rgoue/game/newlevel.go

//nolint:mnd // C-faithful literals; names hurt C-greppability (approved 2026-07-07)
package game

// new_level.c — dig and draw a new level.

const (
	treasRoomChance = 20 // one chance in TREAS_ROOM for a treasure room
	maxTreas        = 10 // maximum number of treasures in a treasure room
	minTreas        = 2  // minimum number of treasures in a treasure room
	maxTries        = 10 // max number of tries to put down a monster
)

// NewLevel digs and draws a new level (new_level.c new_level).
func (g *RogueGame) NewLevel() {
	p := &g.Player
	p.Flags.Clear(Held) // unhold when you go down just in case

	if g.Depth > g.MaxDepth {
		g.MaxDepth = g.Depth
	}
	// Clean things off from last level
	for i := range g.Level.Places {
		g.Level.Places[i] = Place{Ch: ' ', Flags: FReal}
	}

	g.clear()
	// Free up the monsters on the last level; the objects and their packs
	// go with them (the garbage collector is our free_list).
	g.Level.Monsters = nil
	g.Level.Objects = nil
	g.digRooms()    // Draw rooms
	g.digPassages() // Draw passages

	p.NoFood++

	g.putThings() // Place objects (if any)
	// Place the traps
	if g.rnd(10) < g.Depth {
		g.Level.TrapCount = min(g.rnd(g.Depth/4)+1, MaxTraps)

		for i := g.Level.TrapCount; i > 0; i-- {
			// not only wouldn't it be NICE to have traps in mazes (not
			// that we care about being nice), since the trap number is
			// stored where the passage number is, we can't actually do it.
			var stairs Coord
			for {
				stairs, _ = g.findFloor(false)
				if g.Level.Char(stairs.Y, stairs.X) == Floor {
					break
				}
			}

			sp := g.Level.FlagsAt(stairs.Y, stairs.X)
			sp.Clear(FReal)
			*sp |= PlaceFlags(g.rnd(NumTrapTypes)) //nolint:gosec // G115: 0..7 fits
		}
	}
	// Place the staircase down.
	stairs, _ := g.findFloor(false)
	g.Level.Stairs = stairs
	g.Level.SetChar(stairs.Y, stairs.X, Stairs)
	g.SeenStairs = false

	for _, tp := range g.Level.Monsters {
		tp.Room = g.roomIn(tp.Pos)
	}

	hero, _ := g.findFloor(true)
	p.Pos = hero
	g.enterRoom(hero)
	g.mvaddch(hero.Y, hero.X, PlayerCh)

	if p.On(SenseMonsters) {
		g.turnSee(false)
	}

	if p.On(Hallucinating) {
		g.visuals(0)
	}
}

// randomRoom picks a room that is really there (new_level.c rnd_room).
func (g *RogueGame) randomRoom() int {
	for {
		rm := g.rnd(MaxRooms)
		if !g.Level.Rooms[rm].Flags.Has(Gone) {
			return rm
		}
	}
}

// putThings puts potions and scrolls on this level (new_level.c
// put_things).
func (g *RogueGame) putThings() {
	// Once you have found the amulet, the only way to get new stuff is to
	// go down into the dungeon.
	if g.HasAmulet && g.Depth < g.MaxDepth {
		return
	}
	// check for treasure rooms, and if so, put it in.
	if g.rnd(treasRoomChance) == 0 {
		g.treasureRoom()
	}
	// Do MAXOBJ attempts to put things on a level
	for range MaxObj {
		if g.rnd(100) < 36 {
			// Pick a new object and link it in the list
			obj := g.newThing()
			g.Level.AddObject(obj)
			// Put it somewhere
			obj.Pos, _ = g.findFloor(false)
			g.Level.SetChar(obj.Pos.Y, obj.Pos.X, obj.Kind.Glyph())
		}
	}
	// If he is really deep in the dungeon and he hasn't found the amulet
	// yet, put it somewhere on the ground
	if g.Depth >= AmuletLevel && !g.HasAmulet {
		obj := newObject()
		g.Level.AddObject(obj)
		obj.Damage = dice("0x0")
		obj.HurlDmg = dice("0x0")
		obj.ArmorClass = 11
		obj.Kind = KindAmulet
		// Put it somewhere
		obj.Pos, _ = g.findFloor(false)
		g.Level.SetChar(obj.Pos.Y, obj.Pos.X, Amulet)
	}
}

// treasureRoom adds a treasure room (new_level.c treas_room).
func (g *RogueGame) treasureRoom() {
	rp := &g.Level.Rooms[g.randomRoom()]

	spots := min((rp.Max.Y-2)*(rp.Max.X-2)-minTreas, maxTreas-minTreas)

	numMonst := g.rnd(spots) + minTreas
	for nm := numMonst; nm > 0; nm-- {
		mp, _ := g.findFloorIn(rp, 2*maxTries, false)
		tp := g.newThing()
		tp.Pos = mp
		g.Level.AddObject(tp)
		g.Level.SetChar(mp.Y, mp.X, tp.Kind.Glyph())
	}

	// fill up room with monsters from the next level down
	nm := max(g.rnd(spots)+minTreas, numMonst+2)

	spots = (rp.Max.Y - 2) * (rp.Max.X - 2)
	if nm > spots {
		nm = spots
	}

	g.Depth++
	for ; nm > 0; nm-- {
		if mp, ok := g.findFloorIn(rp, maxTries, true); ok {
			tp := &Monster{}
			g.newMonster(tp, g.randMonster(false), mp)
			tp.Flags.Set(Mean) // no sloughers in THIS room
			g.givePack(tp)
		}
	}

	g.Depth--
}