/* $Id: tif_tile.c,v 1.4 2005/11/19 16:02:59 malaterre Exp $ */

/*
 * Copyright (c) 1991-1997 Sam Leffler
 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and 
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 * 
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
 * 
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
 * OF THIS SOFTWARE.
 */

/*
 * TIFF Library.
 *
 * Tiled Image Support Routines.
 */
#include "tiffiop.h"

static uint32
summarize(TIFF* tif, size_t summand1, size_t summand2, const char* where)
{
  /*
   * XXX: We are using casting to uint32 here, bacause sizeof(size_t)
   * may be larger than sizeof(uint32) on 64-bit architectures.
   */
  uint32  bytes = summand1 + summand2;

  if (bytes - summand1 != summand2) {
    TIFFError(tif->tif_name, "Integer overflow in %s", where);
    bytes = 0;
  }

  return (bytes);
}

static uint32
multiply(TIFF* tif, size_t nmemb, size_t elem_size, const char* where)
{
  uint32  bytes = nmemb * elem_size;

  if (elem_size && bytes / elem_size != nmemb) {
    TIFFError(tif->tif_name, "Integer overflow in %s", where);
    bytes = 0;
  }

  return (bytes);
}

/*
 * Compute which tile an (x,y,z,s) value is in.
 */
ttile_t
TIFFComputeTile(TIFF* tif, uint32 x, uint32 y, uint32 z, tsample_t s)
{
  TIFFDirectory *td = &tif->tif_dir;
  uint32 dx = td->td_tilewidth;
  uint32 dy = td->td_tilelength;
  uint32 dz = td->td_tiledepth;
  ttile_t tile = 1;

  if (td->td_imagedepth == 1)
    z = 0;
  if (dx == (uint32) -1)
    dx = td->td_imagewidth;
  if (dy == (uint32) -1)
    dy = td->td_imagelength;
  if (dz == (uint32) -1)
    dz = td->td_imagedepth;
  if (dx != 0 && dy != 0 && dz != 0) {
    uint32 xpt = TIFFhowmany(td->td_imagewidth, dx); 
    uint32 ypt = TIFFhowmany(td->td_imagelength, dy); 
    uint32 zpt = TIFFhowmany(td->td_imagedepth, dz); 

    if (td->td_planarconfig == PLANARCONFIG_SEPARATE) 
      tile = (xpt*ypt*zpt)*s +
           (xpt*ypt)*(z/dz) +
           xpt*(y/dy) +
           x/dx;
    else
      tile = (xpt*ypt)*(z/dz) + xpt*(y/dy) + x/dx;
  }
  return (tile);
}

/*
 * Check an (x,y,z,s) coordinate
 * against the image bounds.
 */
int
TIFFCheckTile(TIFF* tif, uint32 x, uint32 y, uint32 z, tsample_t s)
{
  TIFFDirectory *td = &tif->tif_dir;

  if (x >= td->td_imagewidth) {
    TIFFError(tif->tif_name, "%lu: Col out of range, max %lu",
        (unsigned long) x, (unsigned long) td->td_imagewidth);
    return (0);
  }
  if (y >= td->td_imagelength) {
    TIFFError(tif->tif_name, "%lu: Row out of range, max %lu",
        (unsigned long) y, (unsigned long) td->td_imagelength);
    return (0);
  }
  if (z >= td->td_imagedepth) {
    TIFFError(tif->tif_name, "%lu: Depth out of range, max %lu",
        (unsigned long) z, (unsigned long) td->td_imagedepth);
    return (0);
  }
  if (td->td_planarconfig == PLANARCONFIG_SEPARATE &&
      s >= td->td_samplesperpixel) {
    TIFFError(tif->tif_name, "%lu: Sample out of range, max %lu",
        (unsigned long) s, (unsigned long) td->td_samplesperpixel);
    return (0);
  }
  return (1);
}

/*
 * Compute how many tiles are in an image.
 */
ttile_t
TIFFNumberOfTiles(TIFF* tif)
{
  TIFFDirectory *td = &tif->tif_dir;
  uint32 dx = td->td_tilewidth;
  uint32 dy = td->td_tilelength;
  uint32 dz = td->td_tiledepth;
  ttile_t ntiles;

  if (dx == (uint32) -1)
    dx = td->td_imagewidth;
  if (dy == (uint32) -1)
    dy = td->td_imagelength;
  if (dz == (uint32) -1)
    dz = td->td_imagedepth;
  ntiles = (dx == 0 || dy == 0 || dz == 0) ? 0 :
      multiply(tif, multiply(tif, TIFFhowmany(td->td_imagewidth, dx),
           TIFFhowmany(td->td_imagelength, dy),
           "TIFFNumberOfTiles"),
         TIFFhowmany(td->td_imagedepth, dz), "TIFFNumberOfTiles");
  if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
    ntiles = multiply(tif, ntiles, td->td_samplesperpixel,
          "TIFFNumberOfTiles");
  return (ntiles);
}

/*
 * Compute the # bytes in each row of a tile.
 */
tsize_t
TIFFTileRowSize(TIFF* tif)
{
  TIFFDirectory *td = &tif->tif_dir;
  tsize_t rowsize;
  
  if (td->td_tilelength == 0 || td->td_tilewidth == 0)
    return ((tsize_t) 0);
  rowsize = multiply(tif, td->td_bitspersample, td->td_tilewidth,
         "TIFFTileRowSize");
  if (td->td_planarconfig == PLANARCONFIG_CONTIG)
    rowsize = multiply(tif, rowsize, td->td_samplesperpixel,
           "TIFFTileRowSize");
  return ((tsize_t) TIFFhowmany8(rowsize));
}

/*
 * Compute the # bytes in a variable length, row-aligned tile.
 */
tsize_t
TIFFVTileSize(TIFF* tif, uint32 nrows)
{
  TIFFDirectory *td = &tif->tif_dir;
  tsize_t tilesize;

  if (td->td_tilelength == 0 || td->td_tilewidth == 0 ||
      td->td_tiledepth == 0)
    return ((tsize_t) 0);
  if (td->td_planarconfig == PLANARCONFIG_CONTIG &&
      td->td_photometric == PHOTOMETRIC_YCBCR &&
      !isUpSampled(tif)) {
    /*
     * Packed YCbCr data contain one Cb+Cr for every
     * HorizontalSampling*VerticalSampling Y values.
     * Must also roundup width and height when calculating
     * since images that are not a multiple of the
     * horizontal/vertical subsampling area include
     * YCbCr data for the extended image.
     */
    tsize_t w =
        TIFFroundup(td->td_tilewidth, td->td_ycbcrsubsampling[0]);
    tsize_t rowsize =
        TIFFhowmany8(multiply(tif, w, td->td_bitspersample,
            "TIFFVTileSize"));
    tsize_t samplingarea =
        td->td_ycbcrsubsampling[0]*td->td_ycbcrsubsampling[1];
    if (samplingarea == 0) {
      TIFFError(tif->tif_name, "Invalid YCbCr subsampling");
      return 0;
    }
    nrows = TIFFroundup(nrows, td->td_ycbcrsubsampling[1]);
    /* NB: don't need TIFFhowmany here 'cuz everything is rounded */
    tilesize = multiply(tif, nrows, rowsize, "TIFFVTileSize");
    tilesize = summarize(tif, tilesize,
             multiply(tif, 2, tilesize / samplingarea,
                "TIFFVTileSize"),
             "TIFFVTileSize");
  } else
    tilesize = multiply(tif, nrows, TIFFTileRowSize(tif),
            "TIFFVTileSize");
  return ((tsize_t)
      multiply(tif, tilesize, td->td_tiledepth, "TIFFVTileSize"));
}

/*
 * Compute the # bytes in a row-aligned tile.
 */
tsize_t
TIFFTileSize(TIFF* tif)
{
  return (TIFFVTileSize(tif, tif->tif_dir.td_tilelength));
}

/*
 * Compute a default tile size based on the image
 * characteristics and a requested value.  If a
 * request is <1 then we choose a size according
 * to certain heuristics.
 */
void
TIFFDefaultTileSize(TIFF* tif, uint32* tw, uint32* th)
{
  (*tif->tif_deftilesize)(tif, tw, th);
}

void
_TIFFDefaultTileSize(TIFF* tif, uint32* tw, uint32* th)
{
  (void) tif;
  if (*(int32*) tw < 1)
    *tw = 256;
  if (*(int32*) th < 1)
    *th = 256;
  /* roundup to a multiple of 16 per the spec */
  if (*tw & 0xf)
    *tw = TIFFroundup(*tw, 16);
  if (*th & 0xf)
    *th = TIFFroundup(*th, 16);
}

