Handle level IDs in links correctly when loading/saving

extras/docs/fileformat.txt

@@ -185,11 +185,11 @@ Map links chunk
 
     numLinks records of:
 
-      UINT16  srcLevel          (max=numLevels-1)
+      UINT16  srcLevelIndex     (max=numLevels-1)
       UINT16  srcRow            (max=numRows-1    of the given level)
       UINT16  srcColumn         (max=numColumns-1 of the given level)
 
-      UINT16  destLevel         (max=numLevel-1)
+      UINT16  destLevelIndex    (max=numLevel-1)
       UINT16  destRow           (max=numRows-1    of the given level)
       UINT16  destColumn        (max=numColumns-1 of the given level)
 
@@ -205,7 +205,7 @@ App state chunks (in 'stat' group chunk, optional)
         '/', '\', ':', '*', '?', '"', '<', '>', '|', '^', <zero byte>
 
     UINT8   zoomLevel           (min=1, max=20)
-    UINT8   currLevel           (max=numLevels-1)
+    UINT8   currLevelIndex      (max=numLevels-1)
     UINT16  cursorRow           (max=numRows-1    of the given level)
     UINT16  cursorColumn        (max=numColumns-1 of the given level)
     UINT16  viewStartRow        (max=numRows-1    of the given level)
@@ -237,7 +237,7 @@ App state chunks (in 'stat' group chunk, optional)
 
     numLevels records of:
 
-        UINT32   levelId
+        UINT32   levelIndex
         UINT8    levelSection     (0=closed, 1=open)
 
         if numRegions > 0 for the level (enableRegions can still be 0):
@@ -254,9 +254,9 @@ Version 4
 [Gridmonger v1.2.0 - 2024-04-22]
 
   - Remove redundant region coordinates from the 'regn' chunk.
-  - Convert 'disp' chunk into a group chunk with multiple subchunks and:
-    - Add 'optWraparound' to the 'opts' subchunk.
-    - Add 'notl' subchunk.
+  - Convert 'disp' chunk into a group chunk with multiple subchunks and
+    - add 'optWraparound' to the 'opts' subchunk.
+    - add 'notl' subchunk.
 
 
 Version 3

src/actions.nim

@@ -771,15 +771,13 @@ proc resizeLevel*(map; loc: Location, newRows, newCols: Natural,
       levelId = loc.levelId
       l = m.levels[levelId]
 
+    # Propagate ID as this is the same level, just resized
     var newLevel = newLevel(l.locationName, l.levelName, l.elevation,
                             newRows, newCols,
                             l.overrideCoordOpts, l.coordOpts,
                             l.regionOpts,
                             l.notes,
-                            initRegions=false)
-
-    # Propagate ID as this is the same level, just resized
-    newLevel.id = levelId
+                            initRegions=false, overrideId=levelId.some)
 
     newLevel.copyCellsAndAnnotationsFrom(destRow, destCol, l, copyRect)
 
@@ -846,12 +844,10 @@ proc cropLevel*(map; loc: Location, cropRect: Rect[Natural]; um): Location =
                                           newLevelRect, wraparound=false)
 
   let action = proc (m: var Map): UndoStateData =
-    let levelId  = loc.levelId
-    var newLevel = m.newLevelFrom(levelId, cropRect)
+    let levelId = loc.levelId
 
     # Propagate ID as this is the same level, just cropped
-    newLevel.id = levelId
-
+    let newLevel = m.newLevelFrom(levelId, cropRect, overrideId=levelId.some)
     m.setLevel(newLevel)
 
     # Adjust links
@@ -907,18 +903,16 @@ proc nudgeLevel*(map; loc: Location, rowOffs, colOffs: int,
 
   # Do action
   let action = proc (m: var Map): UndoStateData =
+    # Propagate ID as this is the same level, just nudged
     var l = newLevel(
       sb.level.locationName, sb.level.levelName, sb.level.elevation,
       sb.level.rows, sb.level.cols,
       sb.level.overrideCoordOpts, sb.level.coordOpts,
       sb.level.regionOpts,
       sb.level.notes,
-      initRegions=false
+      initRegions=false, overrideId=levelId.some
     )
 
-    # Propagate ID as this is the same level, just nudged
-    l.id = levelId
-
     if wraparound:
       discard l.pasteWithWraparound(destRow=rowOffs, destCol=colOffs,
                                     srcLevel=sb.level, sb.selection,

src/common.nim

@@ -107,7 +107,9 @@ type
     csLetter = 1
 
   Level* = ref object
+    # Internal ID, never written to disk
     id*:                Natural
+
     locationName*:      string
     levelName*:         string
     elevation*:         int
@@ -139,7 +141,9 @@ type
     row*, col*: Natural
 
   Region* = object
+    # Internal ID, never written to disk
     id*:    Natural
+
     name*:  string
     notes*: string
 

src/drawlevel.nim

@@ -2751,13 +2751,15 @@ proc drawLevel*(map: Map, levelId: Natural; ctx) =
           dp.viewStartRow + dp.viewRows,
           dp.viewStartCol + dp.viewCols
         ),
-        border = ViewBufBorder
+        border = ViewBufBorder,
+        overrideId = 0.Natural.some
       )
     else:
       newLevel(
         locationName = "", levelName = "", elevation = 0,
         rows = dp.viewRows + ViewBufBorder*2,
-        cols = dp.viewCols + ViewBufBorder*2
+        cols = dp.viewCols + ViewBufBorder*2,
+        overrideId = 0.Natural.some
       )
 
   assert dp.viewStartRow + dp.viewRows <= l.rows

src/level.nim

@@ -12,9 +12,7 @@ import selection
 
 using l: Level
 
-const
-  # internal ID, never written to disk
-  MoveBufferLevelId* = Natural.high
+const MoveBufferLevelId* = Natural.high
 
 # {{{ CellGrid
 
@@ -309,9 +307,9 @@ proc eraseOrphanedWalls*(l; r,c: Natural) =
 # {{{ eraseCellWalls*()
 proc eraseCellWalls*(l; r,c: Natural) =
   l.setWall(r,c, dirN, wNone)
-  l.setWall(r,c, dirW,  wNone)
+  l.setWall(r,c, dirW, wNone)
   l.setWall(r,c, dirS, wNone)
-  l.setWall(r,c, dirE,  wNone)
+  l.setWall(r,c, dirE, wNone)
 
 # }}}
 # {{{ eraseCell*()
@@ -527,20 +525,24 @@ const DefaultRegionOpts = RegionOptions(
 
 proc newLevel*(locationName, levelName: string, elevation: int,
                rows, cols: Natural,
-               overrideCoordOpts: bool = false,
+               overrideCoordOpts = false,
                coordOpts: CoordinateOptions = DefaultCoordOpts,
                regionOpts: RegionOptions = DefaultRegionOpts,
                notes: string = "",
-               initRegions: bool = true): Level =
+               initRegions = true,
+               overrideId: Option[Natural] = Natural.none): Level =
 
   var l = new Level
 
-  l.id = g_levelIdCounter
-  inc(g_levelIdCounter)
+  if overrideId.isSome:
+    l.id = overrideId.get
+  else:
+    l.id = g_levelIdCounter
+    inc(g_levelIdCounter)
 
   l.locationName = locationName
-  l.levelName = levelName
-  l.elevation = elevation
+  l.levelName    = levelName
+  l.elevation    = elevation
 
   l.overrideCoordOpts = overrideCoordOpts
   l.coordOpts = coordOpts
@@ -565,8 +567,8 @@ proc calcNewLevelFromParams*(
   srcLevel: Level, srcRect: Rect[Natural], border: Natural = 0
 ): tuple[copyRect: Rect[Natural], destRow, destCol: Natural] =
 
-  assert srcRect.r1 < srcLevel.rows
-  assert srcRect.c1 < srcLevel.cols
+  assert srcRect.r1  < srcLevel.rows
+  assert srcRect.c1  < srcLevel.cols
   assert srcRect.r2 <= srcLevel.rows
   assert srcRect.c2 <= srcLevel.cols
 
@@ -601,7 +603,8 @@ proc calcNewLevelFromParams*(
 # NOTE: This method doesn't copy the regions.
 
 proc newLevelFrom*(srcLevel: Level, srcRect: Rect[Natural],
-                   border: Natural = 0): Level =
+                   border: Natural = 0,
+                   overrideId: Option[Natural] = Natural.none): Level =
 
   let (copyRect, destRow, destCol) = calcNewLevelFromParams(srcLevel, srcRect,
                                                             border)
@@ -612,7 +615,8 @@ proc newLevelFrom*(srcLevel: Level, srcRect: Rect[Natural],
     cols = srcRect.cols + border*2,
     srcLevel.overrideCoordOpts, srcLevel.coordOpts, srcLevel.regionOpts,
     srcLevel.notes,
-    initRegions=false
+    initRegions = false,
+    overrideId = overrideId
   )
 
   result.copyCellsAndAnnotationsFrom(destRow, destCol, srcLevel, copyRect)

src/map.nim

@@ -397,12 +397,13 @@ proc calcRegionResizeOffsets*(
 
 # }}}
 
-# {{{ newLevelFrom*()
-proc newLevelFrom*(m; srcLevelId: Natural, srcRect: Rect[Natural]): Level =
+proc newLevelFrom*(m; srcLevelId: Natural, srcRect: Rect[Natural],
+                   overrideId: Option[Natural] = Natural.none): Level =
+
   let src = m.levels[srcLevelId]
   alias(ro, src.regionOpts)
 
-  var dest = newLevelFrom(src, srcRect)
+  var dest = newLevelFrom(src, srcRect, overrideId=overrideId)
 
   # Copy regions
   let (copyRect, _, _) = calcNewLevelFromParams(src, srcRect)