Initial sync

Nbt/Tag/NbtTag.cs

@@ -0,0 +1,68 @@
+namespace Nbt.Tag;
+
+public interface INbtTag : IEquatable<INbtTag>
+{
+    NbtTagType Type { get; }
+
+    INbtTag this[string tagName] { get => throw new NotSupportedException(); set => throw new NotSupportedException(); }
+
+    INbtTag this[int tagIndex] { get => throw new NotSupportedException(); set => throw new NotSupportedException(); }
+
+    INbtTag this[INbtPathElement tagPath] { get => throw new NotSupportedException(); set => throw new NotSupportedException(); }
+
+    INbtTag this[INbtPath tagPath]
+    {
+        get
+        {
+            var count = tagPath.Count;
+
+            if (count == 0)
+            {
+                return this;
+            }
+
+            var pathElt = tagPath.PopFirst(out var pathRest);
+            var childTag = this[pathElt];
+
+            return childTag[pathRest];
+        }
+
+        set
+        {
+            var count = tagPath.Count;
+
+            if (count == 0)
+            {
+                throw new ArgumentException("Path cannot be empty", nameof(value));
+            }
+
+            var pathElt = tagPath.PopFirst(out var pathRest);
+
+            if (count == 1)
+            {
+                this[pathElt] = value;
+            }
+            else
+            {
+                var childTag = this[pathElt];
+                childTag[pathRest] = value;
+            }
+        }
+    }
+
+    INbtList AsList() => (INbtList)this;
+
+    INbtCompound AsCompound() => (INbtCompound)this;
+
+    INbtValue AsValue() => (INbtValue)this;
+
+    INbtValue<T> AsValue<T>() where T : notnull => (INbtValue<T>)this;
+
+    INbtArray AsArray() => (INbtArray)this;
+
+    INbtArray<T> AsArray<T>() where T : notnull => (INbtArray<T>)this;
+
+    T As<T>() where T : INbtTag => (T)this;
+
+    INbtTag Copy();
+}