Schematic content ID mapping

core/src/mindustry/game/Schematics.java

@@ -25,6 +25,7 @@ import mindustry.gen.*;
 import mindustry.input.*;
 import mindustry.input.Placement.*;
 import mindustry.io.*;
+import mindustry.io.TypeIO.*;
 import mindustry.world.*;
 import mindustry.world.blocks.ConstructBlock.*;
 import mindustry.world.blocks.distribution.*;
@@ -539,6 +540,8 @@ public class Schematics implements Loadable{
 
         int ver = input.read();
 
+        if(ver > version) throw new IOException("Unknown version: " + ver + " (are you trying to load a schematic from a newer version of the game?)");
+
         try(DataInputStream stream = new DataInputStream(new InflaterInputStream(input))){
             short width = stream.readShort(), height = stream.readShort();
 
@@ -550,13 +553,28 @@ public class Schematics implements Loadable{
                 map.put(stream.readUTF(), stream.readUTF());
             }
 
+            ContentMapper mapper = null;
+
+            //set up content mapping if found; this should not fail
+            if(map.containsKey("contentMap")){
+                IntMap<ObjectIntMap<String>> nameMap = JsonIO.json.fromJson(IntMap.class, ObjectIntMap.class, map.get("contentMap", "{}"));
+                IntMap<IntMap<Content>> contentMap = new IntMap<>();
+                for(var entry : nameMap){
+                    var inner = new IntMap<Content>();
+                    contentMap.put(entry.key, inner);
+                    for(var ce : entry.value){
+                        inner.put(ce.value, content.getByName(ContentType.all[entry.key], ce.key));
+                    }
+                }
+                mapper = (type, id) -> contentMap.get(type.ordinal(), IntMap::new).get(id);
+            }
+
             String[] labels = null;
 
             //try to read the categories, but skip if it fails
             try{
                 labels = JsonIO.read(String[].class, map.get("labels", "[]"));
-            }catch(Exception ignored){
-            }
+            }catch(Exception ignored){}
 
             IntMap<Block> blocks = new IntMap<>();
             int length = stream.readUnsignedByte();
@@ -574,7 +592,7 @@ public class Schematics implements Loadable{
             for(int i = 0; i < total; i++){
                 Block block = blocks.get(stream.readByte());
                 int position = stream.readInt();
-                Object config = ver == 0 ? mapConfig(block, stream.readInt(), position) : TypeIO.readObject(Reads.get(stream));
+                Object config = ver == 0 ? mapConfig(block, stream.readInt(), position) : TypeIO.readObject(Reads.get(stream), false, mapper);
                 byte rotation = stream.readByte();
                 if(block != Blocks.air){
                     tiles.add(new Stile(block, Point2.x(position), Point2.y(position), config, rotation));
@@ -602,6 +620,16 @@ public class Schematics implements Loadable{
 
             schematic.tags.put("labels", JsonIO.write(schematic.labels.toArray(String.class)));
 
+            //write a map for content name -> id to make sure remapping doesn't occur
+            IntMap<ObjectIntMap<String>> contentMap = new IntMap<>();
+            for(var tile : schematic.tiles){
+                if(tile.config instanceof MappableContent c){
+                    contentMap.get(c.getContentType().ordinal(), ObjectIntMap::new).put(c.name, c.id);
+                }
+            }
+
+            schematic.tags.put("contentMap", JsonIO.write(contentMap));
+
             stream.writeByte(schematic.tags.size);
             for(var e : schematic.tags.entries()){
                 stream.writeUTF(e.key);

core/src/mindustry/io/TypeIO.java

@@ -138,14 +138,16 @@ public class TypeIO{
         }
     }
 
-    @Nullable
-    public static Object readObject(Reads read){
+    public static @Nullable Object readObject(Reads read){
         return readObjectBoxed(read, false);
     }
 
-    /** Reads an object, but boxes buildings. */
-    @Nullable
-    public static Object readObjectBoxed(Reads read, boolean box){
+    /** Reads an object, but optionally boxes buildings. */
+    public static @Nullable Object readObjectBoxed(Reads read, boolean box){
+        return readObject(read, box, null);
+    }
+
+    public static @Nullable Object readObject(Reads read, boolean box, @Nullable ContentMapper mapper){
         byte type = read.b();
         return switch(type){
             case 0 -> null;
@@ -153,7 +155,7 @@ public class TypeIO{
             case 2 -> read.l();
             case 3 -> read.f();
             case 4 -> readString(read);
-            case 5 -> content.getByID(ContentType.all[read.b()], read.s());
+            case 5 -> mapper == null ? content.getByID(ContentType.all[read.b()], read.s()) : mapper.get(ContentType.all[read.b()], read.s());
             case 6 -> {
                 short length = read.s();
                 IntSeq arr = new IntSeq(length);
@@ -202,7 +204,7 @@ public class TypeIO{
             case 22 -> {
                 int objlen = read.i();
                 Object[] objs = new Object[objlen];
-                for(int i = 0; i < objlen; i++) objs[i] = readObjectBoxed(read, box);
+                for(int i = 0; i < objlen; i++) objs[i] = readObject(read, box, mapper);
                 yield objs;
             }
             case 23 -> content.unitCommand(read.us());
@@ -1093,6 +1095,11 @@ public class TypeIO{
         }
     }
 
+    /** Converter of an ID to a content instance. */
+    public interface ContentMapper{
+        Content get(ContentType type, int id);
+    }
+
     public interface Boxed<T> {
         T unbox();
     }