/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008,2009,2010 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * Copyright (©) 2001 Mark Wedel & Crossfire Development Team
 * Copyright (©) 1992 Frank Tore Johansen
 * 
 * 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 <time.h>
#include <stdio.h>
#include <global.h>
#include <random_map.h>
#include <rproto.h>
#include <sproto.h>

#define CEDE coroapi::cede_to_tick ()

static void symmetrize_layout (Layout maze, random_map_params *RP);
static void rotate_layout (Layout maze, int rotation);

noinline SV *
random_map_params::get_sv (const char *option) const
{
  SV **he = hv_fetch (hv, option, strlen (option), 0);

  return he ? *he : 0;
}

noinline const_utf8_string
random_map_params::get_str (const char *option, const_utf8_string fallback) const
{
  SV *sv = get_sv (option);
  return sv ? cfSvPVutf8_nolen (sv) : fallback;
}

noinline IV
random_map_params::get_iv (const char *option, IV fallback) const
{
  SV *sv = get_sv (option);
  return sv ? SvIV (sv) : fallback;
}

noinline UV
random_map_params::get_uv (const char *option, UV fallback) const
{
  SV *sv = get_sv (option);
  return sv ? SvUV (sv) : fallback;
}

noinline NV
random_map_params::get_nv (const char *option, NV fallback) const
{
  SV *sv = get_sv (option);
  return sv ? SvNV (sv) : fallback;
}

noinline void
random_map_params::set (const char *option, SV *value) const
{
  int len = strlen (option);

  if (value)
    hv_store  (hv, option, len, value, 0);
  else
    hv_delete (hv, option, len, G_DISCARD);
}

noinline void
random_map_params::set (const char *option, const_utf8_string value) const
{
  set (option, value && *value ? newSVpvn_utf8 (value, strlen (value), 1) : 0);
}

void
random_map_params::set (const char *option, IV value) const
{
  set (option, newSViv (value));
}

void
random_map_params::set (const char *option, UV value) const
{
  set (option, newSVuv (value));
}

void
random_map_params::set (const char *option, NV value) const
{
  set (option, newSVnv (value));
}

void
random_map_params::hv_clone ()
{
  HV *copy = newHV ();

  hv_iterinit (hv);

  // does not work for utf-8 keys
  while (HE *he = hv_iternext (hv))
    {
      STRLEN klen; const char *key = HePV (he, klen);
      hv_store (copy, key, klen, newSVsv (HeVAL (he)), HeHASH (he));
    }

  SvREFCNT_dec (hv);
  hv = copy;
}

shstr_tmp
random_map_params::as_shstr () const
{
  set ("xsize"              , xsize);
  set ("ysize"              , ysize);
  set ("monsterstyle"       , monsterstyle);
  set ("exit_on_final_map"  , exit_on_final_map);
  set ("layoutstyle"        , layoutstyle);
  set ("doorstyle"          , doorstyle);
  set ("final_map"          , final_map);
  set ("this_map"           , this_map);
  set ("expand2x"           , expand2x);
  set ("layoutoptions1"     , layoutoptions1);
  set ("layoutoptions2"     , layoutoptions2);
  set ("layoutoptions3"     , layoutoptions3);
  set ("symmetry"           , symmetry);
  set ("dungeon_depth"      , dungeon_depth);
  set ("orientation"        , orientation);
  set ("origin_x"           , origin_x);
  set ("origin_y"           , origin_y);
  set ("random_seed"        , (UV)random_seed);
  set ("difficulty"         , difficulty && difficulty_given ? difficulty : 0);
  set ("difficulty_increase", difficulty_increase);
  set ("dungeon_level"      , dungeon_level);

  dynbuf_text buf;
  hv_iterinit (hv);

  // does not work for utf-8 keys
  while (HE *he = hv_iternext (hv))
    {
      STRLEN klen; const char *key   = HePV (he, klen);
      STRLEN vlen; const char *value = SvPVutf8 (HeVAL (he), vlen);

      buf.fadd (key, klen);
      buf << ' ';
      buf.fadd (value, vlen);
      buf << '\n';
    }

  return shstr (buf);
}

random_map_params::~random_map_params ()
{
  SvREFCNT_dec (hv);
}

/* takes a map and makes it symmetric: adjusts Xsize and
 * Ysize to produce a symmetric map.
 */
static void
symmetrize_layout (Layout layout, random_map_params *RP)
{
  if (RP->symmetry_used == SYMMETRY_NONE)
    return;

  Layout sym_layout (
    RP->symmetry_used == SYMMETRY_X || RP->symmetry_used == SYMMETRY_XY ? layout->w * 2 - 3 : layout->w,
    RP->symmetry_used == SYMMETRY_Y || RP->symmetry_used == SYMMETRY_XY ? layout->h * 2 - 3 : layout->h
  );

  if (RP->symmetry_used == SYMMETRY_X)
    for (int i = 0; i < sym_layout->w / 2 + 1; i++)
      for (int j = 0; j < sym_layout->h; j++)
        {
          sym_layout[i                  ][j] =
          sym_layout[sym_layout->w - i - 1][j] = layout[i][j];
        }

  if (RP->symmetry_used == SYMMETRY_Y)
    for (int i = 0; i < sym_layout->w; i++)
      for (int j = 0; j < sym_layout->h / 2 + 1; j++)
        {
          sym_layout[i][j                  ] =
          sym_layout[i][sym_layout->h - j - 1] = layout[i][j];
        }

  if (RP->symmetry_used == SYMMETRY_XY)
    for (int i = 0; i < sym_layout->w / 2 + 1; i++)
      for (int j = 0; j < sym_layout->h / 2 + 1; j++)
        {
          sym_layout[i                  ][j                  ] =
          sym_layout[i                  ][sym_layout->h - j - 1] =
          sym_layout[sym_layout->w - i - 1][j                  ] =
          sym_layout[sym_layout->w - i - 1][sym_layout->h - j - 1] = layout[i][j];
        }

  layout.swap (sym_layout);
  sym_layout.free ();

  /* reconnect disjointed spirals */
  /* reconnect disjointed nethacklayouts:  the routine for
     spirals will do the trick? */
  if (RP->map_layout_style == LAYOUT_SPIRAL
      || RP->map_layout_style == LAYOUT_ROGUELIKE)
    connect_spirals (layout->w, layout->h, RP->symmetry_used, layout);
}

/*  takes  a map and rotates it.  This completes the
    onion layouts, making them possibly centered on any wall. 
    It'll modify Xsize and Ysize if they're swapped.
*/
static void
rotate_layout (Layout layout, int rotation)
{
  int w = layout->w;
  int h = layout->h;

  switch (rotation)
    {
      case 2:                  /* a reflection */
        {
          Layout new_layout (w, h);

          for (int i = 0; i < w; i++)                   /* copy a reflection back */
            for (int j = 0; j < h; j++)
              new_layout[i][j] = layout[w - i - 1][h - j - 1];

          layout.swap (new_layout);
          new_layout.free ();
        }
        break;

      case 1:
      case 3:
        {
          Layout new_layout (h, w);

          if (rotation == 1)    /* swap x and y */
            for (int i = 0; i < w; i++)
              for (int j = 0; j < h; j++)
                new_layout[j][i] = layout[i][j];

          if (rotation == 3) /* swap x and y */
            for (int i = 0; i < w; i++)
              for (int j = 0; j < h; j++)
                new_layout[j][i] = layout[w - i - 1][h - j - 1];

          layout.swap (new_layout);
          new_layout.free ();
        }
        break;
    }
}

/*  checks the layout to see if I can stick a horizontal(dir = 0) wall
    (or vertical, dir == 1)
    here which ends up on other walls sensibly.  */
static int
can_make_wall (char **maze, int dx, int dy, int dir, random_map_params *RP)
{
  int i1;
  int length = 0;

  /* dont make walls if we're on the edge. */
  if (dx == 0 || dx == (RP->Xsize - 1) || dy == 0 || dy == (RP->Ysize - 1))
    return -1;

  /* don't make walls if we're ON a wall. */
  if (maze[dx][dy] != 0)
    return -1;

  if (dir == 0)                 /* horizontal */
    {
      int y = dy;

      for (i1 = dx - 1; i1 > 0; i1--)
        {
          int sindex = surround_flag2 (maze, i1, y, RP);

          if (sindex == 1)
            break;
          if (sindex != 0)
            return -1;          /* can't make horiz.  wall here */
          if (maze[i1][y] != 0)
            return -1;          /* can't make horiz.  wall here */
          length++;
        }

      for (i1 = dx + 1; i1 < RP->Xsize - 1; i1++)
        {
          int sindex = surround_flag2 (maze, i1, y, RP);

          if (sindex == 2)
            break;
          if (sindex != 0)
            return -1;          /* can't make horiz.  wall here */
          if (maze[i1][y] != 0)
            return -1;          /* can't make horiz.  wall here */
          length++;
        }
      return length;
    }
  else
    {                           /* vertical */
      int x = dx;

      for (i1 = dy - 1; i1 > 0; i1--)
        {
          int sindex = surround_flag2 (maze, x, i1, RP);

          if (sindex == 4)
            break;
          if (sindex != 0)
            return -1;          /* can't make vert. wall here */
          if (maze[x][i1] != 0)
            return -1;          /* can't make horiz.  wall here */
          length++;
        }

      for (i1 = dy + 1; i1 < RP->Ysize - 1; i1++)
        {
          int sindex = surround_flag2 (maze, x, i1, RP);

          if (sindex == 8)
            break;
          if (sindex != 0)
            return -1;          /* can't make verti. wall here */
          if (maze[x][i1] != 0)
            return -1;          /* can't make horiz.  wall here */
          length++;
        }

      return length;
    }

  return -1;
}

/*  take a layout and make some rooms in it. 
    --works best on onions.*/
static void
roomify_layout (char **maze, random_map_params *RP)
{
  int tries = RP->Xsize * RP->Ysize / 30;

  for (int ti = 0; ti < tries; ti++)
    {
      /* starting location for looking at creating a door */
      int dx = rmg_rndm (RP->Xsize);
      int dy = rmg_rndm (RP->Ysize);

      /* results of checking on creating walls. */
      int cx = can_make_wall (maze, dx, dy, 0, RP); /* horizontal */
      int cy = can_make_wall (maze, dx, dy, 1, RP); /* vertical */

      if (cx == -1)
        {
          if (cy != -1)
            make_wall (maze, dx, dy, 1);

          continue;
        }

      if (cy == -1)
        {
          make_wall (maze, dx, dy, 0);
          continue;
        }

      if (cx < cy)
        make_wall (maze, dx, dy, 0);
      else
        make_wall (maze, dx, dy, 1);
    }
}

int
make_wall (char **maze, int x, int y, int dir)
{
  maze[x][y] = 'D';             /* mark a door */

  switch (dir)
    {
      case 0:                  /* horizontal */
        {
          for (int i1 = x - 1; maze[i1][y] == 0; --i1) maze[i1][y] = '#';
          for (int i1 = x + 1; maze[i1][y] == 0; ++i1) maze[i1][y] = '#';
          break;
        }
      case 1:                  /* vertical */
        {
          for (int i1 = y - 1; maze[x][i1] == 0; --i1) maze[x][i1] = '#';
          for (int i1 = y + 1; maze[x][i1] == 0; ++i1) maze[x][i1] = '#';
          break;
        }
    }

  return 0;
}

/*  puts doors at appropriate locations in a layout. */
static void
doorify_layout (char **maze, random_map_params *RP)
{
  int ndoors = RP->Xsize * RP->Ysize / 60;      /* reasonable number of doors. */
  int doorlocs = 0;             /* # of available doorlocations */

  uint16 *doorlist_x = salloc<uint16> (RP->Xsize * RP->Ysize);
  uint16 *doorlist_y = salloc<uint16> (RP->Xsize * RP->Ysize);

  /* make a list of possible door locations */
  for (int i = 1; i < RP->Xsize - 1; i++)
    for (int j = 1; j < RP->Ysize - 1; j++)
      {
        int sindex = surround_flag (maze, i, j, RP);

        if (sindex == 3 || sindex == 12)        /* these are possible door sindex */
          {
            doorlist_x[doorlocs] = i;
            doorlist_y[doorlocs] = j;
            doorlocs++;
          }
      }

  while (ndoors > 0 && doorlocs > 0)
    {
      int di = rmg_rndm (doorlocs);
      int i = doorlist_x[di];
      int j = doorlist_y[di];
      int sindex = surround_flag (maze, i, j, RP);

      if (sindex == 3 || sindex == 12)  /* these are possible door sindex */
        {
          maze[i][j] = 'D';
          ndoors--;
        }

      /* reduce the size of the list */
      doorlocs--;
      doorlist_x[di] = doorlist_x[doorlocs];
      doorlist_y[di] = doorlist_y[doorlocs];
    }

  sfree (doorlist_x, RP->Xsize * RP->Ysize);
  sfree (doorlist_y, RP->Xsize * RP->Ysize);
}

/*  function selects the layout function and gives it whatever
    arguments it needs.  */
static Layout
layoutgen (random_map_params *RP)
{
  Layout layout (RP);

  switch (RP->map_layout_style)
    {
      case LAYOUT_ONION:
        map_gen_onion (layout, RP->layoutoptions1, RP->layoutoptions2);

        if (!(rmg_rndm (3)) && !(RP->layoutoptions1 & (RMOPT_WALLS_ONLY | RMOPT_WALL_OFF)))
          roomify_layout (layout, RP);

        break;

      case LAYOUT_MAZE:
        maze_gen (layout, RP->get_iv ("maze_type", rmg_rndm (4)));

        if (!(rmg_rndm (2)))
          doorify_layout (layout, RP);

        break;

      case LAYOUT_SPIRAL:
        map_gen_spiral (layout, RP->layoutoptions1);

        if (!(rmg_rndm (2)))
          doorify_layout (layout, RP);

        break;

      case LAYOUT_ROGUELIKE:
        /* Don't put symmetry in rogue maps.  There isn't much reason to
         * do so in the first place (doesn't make it any more interesting),
         * but more importantly, the symmetry code presumes we are symmetrizing
         * spirals, or maps with lots of passages - making a symmetric rogue
         * map fails because its likely that the passages the symmetry process
         * creates may not connect the rooms.
         */
        RP->symmetry_used = SYMMETRY_NONE;
        roguelike_layout_gen (layout, RP->layoutoptions1);
        /* no doorifying...  done already */
        break;

      case LAYOUT_SNAKE:
        make_snake_layout (layout, RP->layoutoptions1);

        if (rmg_rndm (2))
          roomify_layout (layout, RP);

        break;

      case LAYOUT_SQUARE_SPIRAL:
        make_square_spiral_layout (layout, RP->layoutoptions1);

        if (rmg_rndm (2))
          roomify_layout (layout, RP);

        break;

      case LAYOUT_CAVE:
        layout->gen_cave (RP->get_iv ("cave_type", rmg_rndm (4)));

        if (!(rmg_rndm (2)))
          doorify_layout (layout, RP);

        break;

      default:
        abort ();
    }

  /*  rotate the layout randomly */
  rotate_layout (layout, rmg_rndm (4));

  symmetrize_layout (layout, RP);

#ifdef RMAP_DEBUG
  dump_layout (layout);
#endif

  if (RP->expand2x)
    expand2x (layout);

  return layout;
}

bool
maptile::generate_random_map (random_map_params *RP)
{
  RP->Xsize = RP->xsize;
  RP->Ysize = RP->ysize;

  /* pick a random seed, or use the one from the input file */
  RP->random_seed = RP->random_seed
                       ? RP->random_seed + RP->dungeon_level
                       : time (0);

  // we run "single-threaded"
  rmg_rndm.seed (RP->random_seed);

  shstr buf = RP->as_shstr ();

  if (RP->difficulty == 0)
    {
      RP->difficulty = RP->dungeon_level;       /* use this instead of a map difficulty  */

      if (RP->difficulty_increase > 0.001)
        RP->difficulty = (int) ((float) RP->dungeon_level * RP->difficulty_increase);

      if (RP->difficulty < 1)
        RP->difficulty = 1;
    }
  else
    RP->difficulty_given = 1;

  if (RP->Xsize < MIN_RANDOM_MAP_SIZE)
    RP->Xsize = MIN_RANDOM_MAP_SIZE + rmg_rndm (25) + 5;

  if (RP->Ysize < MIN_RANDOM_MAP_SIZE)
    RP->Ysize = MIN_RANDOM_MAP_SIZE + rmg_rndm (25) + 5;

  if (RP->symmetry == SYMMETRY_RANDOM)
    RP->symmetry_used = rmg_rndm (SYMMETRY_XY) + 1;
  else
    RP->symmetry_used = RP->symmetry;

  if (RP->symmetry_used == SYMMETRY_Y || RP->symmetry_used == SYMMETRY_XY)
    RP->Ysize = RP->Ysize / 2 + 1;

  if (RP->symmetry_used == SYMMETRY_X || RP->symmetry_used == SYMMETRY_XY)
    RP->Xsize = RP->Xsize / 2 + 1;

  if (RP->expand2x > 0)
    {
      RP->Xsize /= 2;
      RP->Ysize /= 2;
    }

  RP->map_layout_style = LAYOUT_NONE;

  /* Redo this - there was a lot of redundant code of checking for preset
   * layout style and then random layout style.  Instead, figure out
   * the numeric layoutstyle, so there is only one area that actually
   * calls the code to make the maps.
   */
  if (strstr (RP->layoutstyle, "onion"))
    RP->map_layout_style = LAYOUT_ONION;
  else if (strstr (RP->layoutstyle, "maze"))
    RP->map_layout_style = LAYOUT_MAZE;
  else if (strstr (RP->layoutstyle, "spiral"))
    RP->map_layout_style = LAYOUT_SPIRAL;
  else if (strstr (RP->layoutstyle, "rogue"))
    RP->map_layout_style = LAYOUT_ROGUELIKE;
  else if (strstr (RP->layoutstyle, "snake"))
    RP->map_layout_style = LAYOUT_SNAKE;
  else if (strstr (RP->layoutstyle, "squarespiral"))
    RP->map_layout_style = LAYOUT_SQUARE_SPIRAL;
  else if (strstr (RP->layoutstyle, "cave"))
    RP->map_layout_style = LAYOUT_CAVE;
  else if (RP->map_layout_style == LAYOUT_NONE)
    RP->map_layout_style = rmg_rndm (NROFLAYOUTS - 1) + 1; /* No style found - choose one randomly */
  else
    abort ();

  Layout layout = layoutgen (RP);

#ifdef RMAP_DEBUG
  dump_layout (layout);
#endif

  /* increment these for the current map */
  ++RP->dungeon_level;

  // need to patch RP becasue following code doesn't use the Layout object
  RP->Xsize = layout->w;
  RP->Ysize = layout->h;

  /* allocate the map and set the floor */
  make_map_floor (layout, RP->get_str ("floorstyle", ""), RP);

  /* set region */
  default_region = RP->region;

  CEDE;

  place_specials_in_map (this, layout, RP);

  CEDE;

  const char *wallstyle = RP->get_str ("wallstyle", 0);

  /* create walls unless the wallstyle is "none" */
  if (strcmp (wallstyle, "none"))
    {
      make_map_walls (this, layout, wallstyle, RP->get_str ("miningstyle", ""), RP);

      /* place doors unless doorstyle or wallstyle is "none" */
      if (strcmp (RP->doorstyle, "none"))
        put_doors (this, layout, RP->doorstyle, RP);
    }

  CEDE;

  const char *exitstyle = RP->get_str ("exitstyle", "");

  /* create exits unless the exitstyle is "none" */
  if (strcmp (exitstyle, "none"))
    place_exits (this, layout, exitstyle, RP->orientation, RP);

  CEDE;

  /* create monsters unless the monsterstyle is "none" */
  if (strcmp (RP->monsterstyle, "none"))
    place_monsters (this, RP->monsterstyle, RP->difficulty, RP);

  CEDE;

  /* treasures needs to have a proper difficulty set for the map. */
  difficulty = estimate_difficulty ();

  CEDE;

  const char *treasurestyle = RP->get_str ("treasurestyle", "");

  /* create treasure unless the treasurestyle is "none" */
  place_treasure (this, layout, treasurestyle, RP->get_iv ("treasureoptions"), RP);

  CEDE;

  const char *decorstyle = RP->get_str ("treasurestyle", "");

  /* create decor unless the decorstyle is "none" */
  if (strcmp (decorstyle, "none"))
    put_decor (this, layout, decorstyle, RP->get_iv ("decoroptions"), RP);

  CEDE;

  /* generate treasures, etc. */
  fix_auto_apply ();

  CEDE;

  unblock_exits (this, layout, RP);

  msg = buf;
  in_memory = MAP_ACTIVE;

  CEDE;

  return 1;
}