/*
 * Copyright (C) 2014, United States Government, as represented by the
 * Administrator of the National Aeronautics and Space Administration.
 * All rights reserved.
 *
 * The Java Pathfinder core (jpf-core) platform is 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 gov.nasa.jpf.vm;

import gov.nasa.jpf.annotation.MJI;


/**
 * a full peer for the AtomicIntegerFieldUpdater
 */
public class JPF_java_util_concurrent_atomic_AtomicIntegerFieldUpdater extends AtomicFieldUpdater {

  @MJI
  public void $init__Ljava_lang_Class_2Ljava_lang_String_2__V (MJIEnv env, int objRef, int tClsObjRef, int fNameRef) {

    // direct Object subclass, so we don't have to call a super ctor

    ClassInfo ci = env.getReferredClassInfo( tClsObjRef);
    String fname = env.getStringObject(fNameRef);

    FieldInfo fi = ci.getInstanceField(fname);
    ClassInfo fci = fi.getTypeClassInfo();

    if (!fci.isPrimitive() || !fci.getName().equals("int")) {
      // that's also just an approximation, but we need to check
      env.throwException("java.lang.RuntimeException", "wrong field type");
    }

    int fidx = fi.getFieldIndex();
    env.setIntField(objRef, "fieldId", fidx);
  }

  @MJI
  public boolean compareAndSet__Ljava_lang_Object_2II__Z (MJIEnv env, int objRef, int tRef, int fExpect, int fUpdate) {    
    if (tRef == MJIEnv.NULL){
      env.throwException("java.lang.NullPointerException", "AtomicFieldUpdater called on null object");
      return false;
    }
    
    ThreadInfo ti = env.getThreadInfo();
    ElementInfo ei = ti.getModifiableElementInfo(tRef);
    FieldInfo fi = getFieldInfo( ti.getElementInfo(objRef), ei);

    if (reschedulesAccess(ti, ei, fi)){
      env.repeatInvocation();
      return false;
    }
        
    int v = ei.getIntField(fi);
    if (v == fExpect) {
      ei = ei.getModifiableInstance();
      ei.setIntField(fi, fUpdate);
      return true;
    } else {
      return false;
    }
  }

  @MJI
  public boolean weakCompareAndSet__Ljava_lang_Object_2II__Z (MJIEnv env, int objRef, int tRef, int fExpect, int fUpdate) {
    return (compareAndSet__Ljava_lang_Object_2II__Z(env, objRef, tRef, fExpect, fUpdate));
  }

  @MJI
  public void set__Ljava_lang_Object_2I__V (MJIEnv env, int objRef, int tRef, int fNewValue) {
    if (tRef == MJIEnv.NULL){
      env.throwException("java.lang.NullPointerException", "AtomicFieldUpdater called on null object");
      return;
    }
    
    ThreadInfo ti = env.getThreadInfo();
    ElementInfo ei = ti.getModifiableElementInfo(tRef);
    FieldInfo fi = getFieldInfo( ti.getElementInfo(objRef), ei);

    if (reschedulesAccess(ti, ei, fi)){
      env.repeatInvocation();
      return;
    }

    ei.setIntField(fi, fNewValue);
  }

  @MJI
  public void lazySet__Ljava_lang_Object_2I__V (MJIEnv env, int objRef, int tRef, int fNewValue) {
    set__Ljava_lang_Object_2I__V(env, objRef, tRef, fNewValue);
  }

  @MJI
  public int get__Ljava_lang_Object_2__I(MJIEnv env, int objRef, int tRef) {
    if (tRef == MJIEnv.NULL){
      env.throwException("java.lang.NullPointerException", "AtomicFieldUpdater called on null object");
      return 0;
    }
    
    ThreadInfo ti = env.getThreadInfo();
    ElementInfo ei = ti.getElementInfo(tRef);
    FieldInfo fi = getFieldInfo( ti.getElementInfo(objRef), ei);

    if (reschedulesAccess(ti, ei, fi)){
      env.repeatInvocation();
      return 0;
    }


    return ei.getIntField(fi);
  }

  @MJI
  public int getAndSet__Ljava_lang_Object_2I__I (MJIEnv env, int objRef, int tRef, int fNewValue) {
    if (tRef == MJIEnv.NULL){
      env.throwException("java.lang.NullPointerException", "AtomicFieldUpdater called on null object");
      return 0;
    }
    
    ThreadInfo ti = env.getThreadInfo();
    ElementInfo ei = ti.getModifiableElementInfo(tRef);
    FieldInfo fi = getFieldInfo( ti.getElementInfo(objRef), ei);

    if (reschedulesAccess(ti, ei, fi)){
      env.repeatInvocation();
      return 0;
    }

    int result = ei.getIntField(fi);
    ei.setIntField(fi, fNewValue);

    return result;
  }

  @MJI
  public int getAndAdd__Ljava_lang_Object_2I__I (MJIEnv env, int objRef, int tRef, int fDelta) {
    if (tRef == MJIEnv.NULL){
      env.throwException("java.lang.NullPointerException", "AtomicFieldUpdater called on null object");
      return 0;
    }
    
    ThreadInfo ti = env.getThreadInfo();
    ElementInfo ei = ti.getModifiableElementInfo(tRef);
    FieldInfo fi = getFieldInfo( ti.getElementInfo(objRef), ei);

    if (reschedulesAccess(ti, ei, fi)){
      env.repeatInvocation();
      return 0;
    }

    int result = ei.getIntField(fi);
    ei.setIntField(fi, result + fDelta);

    return result;
  }

}