Parse the fieldPortal section of table/FieldMetaData.xml

Maple2.File.Parser/Maple2.File.Parser.csproj

@@ -13,7 +13,7 @@
         <PackageTags>MapleStory2, File, Parser, m2d, xml</PackageTags>
         <!-- Use following lines to write the generated files to disk. -->
         <EmitCompilerGeneratedFiles Condition=" '$(Configuration)' == 'Debug' ">true</EmitCompilerGeneratedFiles>
-        <PackageVersion>2.4.22</PackageVersion>
+        <PackageVersion>2.4.23</PackageVersion>
         <TargetFramework>net8.0</TargetFramework>
         <PackageReadmeFile>README.md</PackageReadmeFile>
         <ImplicitUsings>enable</ImplicitUsings>

Maple2.File.Parser/TableParser.cs

@@ -96,6 +96,7 @@ public class TableParser {
     private readonly XmlSerializer blackMarketSerializer;
     private readonly XmlSerializer changeJobSerializer;
     private readonly XmlSerializer fieldMissionSerializer;
+    private readonly XmlSerializer fieldMetaDataSerializer;
     private readonly XmlSerializer worldMapSerializer;
     private readonly XmlSerializer mapleSurvivalSkinInfoSerializer;
     private readonly XmlSerializer weddingExpSerializer;
@@ -212,6 +213,7 @@ public TableParser(M2dReader xmlReader, string language) {
         blackMarketSerializer = new XmlSerializer(typeof(BlackMarketRoot));
         changeJobSerializer = new XmlSerializer(typeof(ChangeJobRoot));
         fieldMissionSerializer = new XmlSerializer(typeof(FieldMissionRoot));
+        fieldMetaDataSerializer = new XmlSerializer(typeof(FieldMetaDataRoot));
         worldMapSerializer = new XmlSerializer(typeof(WorldMapRoot));
         mapleSurvivalSkinInfoSerializer = new XmlSerializer(typeof(MapleSurvivalSkinInfoRoot));
         weddingExpSerializer = new XmlSerializer(typeof(WeddingExpRoot));
@@ -1405,6 +1407,17 @@ public IEnumerable<JobTableNew> ParseJobTableNew() {
         }
     }
 
+    public IEnumerable<(int Id, FieldPortal Portal)> ParseFieldMetaData() {
+        string xml = Sanitizer.RemoveEmpty(xmlReader.GetString(xmlReader.GetEntry($"table/{locale}/fieldmetadata.xml")));
+        var reader = XmlReader.Create(new StringReader(xml));
+        var data = fieldMetaDataSerializer.Deserialize(reader) as FieldMetaDataRoot;
+        Debug.Assert(data != null);
+
+        foreach (FieldPortal entry in data.fieldPortal) {
+            yield return (entry.field, entry);
+        }
+    }
+
     public IEnumerable<(string Feature, IList<WorldMap.Map> Maps)> ParseWorldMap() {
         string xml = Sanitizer.RemoveEmpty(xmlReader.GetString(xmlReader.GetEntry($"table/{locale}/newworldmap.xml")));
         var reader = XmlReader.Create(new StringReader(xml));

Maple2.File.Parser/Xml/Table/FieldMetaData.cs

@@ -0,0 +1,31 @@
+using System.Xml.Serialization;
+using M2dXmlGenerator;
+
+namespace Maple2.File.Parser.Xml.Table;
+
+// ./data/xml/table/na/fieldmetadata.xml
+//
+// Only the <fieldPortal> section is modelled. The file also carries <npc>, <interactObject>,
+// <fluid>, <liftable>, <pet> and <taxiStation> sections, which nothing consumes yet.
+[XmlRoot("ms2")]
+public partial class FieldMetaDataRoot {
+    [M2dFeatureLocale(Selector = "field")] private IList<FieldPortal> _fieldPortal;
+}
+
+// The client builds its sub-map to exploration-zone table from these entries: portals with
+// portalIndoor != 0 are edges, and every map reachable from an indoor="0" entry belongs to
+// that outdoor field. See PrivateMaple2 docs/client-re/field-mission-binding.md.
+public partial class FieldPortal : IFeatureLocale {
+    [XmlAttribute] public int field;
+    [XmlAttribute] public bool indoor;
+    [XmlElement] public List<Portal> portal = new();
+
+    // <portal id="17" targetField="2000025" targetPortal="1" portalType="0" portalIndoor="1" />
+    public partial class Portal {
+        [XmlAttribute] public int id;
+        [XmlAttribute] public int targetField;
+        [XmlAttribute] public int targetPortal;
+        [XmlAttribute] public int portalType;
+        [XmlAttribute] public bool portalIndoor;
+    }
+}

Maple2.File.Tests/TableParserTest.cs

@@ -649,6 +649,32 @@ public void TestFieldMission() {
         }
     }
 
+    // fieldPortal is the client's sub-map to exploration-zone source. The counts and the
+    // Turtcoli Cave edge are what PrivateMaple2 ingests into FieldPortalZoneTable, so a
+    // parse that silently drops portalIndoor or indoor would change server behaviour.
+    [TestMethod]
+    public void TestFieldMetaData() {
+        Dictionary<int, FieldPortal> entries = _parser.ParseFieldMetaData()
+            .ToDictionary(result => result.Id, result => result.Portal);
+
+        Assert.AreEqual(1008, entries.Count);
+        Assert.AreEqual(299, entries.Values.Count(entry => !entry.indoor));
+
+        // Turtcoli Cave reaches Royal Road Plaza through a portalIndoor edge (PrivateMaple2 #388).
+        Assert.IsTrue(entries.TryGetValue(2000250, out FieldPortal? cave));
+        Assert.IsNotNull(cave);
+        Assert.IsTrue(cave.indoor);
+        Assert.IsTrue(cave.portal.Any(portal => portal.targetField == 2000114 && portal.portalIndoor));
+
+        // The PvP arena's portals all target field 0, so it joins no component.
+        Assert.IsTrue(entries.TryGetValue(65010004, out FieldPortal? arena));
+        Assert.IsNotNull(arena);
+        Assert.IsTrue(arena.portal.All(portal => portal.targetField == 0));
+
+        // Wedding Village has no entry at all and never remaps.
+        Assert.IsFalse(entries.ContainsKey(84000001));
+    }
+
     [TestMethod]
     public void TestWorldMap() {
         foreach ((_, _) in _parser.ParseWorldMap()) {