/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2006,2007,2008,2009,2010,2011 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * 
 * Deliantra is free software: you can redistribute it and/or modify it under
 * the terms of the Affero 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 Affero GNU General Public License
 * and 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 "global.h" // bug in cfperl.h, doesn't include interface_class stuff
#include "logger.h"
#include "cfperl.h"
#include "kw_hash.h"

object_freezer::object_freezer ()
: dynbuf_text (128 * 1024, 64 * 1024)
{
  av = newAV ();
}

object_freezer::~object_freezer ()
{
  SvREFCNT_dec (av);
}

void
object_freezer::put_ (attachable *ext)
{
  ext->optimise ();

  if (ext->self)
    {
      int idx = AvFILLp ((AV *)av) + 1;
      av_store (av, idx, newRV_inc ((SV *)ext->self));

      put (KW(oid), sint32(idx));
    }
}

bool
object_freezer::save (const char *path)
{
  CALL_BEGIN (3);
  CALL_ARG_SV (newSVpv (path, 0));
  CALL_ARG_SV (newRV_noinc (newSVpvn ((char *)linearise (), size ())));
  CALL_ARG_SV (newRV_inc ((SV *)av));
  CALL_CALL ("cf::object_freezer_save", G_VOID | G_DISCARD);
  CALL_END;

  return 1;
}

char *
object_freezer::as_string ()
{
  CALL_BEGIN (2);
  CALL_ARG_SV (newRV_noinc (newSVpvn ((char *)linearise (), size ())));
  CALL_ARG_SV (newRV_inc ((SV *)av));
  CALL_CALL ("cf::object_freezer_as_string", G_SCALAR);

  char *res = count > 0
                ? strdup (SvPVX (POPs))
                : strdup ("[fatal error]");

  CALL_END;

  return res;
}

#if 0
void
fprintf (object_freezer &freezer, const char *format, ...)
{
  va_list ap;

  va_start (ap, format);

  int len = vsnprintf ((char *)freezer.force (1024), 1024, format, ap);

  if (len >= 0)
    freezer.alloc (len);

  va_end (ap);
}

// XXX: function not returning an int
void
fputs (const char *s, object_freezer &freezer)
{
  freezer.add (s);
}
#endif

static const char thawer_eof[] = "\n\n\n\0\0\0";

bool object_thawer::errors_are_fatal = true;

object_thawer::object_thawer (const char *data, AV *perlav)
: name (strdup ("(memory stream)"))
{
  init ("(memory stream)");

  av   = perlav;
  text = newSVpv (data, 0); sv_catpv (text, thawer_eof);
  line = SvPVbyte_nolen (text);
  next ();
}

object_thawer::object_thawer (const_utf8_string path)
{
  init_from_file (path);
}

// convenience constructor
object_thawer::object_thawer (const_utf8_string dir, const_utf8_string file)
{
  init_from_file (format ("%s/%s", dir, file));
}

void
object_thawer::init (const_utf8_string path)
{
  name    = strdup (path);
  av      = 0;
  text    = 0;
  line    = 0;
  linenum = 0;

  kw      = KW_ERROR;
  kw_str  = 0;
  value   = 0;
}

void
object_thawer::init_from_file (const_utf8_string path)
{
  init (path);

  CALL_BEGIN (1);
  CALL_ARG_SV (newSVpv (path, 0));
  CALL_CALL ("cf::object_thawer_load", G_ARRAY);

  if (count == 2)
    {
      // second value - perl objects
      {
        SV *sv = POPs;
        if (SvROK (sv))
          av = (AV *)SvREFCNT_inc (SvRV (sv));
      }

      // first value - text part, pad with 3 zeroes
      {
        SV *sv = POPs;
        STRLEN len;
        char *sv_ = SvPVbyte (sv, len);
        text = newSV (len + sizeof (thawer_eof));
        SvCUR_set (text, len + sizeof (thawer_eof));
        memcpy (SvPVX (text), sv_, len);
        memcpy (SvPVX (text) + len, thawer_eof, sizeof (thawer_eof));

        line = SvPVX (text);
        next ();
      }
    }

  CALL_END;
}

void
object_thawer::get (attachable *obj, int oid)
{
  if (!av || oid < 0) // this is actually an error of sorts
    return;

  SV **svp = av_fetch ((AV *)av, oid, 0);

  if (!svp || !SvROK (*svp))
    {
      LOG (llevError, "trying to thaw duplicate or never-issued oid %d, ignoring.\n", oid);
      return;
    }

  if (!SvROK (*svp))
    {
      LOG (llevError, "deserialised perl object is not an RV\n");
      return;
    }

  HV *hv = (HV *)SvRV (*svp);

  if (SvTYPE (hv) != SVt_PVHV)
    {
      LOG (llevError, "deserialised perl object is not a PVHV\n");
      return;
    }

  if (obj->self)
    {
      // the hard way(?)

      CALL_BEGIN (2);
      CALL_ARG_SV (newRV_inc ((SV *)obj->self));
      CALL_ARG_SV (newRV_inc ((SV *)hv));
      PUTBACK;
      call_method ("thawer_merge", G_DISCARD | G_EVAL);
      SPAGAIN;
      CALL_END;
    }
  else
    {
      // the easy way(?)

      obj->self = hv;
      SvRV_set (*svp, &PL_sv_undef);

      sv_magicext ((SV *)obj->self, 0, PERL_MAGIC_ext, &attachable::vtbl, (char *)obj, 0);
    }

  obj->reattach ();
}

object_thawer::~object_thawer ()
{
  if (text) SvREFCNT_dec (text);
  if (av)   SvREFCNT_dec (av);

  resolve_delayed_derefs (false);

  free ((void *)name);
}

static void
error_out ()
{
  if (object_thawer::errors_are_fatal)
    {
      LOG (llevError, "(parse errors at this time are fatal, exiting)");
      exit (1);
    }
}

void
object_thawer::parse_warn (const char *msg) const
{
  LOG (llevWarn, "%s:%d, \"%s %s\": %s\n",
       this->name, linenum,
       kw_str ? kw_str : "<null>",
       value  ? value  : "<null>",
       msg);
}

bool
object_thawer::parse_error (const char *type, const char *name, bool skip) const
{
  if (!type) type = "file section";
  if (!name) name = "generic";

  switch (kw)
    {
      case KW_EOF:
        LOG (llevError, "%s:%d end of file while reading %s '%s', aborting load.\n",
             this->name, linenum, type, name);
        error_out ();
        return false;

      case KW_ERROR:
        LOG (llevError, "%s:%d error while reading %s '%s', at '%s', aborting load.\n",
             this->name, linenum,
             type, name,
             kw_str ? kw_str : "<file load>");
        error_out ();
        return false;

      default:
        LOG (llevError, "%s:%d unexpected line (%s %s) while reading %s '%s', %s.\n",
             this->name, linenum,
             kw_str ? kw_str : "<null>",
             value  ? value  : "<null>",
             type, name,
             skip ? "skipping line" : "aborting load");
        error_out ();
        return skip;
    }
}

void
object_thawer::next ()
{
  if (!line)
    {
      kw = KW_ERROR;
      return;
    }

  for (;;)
    {
      char *p = line;

      if (expect_false (*p <= ' '))
        {
          // skip whitespace (only some files need this)
          while (*p == ' ' || *p == '\t')
            p++;

          line = p;
        }

      if (!*p)
        {
          kw = KW_EOF;
          break;
        }

      // parse keyword
      while (*p > ' ')
        p++;

      int klen = p - line;

      value_nn = "";
      value = 0;

      if (*p++ != '\n')
        {
          // parse value
          while (*(unsigned char *)p <= ' ' && *p != '\n')
            ++p;

          value_nn = value = p;

          while (*p != '\n')
            p++;

          *p++ = 0;
        }

      ++linenum;
      line [klen] = 0;
      keyword_idx *kw_idx = kw_lex::match (line, klen);

      kw_str = line;
      line = p;

      if (kw_idx)
        {
          kw = kw_idx->index;
          break;
        }
      else if (!*kw_str || *kw_str == '#')
        ; // empty/comment line
      else
        {
          kw = KW_ERROR;
          break;
        }
    }
}

bool
object_thawer::next_line ()
{
  if (!line)
    {
      kw = KW_ERROR;
      return 0;
    }

  for (;;)
    {
      char *p = line;

      if (expect_false (*p <= ' '))
        {
          // skip whitespace (only some files need this)
          while (*p == ' ' || *p == '\t')
            p++;

          line = p;
        }

      if (!*p)
        {
          kw = KW_EOF;
          return 0;
        }

      kw       = KW_value;
      kw_str   = p;
      value_nn = p;
      value    = p;

      // parse till newline
      while (*p > '\n')
        p++;

      if (*p == '\n')
        *p++ = 0;

      ++linenum;

      line = p;

      if (*kw_str && *kw_str != '#')
        break;

      // empty/comment line -> skip it
    }

  return 1;
}

void
object_thawer::skip ()
{
  shstr ml;

  switch (kw)
    {
      case KW_msg:     get_ml (KW_endmsg    , ml); break;
      case KW_lore:    get_ml (KW_endlore   , ml); break;
      case KW_maplore: get_ml (KW_endmaplore, ml); break;
      default:                                     break;
    }

  next ();
}
 
void
object_thawer::skip_block ()
{
  // must not stop at KW_ERROR, as those signify custom keys
  while (kw != KW_EOF)
    {
      keyword w = kw;
      skip ();

      if (0 && (w == KW_map || w == KW_arch || w == KW_object || w == KW_region))
        skip_block ();
      else if (w == KW_end)
        break;
    }
}

void
object_thawer::get_ml (keyword kend, shstr &sh)
{
  char kw[128];

  int klen = keyword_len [kend];

  kw [0] = '\n';
  memcpy (kw + 1, keyword_str [kend], klen);
  kw [klen + 1] = '\n';
  kw [klen + 2] = 0;

  ++linenum;

  // first test for completely empty msg... "endXXX\n"
  if (!strncmp (line, kw + 1, klen + 1))
    {
      sh = 0;

      line += klen + 1;

      return;
    }
  else
    {
      // multi-line strings are delimited by "\nendXXX\n" or "endXXX\n" (NULL)

      char *end = strstr (line, kw);

      if (!end)
        {
          sh = 0;
          return;
        }

      *end = 0;
      sh = line;

      // count line numbers
      while (line < end)
        linenum += *line++ == '\n';

      line += keyword_len [kend];

      while (*line++ != '\n')
        ;

      ++linenum;
    }
}

sint32
object_thawer::get_sint32 () const
{
  const char *p = value_nn;

  sint32 val = 0;
  bool negate;

  if (*p == '-')
    {
      negate = true;
      ++p;
    }
  else
    negate = false;

  do
    {
      val *= 10;
      val += *p++ - '0';
    }
  while (*p);

  return negate ? -val : val;
}

void
object_thawer::delayed_deref (attachable *op, object_ptr &ptr, const char *ref)
{
  op->refcnt_inc ();
  delayed_ref r = { op, &ptr, ref ? strdup (ref) : 0 };
  delrefs.push_back (r);
  ptr = 0;
}

void
object_thawer::resolve_delayed_derefs (bool deref)
{
  while (!delrefs.empty ())
    {
      delayed_ref r = delrefs.back ();
      delrefs.pop_back ();

      if (deref)
        *r.ptr = object::deref (r.ref);

      free ((void *)r.ref);
      r.op->refcnt_dec ();
    }
}