/*
    * MIT License
    * Copyright (c) 2006-2025 JMockit developers
    * See LICENSE file for full license text.
    */
   package mockit.internal.faking;
   
   import static java.lang.reflect.Modifier.isPublic;
   
  import edu.umd.cs.findbugs.annotations.NonNull;
  import edu.umd.cs.findbugs.annotations.Nullable;
  
  import java.lang.reflect.Proxy;
  import java.lang.reflect.Type;
  
  import mockit.MockUp;
  import mockit.asm.classes.ClassReader;
  import mockit.asm.classes.ClassVisitor;
  import mockit.internal.classGeneration.ImplementationClass;
  import mockit.internal.expectations.mocking.InterfaceImplementationGenerator;
  import mockit.internal.util.Utilities;
  
  public final class FakedImplementationClass<T> {
      private static final ClassLoader THIS_CL = FakedImplementationClass.class.getClassLoader();
  
      @NonNull
      private final MockUp<?> fakeInstance;
      @Nullable
      private ImplementationClass<T> implementationClass;
      private Class<T> generatedClass;
  
      public FakedImplementationClass(@NonNull MockUp<?> fakeInstance) {
          this.fakeInstance = fakeInstance;
      }
  
      @NonNull
      public Class<T> createImplementation(@NonNull Class<T> interfaceToBeFaked, @Nullable Type typeToFake) {
          createImplementation(interfaceToBeFaked);
          byte[] generatedBytecode = implementationClass == null ? null : implementationClass.getGeneratedBytecode();
  
          FakeClassSetup fakeClassSetup = new FakeClassSetup(generatedClass, typeToFake, fakeInstance, generatedBytecode);
          fakeClassSetup.redefineMethodsInGeneratedClass();
  
          return generatedClass;
      }
  
      @NonNull
      Class<T> createImplementation(@NonNull Class<T> interfaceToBeFaked) {
          if (isPublic(interfaceToBeFaked.getModifiers())) {
              generateImplementationForPublicInterface(interfaceToBeFaked);
          } else {
              // noinspection unchecked
              generatedClass = (Class<T>) Proxy.getProxyClass(interfaceToBeFaked.getClassLoader(), interfaceToBeFaked);
          }
  
          return generatedClass;
      }
  
      private void generateImplementationForPublicInterface(@NonNull Class<T> interfaceToBeFaked) {
          implementationClass = new ImplementationClass<T>(interfaceToBeFaked) {
              @NonNull
              @Override
              protected ClassVisitor createMethodBodyGenerator(@NonNull ClassReader typeReader) {
                  return new InterfaceImplementationGenerator(typeReader, interfaceToBeFaked, generatedClassName);
              }
          };
  
          generatedClass = implementationClass.generateClass();
      }
  
      @NonNull
      public Class<T> createImplementation(@NonNull Type[] interfacesToBeFaked) {
          Class<?>[] interfacesToFake = new Class<?>[interfacesToBeFaked.length];
  
          for (int i = 0; i < interfacesToFake.length; i++) {
              interfacesToFake[i] = Utilities.getClassType(interfacesToBeFaked[i]);
          }
  
          // noinspection unchecked
          generatedClass = (Class<T>) Proxy.getProxyClass(THIS_CL, interfacesToFake);
          new FakeClassSetup(generatedClass, null, fakeInstance, null).redefineMethods();
  
          return generatedClass;
      }
  }