/* omega copyright (c) 1987,1988,1989 by Laurence Raphael Brothers */
/* gen1.c */
/* level generator functions */

#include "glob.h"

#include <time.h>

/* Deallocate current dungeon */
void free_dungeon(void)
{
#ifndef SAVE_LEVELS
  plv tlv;
  
  while (Dungeon != NULL) {
    tlv = Dungeon;
    Dungeon = Dungeon->next;
    free_level(tlv);
  }
#else
  if (Dungeon != NULL)
  {
    sprintf(Str2,"om%d*.lev",Dungeon->environment);
    kill_levels(Str2);
  }
#endif
}


/* erase the level w/o deallocating it*/
void clear_level(struct level *dungeon_level)
{
  int i,j;
  if (dungeon_level != NULL) {
    dungeon_level->generated = FALSE;
    dungeon_level->numrooms = 0;
    dungeon_level->level_length = 0;
    dungeon_level->level_width = 0;
    dungeon_level->tunnelled = 0;
    dungeon_level->depth = 0;
    dungeon_level->mlist = NULL;
    dungeon_level->next = NULL;
    dungeon_level->last_visited = time(NULL);
    for(i=0;i<MAXWIDTH;i++)
      for(j=0;j<MAXLENGTH;j++) {
	dungeon_level->site[i][j].locchar = WALL;
	dungeon_level->site[i][j].showchar = SPACE;
	dungeon_level->site[i][j].creature = NULL;
	dungeon_level->site[i][j].things = NULL;
	/* PGM: clear_level is called from restore_level, before it knows anything about the current environment, which is where difficulty() gets its information! */
	dungeon_level->site[i][j].aux = difficulty()*20;
	dungeon_level->site[i][j].buildaux = 0;
	dungeon_level->site[i][j].p_locf = L_NO_OP;
	dungeon_level->site[i][j].lstatus = 0;
	dungeon_level->site[i][j].roomnumber = RS_WALLSPACE;
      }
  }
}



/* Looks for level tolevel in current dungeon which is named by
Dungeon, which may be NULL. If the level is found, and rewrite_level
is FALSE, and the level has already been generated, nothing happens
beyond Level being set correctly. Otherwise the level is recreated
from scratch */

void change_level (char fromlevel, char tolevel, char rewrite_level)
{
  struct level * thislevel = NULL;
  Player.sx = -1;
  Player.sy = -1; /* sanctuary effect dispelled */

#ifndef SAVE_LEVELS
  thislevel = findlevel(Dungeon, tolevel);
  deepest[Current_Environment] = max(deepest[Current_Environment], tolevel);
  if (!thislevel)
    {
      thislevel = checkmalloc(sizeof(levtype));
      clear_level(thislevel);
      Level = thislevel;
      Level->next = Dungeon;
      Dungeon = Level;
    }
#else
  thislevel = msdos_changelevel(Level, Current_Environment, tolevel);
  deepest[Current_Environment] = max(deepest[Current_Environment], tolevel);
  if (!thislevel)
    {
      thislevel = &TheLevel;
      clear_level(thislevel);
      Level = thislevel;
      Level->next = Dungeon;
      Dungeon = Level;
    }
#endif

  Level = thislevel;
  if ((!Level->generated) || rewrite_level)
    {
      initrand(Current_Environment, tolevel);
      Level->environment = Current_Environment;
      Level->depth = tolevel;
      Level->generated = TRUE;

      switch (Current_Environment)
        {
        case E_CAVES: 
          Level->level_width = CAVES_WIDTH;
          Level->level_length = CAVES_LENGTH;
          if ((0 == random_range(4)) && (tolevel < MaxDungeonLevels))
            room_level();
          else
            cavern_level();
          break;

        case E_SEWERS: 
          Level->level_width = SEWERS_WIDTH;
          Level->level_length = SEWERS_LENGTH;
          if ((0 == random_range(4)) && (tolevel < MaxDungeonLevels))
            room_level();
          else
            sewer_level(); 
          break;

        case E_CASTLE:
          Level->level_width = CASTLE_WIDTH;
          Level->level_length = CASTLE_LENGTH;
          room_level();
          break;

        case E_PALACE: /* PGM TODO */
          Level->level_width = PALACE_WIDTH;
          Level->level_length = PALACE_LENGTH;
          room_level();
          break;

        case E_ASTRAL:
          Level->level_width = ASTRAL_WIDTH;
          Level->level_length = ASTRAL_LENGTH;
          maze_level();
          break;

        case E_VOLCANO:
          Level->level_width = VOLCANO_WIDTH;
          Level->level_length = VOLCANO_LENGTH;
          switch (random_range(3))
            {
            case 0: cavern_level(); break;
            case 1: room_level(); break;
            case 2: maze_level(); break;
            }
          break;

        default:
          print3("This dungeon not implemented!");
          assert(FALSE);
          break;
        }

      install_traps();
      install_specials();
      make_stairs(fromlevel);
      make_stairs(fromlevel);
      initrand(E_RESTORE, 0);
      populate_level(Current_Environment);
      stock_level();
    }

  find_stairs(fromlevel, tolevel);
  ScreenOffset = Player.y - (ScreenLength/2);
  show_screen();
  screencheck(Player.x,Player.y);
  drawvision(Player.x,Player.y);

  /* synchronize with player on level change */
  Player.click = (Tick+1)%60;
  roomcheck();
}

#ifndef SAVE_LEVELS
/* tries to find the level of depth levelnum in dungeon; if can't find
   it returns NULL */
plv findlevel(struct level *dungeon, char levelnum)
{
  if (dungeon == NULL) return(NULL);
  else {
    while((dungeon->next != NULL) && (dungeon->depth != levelnum))
      dungeon = dungeon->next;
    if (dungeon->depth == levelnum) {
      dungeon->last_visited = time(NULL);
      return(dungeon);
    }
    else return(NULL);
  }
}
#endif



/* keep going in one orthogonal direction or another until we hit our */
/* destination */

void straggle_corridor(int fx, int fy, int tx, int ty, Symbol loc, char rsi)
{
  int dx,dy;
  while ((fx != tx) || (fy != ty)) {
    dx = tx - fx;
    dy = ty - fy;
    if (random_range(abs(dx)+abs(dy)) < abs(dx))
      corridor_crawl(&fx,&fy,sign(dx),0,random_range(abs(dx))+1,loc,rsi);
    else corridor_crawl(&fx,&fy,0,sign(dy),random_range(abs(dy))+1,loc,rsi);
  }
}


void makedoor(int x, int y)
{
  if (random_range(20) <= Level->depth/10) {
    Level->site[x][y].locchar = FLOOR;
    lset(x,y,SECRET);
  }
  else if (random_range(20)<=Level->depth/2) {
    Level->site[x][y].locchar = CLOSED_DOOR;
    if (random_range(20) <= Level->depth/10) 
      lset(x,y,SECRET);
    if (random_range(40) <= Level->depth) 
      Level->site[x][y].aux = LOCKED;
    else Level->site[x][y].aux = UNLOCKED;
  }
  else {
    Level->site[x][y].locchar = OPEN_DOOR;
    Level->site[x][y].aux = UNLOCKED;
  }
  if (! loc_statusp(x,y,SECRET)) {
    lset(x,y+1,STOPS);
    lset(x+1,y,STOPS);
    lset(x-1,y,STOPS);
    lset(x,y-1,STOPS);
    lset(x,y,STOPS);
  }
  Level->site[x][y].p_locf = L_NO_OP; 
  /* prevents water corridors from being instant death in sewers */
}


void corridor_crawl(int *fx, int *fy, int sx, int sy, int n, 
                    Symbol loc, char rsi)
{
  int i;
  for (i=0;i<n;i++) {
    *fx += sx;
    *fy += sy;
    if ((*fx < Level->level_width) && 
	(*fx > -1) && 
	(*fy > -1) && 
	(*fy < Level->level_length)) {
      Level->site[*fx][*fy].locchar = loc;
      if (Level->site[*fx][*fy].roomnumber == RS_WALLSPACE)
	Level->site[*fx][*fy].roomnumber = rsi;
      if (loc==WATER) 
	Level->site[*fx][*fy].p_locf = L_WATER;
      else if (loc==FLOOR) 
	Level->site[*fx][*fy].p_locf = L_NO_OP;
      else if (loc==RUBBLE)
	Level->site[*fx][*fy].p_locf = L_RUBBLE;
    }
  }
}  


char *roomname(int index)
{
  switch(index) {
  case RS_ZORCH:strcpy(Str4,"A place zorched by powerful magic.");break;
  case RS_COURT:strcpy(Str4,"The Court of the ArchMage."); break;
  case RS_CIRCLE:strcpy(Str4,"The Astral Demesne of the Circle of Sorcerors");
    break;
  case RS_MAGIC_ISLE: strcpy(Str4,"An island positively reeking of magic");
    break;
  case RS_STARPEAK: strcpy(Str4,"Near the oddly glowing peak of a mountain");
    break;
  case RS_VOLCANO: strcpy(Str4,"Deep within the bowels of the earth"); break;
  case RS_HIGHASTRAL: strcpy(Str4,"The High Astral Plane"); break;
  case RS_EARTHPLANE: strcpy(Str4,"The Plane of Earth"); break;
  case RS_WATERPLANE: strcpy(Str4,"The Plane of Water"); break;
  case RS_FIREPLANE: strcpy(Str4,"The Plane of Fire"); break;
  case RS_AIRPLANE: strcpy(Str4,"The Plane of Air"); break;
  case RS_KITCHEN: strcpy(Str4,"A kitchen"); break;
  case RS_BATHROOM: strcpy(Str4,"A bathroom"); break;
  case RS_BEDROOM: strcpy(Str4,"A bedroom"); break;
  case RS_DININGROOM: strcpy(Str4,"A dining room"); break;
  case RS_SECRETPASSAGE: strcpy(Str4,"A secret passage"); break;
  case RS_CLOSET: strcpy(Str4,"A stuffy closet"); break;
  case RS_ARENA: strcpy(Str4,"The Rampart Arena"); break;
  case RS_DROWNED_SEWER: strcpy(Str4,"A water-filled sewer node"); break;
  case RS_DRAINED_SEWER: strcpy(Str4,"An unused sewer node"); break;
  case RS_SEWER_DUCT: strcpy(Str4,"A winding sewer duct"); break;
  case RS_DESTINY: strcpy(Str4,"The Halls of Fate"); break;
  case RS_DRUID: strcpy(Str4,"The Great Henge"); break;
  case RS_HECATE: strcpy(Str4,"The Church of the Far Side"); break;
  case RS_SET: strcpy(Str4,"The Temple of the Black Hand"); break;
  case RS_ATHENA: strcpy(Str4,"The Parthenon"); break;
  case RS_ODIN: strcpy(Str4,"The Shrine of the Noose"); break;
  case RS_ADEPT: strcpy(Str4,"The Adept's Challenge"); break;
  case RS_WYRM: strcpy(Str4,"The Sunken Cavern of the Great Wyrm."); break;
  case RS_OCEAN: strcpy(Str4,"The Underground Ocean."); break;
  case RS_PONDS: strcpy(Str4,"A series of subterranean pools and streams."); break;
  case RS_DRAGONLORD: strcpy(Str4,"The Lair of the DragonLord."); break;
  case RS_GOBLINKING: strcpy(Str4,"The Caves of the Goblins."); break;
  case RS_CAVERN: strcpy(Str4,"A vast natural cavern."); break;
  case RS_CORRIDOR: strcpy(Str4,"A dimly lit corridor."); break;
  case RS_WALLSPACE: strcpy(Str4,"A niche hollowed out of the wall."); break;
  /* following are above ROOMBASE */
  case RS_GARDEROBE: strcpy(Str4,"An abandoned garderobe."); break;
  case RS_CELL: strcpy(Str4,"A dungeon cell."); break;
  case RS_TILED: strcpy(Str4,"A tiled chamber."); break;
  case RS_CRYSTAL_CAVE: strcpy(Str4,"A crystal cavern."); break;
  case RS_BEDROOM2: strcpy(Str4,"Someone's bedroom."); break;
  case RS_STOREROOM: strcpy(Str4,"An old storeroom."); break;
  case RS_CHARRED: strcpy(Str4,"A room with charred walls."); break;
  case RS_MARBLE_HALL: strcpy(Str4,"A marble hall."); break;
  case RS_EERIE_CAVE: strcpy(Str4,"An eerie cave."); break;
  case RS_TREASURE: strcpy(Str4,"A ransacked treasure-chamber."); break;
  case RS_SMOKEY: strcpy(Str4,"A smoke-filled room."); break;
  case RS_APARTMENT: strcpy(Str4,"A well-appointed apartment."); break;
  case RS_ANTECHAMBER: strcpy(Str4,"An antechamber."); break;
  case RS_HAREM: strcpy(Str4,"An unoccupied harem."); break;
  case RS_MULTIPURPOSE: strcpy(Str4,"A multi-purpose room."); break;
  case RS_STALACTITES: strcpy(Str4,"A room filled with stalactites."); break;
  case RS_GREENHOUSE: strcpy(Str4,"An underground greenhouse."); break;
  case RS_WATERCLOSET: strcpy(Str4,"A water closet."); break;
  case RS_STUDY: strcpy(Str4,"A study."); break;
  case RS_LIVING_ROOM: strcpy(Str4,"A living room."); break;
  case RS_DEN: strcpy(Str4,"A comfortable den."); break;
  case RS_ABATOIR: strcpy(Str4,"An abatoir."); break;
  case RS_BOUDOIR: strcpy(Str4,"A boudoir.");break;
  case RS_STAR_CHAMBER: strcpy(Str4,"A star chamber.");break;
  case RS_MANMADE_CAVE: strcpy(Str4,"A manmade cavern."); break;
  case RS_SEWER_CONTROL: strcpy(Str4,"A sewer control room");break;
  case RS_SHRINE: strcpy(Str4,"A shrine to High Magic"); break;
  case RS_MAGIC_LAB: strcpy(Str4,"A magic laboratory"); break;
  case RS_PENTAGRAM: strcpy(Str4,"A room with inscribed pentagram");break;
  case RS_OMEGA_DAIS: strcpy(Str4,"A chamber with a blue crystal omega dais");
    break;
     /* WDT: removed period from description. */
  default: strcpy(Str4,"A room of mystery and allure"); break;
  }
  return(Str4);
}


/* puts the player on the first set of stairs from the apt level */
/* if can't find them, just drops player anywhere.... */
void find_stairs(char fromlevel, char tolevel)
{
  int i,j,found=FALSE;
  Symbol sitechar;
  if (fromlevel > tolevel) sitechar = STAIRS_DOWN; else sitechar = STAIRS_UP;
  for(i=0;i<Level->level_width;i++)
    for(j=0;j<Level->level_length;j++) 
      if ((Level->site[i][j].locchar == sitechar) && (! found)) { 
	found = TRUE;
	Player.x = i;
	Player.y = j;
	break;
      }
  if (! found) {
    findspace(&Player.x,&Player.y,-1);
    if (Level->environment != E_ASTRAL) {
      Level->site[Player.x][Player.y].locchar = sitechar;
      lset(Player.x, Player.y, CHANGED);
    }
  }
}



void install_traps(void)
{
  int i,j;
  for(i=0;i<Level->level_width;i++)
    for(j=0;j<Level->level_length;j++)
      if ((Level->site[i][j].locchar == FLOOR) &&
	  (Level->site[i][j].p_locf == L_NO_OP) &&
	  random_range(500) <= ((int)(Level->depth/6)))
	Level->site[i][j].p_locf = TRAP_BASE+random_range(NUMTRAPS);
}


/* x, y, is top left corner, l is length of side, rsi is room string index */
/* baux is so all rooms will have a key field. */
void build_square_room(int x, int y, int l, char rsi, int baux)
{
  int i,j;

  for(i=x;i<=x+l;i++)
    for(j=y;j<=y+l;j++){
      Level->site[i][j].roomnumber = rsi;
      Level->site[i][j].buildaux = baux;
    }
  for(i=x+1;i<x+l;i++)
    for(j=y+1;j<y+l;j++) {
      Level->site[i][j].locchar = FLOOR;
      Level->site[i][j].p_locf = L_NO_OP;
    }
}


void build_room(int x, int y, int l, char rsi, int baux)
{
  build_square_room(x,y,l,rsi,baux);
}

void cavern_level(void)
{
  int i,fx,fy,tx,ty,t,l,e;
  char rsi;

  Level->numrooms = 1;

  if ((Current_Dungeon == E_CAVES) && (Level->depth == CAVELEVELS))
    rsi = RS_GOBLINKING;
  else rsi = RS_CAVERN;
  t = random_range((Level->level_length)/2);
  l = random_range((Level->level_width)/2);
  e = random_range((Level->level_width)/8)+(Level->level_width)/8;
  build_square_room(t,l,e,rsi,0);
  
  for (i=0;i<16;i++) {
    findspace(&tx,&ty,-1);
    fx = random_range((Level->level_width)-2)+1;
    fy = random_range((Level->level_length)-2)+1;
    straggle_corridor(fx,fy,tx,ty,FLOOR,RS_CORRIDOR);
  }
  while (random_range(3)==1) {
    findspace(&tx,&ty,-1);
    fx = random_range((Level->level_width)-2)+1;
    fy = random_range((Level->level_length)-2)+1;
    straggle_corridor(fx,fy,tx,ty,WATER,RS_PONDS);
  }
  if (Current_Dungeon == E_CAVES) {
    if ((Level->depth == CAVELEVELS) && (! gamestatusp(COMPLETED_CAVES))) {
      findspace(&tx,&ty,-1);
      Level->mlist = ((pml) checkmalloc(sizeof(mltype)));
      Level->mlist->next = NULL;
      Level->mlist->m = 
	Level->site[tx][ty].creature = 
	  ((pmt) make_creature(GOBLIN_KING)); /* goblin king */
      Level->mlist->m->x = tx;
      Level->mlist->m->y = ty;
    }
  }
  else if (Current_Environment == E_VOLCANO) {
    if (Level->depth == VOLCANOLEVELS) {
      findspace(&tx,&ty,-1);
      Level->mlist = ((pml) checkmalloc(sizeof(mltype)));
      Level->mlist->next = NULL;
      Level->mlist->m = 
	Level->site[tx][ty].creature = 
	  ((pmt) make_creature(DEMON_EMP)); /* The demon emp */
      Level->mlist->m->x = tx;
      Level->mlist->m->y = ty;
    }
  }
}


void sewer_level(void)
{
  int i,tx,ty,t,l,e;
  char rsi;
  Symbol lchar;

  Level->numrooms = random_range(3)+3;
  rsi = RS_DRAINED_SEWER;
  for (i=0;i<Level->numrooms;i++) {
    do {
      t = random_range((Level->level_length)-10)+1;
      l = random_range((Level->level_width)-10)+1;
      e = 4;
    } while ((Level->site[l][t].roomnumber == rsi) ||
	     (Level->site[l+e][t].roomnumber == rsi) ||
	     (Level->site[l][t+e].roomnumber == rsi) ||
	     (Level->site[l+e][t+e].roomnumber == rsi));
    if (random_range(5)) {
      lchar = FLOOR;
      rsi = RS_DRAINED_SEWER;
    }
    else {
      lchar = WATER;
      rsi = RS_DROWNED_SEWER;
    }
    build_room(l,t,e,rsi,i);
    sewer_corridor(l,t,-1,-1,lchar);
    sewer_corridor(l+e,t,1,-1,lchar);
    sewer_corridor(l,t+e,-1,1,lchar);
    sewer_corridor(l+e,t+e,1,1,lchar);
  }
  if (Current_Dungeon == E_SEWERS) {
    if ((Level->depth == SEWERLEVELS) && (! gamestatusp(COMPLETED_SEWERS))) {
      findspace(&tx,&ty,-1);
      Level->mlist = ((pml) checkmalloc(sizeof(mltype)));
      Level->mlist->next = NULL;
      Level->mlist->m = 
	Level->site[tx][ty].creature = 
	  ((pmt) make_creature(GREAT_WYRM)); /* The Great Wyrm */
      Level->mlist->m->x = tx;
      Level->mlist->m->y = ty;
    }
  }
}


void sewer_corridor(int x, int y, int dx, int dy, Symbol locchar)
{
  int continuing = TRUE;
  makedoor(x,y);
  x+=dx;
  y+=dy;
  while(continuing) {
    Level->site[x][y].locchar = locchar;
    if (locchar == WATER)
      Level->site[x][y].p_locf = L_WATER;
    else Level->site[x][y].p_locf = L_NO_OP;
    Level->site[x][y].roomnumber = RS_SEWER_DUCT;
    x+=dx;
    y+=dy;
  if (locchar == WATER)
    continuing = (inbounds(x,y) && 
		  ((Level->site[x][y].locchar == WALL) ||
		   (Level->site[x][y].locchar == WATER)));
  else
    continuing = (inbounds(x,y) && 
		  ((Level->site[x][y].roomnumber == RS_WALLSPACE) ||
		   (Level->site[x][y].roomnumber == RS_SEWER_DUCT)));
  }
  if (inbounds(x,y))
    makedoor(x,y);
}


void install_specials(void)
{
  int i,j,x,y;

  for(x=0;x<Level->level_width;x++)
    for(y=0;y<Level->level_length;y++)
      if ((Level->site[x][y].locchar == FLOOR) &&
	  (Level->site[x][y].p_locf == L_NO_OP) &&
	  (random_range(300) < difficulty())) {
	i = random_range(100);
	if (i < 10) {
	  Level->site[x][y].locchar = ALTAR;
	  Level->site[x][y].p_locf = L_ALTAR;
	  Level->site[x][y].aux = random_range(10);
	}
	else if (i < 20) {
	  Level->site[x][y].locchar = WATER;
	  Level->site[x][y].p_locf = L_MAGIC_POOL;
	}
	else if (i < 35) {
	  Level->site[x][y].locchar = RUBBLE;
	  Level->site[x][y].p_locf = L_RUBBLE;
	}
	else if (i < 40) {
	  Level->site[x][y].locchar = LAVA;
	  Level->site[x][y].p_locf = L_LAVA;
	}
	else if (i < 45) {
	  Level->site[x][y].locchar = FIRE;
	  Level->site[x][y].p_locf = L_FIRE;
	}
	else if ((i < 50) && (Current_Environment != E_ASTRAL)) {
	  Level->site[x][y].locchar = LIFT;
	  Level->site[x][y].p_locf = L_LIFT;
	}
	else if ((i < 55) && (Current_Environment != E_VOLCANO)) {
	  Level->site[x][y].locchar = HEDGE;
	  Level->site[x][y].p_locf = L_HEDGE;
	}
	else if (i < 57) {
	  Level->site[x][y].locchar = HEDGE;
	  Level->site[x][y].p_locf = L_TRIFID;
	}
	else if (i< 70) {
	  Level->site[x][y].locchar = STATUE;
	  if (random_range(100) < difficulty()) 
	    for (j=0;j<8;j++) {
	      if (Level->site[x+Dirs[0][j]][y+Dirs[1][j]].p_locf != L_NO_OP)
		Level->site[x+Dirs[0][j]][y+Dirs[1][j]].locchar = FLOOR;
	      Level->site[x+Dirs[0][j]][y+Dirs[1][j]].p_locf = 
		L_STATUE_WAKE;
	    }
	}
	else {
	  if (Current_Environment == E_VOLCANO) {
	    Level->site[x][y].locchar = LAVA;
	    Level->site[x][y].p_locf = L_LAVA;
	  }
	  else if (Current_Environment == E_ASTRAL) {
	    if (Level->depth == 1) {
	      Level->site[x][y].locchar = RUBBLE;
	      Level->site[x][y].p_locf = L_RUBBLE;
	    }
	    else if (Level->depth == 2) {
	      Level->site[x][y].locchar = FIRE;
	      Level->site[x][y].p_locf = L_FIRE;
	    }
	    else if (Level->depth == 3) {
	      Level->site[x][y].locchar = WATER;
	      Level->site[x][y].p_locf = L_WATER;
	    }
	    else if (Level->depth == 4) {
	      Level->site[x][y].locchar = ABYSS;
	      Level->site[x][y].p_locf = L_ABYSS;
	    }
	  }
	  else {
	    Level->site[x][y].locchar = WATER;
	    Level->site[x][y].p_locf = L_WATER;
	  }
	}
      }
}