masking = masking;
    bmhd->compression = compression;
    bmhd->reserved1 = 0;
    bmhd->transparentColor = transparentColor;
    bmhd->pageWidth = pageWidth;
    bmhd->pageHeight = pageHeight;

    bmhd->xAspect = 0;     /* So we can tell when we've got it */
    if(GfxBase->lib_Version >=36)
        {
        if(GetDisplayInfoData(NULL, (UBYTE *)&DI,
                sizeof(struct DisplayInfo), DTAG_DISP, modeid))
                {
                bmhd->xAspect =  DI.Resolution.x;
                bmhd->yAspect =  DI.Resolution.y;
                }
        }

    /* If running under 1.3 or GetDisplayInfoData failed, use old method
     * of guessing aspect ratio
     */
    if(! bmhd->xAspect)
        {
        bmhd->xAspect =  44;
        bmhd->yAspect =
                ((struct GfxBase *)GfxBase)->DisplayFlags & PAL ? 44 : 52;
        if(modeid & HIRES) bmhd->xAspect = bmhd->xAspect >> 1;
        if(modeid & LACE)  bmhd->yAspect = bmhd->yAspect >> 1;
        }

    return( IS_ODD(rowBytes) ? CLIENT_ERROR : IFF_OKAY );
    }

/*---------- putcmap ---------------------------------------------------*/
/* This function will accept a table of color values in one of the
 * following forms:
 *  if bitspergun=4,  colortable is words, each with nibbles 0RGB
 *  if bitspergun=8,  colortable is bytes of RGBRGB etc. (like a CMAP)
 *  if bitspergun=32, colortable is ULONGS of RGBRGB etc.
 *     (only the high eight bits of each gun will be written to CMAP)
 */
long putcmap(struct IFFHandle *iff, APTR colortable,
             UWORD ncolors, UWORD bitspergun)
   {
   long error, offs;
   WORD  *tabw;
   UBYTE *tab8;
   ColorRegister cmapReg;

   D(bug("In PutCMAP\n"));

   if((!iff)||(!colortable))    return(CLIENT_ERROR);

   /* size of CMAP is 3 bytes * ncolors */
   if(error = PushChunk(iff, NULL, ID_CMAP, ncolors * sizeofColorRegister))
        return(error);

   D(bug("Pushed ID_CMAP, error = %ld\n",error));

   if(bitspergun == 4)
        {
        /* Store each 4-bit value n as nn */
        tabw = (UWORD *)colortable;
        for( ;  ncolors;  --ncolors )
            {
            cmapReg.red    = ( *tabw >> 4 ) & 0xf0;
            cmapReg.red   |= (cmapReg.red >> 4);

            cmapReg.green  = ( *tabw      ) & 0xf0;
            cmapReg.green |= (cmapReg.green >> 4);

            cmapReg.blue   = ( *tabw << 4 ) & 0xf0;
            cmapReg.blue  |= (cmapReg.blue >> 4);

            if((WriteChunkBytes(iff, (BYTE *)&cmapReg, sizeofColorRegister))
                != sizeofColorRegister)
                        return(IFFERR_WRITE);
            ++tabw;
            }
        }
   else if((bitspergun == 8)||(bitspergun == 32))
        {
        tab8 = (UBYTE *)colortable;
        offs = (bitspergun == 8) ? 1 : 4;
        for( ;  ncolors;  --ncolors )
            {
            cmapReg.red   = *tab8;
            tab8 += offs;
            cmapReg.green = *tab8;
            tab8 += offs;
            cmapReg.blue  = *tab8;
            tab8 += offs;
            if((WriteChunkBytes(iff, (BYTE *)&cmapReg, sizeofColorRegister))
                != sizeofColorRegister)
                        return(IFFERR_WRITE);
            }
        }
   else (error = CLIENT_ERROR)

   D(bug("Wrote registers, error = %ld\n",error));

   error = PopChunk(iff);
   return(error);
   }

/*---------- putbody ---------------------------------------------------*/
/* NOTE: This implementation could be a LOT faster if it used more of the
 * supplied buffer. It would make far fewer calls to IFFWriteBytes (and
 * therefore to DOS Write). */
long putbody(struct IFFHandle *iff, struct BitMap *bitmap, BYTE *mask,
             BitMapHeader *bmhd, BYTE *buffer, LONG bufsize)
   {
   long error;
   LONG rowBytes = bitmap->BytesPerRow;
   int dstDepth = bmhd->nPlanes;
   UBYTE compression = bmhd->compression;
   int planeCnt;                /* number of bit planes including mask */
   register int iPlane, iRow;
   register LONG packedRowBytes;
   BYTE *buf;
   BYTE *planes[MAXSAVEDEPTH + 1]; /* array of ptrs to planes & mask */

   D(bug("In PutBODY\n"));

   if ( bufsize < MaxPackedSize(rowBytes)  ||      /* Must buffer a comprsd row*/
        compression > cmpByteRun1  ||              /* bad arg */
        bitmap->Rows != bmhd->h   ||          /* inconsistent */
        rowBytes != RowBytes(bmhd->w)  ||  /* inconsistent*/
        bitmap->Depth < dstDepth   ||         /* inconsistent */
        dstDepth > MAXSAVEDEPTH )          /* too many for this routine*/
      return(CLIENT_ERROR);

   planeCnt = dstDepth + (mask == NULL ? 0 : 1);

   /* Copy the ptrs to bit & mask planes into local array "planes" */
   for (iPlane = 0; iPlane < dstDepth; iPlane++)
      planes[iPlane] = (BYTE *)bitmap->Planes[iPlane];
   if (mask != NULL)
      planes[dstDepth] = mask;

   /* Write out a BODY chunk header */
   if(error = PushChunk(iff, NULL, ID_BODY, IFFSIZE_UNKNOWN)) return(error);

   /* Write out the BODY contents */
   for (iRow = bmhd->h; iRow > 0; iRow--)  {
      for (iPlane = 0; iPlane < planeCnt; iPlane++)  {

         /* Write next row.*/
         if (compression == cmpNone) {
            if(WriteChunkBytes(iff,planes[iPlane],rowBytes) != rowBytes)
                error = IFFERR_WRITE;
            planes[iPlane] += rowBytes;
            }

         /* Compress and write next row.*/
         else {
            buf = buffer;
            packedRowBytes = packrow(&planes[iPlane], &buf, rowBytes);
            if(WriteChunkBytes(iff,buffer,packedRowBytes) != packedRowBytes)
                error = IFFERR_WRITE;
            }

         if(error)      return(error);
         }
      }

   /* Finish the chunk */
   error = PopChunk(iff);
   return(error);
   }