Add transformation pass to C# backend

3 files changed, 89 insertions, 65 deletions

diff --git a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpCodeGenerator.java b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpCodeGenerator.java
new file mode 100644
index 0000000..9e48e9a
--- /dev/null
+++ b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpCodeGenerator.java
@@ -0,0 +1,68 @@
+package org.zwobble.couscous.backends.csharp;
+
+import com.google.common.collect.ImmutableMap;
+import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.visitors.NodeTransformer;
+import org.zwobble.couscous.values.*;
+
+import java.util.Map;
+import java.util.Optional;
+
+public class CsharpCodeGenerator extends NodeTransformer {
+    private final static Map<TypeName, TypeName> PRIMITIVES = ImmutableMap.<TypeName, TypeName>builder()
+        .put(IntegerValue.REF, TypeName.of("int"))
+        .put(StringValue.REF, TypeName.of("string"))
+        .put(BooleanValue.REF, TypeName.of("bool"))
+        .put(ObjectValues.OBJECT, TypeName.of("object"))
+        .put(ObjectValues.CLASS, TypeName.of("System.Type"))
+        .put(UnitValue.REF, TypeName.of("void"))
+        .build();
+
+    private final String namespace;
+
+    public static Node generateCode(Node node, String namespace) {
+        return new CsharpCodeGenerator(namespace).generateCode(node);
+    }
+
+    private CsharpCodeGenerator(String namespace) {
+        this.namespace = namespace;
+    }
+
+    private Node generateCode(Node node) {
+        return node.accept(this);
+    }
+
+    @Override
+    public TypeName transform(TypeName type) {
+        if (PRIMITIVES.containsKey(type)) {
+            return PRIMITIVES.get(type);
+        } else {
+            return addPrefix(type, namespace);
+        }
+    }
+
+    @Override
+    public ExpressionNode visit(MethodCallNode call) {
+        return toPrimitiveMethod(call).orElseGet(() -> super.visit(call));
+    }
+
+    private Optional<ExpressionNode> toPrimitiveMethod(MethodCallNode call) {
+        return call.getReceiver().accept(new Receiver.Mapper<Optional<ExpressionNode>>() {
+            @Override
+            public Optional<ExpressionNode> visit(ExpressionNode receiver) {
+                return Optional.empty();
+            }
+
+            @Override
+            public Optional<ExpressionNode> visit(TypeName receiver) {
+                return CsharpPrimitiveMethods.getPrimitiveStaticMethod(receiver, call.getMethodName())
+                    .map(generator -> generator.generate(call.getArguments()));
+            }
+        });
+
+    }
+
+    private TypeName addPrefix(TypeName name, String namespace) {
+        return TypeName.of(namespace + "." + name.getQualifiedName());
+    }
+}
diff --git a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpPrimitiveMethods.java b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpPrimitiveMethods.java
index b53560d..9424b2d 100644
--- a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpPrimitiveMethods.java
+++ b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpPrimitiveMethods.java
@@ -3,25 +3,24 @@ package org.zwobble.couscous.backends.csharp;
 import com.google.common.collect.ImmutableMap;
 import org.zwobble.couscous.ast.ExpressionNode;
 import org.zwobble.couscous.ast.TypeName;
-import org.zwobble.couscous.backends.SourceCodeWriter;
 import org.zwobble.couscous.values.ObjectValues;
 
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
+import static org.zwobble.couscous.ast.MethodCallNode.staticMethodCall;
+import static org.zwobble.couscous.util.ExtraLists.list;
+
 public class CsharpPrimitiveMethods {
     private static final Map<String, PrimitiveStaticMethodGenerator> STATIC_INT_METHODS =
         ImmutableMap.<String, PrimitiveStaticMethodGenerator>builder()
 
-            .put("parseInt", (arguments, writer) -> {
-                writer.writeIdentifier("int");
-                writer.writeSymbol(".");
-                writer.writeIdentifier("Parse");
-                writer.writeSymbol("(");
-                writer.writeIdentifier(CsharpSerializer.serialize(arguments.get(0), ""));
-                writer.writeSymbol(")");
-            })
+            .put("parseInt", arguments -> staticMethodCall(
+                TypeName.of("int"),
+                "Parse",
+                list(arguments.get(0)),
+                TypeName.of("int")))
 
             .build();
 
@@ -37,6 +36,6 @@ public class CsharpPrimitiveMethods {
 
     @FunctionalInterface
     public interface PrimitiveStaticMethodGenerator {
-        void generate(List<ExpressionNode> arguments, SourceCodeWriter writer);
+        ExpressionNode generate(List<ExpressionNode> arguments);
     }
 }
diff --git a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpSerializer.java b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpSerializer.java
index 275ae13..ffd2f02 100644
--- a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpSerializer.java
+++ b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpSerializer.java
@@ -1,24 +1,13 @@
 package org.zwobble.couscous.backends.csharp;
 
-import com.google.common.collect.ImmutableMap;
 import org.zwobble.couscous.ast.*;
 import org.zwobble.couscous.ast.visitors.NodeVisitor;
 import org.zwobble.couscous.backends.SourceCodeWriter;
-import org.zwobble.couscous.values.*;
+import org.zwobble.couscous.values.PrimitiveValueVisitor;
 
 import java.util.List;
-import java.util.Map;
 
 public class CsharpSerializer implements NodeVisitor {
-    private final static Map<TypeName, String> PRIMITIVES = ImmutableMap.<TypeName, String>builder()
-        .put(IntegerValue.REF, "int")
-        .put(StringValue.REF, "string")
-        .put(BooleanValue.REF, "bool")
-        .put(ObjectValues.OBJECT, "object")
-        .put(ObjectValues.CLASS, "System.Type")
-        .put(UnitValue.REF, "void")
-        .build();
-
     public static String serialize(Node node, String namespace) {
         SourceCodeWriter writer = new SourceCodeWriter(
             (writer2) -> {
@@ -29,17 +18,16 @@ public class CsharpSerializer implements NodeVisitor {
                 writer2.writeStatement(() -> writer2.writeSymbol("}"));
             }
         );
-        CsharpSerializer serializer = new CsharpSerializer(writer, namespace);
-        serializer.write(node);
+        CsharpSerializer serializer = new CsharpSerializer(writer);
+
+        serializer.write(CsharpCodeGenerator.generateCode(node, namespace));
         return writer.asString();
     }
 
     private final SourceCodeWriter writer;
-    private final String namespace;
 
-    private CsharpSerializer(SourceCodeWriter writer, String namespace) {
+    private CsharpSerializer(SourceCodeWriter writer) {
         this.writer = writer;
-        this.namespace = namespace;
     }
 
     private void write(Node node) {
@@ -117,32 +105,10 @@ public class CsharpSerializer implements NodeVisitor {
 
     @Override
     public void visit(MethodCallNode methodCall) {
-        if (!writePrimitiveMethod(methodCall)) {
-            write(methodCall.getReceiver());
-            writer.writeSymbol(".");
-            writer.writeIdentifier(methodCall.getMethodName());
-            writeArguments(methodCall.getArguments());
-        }
-    }
-
-    private boolean writePrimitiveMethod(MethodCallNode methodCall) {
-        return methodCall.getReceiver().accept(new Receiver.Mapper<Boolean>() {
-            @Override
-            public Boolean visit(ExpressionNode receiver) {
-                return false;
-            }
-
-            @Override
-            public Boolean visit(TypeName receiver) {
-                // TODO: transform AST before serialisation instead of exposing write to CsharpPrimitiveMethods
-                return CsharpPrimitiveMethods.getPrimitiveStaticMethod(receiver, methodCall.getMethodName())
-                    .map(generator -> {
-                        generator.generate(methodCall.getArguments(), writer);
-                        return true;
-                    })
-                    .orElse(false);
-            }
-        });
+        write(methodCall.getReceiver());
+        writer.writeSymbol(".");
+        writer.writeIdentifier(methodCall.getMethodName());
+        writeArguments(methodCall.getArguments());
     }
 
     @Override
@@ -278,13 +244,9 @@ public class CsharpSerializer implements NodeVisitor {
 
     @Override
     public void visit(ClassNode classNode) {
-        String namespace = this.namespace +
-            classNode.getName().getPackage()
-                .map(packageName -> "." + packageName)
-                .orElse("");
         writer.writeKeyword("namespace");
         writer.writeSpace();
-        writer.writeIdentifier(namespace);
+        writer.writeIdentifier(classNode.getName().getPackage().get());
         writer.startBlock();
         writer.writeStatement(() -> {
             writer.writeKeyword("internal");
@@ -323,15 +285,10 @@ public class CsharpSerializer implements NodeVisitor {
     }
 
     private void writeTypeReference(TypeName value) {
-        // TODO: process the nodes before serialization
-        if (PRIMITIVES.containsKey(value)) {
-            writer.writeIdentifier(PRIMITIVES.get(value));
-        } else {
-            writer.writeIdentifier(typeReference(value));
-        }
+        writer.writeIdentifier(typeReference(value));
     }
 
     private String typeReference(TypeName value) {
-        return namespace + "." + value.getQualifiedName();
+        return value.getQualifiedName();
     }
 }