/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2002,2007 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992,2007 Frank Tore Johansen
 * 
 * Deliantra 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 3 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, see <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#include <cassert>

#include <global.h>
#include <loader.h>

#include <tr1/functional>
#include <tr1/unordered_map>

archetype *loading_arch; // ugly flag to object loader etc. to suppress/request special processing
arch_ptr archetype::empty;

// the hashtable
typedef std::tr1::unordered_map
  <
    const char *,
    arch_ptr,
    str_hash,
    str_equal,
    slice_allocator< std::pair<const char *const, arch_ptr> >
  > HT;

static HT ht (10000);
archvec archetypes;
static unordered_vector<archetype *> allarch;
static int dirtycnt;

// the vector of other_arch references to be resolved
static std::vector< std::pair<arch_ptr *, shstr> > postponed_arch_ref;
// the vector of loaded but not yet committed archetypes
static std::vector<archetype *> postponed_arch;

/**
 * GROS -  This function retrieves an archetype given the name that appears
 * during the game (for example, "writing pen" instead of "stylus").
 * It does not use the hashtable system, but browse the whole archlist each time.
 * I suggest not to use it unless you really need it because of performance issue.
 * It is currently used by scripting extensions (create-object).
 * Params:
 * - name: the name we're searching for (ex: "writing pen");
 * Return value:
 * - the archetype found or null if nothing was found.
 */
archetype *
find_archetype_by_object_name (const char *name)
{
  shstr_cmp name_cmp (name);

  for_all_archetypes (at)
    if (at->name == name_cmp)
      return at;

  return 0;
}

/**
 * This function retrieves an archetype by type and name that appears during
 * the game. It is basically the same as find_archetype_by_object_name()
 * except that it considers only items of the given type.
 */
archetype *
find_archetype_by_object_type_name (int type, const char *name)
{
  shstr_cmp name_cmp (name);

  for_all_archetypes (at)
    if (at->name == name_cmp && at->type == type)
      return at;

  return 0;
}

/* This is a lot like the above function.  Instead, we are trying to match
 * the arch->skill values.  type is the type of object to match
 * against (eg, to only match against skills or only skill objects for example).
 * If type is -1, ew don't match on type.
 */
object *
get_archetype_by_skill_name (const char *skill, int type)
{
  shstr_cmp skill_cmp (skill);

  for_all_archetypes (at)
    if (at->skill == skill_cmp && (type == -1 || type == at->type))
      return at->instance ();

  return 0;
}

/* similiar to above - this returns the first archetype
 * that matches both the type and subtype.  type and subtype
 * can be -1 to say ignore, but in this case, the match it does
 * may not be very useful.  This function is most useful when
 * subtypes are known to be unique for a particular type
 * (eg, skills)
 */
archetype *
get_archetype_by_type_subtype (int type, int subtype)
{
  for_all_archetypes (at)
    if ((type == -1 || type == at->type) && (subtype == -1 || subtype == at->subtype))
      return at;

  return 0;
}

/**
 * GROS - this returns a new object given the name that appears during the game
 * (for example, "writing pen" instead of "stylus").
 * Params:
 * - name: The name we're searching for (ex: "writing pen");
 * Return value:
 * - a corresponding object if found; a singularity object if not found.
 * Note by MSW - it appears that it takes the full name and keeps
 * shortening it until it finds a match.  I re-wrote this so that it
 * doesn't allocate it each time - not that this function is used much,
 * but it otherwise had a big memory leak.
 */
object *
get_archetype_by_object_name (const char *name)
{
  char tmpname[MAX_BUF];
  int i;

  assign (tmpname, name);

  for (i = strlen (tmpname); i > 0; i--)
    {
      tmpname[i] = 0;

      if (archetype *at = find_archetype_by_object_name (tmpname))
        return at->instance ();
    }

  return create_singularity (name);
}

/* This is a subset of the parse_id command.  Basically, name can be
 * a string seperated lists of things to match, with certain keywords.
 * pl is the player (only needed to set count properly)
 * op is the item we are trying to match.  Calling function takes care
 * of what action might need to be done and if it is valid
 * (pickup, drop, etc.)  Return NONZERO if we have a match.  A higher
 * value means a better match.  0 means no match.
 *
 * Brief outline of the procedure:
 * We take apart the name variable into the individual components.
 * cases for 'all' and unpaid are pretty obvious.
 * Next, we check for a count (either specified in name, or in the
 * player object.)
 * If count is 1, make a quick check on the name.
 * IF count is >1, we need to make plural name.  Return if match.
 * Last, make a check on the full name.
 */
int
item_matched_string (object *pl, object *op, const char *name)
{
  char *cp, local_name[MAX_BUF];
  int count, retval = 0;

  assign (local_name, name);    /* strtok is destructive to name */

  for (cp = strtok (local_name, ","); cp; cp = strtok (NULL, ","))
    {
      while (cp[0] == ' ')
        ++cp;                   /* get rid of spaces */

      /*      LOG(llevDebug,"Trying to match %s\n", cp); */
      /* All is a very generic match - low match value */
      if (!strcmp (cp, "all"))
        return 1;

      /* unpaid is a little more specific */
      if (!strcmp (cp, "unpaid") && QUERY_FLAG (op, FLAG_UNPAID))
        return 2;
      if (!strcmp (cp, "cursed") && QUERY_FLAG (op, FLAG_KNOWN_CURSED) && (QUERY_FLAG (op, FLAG_CURSED) || QUERY_FLAG (op, FLAG_DAMNED)))
        return 2;

      if (!strcmp (cp, "unlocked") && !QUERY_FLAG (op, FLAG_INV_LOCKED))
        return 2;

      /* Allow for things like '100 arrows' */
      if ((count = atoi (cp)) != 0)
        {
          cp = strchr (cp, ' ');
          while (cp && cp[0] == ' ')
            ++cp;               /* get rid of spaces */
        }
      else
        {
          if (pl->type == PLAYER)
            count = pl->contr->count;
          else
            count = 0;
        }

      if (!cp || cp[0] == '\0' || count < 0)
        return 0;


      /* The code here should go from highest retval to lowest.  That
       * is because of the 'else' handling - we don't want to match on
       * something and set a low retval, even though it may match a higher retcal
       * later.  So keep it in descending order here, so we try for the best
       * match first, and work downward.
       */
      if (!strcasecmp (cp, query_name (op)))
        retval = 20;
      else if (!strcasecmp (cp, query_short_name (op)))
        retval = 18;
      else if (!strcasecmp (cp, query_base_name (op, 0)))
        retval = 16;
      else if (!strcasecmp (cp, query_base_name (op, 1)))
        retval = 16;
      else if (op->custom_name && !strcasecmp (cp, op->custom_name))
        retval = 15;
      else if (!strncasecmp (cp, query_base_name (op, 0), strlen (cp)))
        retval = 14;
      else if (!strncasecmp (cp, query_base_name (op, 1), strlen (cp)))
        retval = 14;
      /* Do substring checks, so things like 'Str+1' will match.
       * retval of these should perhaps be lower - they are lower
       * then the specific strcasecmp aboves, but still higher than
       * some other match criteria.
       */
      else if (strstr (query_base_name (op, 1), cp))
        retval = 12;
      else if (strstr (query_base_name (op, 0), cp))
        retval = 12;
      else if (strstr (query_short_name (op), cp))
        retval = 12;
      /* Check against plural/non plural based on count. */
      else if (count > 1 && !strcasecmp (cp, op->name_pl))
        retval = 6;
      else if (count == 1 && !strcasecmp (op->name, cp))
        retval = 6;
      /* base name matched - not bad */
      else if (strcasecmp (cp, op->name) == 0 && !count)
        retval = 4;
      /* Check for partial custom name, but give a real low priority */
      else if (op->custom_name && strstr (op->custom_name, cp))
        retval = 3;

      if (retval)
        {
          if (pl->type == PLAYER)
            pl->contr->count = count;

          return retval;
        }
    }

  return 0;
}

archetype::archetype (const char *name)
{
  arch = this;
  this->archname = this->name = this->name_pl = name;
}

archetype::~archetype ()
{
  unlink ();
}

void
archetype::link ()
{
  if (!archetypes.contains (this))
    {
      archetypes.insert (this);
      ht.insert (std::make_pair (archname, this));
    }
}

void
archetype::unlink ()
{
  if (archetypes.contains (this))
    {
      archetypes.erase (this);
      ht.erase (archname);
    }
}

/*
 * Finds, using the hashtable, which archetype matches the given name.
 * returns a pointer to the found archetype, otherwise NULL.
 */
archetype *
archetype::find (const char *name)
{
  if (!name)
    return 0;

  auto (i, ht.find (name));

  if (i == ht.end ())
    return 0;
  else
    return i->second;
}

archetype *
archetype::read (object_thawer &f)
{
  assert (f.kw == KW_object);

  std::vector<archetype *> parts;

  coroapi::cede_to_tick ();

  for (;;)
    {
      archetype *at = new archetype (f.get_str ());

      f.next ();

#if 0
      // implementing it here in the server does neither allow multiple inheritence
      // nor does it cleanly "just override". it would allow use in map files, though,
      // and other resource files dynamically laoded (as opposed to being preprocessed).
      // not that any of this is relevant as of yet...
      if (f.kw == KW_inherit)
        {
          if (archetype *at = find (f.get_str ()))
            *op = at->clone;
          else
            LOG (llevError, "archetype '%s' tries to inherit from non-existent archetype '%s'.\n",
                 &at->archname, f.get_str ());

          f.next ();
        }
#endif

      loading_arch = at; // hack to tell parse_kv et al. to behave
      bool parse_ok = at->parse_kv (f);
      loading_arch = 0;

      if (!parse_ok)
        goto fail;

      loading_arch = at; // hack to tell parse_kv et al. to behave
      at->post_load_check ();
      loading_arch = 0;

      parts.push_back (at);

      if (f.kw != KW_more)
        break;

      f.next ();

      if (f.kw != KW_object)
        {
          f.parse_error ("more object");
          goto fail;
        }
    }

  {
    auto (at, parts.begin ());

    archetype *new_head = parts.front ();
    archetype *old_head = find (new_head->archname);

    if (old_head && !old_head->is_head ())
      {
        LOG (llevError, "%s: unable to overwrite non-head archetype '%s' with head archetype, skipping.\n",
             &new_head->archname, &old_head->archname);
        goto fail;
      }

    // check that all archetypes belong to the same old object or are new
    for (auto (at, parts.begin ()); at != parts.end (); ++at)
      {
        archetype *new_part = *at;
        archetype *old_part = find (new_part->archname);

        if (old_part && old_part->head_ () != old_head)
          {
            LOG (llevError, "%s: unable to overwrite archetype '%s' with archetype of different object, skipping.\n",
                 &new_part->archname, &((archetype *)old_part->head_ ())->archname);
            goto fail;
          }
      }

    // assemble new chain
    new_head->min_x = new_head->max_x = new_head->x;
    new_head->min_y = new_head->max_y = new_head->y;

    archetype *less = new_head;
    for (auto (p, parts.begin () + 1); p != parts.end (); ++p)
      {
        archetype *at = *p;

        // some flags get inherited from the head (probably a lot more)
        // doing it here doesn't feel too cozy, but it allows code
        // to ignore head checks for these flags, which saves time
        at->flag [FLAG_ALIVE]    = new_head->flag [FLAG_ALIVE];
        at->flag [FLAG_NO_PICK]  = new_head->flag [FLAG_NO_PICK];
        at->flag [FLAG_MONSTER]  = new_head->flag [FLAG_MONSTER];
        at->flag [FLAG_IS_FLOOR] = new_head->flag [FLAG_IS_FLOOR];

        new_head->min_x = min (new_head->min_x, at->x);
        new_head->min_y = min (new_head->min_y, at->y);
        new_head->max_x = max (new_head->max_x, at->x);
        new_head->max_y = max (new_head->max_y, at->y);

        at->head = new_head;
        less->more = at;
        less = at;
      }

    postponed_arch.insert (postponed_arch.end (), parts.begin (), parts.end ());

    return new_head;
  }

fail:
  for (auto (p, parts.begin ()); p != parts.end (); ++p)
    (*p)->destroy (true);

  return 0;
}

void
archetype::postpone_arch_ref (arch_ptr &ref, const_utf8_string other_arch)
{
  ref = 0;
  postponed_arch_ref.push_back (std::pair<arch_ptr *, shstr>(&ref, shstr (other_arch)));
}

void
archetype::commit_load ()
{
  // unlink old archetypes and link in new ones */
  for (auto (p, postponed_arch.begin ()); p != postponed_arch.end (); ++p)
    {
      archetype *at = *p;

      if (archetype *old = find (at->archname))
        old->unlink ();

      allarch.push_back (at);

      at->link ();
      ++dirtycnt;
    }

  postponed_arch.clear ();

  // now resolve arch references
  for (auto (p, postponed_arch_ref.begin ()); p != postponed_arch_ref.end (); ++p)
    {
      arch_ptr *ap = p->first;
      archetype *at = find (p->second);

      if (!at)
        LOG (llevError, "unable to resolve postponed arch reference to '%s'", &p->second);

      *ap = at;
    }

  postponed_arch_ref.clear ();

  empty = find (shstr_empty_archetype);
}

void
archetype::gc ()
{
  int cnt = max (1, min (allarch.size () / 128, dirtycnt));
  dirtycnt = max (0, dirtycnt - cnt);

  do
    {
      static int idx;

      if (idx >= allarch.size ())
        if (idx)
          idx = 0;
        else
          return;

      archetype *at = allarch [idx];

      if (at->refcnt_cnt () > 1) // all arches have ONE refcount from their object
        ++idx;
      else
        {
          LOG (llevDebug, "garbage collect arch %s", at->debug_desc ());
          assert (at->arch == at); // verify that refcnt == 1 is truly valid
          allarch.erase (idx);

          // break chain
          for (object *op = at->head_ (); op; )
            {
              object *next = op->more;
              op->head = 0;
              op->more = 0;
              op = next;
            }

          at->destroy ();
          at->arch = 0;
        }
    }
  while (--cnt);
}

/*
 * Creates and returns a new object which is a copy of the given archetype.
 * This function returns NULL on failure.
 */
object *
arch_to_object (archetype *at)
{
  if (!at)
    {
      LOG (llevError, "Couldn't find archetype.\n");
      return 0;
    }

  return at->instance ();
}

object *
archetype::instance ()
{
  object *op = clone ();
  op->instantiate ();
  return op;
}

/*
 * Creates an object.  This function is called by get_archetype()
 * if it fails to find the appropriate archetype.
 * Thus get_archetype() will be guaranteed to always return
 * an object, and never NULL.
 */
object *
create_singularity (const char *name)
{
  LOG (llevError | logBacktrace, "FATAL: creating singularity for '%s'.\n", name);

  if (!strcmp (name, "bug"))
    abort ();

  object *op = archetype::get ("bug");
  op->name = op->name_pl = format ("bug, please report (missing archetype %s)", name);

  return op;
}

/*
 * Finds which archetype matches the given name, and returns a new
 * object containing a copy of the archetype.
 */
object *
get_archetype (const char *name)
{
  return archetype::get (name);
}

object *
archetype::get (const char *name)
{
  archetype *at = find (name);

  if (!at)
    return create_singularity (name);

  return at->instance ();
}

/*
 * Returns the first archetype using the given type.
 * Used in treasure-generation.
 */
archetype *
type_to_archetype (int type)
{
  for_all_archetypes (at)
    if (at->type == type && at->head_ () != at)
      return at;

  return 0;
}

/*
 * Returns a new object copied from the first archetype matching
 * the given type.
 * Used in treasure-generation.
 */
object *
clone_arch (int type)
{
  archetype *at = type_to_archetype (type);

  if (!at)
    {
      LOG (llevError, "Can't clone archetype %d\n", type);
      return 0;
    }

  return at->instance ();
}

/*
 * member: make instance from class
 */
object *
object_create_arch (archetype *at)
{
  object *op, *prev = 0, *head = 0;

  while (at)
    {
      op = at->instance ();

      op->x = at->x;
      op->y = at->y;

      if (head)
        op->head = head, prev->more = op;

      if (!head)
        head = op;

      prev = op;
      at = (archetype *)at->more;
    }

  return head;
}