/*
 * Copyright (C) 2012 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.
 */

package com.android.dx.mockito;

import com.android.dx.stock.ProxyBuilder;
import org.mockito.internal.debugging.LocationImpl;
import org.mockito.internal.invocation.InvocationImpl;
import org.mockito.internal.invocation.MockitoMethod;
import org.mockito.internal.invocation.realmethod.RealMethod;
import org.mockito.internal.progress.SequenceNumber;
import org.mockito.invocation.MockHandler;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

/**
 * Handles proxy method invocations to dexmaker's InvocationHandler by calling
 * a MockitoInvocationHandler.
 */
final class InvocationHandlerAdapter implements InvocationHandler {
    private MockHandler handler;

    public InvocationHandlerAdapter(MockHandler handler) {
        this.handler = handler;
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        // args can be null if the method invoked has no arguments, but Mockito expects a non-null array
        args = args != null ? args : new Object[0];
        if (isEqualsMethod(method)) {
            return proxy == args[0];
        } else if (isHashCodeMethod(method)) {
            return System.identityHashCode(proxy);
        }

        ProxiedMethod proxiedMethod = new ProxiedMethod(method);
        return handler.handle(new InvocationImpl(proxy, proxiedMethod, args, SequenceNumber.next(),
                proxiedMethod, new LocationImpl()));
    }

    public MockHandler getHandler() {
        return handler;
    }

    public void setHandler(MockHandler handler) {
        this.handler = handler;
    }

    private static boolean isEqualsMethod(Method method) {
        return method.getName().equals("equals")
                && method.getParameterTypes().length == 1
                && method.getParameterTypes()[0] == Object.class;
    }

    private static boolean isHashCodeMethod(Method method) {
        return method.getName().equals("hashCode")
                && method.getParameterTypes().length == 0;
    }

    private static class ProxiedMethod implements MockitoMethod, RealMethod {
        private final Method method;

        ProxiedMethod(Method method) {
            this.method = method;
        }

        @Override
        public String getName() {
            return method.getName();
        }

        @Override
        public Class<?> getReturnType() {
            return method.getReturnType();
        }

        @Override
        public Class<?>[] getParameterTypes() {
            return method.getParameterTypes();
        }

        @Override
        public Class<?>[] getExceptionTypes() {
            return method.getExceptionTypes();
        }

        @Override
        public boolean isVarArgs() {
            return method.isVarArgs();
        }

        @Override
        public Method getJavaMethod() {
            return method;
        }

        @Override
        public Object invoke(Object target, Object[] arguments) throws Throwable {
            return ProxyBuilder.callSuper(target, method, arguments);
        }

        @Override
        public boolean isAbstract() {
            return Modifier.isAbstract(method.getModifiers());
        }
    }
}