/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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 org.codehaus.groovy.runtime.callsite;

import groovy.lang.GroovyRuntimeException;
import groovy.lang.MetaClassImpl;
import groovy.lang.MetaMethod;
import org.codehaus.groovy.reflection.CachedMethod;
import org.codehaus.groovy.runtime.GroovyCategorySupport;
import org.codehaus.groovy.runtime.MetaClassHelper;
import org.codehaus.groovy.runtime.NullObject;
import org.codehaus.groovy.runtime.ScriptBytecodeAdapter;

import java.lang.reflect.Method;

/**
 * POJO call site
 *   meta class - cached
 *   method - cached
 *
 * @author Alex Tkachman
*/
public class PojoMetaMethodSite extends PlainObjectMetaMethodSite {

    protected final int version;

    public PojoMetaMethodSite(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class params[]) {
        super(site, metaClass, metaMethod, params);
        version = metaClass.getVersion();
    }

    public Object invoke(Object receiver, Object[] args) throws Throwable {
        MetaClassHelper.unwrap(args);
        return metaMethod.doMethodInvoke(receiver,  args);
    }

    public Object call(Object receiver, Object[] args) throws Throwable {
        if(checkCall(receiver, args))
          return invoke(receiver,args);
        else
          return CallSiteArray.defaultCall(this, receiver, args);
    }

    protected final boolean checkPojoMetaClass() {
        return !GroovyCategorySupport.hasCategoryInCurrentThread()
            && ((MetaClassImpl)metaClass).getVersion() == version;
    }

    protected final boolean checkCall(Object receiver, Object[] args) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params, args);
        }
        catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject(), args);

            throw e;
        }
    }

    protected final boolean checkCall(Object receiver) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params);
        } catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject());

            throw e;
        }
    }

    protected final boolean checkCall(Object receiver, Object arg1) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params, arg1);
        } catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject(), arg1);

            throw e;
        }
    }

    protected final boolean checkCall(Object receiver, Object arg1, Object arg2) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params, arg1, arg2);
        } catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject(), arg1, arg2);

            throw e;
        }
    }

    protected final boolean checkCall(Object receiver, Object arg1, Object arg2, Object arg3) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params, arg1, arg2, arg3);
        } catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject(), arg1, arg2, arg3);

            throw e;
        }
    }

    protected final boolean checkCall(Object receiver, Object arg1, Object arg2, Object arg3, Object arg4) {
        try {
            return receiver.getClass() == metaClass.getTheClass() // meta class match receiver
               && checkPojoMetaClass()
               && MetaClassHelper.sameClasses(params, arg1, arg2, arg3, arg4);
        } catch (NullPointerException e) {
            if (receiver == null)
              return checkCall(NullObject.getNullObject(), arg1, arg2, arg3, arg4);

            throw e;
        }
    }

    public static CallSite createPojoMetaMethodSite(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class[] params, Object receiver, Object[] args) {
        if (metaMethod instanceof CallSiteAwareMetaMethod) {
            return ((CallSiteAwareMetaMethod)metaMethod).createPojoCallSite(site, metaClass, metaMethod, params, receiver, args);
        }

        if (metaMethod.getClass() == CachedMethod.class)
          return createCachedMethodSite (site, metaClass, (CachedMethod) metaMethod, params, args);

        return createNonAwareCallSite(site, metaClass, metaMethod, params, args);
    }

    public static CallSite createCachedMethodSite(CallSite site, MetaClassImpl metaClass, CachedMethod metaMethod, Class[] params, Object[] args) {
        if (metaMethod.correctArguments(args) == args) {
            if (noWrappers(args)) {
                if (noCoerce(metaMethod,args))
                    return new PojoCachedMethodSiteNoUnwrap(site, metaClass, metaMethod, params);
                else
                    return metaMethod.createPojoMetaMethodSite(site, metaClass, params);
            }
        }
        return new PojoCachedMethodSite(site, metaClass, metaMethod, params);
    }

    public static CallSite createNonAwareCallSite(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class[] params, Object[] args) {
        if (metaMethod.correctArguments(args) == args) {
            if (noWrappers(args)) {
                if (noCoerce(metaMethod,args))
                    return new PojoMetaMethodSiteNoUnwrap(site, metaClass, metaMethod, params);
                else
                    return new PojoMetaMethodSiteNoUnwrapNoCoerce(site, metaClass, metaMethod, params);
            }
        }
        return new PojoMetaMethodSite(site, metaClass, metaMethod, params);
    }

    public static class PojoCachedMethodSite extends PojoMetaMethodSite {
        final Method reflect;

        public PojoCachedMethodSite(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class[] params) {
            super(site, metaClass, metaMethod, params);
            reflect = ((CachedMethod)metaMethod).setAccessible();
        }

        public Object invoke(Object receiver, Object[] args) throws Throwable {
            MetaClassHelper.unwrap(args);
            args = metaMethod.coerceArgumentsToClasses(args);
            return doInvoke(receiver, args, reflect);
        }
    }

    public static class PojoCachedMethodSiteNoUnwrap extends PojoCachedMethodSite {

        public PojoCachedMethodSiteNoUnwrap(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class params[]) {
            super(site, metaClass, metaMethod, params);
        }

        public final Object invoke(Object receiver, Object[] args) throws Throwable {
            args = metaMethod.coerceArgumentsToClasses(args);
            return doInvoke(receiver, args, reflect);
        }
    }

    public static class PojoCachedMethodSiteNoUnwrapNoCoerce extends PojoCachedMethodSite {

        public PojoCachedMethodSiteNoUnwrapNoCoerce(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class params[]) {
            super(site, metaClass, metaMethod, params);
        }

        public final Object invoke(Object receiver, Object[] args) throws Throwable {
            return doInvoke(receiver, args, reflect);
        }
    }

    /**
     * Call site where we know there is no need to unwrap arguments
     */
    public static class PojoMetaMethodSiteNoUnwrap extends PojoMetaMethodSite {

        public PojoMetaMethodSiteNoUnwrap(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class params[]) {
            super(site, metaClass, metaMethod, params);
        }

        public final Object invoke(Object receiver, Object[] args) throws Throwable {
            try {
                return metaMethod.doMethodInvoke(receiver,  args);
            } catch (GroovyRuntimeException gre) {
                throw ScriptBytecodeAdapter.unwrap(gre);
            }
        }
    }

    /**
     * Call site where we know there is no need neither unwrap nor coerce arguments
     */
    public static class PojoMetaMethodSiteNoUnwrapNoCoerce extends PojoMetaMethodSite {

        public PojoMetaMethodSiteNoUnwrapNoCoerce(CallSite site, MetaClassImpl metaClass, MetaMethod metaMethod, Class params[]) {
            super(site, metaClass, metaMethod, params);
        }

        public final Object invoke(Object receiver, Object[] args) throws Throwable {
            try {
                return metaMethod.invoke(receiver,  args);
            } catch (GroovyRuntimeException gre) {
                throw ScriptBytecodeAdapter.unwrap(gre);
            }
        }
    }
}
