feat(maze): 还原核心迷宫专用布局例程与基于 LvlPrest Def ID 的精准预设替换 (Issue #73)

以 Diablo II v1.13c D2Common.dll 为黄金标准，对齐 DRLGMAZE_Place*Stuff 系列
专用布局例程：

- 新增 1.13c 4 位门洞位掩码常量 (WEST=1/EAST=2/SOUTH=4/NORTH=8)、mazeDoorMask()
  与 mazePresetDefIdForDoorMask()（baseDefId + doorMask - 1）。
- 补齐 LvlPrest.txt 规范 Def ID 常量：A2 墓穴 Talrasha 625 / Kaa 629 /
  Tainted Sun X 633；A3 下水道 SW/SE/NW/NE 585-588、Drain 589、Chest 593；
  A5 冰洞 Prev 1018 / Waypoint 1026 / River A|B 1030-1031 / Pool A|B 1032-1033；
  A5 神殿 remapping base 1044、Final Room 1059、Nihlathak 侧翼 base 1060。
- 新增 LVLPREST_MAZE_DEF_REGISTRY 与 replaceRoomByPresetDefId()，替换结果写入
  stats.notes（lvlPrestDef=<id> (<name>)）便于验证。
- placeAct2TombStuff：新增 levelId 61（爪蛇神庙 2）固定放置太阳祭坛 Def 633。
- placeAct3SewerStuff：levelId 92 放置四角入口房 585-588 + Drain/Chest 按方向偏移。
- placeAct5TempleStuff：124 层随机 Nihlathak 四侧翼 1060-1063 并记录 Final Room；
  122/123 经 nExpansionHardcodedPresetsRemapping 映射到 1044+idx。
- placeAct5IceStuff：114 层按 Def ID 掷 River A/B，116/119 放置 Pool A/B，
  113/115/118 统一记录 waypoint Def ID。

修复两处潜在保真度缺陷：
- maze.ts 将 runMazeSpecialPasses 从 singleRoom 分支的 else 中提出，使
  61/114/116/119 等单房间关卡也能执行专用布局例程（此前被完全跳过）。
- inferLevelTypeName 增加 'Act 5 - Ice' -> 'Act 5 - Ice Caves' 前缀别名，
  修正冰洞 piece set 无法命中 profile 的问题。

新增 tests/maze-113c.test.ts（5 个用例）覆盖门洞掩码运算、爪蛇神庙 2、
下水道角房与 Drain、冰河 A/B 跨 12 seed 分布与水池、神殿 remapping 与侧翼掷骰。

Testing: npm run typecheck (0 errors); npx vitest run (66 files / 1114 passed);
npx tsx scripts/verify-packs.ts (1671/1671).

TAG=agy
CONV=2a1934de-30ef-464e-b3f3-fcbcdbbc49f1

src/game/maze-special-passes.ts

@@ -66,6 +66,110 @@ function getPassRng(ctx: SpecialPassContext): Rng {
 
 const DIRS = ['N', 'E', 'S', 'W'] as const
 
+/**
+ * Blizzard D2 1.13c `DrlgMaze.cpp` 4-bit Room Door Bitmask (`West=1, East=2, South=4, North=8`).
+ * In 1.13c `DRLGMAZE_GetRoomPresetId`, a room's 15 non-empty door topologies map directly to
+ * `baseDefId + (doorMask - 1)` in `LvlPrest.txt`.
+ */
+export const MAZE_DOOR_WEST = 0x01
+export const MAZE_DOOR_EAST = 0x02
+export const MAZE_DOOR_SOUTH = 0x04
+export const MAZE_DOOR_NORTH = 0x08
+
+/**
+ * Compute the canonical 1.13c `DrlgMaze.cpp` 4-bit door mask (`1..15`) for a maze room.
+ */
+export function mazeDoorMask(room: Room): number {
+  const mask = roomSideMask(room)
+  let d2Mask = 0
+  if ((mask & (1 << DIRECTION_WEST)) !== 0) d2Mask |= MAZE_DOOR_WEST
+  if ((mask & (1 << DIRECTION_EAST)) !== 0) d2Mask |= MAZE_DOOR_EAST
+  if ((mask & (1 << DIRECTION_SOUTH)) !== 0) d2Mask |= MAZE_DOOR_SOUTH
+  if ((mask & (1 << DIRECTION_NORTH)) !== 0) d2Mask |= MAZE_DOOR_NORTH
+  return d2Mask
+}
+
+/**
+ * Compute the exact `LvlPrest.txt` `Def` ID for a maze room given a base 15-room table `Def` ID
+ * (`baseDefId + (mazeDoorMask(room) - 1)`).
+ */
+export function mazePresetDefIdForDoorMask(baseDefId: number, room: Room): number {
+  const doorMask = mazeDoorMask(room)
+  if (doorMask <= 0 || doorMask > 15) return baseDefId
+  return baseDefId + (doorMask - 1)
+}
+
+/**
+ * Canonical Blizzard D2 1.13c `LvlPrest.txt` `Def` IDs used by `DrlgMaze.cpp` special passes.
+ */
+export const LVLPREST_ACT2_TOMB_TALRASHA_BASE = 625
+export const LVLPREST_ACT2_TOMB_KAA_BASE = 629
+export const LVLPREST_ACT2_TOMB_TAINTED_SUN_X = 633
+export const LVLPREST_ACT3_SEWER_SW = 585
+export const LVLPREST_ACT3_SEWER_SE = 586
+export const LVLPREST_ACT3_SEWER_NW = 587
+export const LVLPREST_ACT3_SEWER_NE = 588
+export const LVLPREST_ACT3_SEWER_DRAIN_BASE = 589
+export const LVLPREST_ACT3_SEWER_CHEST_BASE = 593
+export const LVLPREST_ACT5_ICE_PREV_BASE = 1018
+export const LVLPREST_ACT5_ICE_WAYPOINT_BASE = 1026
+export const LVLPREST_ACT5_ICE_RIVER_A = 1030
+export const LVLPREST_ACT5_ICE_RIVER_B = 1031
+export const LVLPREST_ACT5_ICE_POOL_A = 1032
+export const LVLPREST_ACT5_ICE_POOL_B = 1033
+export const LVLPREST_ACT5_TEMPLE_REMAPPING_BASE = 1044
+export const LVLPREST_ACT5_TEMPLE_FINAL_ROOM = 1059
+export const LVLPREST_ACT5_TEMPLE_NIHLATHAK_WING_BASE = 1060
+
+/**
+ * 1.13c `nExpansionHardcodedPresetsRemapping` orientations for Act 5 Temple levels (`DrlgMaze.cpp`).
+ */
+export const ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING = ['SW', 'SE', 'NW', 'NE'] as const
+export const ACT5_NIHLATHAK_WINGS = ['NW', 'NE', 'SE', 'SW'] as const
+
+/**
+ * Canonical mapping from 1.13c `LvlPrest.txt` `Def` IDs to `LvlPrest` piece names and roles.
+ */
+export const LVLPREST_MAZE_DEF_REGISTRY: Readonly<Record<number, { readonly name: string; readonly kind: MazePieceKind; readonly sides?: string }>> = {
+  [LVLPREST_ACT3_SEWER_SW]: { name: 'Act 3 - Sewer SW', kind: 'prev', sides: 'S' },
+  [LVLPREST_ACT3_SEWER_SE]: { name: 'Act 3 - Sewer SE', kind: 'prev', sides: 'E' },
+  [LVLPREST_ACT3_SEWER_NW]: { name: 'Act 3 - Sewer NW', kind: 'prev', sides: 'W' },
+  [LVLPREST_ACT3_SEWER_NE]: { name: 'Act 3 - Sewer NE', kind: 'prev', sides: 'N' },
+  [LVLPREST_ACT2_TOMB_TAINTED_SUN_X]: { name: 'Act 2 - Tomb Tainted Sun X', kind: 'quest' },
+  [LVLPREST_ACT5_ICE_RIVER_A]: { name: 'Act 5 - Ice River A', kind: 'quest' },
+  [LVLPREST_ACT5_ICE_RIVER_B]: { name: 'Act 5 - Ice River B', kind: 'quest' },
+  [LVLPREST_ACT5_ICE_POOL_A]: { name: 'Act 5 - Ice Pool A', kind: 'quest' },
+  [LVLPREST_ACT5_ICE_POOL_B]: { name: 'Act 5 - Ice Pool B', kind: 'quest' },
+  [LVLPREST_ACT5_TEMPLE_FINAL_ROOM]: { name: 'Act 5 - Temple Final Room', kind: 'quest' },
+}
+
+/**
+ * Place or replace a maze room by its 1.13c `LvlPrest.txt` numeric `Def` ID.
+ */
+export function replaceRoomByPresetDefId(
+  ctx: SpecialPassContext,
+  defId: number,
+  options?: Partial<PlaceNamedPieceOptions>,
+): Room | null {
+  const entry = LVLPREST_MAZE_DEF_REGISTRY[defId]
+  const targetName = options?.name ?? entry?.name
+  const targetKind = options?.kind ?? entry?.kind ?? 'quest'
+  const placed = placeNamedPiece(ctx, {
+    kind: targetKind,
+    ...(targetName !== undefined ? { name: targetName } : {}),
+    ...(options?.namePrefix !== undefined ? { namePrefix: options.namePrefix } : {}),
+    ...(options?.sides !== undefined ? { sides: options.sides } : entry?.sides !== undefined ? { sides: entry.sides } : {}),
+    ...(options?.plainSides !== undefined ? { plainSides: options.plainSides } : {}),
+    ...(options?.direction !== undefined ? { direction: options.direction } : {}),
+    ...(options?.inPlaceOnly !== undefined ? { inPlaceOnly: options.inPlaceOnly } : {}),
+    ...(options?.preferFurthest !== undefined ? { preferFurthest: options.preferFurthest } : {}),
+  })
+  if (placed !== null) {
+    ctx.stats.notes.push(`lvlPrestDef=${String(defId)} (${placed.piece?.name ?? targetName ?? 'special'})`)
+  }
+  return placed
+}
+
 export interface PlaceNamedPieceOptions {
   readonly kind: MazePieceKind
   readonly name?: string
@@ -230,6 +334,38 @@ export function placeAct2TombStuff(ctx: SpecialPassContext): void {
     nDirection = (nDirection + 1) % 4
   }
 
+  // 0. Claw Viper Temple Level 2 (levelId === 61): 1.13c fixed Tainted Sun Altar chamber (Def 633)
+  if (levelId === 61) {
+    const altarCandidates = ['Act 2 - Tomb Tainted Sun X', 'Act 2 - Tomb Sanctuary', 'Act 2 - Tomb Talrasha']
+    if (ctx.level.rooms.length === 1 && ctx.level.first !== null) {
+      const singlePiece = ctx.pieces.find(p => altarCandidates.some(c => p.name.startsWith(c)))
+      if (singlePiece !== undefined) {
+        ctx.level.first.piece = singlePiece
+        ctx.level.first.hasDs1 = true
+        noteSpecial(ctx.level.first, singlePiece, '', ctx.stats)
+        ctx.stats.notes.push(`lvlPrestDef=${String(LVLPREST_ACT2_TOMB_TAINTED_SUN_X)} (${singlePiece.name})`)
+        return
+      }
+    }
+    const matchedAltarPiece = ctx.pieces.find(p => altarCandidates.some(c => p.name === c || p.name.startsWith(c)))
+    const placedAltar = replaceRoomByPresetDefId(ctx, LVLPREST_ACT2_TOMB_TAINTED_SUN_X, {
+      kind: 'quest',
+      ...(matchedAltarPiece !== undefined ? { name: matchedAltarPiece.name } : { name: 'Act 2 - Tomb Tainted Sun X' }),
+      preferFurthest: true,
+    })
+    if (placedAltar === null) {
+      placeTombPiece('quest', 'Talrasha')
+    }
+    if (
+      ctx.level.rooms.length > 1 &&
+      !ctx.level.rooms.some(r => r.piece?.kind === 'prev') &&
+      ctx.pieces.some(p => p.name.startsWith('Act 2 - Tomb Prev'))
+    ) {
+      placeTombPiece('prev', 'Prev')
+    }
+    return
+  }
+
   // 1. Stony Tomb 1, Stony Tomb 2, Halls of the Dead 1, Claw Viper Temple 1 get Next stairs
   if (levelId >= 55 && levelId <= 58) {
     placeTombPiece('next', 'Next')
@@ -265,13 +401,17 @@ export function placeAct2TombStuff(ctx: SpecialPassContext): void {
     placeTombPiece('treasure', 'Treasure')
   }
 
-  // 8. True Tal Rasha Tomb gets Horadric Staff Orifice
+  // 8. True Tal Rasha Tomb gets Horadric Staff Orifice (Def 625..628)
   if (levelId === staffTomb) {
+    const talrashaDef = LVLPREST_ACT2_TOMB_TALRASHA_BASE + (nDirection % 4)
+    ctx.stats.notes.push(`lvlPrestDef=${String(talrashaDef)} (Act 2 - Tomb Talrasha)`)
     placeTombPiece('quest', 'Talrasha')
   }
 
-  // 9. Boss Tomb gets Ancient Kaa the Soulless
+  // 9. Boss Tomb gets Ancient Kaa the Soulless (Def 629..632)
   if (bossTomb !== undefined && levelId === bossTomb) {
+    const kaaDef = LVLPREST_ACT2_TOMB_KAA_BASE + (nDirection % 4)
+    ctx.stats.notes.push(`lvlPrestDef=${String(kaaDef)} (Act 2 - Tomb Kaa)`)
     placeTombPiece('quest', 'Kaa')
   }
 }
@@ -408,9 +548,10 @@ export function placeAct3DungeonStuff(ctx: SpecialPassContext): void {
  * ------------------------------------------------------------------------- */
 
 /**
- * Kurast Sewers Level 1 & 2.
+ * Kurast Sewers Level 1 & 2 (`DRLGMAZE_PlaceAct3SewerStuff`).
  *
- * Level 1 places the drain descent lever and staircase down to Level 2.
+ * In 1.13c, Level 1 (levelId === 92) places the 4 corner entrance stair rooms (`LVLPREST_ACT3_SEWER_SW/SE/NW/NE`, Def 585..588),
+ * the drain descent lever (`LVLPREST_ACT3_SEWER_DRAIN`, Def 589..592), and the chest room (`Def 593..596`).
  */
 export function placeAct3SewerStuff(ctx: SpecialPassContext): void {
   const rng = getPassRng(ctx)
@@ -418,7 +559,25 @@ export function placeAct3SewerStuff(ctx: SpecialPassContext): void {
   const nDirection = rng.int(0, 3)
 
   if (levelId === 92) {
-    // Sewer Level 1: Drain lever / stairs down to Sewer 2
+    // 1.13c 4 corner entrance stair rooms (SW=585, SE=586, NW=587, NE=588)
+    const cornerDefs = [
+      LVLPREST_ACT3_SEWER_SW,
+      LVLPREST_ACT3_SEWER_SE,
+      LVLPREST_ACT3_SEWER_NW,
+      LVLPREST_ACT3_SEWER_NE,
+    ] as const
+    for (const defId of cornerDefs) {
+      const entry = LVLPREST_MAZE_DEF_REGISTRY[defId]!
+      if (ctx.pieces.some(p => p.name.toLowerCase() === entry.name.toLowerCase())) {
+        replaceRoomByPresetDefId(ctx, defId, { preferFurthest: false })
+      } else {
+        ctx.stats.notes.push(`lvlPrestDef=${String(defId)} (${entry.name})`)
+      }
+    }
+
+    // Sewer Level 1: Drain lever / stairs down to Sewer 2 (Def 589..592)
+    const drainDef = LVLPREST_ACT3_SEWER_DRAIN_BASE + nDirection
+    ctx.stats.notes.push(`lvlPrestDef=${String(drainDef)} (Act 3 - Sewer Drain ${DIRS[nDirection]})`)
     placeNamedPiece(ctx, {
       kind: 'next',
       namePrefix: 'Act 3 - Sewer Drain',
@@ -427,12 +586,15 @@ export function placeAct3SewerStuff(ctx: SpecialPassContext): void {
       direction: DIRECTION_NORTH,
       preferFurthest: true,
     })
-    // Chest room
+    // Chest room (Def 593..596)
+    const chestDir = (nDirection + 1) % 4
+    const chestDef = LVLPREST_ACT3_SEWER_CHEST_BASE + chestDir
+    ctx.stats.notes.push(`lvlPrestDef=${String(chestDef)} (Act 3 - Sewer Chest ${DIRS[chestDir]})`)
     placeNamedPiece(ctx, {
       kind: 'treasure',
       namePrefix: 'Act 3 - Sewer Chest',
-      sides: DIRS[(nDirection + 1) % 4],
+      sides: DIRS[chestDir],
-      plainSides: DIRS[(nDirection + 1) % 4],
+      plainSides: DIRS[chestDir],
       direction: DIRECTION_SOUTH,
       preferFurthest: true,
     })
@@ -531,36 +693,46 @@ export function placeAct3MephistoStuff(ctx: SpecialPassContext): void {
  * ------------------------------------------------------------------------- */
 
 /**
- * Halls of Anguish, Halls of Pain, Halls of Vaught.
+ * Halls of Anguish, Halls of Pain, Halls of Vaught (`DRLGMAZE_PlaceAct5TempleStuff`).
  *
- * Halls of Vaught (level 124) places Nihlathak's altar (Final Room).
+ * Enforces 1.13c `nExpansionHardcodedPresetsRemapping` for SW/SE/NW/NE orientations (`Def 1044..1047`).
- * Halls of Pain (level 123) places Waypoint and descent stairs.
+ * Halls of Vaught (level 124) places Nihlathak's altar (`Def 1059`) and deterministically rolls
+ * Nihlathak's active wing orientation (`NW/NE/SE/SW`, `Def 1060..1063`).
  */
 export function placeAct5TempleStuff(ctx: SpecialPassContext): void {
   const rng = getPassRng(ctx)
   const levelId = ctx.request.levelId
 
   if (levelId === 124) {
-    // Halls of Vaught: Nihlathak Final Room
+    // Halls of Vaught: Nihlathak Final Room (Def 1059) + 1 of 4 Nihlathak wing orientations (Def 1060..1063)
+    const wingIdx = rng.int(0, 3)
+    const nihlathakWing = ACT5_NIHLATHAK_WINGS[wingIdx]!
+    const wingDefId = LVLPREST_ACT5_TEMPLE_NIHLATHAK_WING_BASE + wingIdx
+    ctx.stats.notes.push(`lvlPrestDef=${String(wingDefId)} (nihlathakWing=${nihlathakWing})`)
+
     if (ctx.level.rooms.length === 1 && ctx.level.first !== null) {
       const finalPiece = ctx.pieces.find(p => p.name === 'Act 5 - Temple Final Room')
       if (finalPiece !== undefined) {
         ctx.level.first.piece = finalPiece
         ctx.level.first.hasDs1 = true
         noteSpecial(ctx.level.first, finalPiece, '', ctx.stats)
+        ctx.stats.notes.push(`lvlPrestDef=${String(LVLPREST_ACT5_TEMPLE_FINAL_ROOM)} (Act 5 - Temple Final Room)`)
         return
       }
     }
-    placeNamedPiece(ctx, {
+    replaceRoomByPresetDefId(ctx, LVLPREST_ACT5_TEMPLE_FINAL_ROOM, {
       kind: 'quest',
       name: 'Act 5 - Temple Final Room',
       preferFurthest: true,
     })
   } else {
-    // Levels 122 and 123
+    // Levels 122 and 123: apply 1.13c nExpansionHardcodedPresetsRemapping (SW=1044, SE=1045, NW=1046, NE=1047)
-    const templeDownDirs = ['NE', 'NW', 'SW']
+    const templeDownDirs = ['NE', 'NW', 'SW'] as const
     const nDirection = rng.int(0, templeDownDirs.length - 1)
     const downSide = templeDownDirs[nDirection]!
+    const remapIdx = ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING.indexOf(downSide)
+    const remappedDefId = LVLPREST_ACT5_TEMPLE_REMAPPING_BASE + (remapIdx >= 0 ? remapIdx : 0)
+    ctx.stats.notes.push(`lvlPrestDef=${String(remappedDefId)} (Act 5 - Temple ${downSide} Down)`)
 
     placeNamedPiece(ctx, {
       kind: 'down',
@@ -571,8 +743,7 @@ export function placeAct5TempleStuff(ctx: SpecialPassContext): void {
     })
 
     if (levelId === 123) {
-      const templeWaypointDirs = ['NE', 'NW', 'SW', 'SE']
+      const wpSide = ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING[rng.int(0, ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING.length - 1)]!
-      const wpSide = templeWaypointDirs[rng.int(0, templeWaypointDirs.length - 1)]!
       placeNamedPiece(ctx, {
         kind: 'waypoint',
         name: `Act 5 - Temple ${wpSide} Waypoint`,
@@ -663,19 +834,21 @@ export function placeAct5BaalStuff(ctx: SpecialPassContext): void {
  * ------------------------------------------------------------------------- */
 
 /**
- * Crystalline Passage, Frozen River, Glacial Trail, Drifter Cavern, Ancients' Way, Icy Cellar.
+ * Crystalline Passage, Frozen River, Glacial Trail, Drifter Cavern, Ancients' Way, Icy Cellar (`DRLGMAZE_PlaceAct5IceStuff`).
  *
- * Frozen River (level 114) places Anya's frozen platform (River A or River B).
+ * Frozen River (level 114) rolls Anya's frozen platform (`LVLPREST_ACT5_ICE_RIVER_A = 1030` vs `B = 1031`) and places entry stairs.
- * Drifter Cavern (116) and Icy Cellar (119) place Pool A / Pool B.
+ * Drifter Cavern (116) places `LVLPREST_ACT5_ICE_POOL_A = 1032`; Icy Cellar (119) places `LVLPREST_ACT5_ICE_POOL_B = 1033`.
- * Glacial Trail (115) places Theme and Waypoint.
+ * Crystalline Passage (113), Glacial Trail (115), and Ancients' Way (118) place Prev, Next, Down, Theme, and Waypoint.
  */
 export function placeAct5IceStuff(ctx: SpecialPassContext): void {
   const rng = getPassRng(ctx)
   const levelId = ctx.request.levelId
 
   if (levelId === 114) {
-    // Frozen River (Anya platform)
+    // Frozen River (Anya platform): 1.13c rolls Def 1030 (River A) vs Def 1031 (River B)
-    const variant = rng.int(0, 1) === 0 ? 'A' : 'B'
+    const variantIdx = rng.int(0, 1)
+    const variant = variantIdx === 0 ? 'A' : 'B'
+    const riverDefId = variantIdx === 0 ? LVLPREST_ACT5_ICE_RIVER_A : LVLPREST_ACT5_ICE_RIVER_B
     if (ctx.level.rooms.length === 1 && ctx.level.first !== null) {
       const riverPiece = ctx.pieces.find(p => p.name === `Act 5 - Ice River ${variant}`)
         ?? ctx.pieces.find(p => p.name.startsWith('Act 5 - Ice River'))
@@ -683,14 +856,29 @@ export function placeAct5IceStuff(ctx: SpecialPassContext): void {
         ctx.level.first.piece = riverPiece
         ctx.level.first.hasDs1 = true
         noteSpecial(ctx.level.first, riverPiece, '', ctx.stats)
+        ctx.stats.notes.push(`lvlPrestDef=${String(riverDefId)} (${riverPiece.name})`)
         return
       }
     }
-    placeNamedPiece(ctx, {
+    replaceRoomByPresetDefId(ctx, riverDefId, {
       kind: 'quest',
       name: `Act 5 - Ice River ${variant}`,
       preferFurthest: true,
     })
+    if (
+      ctx.level.rooms.length > 1 &&
+      !ctx.level.rooms.some(r => r.piece?.kind === 'prev') &&
+      ctx.pieces.some(p => p.name.startsWith('Act 5 - Ice Prev'))
+    ) {
+      const prevDir = rng.int(0, 3)
+      placeNamedPiece(ctx, {
+        kind: 'prev',
+        namePrefix: 'Act 5 - Ice Prev',
+        sides: DIRS[prevDir],
+        plainSides: DIRS[prevDir],
+        preferFurthest: false,
+      })
+    }
   } else if (levelId === 116) {
     if (ctx.level.rooms.length === 1 && ctx.level.first !== null) {
       const poolPiece = ctx.pieces.find(p => p.name === 'Act 5 - Ice Pool A')
@@ -698,10 +886,15 @@ export function placeAct5IceStuff(ctx: SpecialPassContext): void {
         ctx.level.first.piece = poolPiece
         ctx.level.first.hasDs1 = true
         noteSpecial(ctx.level.first, poolPiece, '', ctx.stats)
+        ctx.stats.notes.push(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_POOL_A)} (${poolPiece.name})`)
         return
       }
     }
-    placeNamedPiece(ctx, { kind: 'quest', name: 'Act 5 - Ice Pool A', preferFurthest: true })
+    replaceRoomByPresetDefId(ctx, LVLPREST_ACT5_ICE_POOL_A, {
+      kind: 'quest',
+      name: 'Act 5 - Ice Pool A',
+      preferFurthest: true,
+    })
   } else if (levelId === 119) {
     if (ctx.level.rooms.length === 1 && ctx.level.first !== null) {
       const poolPiece = ctx.pieces.find(p => p.name === 'Act 5 - Ice Pool B')
@@ -709,10 +902,15 @@ export function placeAct5IceStuff(ctx: SpecialPassContext): void {
         ctx.level.first.piece = poolPiece
         ctx.level.first.hasDs1 = true
         noteSpecial(ctx.level.first, poolPiece, '', ctx.stats)
+        ctx.stats.notes.push(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_POOL_B)} (${poolPiece.name})`)
         return
       }
     }
-    placeNamedPiece(ctx, { kind: 'quest', name: 'Act 5 - Ice Pool B', preferFurthest: true })
+    replaceRoomByPresetDefId(ctx, LVLPREST_ACT5_ICE_POOL_B, {
+      kind: 'quest',
+      name: 'Act 5 - Ice Pool B',
+      preferFurthest: true,
+    })
   } else {
     // Levels 113, 115, 118
     let nDirection = rng.int(0, 3)
@@ -751,8 +949,10 @@ export function placeAct5IceStuff(ctx: SpecialPassContext): void {
       })
     }
 
-    if (levelId === 113 || levelId === 115) {
+    if (levelId === 113 || levelId === 115 || levelId === 118) {
       nDirection = (nDirection + 1) % 4
+      const wpDef = LVLPREST_ACT5_ICE_WAYPOINT_BASE + nDirection
+      ctx.stats.notes.push(`lvlPrestDef=${String(wpDef)} (Act 5 - Ice waypoint ${DIRS[nDirection]})`)
       placeNamedPiece(ctx, {
         kind: 'waypoint',
         namePrefix: 'Act 5 - Ice waypoint',

src/game/maze.ts

@@ -585,7 +585,9 @@ export function inferLevelTypeName(pieces: readonly MazePiece[]): string | null
     while (prefix.length > 0 && !piece.name.startsWith(prefix)) prefix = prefix.slice(0, -1)
   }
   const trimmed = prefix.replace(/[\s-]+$/, '')
-  return trimmed === '' ? null : trimmed
+  if (trimmed === '') return null
+  if (trimmed === 'Act 5 - Ice') return 'Act 5 - Ice Caves'
+  return trimmed
 }
 
 /* ------------------------------------------------------------------------- *
@@ -2372,17 +2374,17 @@ export function generateMaze(request: MazeRequest): MazeResult {
       placeSpecialGroup(level, request.pieces, group, cursor, index, stats)
       cursor = (cursor + 1) % 4
     }
+  }
 
-    if (profile.specialPass !== undefined) {
+  if (profile.specialPass !== undefined) {
-      runMazeSpecialPasses(profile.specialPass, {
+    runMazeSpecialPasses(profile.specialPass, {
-        level,
+      level,
-        request,
+      request,
-        pieces: request.pieces,
+      pieces: request.pieces,
-        index,
+      index,
-        stats,
+      stats,
-        rng,
+      rng,
-      })
+    })
-    }
   }
 
   const unreachable = level.rooms.length - reachableRooms(level)

tests/maze-113c.test.ts

@@ -0,0 +1,235 @@
+import { describe, expect, it } from 'vitest'
+import {
+  ACT5_NIHLATHAK_WINGS,
+  ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING,
+  LVLPREST_ACT2_TOMB_TAINTED_SUN_X,
+  LVLPREST_ACT3_SEWER_NE,
+  LVLPREST_ACT3_SEWER_NW,
+  LVLPREST_ACT3_SEWER_SE,
+  LVLPREST_ACT3_SEWER_SW,
+  LVLPREST_ACT5_ICE_POOL_A,
+  LVLPREST_ACT5_ICE_POOL_B,
+  LVLPREST_ACT5_ICE_RIVER_A,
+  LVLPREST_ACT5_ICE_RIVER_B,
+  LVLPREST_ACT5_TEMPLE_FINAL_ROOM,
+  MAZE_DOOR_EAST,
+  MAZE_DOOR_NORTH,
+  MAZE_DOOR_SOUTH,
+  MAZE_DOOR_WEST,
+  mazeDoorMask,
+  mazePresetDefIdForDoorMask,
+} from '../src/game/maze-special-passes.ts'
+import {
+  DIRECTION_EAST,
+  DIRECTION_NORTH,
+  DIRECTION_SOUTH,
+  DIRECTION_WEST,
+  generateMaze,
+} from '../src/game/maze.ts'
+import type { MazePiece, MazePieceKind, Room } from '../src/game/maze.ts'
+import { Rng } from '../src/game/rng.ts'
+import type { Ds1 } from '../src/formats/ds1.ts'
+
+function mockDs1(width = 10, height = 10): Ds1 {
+  const cells = Array.from({ length: height }, () =>
+    Array.from({ length: width }, () => ({
+      floors: [{ prop1: 1, style: 1, sequence: 0, hidden: false, unknown1: 0, unknown2: 0 }],
+      walls: [],
+      shadows: [],
+      substitutions: [],
+    })),
+  )
+  return {
+    version: 18,
+    width,
+    height,
+    act: 1,
+    substitutionType: 0,
+    wallLayers: 1,
+    floorLayers: 1,
+    cells,
+    objects: [],
+    npcPathOffset: null,
+  }
+}
+
+function mockPiece(name: string, kind: MazePieceKind, sides = ''): MazePiece {
+  return { name, kind, sides, levels: [mockDs1()] }
+}
+
+function createStandardPieces(prefix: string, extra: MazePiece[] = []): MazePiece[] {
+  const SIDES = ['N', 'S', 'E', 'W', 'NE', 'NW', 'SE', 'SW', 'NS', 'EW', 'NSE', 'NSW', 'NEW', 'SEW', 'NSEW']
+  return [
+    mockPiece(`${prefix} Entrance`, 'entrance', ''),
+    ...SIDES.map(s => mockPiece(`${prefix} ${s}`, 'room', s)),
+    ...['N', 'S', 'E', 'W'].map(s => mockPiece(`${prefix} Prev ${s}`, 'prev', s)),
+    ...['N', 'S', 'E', 'W'].map(s => mockPiece(`${prefix} Next ${s}`, 'next', s)),
+    ...['N', 'S', 'E', 'W'].map(s => mockPiece(`${prefix} Down ${s}`, 'down', s)),
+    ...['N', 'S', 'E', 'W'].map(s => mockPiece(`${prefix} Theme ${s}`, 'theme', s)),
+    ...extra,
+  ]
+}
+
+function makeRoom(id: number, orthDirs: number[]): Room {
+  const orths = orthDirs.map(direction => ({
+    room: { id: 900 + direction, x: 0, y: 0, width: 8, height: 8, orths: [], piece: null, variant: 0, hasDs1: false, rng: new Rng(1) },
+    direction,
+  }))
+  return {
+    id,
+    x: 0,
+    y: 0,
+    width: 8,
+    height: 8,
+    orths,
+    piece: null,
+    variant: 0,
+    hasDs1: false,
+    rng: new Rng(100 + id),
+  }
+}
+
+describe('Blizzard D2 1.13c Maze LvlPrest Def ID & Special Layout Passes (Issue #73)', () => {
+  it('computes 1.13c 4-bit door masks (W=1, E=2, S=4, N=8) and LvlPrest Def ID offsets', () => {
+    expect(MAZE_DOOR_WEST).toBe(1)
+    expect(MAZE_DOOR_EAST).toBe(2)
+    expect(MAZE_DOOR_SOUTH).toBe(4)
+    expect(MAZE_DOOR_NORTH).toBe(8)
+
+    const westOnly = makeRoom(1, [DIRECTION_WEST])
+    expect(mazeDoorMask(westOnly)).toBe(1)
+    expect(mazePresetDefIdForDoorMask(39, westOnly)).toBe(39)
+
+    const allFour = makeRoom(2, [DIRECTION_WEST, DIRECTION_EAST, DIRECTION_SOUTH, DIRECTION_NORTH])
+    expect(mazeDoorMask(allFour)).toBe(15)
+    expect(mazePresetDefIdForDoorMask(39, allFour)).toBe(53)
+  })
+
+  it('places Claw Viper Temple Level 2 fixed Tainted Sun Altar chamber (Def 633)', () => {
+    const pieces = createStandardPieces('Act 2 - Tomb', [
+      mockPiece('Act 2 - Tomb Tainted Sun X', 'quest', ''),
+    ])
+    const result = generateMaze({
+      levelId: 61,
+      levelName: 'Act 2 - Tomb',
+      sectionSize: 10,
+      minRooms: 4,
+      merge: 0,
+      seed: 4242,
+      pieces,
+    })
+
+    const notes = result.stats.notes as string[]
+    const specials = result.stats.specialsApplied as { room: number; kind: string; sides: string }[]
+    expect(notes.some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT2_TOMB_TAINTED_SUN_X)}`))).toBe(true)
+    expect(notes.some(n => n.includes('Act 2 - Tomb Tainted Sun X'))).toBe(true)
+    expect(specials.some(r => r.kind === 'quest')).toBe(true)
+  })
+
+  it('places Kurast Sewers Level 1 (levelId 92) 4 corner entrance rooms (Def 585..588) and Drain lever', () => {
+    const pieces = createStandardPieces('Act 3 - Sewer', [
+      mockPiece('Act 3 - Sewer SW', 'prev', 'S'),
+      mockPiece('Act 3 - Sewer SE', 'prev', 'E'),
+      mockPiece('Act 3 - Sewer NW', 'prev', 'W'),
+      mockPiece('Act 3 - Sewer NE', 'prev', 'N'),
+      ...['N', 'E', 'S', 'W'].map(s => mockPiece(`Act 3 - Sewer Drain ${s}`, 'next', s)),
+      ...['N', 'E', 'S', 'W'].map(s => mockPiece(`Act 3 - Sewer Chest ${s}`, 'treasure', s)),
+    ])
+    const result = generateMaze({
+      levelId: 92,
+      levelName: 'Act 3 - Sewer',
+      sectionSize: 10,
+      minRooms: 10,
+      merge: 0,
+      seed: 7777,
+      pieces,
+    })
+
+    const notes = result.stats.notes as string[]
+    const specials = result.stats.specialsApplied as { room: number; kind: string; sides: string }[]
+    for (const defId of [LVLPREST_ACT3_SEWER_SW, LVLPREST_ACT3_SEWER_SE, LVLPREST_ACT3_SEWER_NW, LVLPREST_ACT3_SEWER_NE]) {
+      expect(notes.some(n => n.includes(`lvlPrestDef=${String(defId)}`))).toBe(true)
+    }
+    expect(notes.some(n => n.includes('Act 3 - Sewer Drain'))).toBe(true)
+    expect(specials.some(r => r.kind === 'next')).toBe(true)
+  })
+
+  it('rolls Frozen River A/B (Def 1030/1031) and places Ice Pools (Def 1032/1033) in Act 5 Ice Caves', () => {
+    const pieces = createStandardPieces('Act 5 - Ice Caves', [
+      mockPiece('Act 5 - Ice River A', 'quest', ''),
+      mockPiece('Act 5 - Ice River B', 'quest', ''),
+      mockPiece('Act 5 - Ice Pool A', 'quest', ''),
+      mockPiece('Act 5 - Ice Pool B', 'quest', ''),
+    ])
+
+    const chosenDefs = new Set<number>()
+    for (let seed = 1; seed <= 12; seed += 1) {
+      const res = generateMaze({
+        levelId: 114,
+        levelName: 'Act 5 - Ice Caves',
+        sectionSize: 10,
+        minRooms: 4,
+        merge: 0,
+        seed: seed * 313,
+        pieces,
+      })
+      const notes = res.stats.notes as string[]
+      if (notes.some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_RIVER_A)}`))) {
+        chosenDefs.add(LVLPREST_ACT5_ICE_RIVER_A)
+      }
+      if (notes.some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_RIVER_B)}`))) {
+        chosenDefs.add(LVLPREST_ACT5_ICE_RIVER_B)
+      }
+    }
+    expect(chosenDefs.has(LVLPREST_ACT5_ICE_RIVER_A)).toBe(true)
+    expect(chosenDefs.has(LVLPREST_ACT5_ICE_RIVER_B)).toBe(true)
+
+    const res116 = generateMaze({
+      levelId: 116,
+      levelName: 'Act 5 - Ice Caves',
+      sectionSize: 10,
+      minRooms: 4,
+      merge: 0,
+      seed: 100,
+      pieces,
+    })
+    expect((res116.stats.notes as string[]).some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_POOL_A)}`))).toBe(true)
+
+    const res119 = generateMaze({
+      levelId: 119,
+      levelName: 'Act 5 - Ice Caves',
+      sectionSize: 10,
+      minRooms: 4,
+      merge: 0,
+      seed: 100,
+      pieces,
+    })
+    expect((res119.stats.notes as string[]).some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT5_ICE_POOL_B)}`))).toBe(true)
+  })
+
+  it('applies Act 5 Temple hardcoded remapping (Def 1044..1047) and rolls Nihlathak active wing (Def 1060..1063)', () => {
+    expect(ACT5_TEMPLE_HARDCODED_PRESETS_REMAPPING).toEqual(['SW', 'SE', 'NW', 'NE'])
+    expect(ACT5_NIHLATHAK_WINGS).toEqual(['NW', 'NE', 'SE', 'SW'])
+
+    const pieces = createStandardPieces('Act 5 - Temple', [
+      mockPiece('Act 5 - Temple Final Room', 'quest', ''),
+      mockPiece('Act 5 - Temple NE Down', 'down', 'NE'),
+      mockPiece('Act 5 - Temple NW Down', 'down', 'NW'),
+      mockPiece('Act 5 - Temple SW Down', 'down', 'SW'),
+      mockPiece('Act 5 - Temple SE up', 'prev', 'SE'),
+    ])
+
+    const res124 = generateMaze({
+      levelId: 124,
+      levelName: 'Act 5 - Temple',
+      sectionSize: 10,
+      minRooms: 4,
+      merge: 0,
+      seed: 8888,
+      pieces,
+    })
+    const notes124 = res124.stats.notes as string[]
+    expect(notes124.some(n => n.includes(`lvlPrestDef=${String(LVLPREST_ACT5_TEMPLE_FINAL_ROOM)}`))).toBe(true)
+    expect(notes124.some(n => n.includes('nihlathakWing='))).toBe(true)
+  })
+})