/*
    *  Copyright 2013 Christopher Pheby
    *
    *  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 org.jadira.reflection.access.invokedynamic;
  
  import java.lang.invoke.CallSite;
  import java.lang.invoke.MethodHandle;
  import java.lang.invoke.MethodType;
  import java.lang.reflect.Field;
  
  import org.dynalang.dynalink.DefaultBootstrapper;
  import org.jadira.reflection.access.api.FieldAccess;
  
  /**
   * FieldAccess implementation using an InvokeDynamic based strategy (using ASM and Dynalang)
   * @param <C> The Class containing the Field to be accessed
   */
  public class InvokeDynamicFieldAccess<C> implements FieldAccess<C> {
  
      private String fieldName;
  	
  	private Class<C> declaringClass;
  	private Class<?> fieldClass;
  	private Field field;	
  
  	CallSite getCallSite;
  	CallSite setCallSite;
  	
  	MethodHandle setMh;
  	MethodHandle getMh;
  	
  	@SuppressWarnings("unchecked")
  	private InvokeDynamicFieldAccess(InvokeDynamicClassAccess<C> classAccess, Field f) {
  		
  		this.declaringClass = (Class<C>) f.getDeclaringClass();
  		
  		this.fieldClass = f.getType();
  		
  		this.fieldName = f.getName();
  		
  		this.field = f;
  		
  		setCallSite = DefaultBootstrapper.publicBootstrap(null, "dyn:setProp:" + fieldName, MethodType.methodType(void.class, Object.class, fieldClass));
  		getCallSite = DefaultBootstrapper.publicBootstrap(null, "dyn:getProp:" + fieldName, MethodType.methodType(fieldClass, Object.class));
  		
  		setMh = setCallSite.dynamicInvoker();
  	    getMh = getCallSite.dynamicInvoker();
  	}
  	
  	@Override
  	public Class<C> declaringClass() {
  		return declaringClass;
  	}
  
  	@Override
  	public Class<?> fieldClass() {
  		return fieldClass;
  	}
  
  	@Override
  	public Field field() {
  		return field;
  	}
  	
  	/**
  	 * Get a new instance that can access the given Field
  	 * @param classAccess The InvokeDynamicClassAccess instance to be delegated to
  	 * @param f Field to be accessed
  	 * @param <C> The type of class being accessed
  	 * @return New InvokeDynamicFieldAccess instance
  	 */
  	public static final <C> InvokeDynamicFieldAccess<C> get(InvokeDynamicClassAccess<C> classAccess, Field f) {
  		return new InvokeDynamicFieldAccess<C>(classAccess, f);
  	}
  
  	@Override
  	public Object getValue(C parent) {
          try {
              return getMh.invokeExact(parent);
          } catch (Throwable e) {
              throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                      + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
          }
  	}
  
  	@Override
  	public void putValue(C parent, Object newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public boolean getBooleanValue(C parent) {
         try {
             return (boolean) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public byte getByteValue(C parent) {
         try {
             return (byte) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public char getCharValue(C parent) {
         try {
             return (char) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public short getShortValue(C parent) {
         try {
             return (short) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public int getIntValue(C parent) {
         try {
             return (int) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public long getLongValue(C parent) {
         try {
             return (long) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public float getFloatValue(C parent) {
         try {
             return (float) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public double getDoubleValue(C parent) {
         try {
             return (double) getMh.invokeExact(parent);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putBooleanValue(C parent, boolean newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putByteValue(C parent, byte newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putCharValue(C parent, char newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putShortValue(C parent, short newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putIntValue(C parent, int newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putLongValue(C parent, long newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putFloatValue(C parent, float newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 
 	@Override
 	public void putDoubleValue(C parent, double newFieldValue) {
 	    try {
             setMh.invokeExact(parent, newFieldValue);
         } catch (Throwable e) {
             throw new IllegalStateException("Problem accessing {" + field.getName() + "} of object {"
                     + System.identityHashCode(parent) + "}: " + e.getMessage(), e);
         }
 	}
 }