Split WoofWare.PawPrint.Domain into a new subtree (#41)

WoofWare.PawPrint.Domain/MemberReference.fs

@@ -0,0 +1,68 @@
+namespace WoofWare.PawPrint
+
+open System
+open System.Reflection
+open System.Reflection.Metadata
+
+type MemberSignature =
+    | Field of TypeDefn
+    | Method of TypeMethodSignature<TypeDefn>
+
+type MemberReference<'parent> =
+    {
+        Name : StringToken
+        PrettyName : string
+        Parent : 'parent
+        Signature : MemberSignature
+    }
+
+type MemberRefSigSwitch =
+    | Default
+    | Field
+    | VarArg
+    | Generic
+
+    static member Identify (b : byte) =
+        match b &&& 0xFuy with
+        | 0uy -> MemberRefSigSwitch.Default
+        | 5uy -> MemberRefSigSwitch.VarArg
+        | 6uy -> MemberRefSigSwitch.Field
+        | 0x10uy -> MemberRefSigSwitch.Generic
+        | n -> failwith $"Bad member ref sig: %i{n}"
+
+[<RequireQualifiedAccess>]
+module MemberReference =
+    let make<'parent>
+        (blobReader : BlobHandle -> BlobReader)
+        (getString : StringHandle -> string)
+        (makeParent : EntityHandle -> 'parent)
+        (assemblyName : AssemblyName)
+        (mr : System.Reflection.Metadata.MemberReference)
+        : MemberReference<'parent>
+        =
+        let name = StringToken.String mr.Name
+
+        let br = blobReader mr.Signature
+        let header = br.ReadSignatureHeader ()
+
+        let signature =
+            match header.Kind with
+            | SignatureKind.Method -> mr.DecodeMethodSignature (TypeDefn.typeProvider assemblyName, ()) |> Choice1Of2
+            | SignatureKind.Field -> mr.DecodeFieldSignature (TypeDefn.typeProvider assemblyName, ()) |> Choice2Of2
+            | SignatureKind.LocalVariables -> failwith "TODO: LocalVariables"
+            | SignatureKind.Property -> failwith "TODO: Property"
+            | SignatureKind.MethodSpecification -> failwith "TODO: MethodSpec"
+            | i -> raise (ArgumentOutOfRangeException $"{i}")
+
+        let signature =
+            match signature with
+            | Choice1Of2 methodSignature -> TypeMethodSignature.make methodSignature |> MemberSignature.Method
+            | Choice2Of2 typeDefn -> MemberSignature.Field typeDefn
+
+        {
+            Name = name
+            PrettyName = getString mr.Name
+            // Horrible abuse to get this as an int
+            Parent = makeParent mr.Parent
+            Signature = signature
+        }