/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <jni.h>
#include <vector>

#include "common_compiler_test.h"
#include "mirror/art_field-inl.h"
#include "scoped_thread_state_change.h"

namespace art {

class ProxyTest : public CommonCompilerTest {
 public:
  // Generate a proxy class with the given name and interfaces. This is a simplification from what
  // libcore does to fit to our test needs. We do not check for duplicated interfaces or methods and
  // we do not declare exceptions.
  mirror::Class* GenerateProxyClass(ScopedObjectAccess& soa, jobject jclass_loader,
                                    const char* className,
                                    const std::vector<mirror::Class*>& interfaces)
      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
    mirror::Class* javaLangObject = class_linker_->FindSystemClass(soa.Self(), "Ljava/lang/Object;");
    CHECK(javaLangObject != nullptr);

    jclass javaLangClass = soa.AddLocalReference<jclass>(mirror::Class::GetJavaLangClass());

    // Builds the interfaces array.
    jobjectArray proxyClassInterfaces = soa.Env()->NewObjectArray(interfaces.size(), javaLangClass,
                                                                  nullptr);
    soa.Self()->AssertNoPendingException();
    for (size_t i = 0; i < interfaces.size(); ++i) {
      soa.Env()->SetObjectArrayElement(proxyClassInterfaces, i,
                                       soa.AddLocalReference<jclass>(interfaces[i]));
    }

    // Builds the method array.
    jsize methods_count = 3;  // Object.equals, Object.hashCode and Object.toString.
    for (mirror::Class* interface : interfaces) {
      mirror::ObjectArray<mirror::ArtMethod>* virtual_methods = interface->GetVirtualMethods();
      methods_count += (virtual_methods == nullptr) ? 0 : virtual_methods->GetLength();
    }
    jclass javaLangReflectArtMethod =
        soa.AddLocalReference<jclass>(mirror::ArtMethod::GetJavaLangReflectArtMethod());
    jobjectArray proxyClassMethods = soa.Env()->NewObjectArray(methods_count,
                                                               javaLangReflectArtMethod, nullptr);
    soa.Self()->AssertNoPendingException();

    // Fill the method array
    mirror::ArtMethod* equalsMethod = javaLangObject->FindDeclaredVirtualMethod("equals",
                                                                                "(Ljava/lang/Object;)Z");
    mirror::ArtMethod* hashCodeMethod = javaLangObject->FindDeclaredVirtualMethod("hashCode",
                                                                                  "()I");
    mirror::ArtMethod* toStringMethod = javaLangObject->FindDeclaredVirtualMethod("toString",
                                                                                  "()Ljava/lang/String;");
    CHECK(equalsMethod != nullptr);
    CHECK(hashCodeMethod != nullptr);
    CHECK(toStringMethod != nullptr);

    jsize array_index = 0;
    // Adds Object methods.
    soa.Env()->SetObjectArrayElement(proxyClassMethods, array_index++,
                                     soa.AddLocalReference<jobject>(equalsMethod));
    soa.Env()->SetObjectArrayElement(proxyClassMethods, array_index++,
                                     soa.AddLocalReference<jobject>(hashCodeMethod));
    soa.Env()->SetObjectArrayElement(proxyClassMethods, array_index++,
                                     soa.AddLocalReference<jobject>(toStringMethod));

    // Now adds all interfaces virtual methods.
    for (mirror::Class* interface : interfaces) {
      mirror::ObjectArray<mirror::ArtMethod>* virtual_methods = interface->GetVirtualMethods();
      if (virtual_methods != nullptr) {
        for (int32_t mth_index = 0; mth_index < virtual_methods->GetLength(); ++mth_index) {
          mirror::ArtMethod* method = virtual_methods->Get(mth_index);
          soa.Env()->SetObjectArrayElement(proxyClassMethods, array_index++,
                                           soa.AddLocalReference<jobject>(method));
        }
      }
    }
    CHECK_EQ(array_index, methods_count);

    // Builds an empty exception array.
    jobjectArray proxyClassThrows = soa.Env()->NewObjectArray(0, javaLangClass, nullptr);
    soa.Self()->AssertNoPendingException();

    mirror::Class* proxyClass = class_linker_->CreateProxyClass(soa,
                                                                soa.Env()->NewStringUTF(className),
                                                                proxyClassInterfaces, jclass_loader,
                                                                proxyClassMethods, proxyClassThrows);
    soa.Self()->AssertNoPendingException();
    return proxyClass;
  }
};

// Creates a proxy class and check ClassHelper works correctly.
TEST_F(ProxyTest, ProxyClassHelper) {
  ScopedObjectAccess soa(Thread::Current());
  jobject jclass_loader = LoadDex("Interfaces");
  StackHandleScope<4> hs(soa.Self());
  Handle<mirror::ClassLoader> class_loader(
      hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));

  Handle<mirror::Class> I(hs.NewHandle(
      class_linker_->FindClass(soa.Self(), "LInterfaces$I;", class_loader)));
  Handle<mirror::Class> J(hs.NewHandle(
      class_linker_->FindClass(soa.Self(), "LInterfaces$J;", class_loader)));
  ASSERT_TRUE(I.Get() != nullptr);
  ASSERT_TRUE(J.Get() != nullptr);

  std::vector<mirror::Class*> interfaces;
  interfaces.push_back(I.Get());
  interfaces.push_back(J.Get());
  Handle<mirror::Class> proxy_class(hs.NewHandle(
      GenerateProxyClass(soa, jclass_loader, "$Proxy1234", interfaces)));
  interfaces.clear();  // Don't least possibly stale objects in the array as good practice.
  ASSERT_TRUE(proxy_class.Get() != nullptr);
  ASSERT_TRUE(proxy_class->IsProxyClass());
  ASSERT_TRUE(proxy_class->IsInitialized());

  EXPECT_EQ(2U, proxy_class->NumDirectInterfaces());  // Interfaces$I and Interfaces$J.
  EXPECT_EQ(I.Get(), mirror::Class::GetDirectInterface(soa.Self(), proxy_class, 0));
  EXPECT_EQ(J.Get(), mirror::Class::GetDirectInterface(soa.Self(), proxy_class, 1));
  std::string proxy_class_descriptor(proxy_class->GetDescriptor());
  EXPECT_STREQ("L$Proxy1234;", proxy_class_descriptor.c_str());
  EXPECT_EQ(nullptr, proxy_class->GetSourceFile());
}

// Creates a proxy class and check FieldHelper works correctly.
TEST_F(ProxyTest, ProxyFieldHelper) {
  ScopedObjectAccess soa(Thread::Current());
  jobject jclass_loader = LoadDex("Interfaces");
  StackHandleScope<9> hs(soa.Self());
  Handle<mirror::ClassLoader> class_loader(
      hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));

  Handle<mirror::Class> I(hs.NewHandle(
      class_linker_->FindClass(soa.Self(), "LInterfaces$I;", class_loader)));
  Handle<mirror::Class> J(hs.NewHandle(
      class_linker_->FindClass(soa.Self(), "LInterfaces$J;", class_loader)));
  ASSERT_TRUE(I.Get() != nullptr);
  ASSERT_TRUE(J.Get() != nullptr);

  Handle<mirror::Class> proxyClass;
  {
    std::vector<mirror::Class*> interfaces;
    interfaces.push_back(I.Get());
    interfaces.push_back(J.Get());
    proxyClass = hs.NewHandle(GenerateProxyClass(soa, jclass_loader, "$Proxy1234", interfaces));
  }

  ASSERT_TRUE(proxyClass.Get() != nullptr);
  ASSERT_TRUE(proxyClass->IsProxyClass());
  ASSERT_TRUE(proxyClass->IsInitialized());

  Handle<mirror::ObjectArray<mirror::ArtField>> instance_fields(
      hs.NewHandle(proxyClass->GetIFields()));
  EXPECT_TRUE(instance_fields.Get() == nullptr);

  Handle<mirror::ObjectArray<mirror::ArtField>> static_fields(
      hs.NewHandle(proxyClass->GetSFields()));
  ASSERT_TRUE(static_fields.Get() != nullptr);
  ASSERT_EQ(2, static_fields->GetLength());

  Handle<mirror::Class> interfacesFieldClass(
      hs.NewHandle(class_linker_->FindSystemClass(soa.Self(), "[Ljava/lang/Class;")));
  ASSERT_TRUE(interfacesFieldClass.Get() != nullptr);
  Handle<mirror::Class> throwsFieldClass(
      hs.NewHandle(class_linker_->FindSystemClass(soa.Self(), "[[Ljava/lang/Class;")));
  ASSERT_TRUE(throwsFieldClass.Get() != nullptr);

  // Test "Class[] interfaces" field.
  FieldHelper fh(hs.NewHandle(static_fields->Get(0)));
  EXPECT_EQ("interfaces", std::string(fh.GetField()->GetName()));
  EXPECT_EQ("[Ljava/lang/Class;", std::string(fh.GetField()->GetTypeDescriptor()));
  EXPECT_EQ(interfacesFieldClass.Get(), fh.GetType());
  EXPECT_EQ("L$Proxy1234;", std::string(fh.GetDeclaringClassDescriptor()));
  EXPECT_FALSE(fh.GetField()->IsPrimitiveType());

  // Test "Class[][] throws" field.
  fh.ChangeField(static_fields->Get(1));
  EXPECT_EQ("throws", std::string(fh.GetField()->GetName()));
  EXPECT_EQ("[[Ljava/lang/Class;", std::string(fh.GetField()->GetTypeDescriptor()));
  EXPECT_EQ(throwsFieldClass.Get(), fh.GetType());
  EXPECT_EQ("L$Proxy1234;", std::string(fh.GetDeclaringClassDescriptor()));
  EXPECT_FALSE(fh.GetField()->IsPrimitiveType());
}

}  // namespace art