/*
 * CrossFire, A Multiplayer game
 *
 * Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
 * Copyright (C) 2001 Mark Wedel
 * Copyright (C) 1992 Frank Tore Johansen
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * The author can be reached via e-mail to <crossfire@schmorp.de>
 */

/** \file
 * Image related communication
 *
 *  \date 2003-12-02
 *
 * This file deals with the image related communication to the
 * client.  I've located all the functions in this file - this
 * localizes it more, and means that we don't need to declare
 * things like all the structures as globals.
 */

#include <global.h>
#include <sproto.h>

#include "crc.h"

#define MAX_FACE_SETS	20  /**< Maximum number of image sets the program will handle */

/** Information about one image */
typedef struct FaceInfo
{
  uint8 *data;              /**< image data */
  uint16 datalen;           /**< length of the xpm data */
  uint32 checksum;          /**< Checksum of face data */
} FaceInfo;

/** Information about one face set */
typedef struct
{
  char *prefix;         /**< */
  char *fullname;

  uint8 fallback;       /**< faceset to use when an image is not found in this faceset */
  char *size;
  char *extension;
  char *comment;

  FaceInfo *faces;      /**< images in this faceset */
} FaceSets;

static FaceSets facesets[MAX_FACE_SETS];    /**< All facesets */

/**
 * Checks specified faceset is valid
 * \param fsn faceset number
 */
int
is_valid_faceset (int fsn)
{
  if (fsn >= 0 && fsn < MAX_FACE_SETS && facesets[fsn].prefix)
    return TRUE;
  return FALSE;
}

/**
 * Frees all faceset information
 */
void
free_socket_images (void)
{
  int num, q;

  for (num = 0; num < MAX_FACE_SETS; num++)
    {
      if (facesets[num].prefix)
        {
          for (q = 0; q < nrofpixmaps; q++)
            if (facesets[num].faces[q].data)
              free (facesets[num].faces[q].data);

          free (facesets[num].prefix);
          free (facesets[num].fullname);
          free (facesets[num].size);
          free (facesets[num].extension);
          free (facesets[num].comment);
          free (facesets[num].faces);
        }
    }
}

/**
 * This returns the set we will actually use when sending
 * a face.  This is used because the image files may be sparse.
 * This function is recursive.  imageno is the face number we are
 * trying to send
 *
 * If face is not found in specified faceset, tries with 'fallback' faceset.
 *
 * \param faceset faceset to check
 * \param imageno image number
 *
 */
static int
get_face_fallback (int faceset, int imageno)
{
  /* faceset 0 is supposed to have every image, so just return.  Doing
   * so also prevents infinite loops in the case if it not having
   * the face, but in that case, we are likely to crash when we try
   * to access the data, but that is probably preferable to an infinite
   * loop.
   */
  if (faceset == 0)
    return 0;

  if (!facesets[faceset].prefix)
    {
      LOG (llevError, "get_face_fallback called with unused set (%d)?\n", faceset);
      return 0;                 /* use default set */
    }

  if (facesets[faceset].faces[imageno].data)
    return faceset;

  return get_face_fallback (facesets[faceset].fallback, imageno);
}

/**
 * Checks fallback are correctly defined.
 * This is a simple recursive function that makes sure the fallbacks
 * are all proper (eg, the fall back to defined sets, and also
 * eventually fall back to 0).  At the top level, togo is set to MAX_FACE_SETS,
 * if togo gets to zero, it means we have a loop.
 * This is only run when we first load the facesets.
 */
static void
check_faceset_fallback (int faceset, int togo)
{
  int fallback = facesets[faceset].fallback;

  /* proper case - falls back to base set */
  if (fallback == 0)
    return;

  if (!facesets[fallback].prefix)
    {
      LOG (llevError, "Face set %d falls to non set faceset %d\n", faceset, fallback);
      abort ();
    }

  togo--;
  if (togo == 0)
    {
      LOG (llevError, "Infinite loop found in facesets. aborting.\n");
      abort ();
    }

  check_faceset_fallback (fallback, togo);
}

#define MAX_IMAGE_SIZE 10000

/**
 * Loads all the image types into memory.
 *
 *  This  way, we can easily send them to the client.  We should really do something
 * better than abort on any errors - on the other hand, these are all fatal
 * to the server (can't work around them), but the abort just seems a bit
 * messy (exit would probably be better.)
 *
 * Couple of notes:  We assume that the faces are in a continous block.
 * This works fine for now, but this could perhaps change in the future
 *
 * Function largely rewritten May 2000 to be more general purpose.
 * The server itself does not care what the image data is - to the server,
 * it is just data it needs to allocate.  As such, the code is written
 * to do such.
 */
void
read_client_images (void)
{
  char filename[400];
  char buf[HUGE_BUF];
  char *cp, *cps[7];
  FILE *infile;
  int num, len, compressed, fileno, i, badline;

  memset (facesets, 0, sizeof (facesets));
  sprintf (filename, "%s/image_info", settings.datadir);
  if ((infile = open_and_uncompress (filename, 0, &compressed)) == NULL)
    {
      LOG (llevError, "Unable to open %s\n", filename);
      abort ();
    }

  while (fgets (buf, HUGE_BUF - 1, infile) != NULL)
    {
      badline = 0;

      if (buf[0] == '#')
        continue;

      if (!(cps[0] = strtok (buf, ":")))
        badline = 1;

      for (i = 1; i < 7; i++)
        if (!(cps[i] = strtok (NULL, ":")))
          badline = 1;

      if (badline)
        LOG (llevError, "Bad line in image_info file, ignoring line:\n  %s", buf);
      else
        {
          len = atoi (cps[0]);
          if (len >= MAX_FACE_SETS)
            {
              LOG (llevError, "To high a setnum in image_info file: %d > %d\n", len, MAX_FACE_SETS);
              abort ();
            }
          facesets[len].prefix = strdup (cps[1]);
          facesets[len].fullname = strdup (cps[2]);
          facesets[len].fallback = atoi (cps[3]);
          facesets[len].size = strdup (cps[4]);
          facesets[len].extension = strdup (cps[5]);
          facesets[len].comment = strdup (cps[6]);
        }
    }

  close_and_delete (infile, compressed);

  for (i = 0; i < MAX_FACE_SETS; i++)
    {
      if (facesets[i].prefix)
        check_faceset_fallback (i, MAX_FACE_SETS);
    }

  /* Loaded the faceset information - now need to load up the
   * actual faces.
   */

  for (fileno = 0; fileno < MAX_FACE_SETS; fileno++)
    {
      /* if prefix is not set, this is not used */
      if (!facesets[fileno].prefix)
        continue;

      facesets[fileno].faces = (FaceInfo *) calloc (nrofpixmaps, sizeof (FaceInfo));

      sprintf (filename, "%s/crossfire.%d", settings.datadir, fileno);
      LOG (llevDebug, "Loading image file %s\n", filename);

      if ((infile = open_and_uncompress (filename, 0, &compressed)) == NULL)
        {
          LOG (llevError, "Unable to open %s\n", filename);
          abort ();
        }

      while (fgets (buf, HUGE_BUF - 1, infile) != NULL)
        {
          if (strncmp (buf, "IMAGE ", 6) != 0)
            {
              LOG (llevError, "read_client_images:Bad image line - not IMAGE, instead\n%s", buf);
              abort ();
            }

          num = atoi (buf + 6);
          if (num < 0 || num >= nrofpixmaps)
            {
              LOG (llevError, "read_client_images: Image num %d not in 0..%d\n%s", num, nrofpixmaps, buf);
              abort ();
            }

          /* Skip accross the number data */
          for (cp = buf + 6; *cp != ' '; cp++)
            ;

          len = atoi (cp);
          if (len == 0 || len > MAX_IMAGE_SIZE)
            {
              LOG (llevError, "read_client_images: length not valid: %d > %d \n%s", len, MAX_IMAGE_SIZE, buf);
              abort ();
            }

          /* We don't actualy care about the name of the image that
           * is embedded in the image file, so just ignore it.
           */
          facesets[fileno].faces[num].datalen = len;
          facesets[fileno].faces[num].data = (uint8 *) malloc (len);
          if ((i = fread (facesets[fileno].faces[num].data, len, 1, infile)) != 1)
            {
              LOG (llevError, "read_client_images: Did not read desired amount of data, wanted %d, got %d\n%s", len, i, buf);
              abort ();
            }

          crc32 chksum;

          for (i = 0; i < len; i++)
            chksum (facesets[fileno].faces[num].data[i]);

          facesets[fileno].faces[num].checksum = chksum;
        }

      close_and_delete (infile, compressed);
    }                           /* For fileno < MAX_FACE_SETS */
}

/**
 * Client tells us what type of faces it wants.  Also sets
 * the caching attribute.
 *
 */
void
SetFaceMode (char *buf, int len, client *ns)
{
  int mask = (atoi (buf) & CF_FACE_CACHE), mode = (atoi (buf) & ~CF_FACE_CACHE);

  if (mode == CF_FACE_NONE)
    ns->facecache = 1;
  else if (mode != CF_FACE_PNG)
    ns->send_packet_printf ("drawinfo %d %s", NDI_RED, "Warning - send unsupported face mode.  Will use Png");

  if (mask)
    ns->facecache = 1;
}

/**
 * Client has requested pixmap that it somehow missed getting.
 * This will be called often if the client is
 * caching images.
 */
void
SendFaceCmd (char *buf, int len, client *ns)
{
  uint16 facenum = atoi (buf);

  if (facenum != 0)
    esrv_send_face (ns, facenum, 1);
}

/**
 * Sends a face to a client if they are in pixmap mode
 * nothing gets sent in bitmap mode. 
 * If nocache is true (nonzero), ignore the cache setting from the client -
 * this is needed for the askface, in which we really do want to send the
 * face (and askface is the only place that should be setting it).  Otherwise,
 * we look at the facecache, and if set, send the image name.
 */
void
esrv_send_face (client *ns, short face_num, int nocache)
{
  char fallback;

  if (face_num <= 0 || face_num >= nrofpixmaps)
    {
      LOG (llevError, "esrv_send_face (%d) out of bounds??\n", face_num);
      return;
    }

  packet sl;
  fallback = get_face_fallback (ns->faceset, face_num);

  if (facesets[fallback].faces[face_num].data == NULL)
    {
      LOG (llevError, "esrv_send_face: faces[%d].data == NULL\n", face_num);
      return;
    }

  if (ns->facecache && !nocache)
    {
      sl << (ns->image2 ? "face2 " : "face1 ")
         << uint16 (face_num);

      if (ns->image2)
        sl << uint8 (fallback);

      sl << uint32 (facesets[fallback].faces[face_num].checksum)
         << new_faces[face_num].name;

      ns->send_packet (sl);
    }
  else
    {
      sl << (ns->image2 ? "image2 " : "image ")
         << uint32 (face_num);

      if (ns->image2)
        sl << uint8 (fallback);

      sl << uint32 (facesets[fallback].faces[face_num].datalen)
         << data (facesets[fallback].faces[face_num].data, facesets[fallback].faces[face_num].datalen);

      ns->send_packet (sl);
    }

  ns->faces_sent[face_num] |= NS_FACESENT_FACE;
}

/**
 * Sends the number of images, checksum of the face file,
 * and the image_info file information.  See the doc/Developers/protocol
 * if you want further detail.
 */

void
send_image_info (client *ns, char *params)
{
  packet sl;

  sl.printf ("replyinfo image_info\n%d\n%u\n", nrofpixmaps - 1, (unsigned int)bmaps_checksum);

  for (int i = 0; i < MAX_FACE_SETS; i++)
    if (facesets[i].prefix)
      sl.printf ("%d:%s:%s:%d:%s:%s:%s", i,
                 facesets[i].prefix, facesets[i].fullname , facesets[i].fallback,
                 facesets[i].size  , facesets[i].extension, facesets[i].comment);

  ns->send_packet (sl);
}

/**
 * Sends requested face information.
 * \param ns socket to send to
 * \param params contains first and last index of face
 *
 * For each image in [start..stop] sends
 *  - checksum
 *  - name
 */
void
send_image_sums (client *ns, char *params)
{
  int start, stop;
  char *cp, buf[MAX_BUF];

  packet sl;

  start = atoi (params);
  for (cp = params; *cp != '\0'; cp++)
    if (*cp == ' ')
      break;

  stop = atoi (cp);
  if (stop < start || *cp == '\0' || (stop - start) > 1000 || stop >= nrofpixmaps)
    {
      sl.printf ("replyinfo image_sums %d %d", start, stop);
      ns->send_packet (sl);
      sl.reset ();
      return;
    }

  sl.printf ("replyinfo image_sums %d %d ", start, stop);

  for (int i = start; i <= stop; i++)
    {
      ns->faces_sent[i] |= NS_FACESENT_FACE;

      int qq = get_face_fallback (ns->faceset, i);

      sl << uint16 (i)
         << uint32 (facesets[qq].faces[i].checksum)
         << uint8  (qq)
         << data8  (&new_faces[i].name, new_faces[i].name.length () + 1);
    }

  /* It would make more sense to catch this pre-emptively in the code above.
   * however, if this really happens, we probably just want to cut down the
   * size to less than 1000, since that is what we claim the protocol would
   * support.
   */
  if (sl.length () >= MAXSOCKBUF)
    {
      LOG (llevError, "send_image_send: buffer overrun, %d > %d\n", sl.length (), MAXSOCKBUF);
      abort ();
    }

  ns->send_packet (sl);
}