/*
    CrossFire, A Multiplayer game for X-windows

    Copyright (C) 2002-2003 Mark Wedel & Crossfire Development Team
    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 authors can be reached via e-mail at <crossfire@schmorp.de>
*/

/* This file contains animation related code. */

#include <global.h>
#include <stdio.h>

void
free_all_anim (void)
{
  for (int i = 0; i <= num_animations; i++)
    {
      animations[i].name = 0;
      free (animations[i].faces);
    }

  animations.clear ();
}

void
init_anim (void)
{
  char
    buf[MAX_BUF];
  FILE *
    fp;
  static int
    anim_init = 0;
  int
    num_frames = 0, faces[MAX_ANIMATIONS], i;

  if (anim_init)
    return;
  num_animations = 0;
  /* Make a default.  New animations start at one, so if something
   * thinks it is animated but hasn't set the animation_id properly,
   * it will have a default value that should be pretty obvious.
   */
  /* set the name so we don't try to dereferance null.
   * Put # at start so it will be first in alphabetical
   * order.
   */
  {
    Animations anim0;

    anim0.name = "###none";
    anim0.num_animations = 1;
    anim0.faces = (uint16 *)malloc (sizeof (uint16));
    anim0.faces[0] = 0;
    anim0.facings = 0;

    animations.push_back (anim0);
  }

  sprintf (buf, "%s/animations", settings.datadir);
  LOG (llevDebug, "Reading animations from %s...", buf);
  if ((fp = fopen (buf, "r")) == NULL)
    {
      LOG (llevError, "Cannot open animations file %s: %s\n", buf, strerror (errno));
      exit (-1);
    }
  while (fgets (buf, MAX_BUF - 1, fp) != NULL)
    {
      if (*buf == '#')
        continue;
      /* Kill the newline */
      buf[strlen (buf) - 1] = '\0';
      if (!strncmp (buf, "anim ", 5))
        {
          if (num_frames)
            {
              LOG (llevError, "Didn't get a mina before %s\n", buf);
              num_frames = 0;
            }
          num_animations++;

          Animations anim;

          anim.name = buf + 5;
          anim.num = num_animations;    /* for bsearch */
          anim.facings = 1;
          animations.push_back (anim);
        }
      else if (!strncmp (buf, "mina", 4))
        {
          animations[num_animations].faces = (uint16 *) malloc (sizeof (uint16) * num_frames);
          for (i = 0; i < num_frames; i++)
            animations[num_animations].faces[i] = faces[i];
          animations[num_animations].num_animations = num_frames;
          if (num_frames % animations[num_animations].facings)
            {
              LOG (llevDebug, "Animation %s frame numbers (%d) is not a multiple of facings (%d)\n",
                   &animations[num_animations].name, num_frames, animations[num_animations].facings);
            }
          num_frames = 0;
        }
      else if (!strncmp (buf, "facings", 7))
        {
          if (!(animations[num_animations].facings = atoi (buf + 7)))
            {
              LOG (llevDebug, "Animation %s has 0 facings, line=%s\n", &animations[num_animations].name, buf);
              animations[num_animations].facings = 1;
            }

        }
      else
        {
          if (!(faces[num_frames++] = FindFace (buf, 0)))
            LOG (llevDebug, "Could not find face %s for animation %s\n", buf, &animations[num_animations].name);
        }
    }
  fclose (fp);
  LOG (llevDebug, "done. got (%d)\n", num_animations);
}

static int
anim_compare (const Animations * a, const Animations * b)
{
  return strcmp (a->name, b->name);
}

/* Tries to find the animation id that matches name.  Returns an integer match 
 * 0 if no match found (animation 0 is initialized as the 'bug' face
 */
int
find_animation (const char *name)
{
  Animations
  search, *
    match;

  search.name = name;

  match = (Animations *) bsearch (&search, &animations[0], (num_animations + 1),
                                  sizeof (Animations), (int (*)(const void *, const void *)) anim_compare);


  if (match)
    return match->num;
  LOG (llevError, "Unable to find animation %s\n", name);
  return 0;
}

/*
 * animate_object(object) updates the face-variable of an object.
 * If the object is the head of a multi-object, all objects are animated.
 * op is the object to animate.
 * dir is the direction the object is facing.  This is generally same as
 *    op->direction, but in some cases, op->facing is used instead - the
 *    caller has a better idea which one it really wants to be using,
 *    so let it pass along the right one.
 */

void
animate_object (object *op, int dir)
{
  int max_state;                  /* Max animation state object should be drawn in */
  int base_state;                 /* starting index # to draw from */

  if (!op->animation_id || !NUM_ANIMATIONS (op))
    {
      LOG (llevError, "Object %s lacks animation.\n", op->debug_desc ());
      return;
    }

  if (op->head)
    {
      dir = op->head->direction;

      if (NUM_ANIMATIONS (op) == NUM_ANIMATIONS (op->head))
        op->state = op->head->state;
      else
        ++op->state;
    }
  else
    ++op->state;              /* increase draw state */

  /* If object is turning, then max animation state is half through the
   * animations.  Otherwise, we can use all the animations.
   */
  max_state = NUM_ANIMATIONS (op) / NUM_FACINGS (op);
  base_state = 0;
  /* at least in the older aniamtions that used is_turning, the first half
   * of the animations were left facing, the second half right facing.
   * Note in old the is_turning, it was set so that the animation for a monster
   * was always towards the enemy - now it is whatever direction the monster
   * is facing.
   */

  if (NUM_FACINGS (op) == 2)
    {
      if (dir < 5)
        base_state = 0;
      else
        base_state = NUM_ANIMATIONS (op) / 2;
    }
  else if (NUM_FACINGS (op) == 4)
    {
      if (dir == 0)
        base_state = 0;
      else
        base_state = ((dir - 1) / 2) * (NUM_ANIMATIONS (op) / 4);
    }
  else if (NUM_FACINGS (op) == 8)
    {
      if (dir == 0)
        base_state = 0;
      else
        base_state = (dir - 1) * (NUM_ANIMATIONS (op) / 8);
    }

  /* If beyond drawable states, reset */
  if (op->state >= max_state)
    op->state = 0;

  SET_ANIMATION (op, op->state + base_state);

  if (op->face == blank_face)
    op->invisible = 1;

  /* This block covers monsters (eg, pixies) which are supposed to
   * cycle from visible to invisible and back to being visible.
   * as such, disable it for players, as then players would become
   * visible.
   */
  else if (op->type != PLAYER && QUERY_FLAG ((&op->arch->clone), FLAG_ALIVE))
    {
      if (op->face->number == 0)
        {
          op->invisible = 1;
          CLEAR_FLAG (op, FLAG_ALIVE);
        }
      else
        {
          op->invisible = 0;
          SET_FLAG (op, FLAG_ALIVE);
        }
    }

  if (op->more)
    animate_object (op->more, dir);

  /* update_object will also recursively update all the pieces.
   * as such, we call it last, and only call it for the head
   * piece, and not for the other tail pieces.
   */
  if (!op->head)
    update_object (op, UP_OBJ_FACE);
}