/*
 * Copyright 2002-2008 the original author or authors.
 *
 * 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.springframework.aop.aspectj;

import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.aopalliance.intercept.MethodInvocation;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.aspectj.weaver.BCException;
import org.aspectj.weaver.patterns.NamePattern;
import org.aspectj.weaver.reflect.ReflectionWorld;
import org.aspectj.weaver.tools.ContextBasedMatcher;
import org.aspectj.weaver.tools.FuzzyBoolean;
import org.aspectj.weaver.tools.JoinPointMatch;
import org.aspectj.weaver.tools.MatchingContext;
import org.aspectj.weaver.tools.PointcutDesignatorHandler;
import org.aspectj.weaver.tools.PointcutExpression;
import org.aspectj.weaver.tools.PointcutParameter;
import org.aspectj.weaver.tools.PointcutParser;
import org.aspectj.weaver.tools.PointcutPrimitive;
import org.aspectj.weaver.tools.ShadowMatch;

import org.springframework.aop.ClassFilter;
import org.springframework.aop.IntroductionAwareMethodMatcher;
import org.springframework.aop.MethodMatcher;
import org.springframework.aop.ProxyMethodInvocation;
import org.springframework.aop.framework.autoproxy.ProxyCreationContext;
import org.springframework.aop.interceptor.ExposeInvocationInterceptor;
import org.springframework.aop.support.AbstractExpressionPointcut;
import org.springframework.aop.support.AopUtils;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;

/**
 * Spring {@link org.springframework.aop.Pointcut} implementation
 * that uses the AspectJ weaver to evaluate a pointcut expression.
 *
 * <p>The pointcut expression value is an AspectJ expression. This can
 * reference other pointcuts and use composition and other operations.
 *
 * <p>Naturally, as this is to be processed by Spring AOP's proxy-based model,
 * only method execution pointcuts are supported.
 *
 * @author Rob Harrop
 * @author Adrian Colyer
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Ramnivas Laddad
 * @since 2.0
 */
public class AspectJExpressionPointcut extends AbstractExpressionPointcut
		implements ClassFilter, IntroductionAwareMethodMatcher, BeanFactoryAware {

	private static final Set DEFAULT_SUPPORTED_PRIMITIVES = new HashSet();

	static {
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.EXECUTION);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.ARGS);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.REFERENCE);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.THIS);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.TARGET);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.WITHIN);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.AT_ANNOTATION);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.AT_WITHIN);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.AT_ARGS);
		DEFAULT_SUPPORTED_PRIMITIVES.add(PointcutPrimitive.AT_TARGET);
	}


	private static final Log logger = LogFactory.getLog(AspectJExpressionPointcut.class);

	private final Map shadowMapCache = new HashMap();

	private PointcutParser pointcutParser;

	private Class pointcutDeclarationScope;

	private String[] pointcutParameterNames = new String[0];

	private Class[] pointcutParameterTypes = new Class[0];

	private BeanFactory beanFactory;

	private PointcutExpression pointcutExpression;


	/**
	 * Create a new default AspectJExpressionPointcut.
	 */
	public AspectJExpressionPointcut() {
		this(DEFAULT_SUPPORTED_PRIMITIVES);
	}

	/**
	 * Create a new AspectJExpressionPointcut with the given supported primitives.
	 * @param supportedPrimitives Set of {@link org.aspectj.weaver.tools.PointcutPrimitive}
	 * instances
	 */
	public AspectJExpressionPointcut(Set supportedPrimitives) {
		this.pointcutParser =
				PointcutParser.getPointcutParserSupportingSpecifiedPrimitivesAndUsingContextClassloaderForResolution(
						supportedPrimitives);
		this.pointcutParser.registerPointcutDesignatorHandler(new BeanNamePointcutDesignatorHandler());
	}

	/**
	 * Create a new AspectJExpressionPointcut with the given settings.
	 * @param declarationScope the declaration scope for the pointcut
	 * @param paramNames the parameter names for the pointcut
	 * @param paramTypes the parameter types for the pointcut
	 */
	public AspectJExpressionPointcut(Class declarationScope, String[] paramNames, Class[] paramTypes) {
		this(DEFAULT_SUPPORTED_PRIMITIVES);
		this.pointcutDeclarationScope = declarationScope;
		if (paramNames.length != paramTypes.length) {
			throw new IllegalStateException(
					"Number of pointcut parameter names must match number of pointcut parameter types");
		}
		this.pointcutParameterNames = paramNames;
		this.pointcutParameterTypes = paramTypes;
	}


	/**
	 * Set the declaration scope for the pointcut.
	 */
	public void setPointcutDeclarationScope(Class pointcutDeclarationScope) {
		this.pointcutDeclarationScope = pointcutDeclarationScope;
	}

	/**
	 * Set the parameter names for the pointcut.
	 */
	public void setParameterNames(String[] names) {
		this.pointcutParameterNames = names;
	}

	/**
	 * Set the parameter types for the pointcut.
	 */
	public void setParameterTypes(Class[] types) {
		this.pointcutParameterTypes = types;
	}

	public void setBeanFactory(BeanFactory beanFactory) {
		this.beanFactory = beanFactory;
	}


	public ClassFilter getClassFilter() {
		checkReadyToMatch();
		return this;
	}

	public MethodMatcher getMethodMatcher() {
		checkReadyToMatch();
		return this;
	}


	/**
	 * Check whether this pointcut is ready to match,
	 * lazily building the underlying AspectJ pointcut expression.
	 */
	private void checkReadyToMatch() {
		if (getExpression() == null) {
			throw new IllegalStateException("Must set property 'expression' before attempting to match");
		}
		if (this.pointcutExpression == null) {
			this.pointcutExpression = buildPointcutExpression();
		}
	}

	/**
	 * Build the underlying AspectJ pointcut expression.
	 */
	private PointcutExpression buildPointcutExpression() {
		PointcutParameter[] pointcutParameters = new PointcutParameter[this.pointcutParameterNames.length];
		for (int i = 0; i < pointcutParameters.length; i++) {
			pointcutParameters[i] = this.pointcutParser.createPointcutParameter(
					this.pointcutParameterNames[i], this.pointcutParameterTypes[i]);
		}
		return this.pointcutParser.parsePointcutExpression(
				replaceBooleanOperators(getExpression()), this.pointcutDeclarationScope, pointcutParameters);
	}

	/**
	 * If a pointcut expression has been specified in XML, the user cannot
	 * write <code>and</code> as "&&" (though &amp;&amp; will work).
	 * We also allow <code>and</code> between two pointcut sub-expressions.
	 * <p>This method converts back to <code>&&</code> for the AspectJ pointcut parser.
	 */
	private String replaceBooleanOperators(String pcExpr) {
		pcExpr = StringUtils.replace(pcExpr," and "," && ");
		pcExpr = StringUtils.replace(pcExpr, " or ", " || ");
		pcExpr = StringUtils.replace(pcExpr, " not ", " ! ");
		return pcExpr;
	}

	/**
	 * Return the underlying AspectJ pointcut expression.
	 */
	public PointcutExpression getPointcutExpression() {
		checkReadyToMatch();
		return this.pointcutExpression;
	}


	public boolean matches(Class targetClass) {
		checkReadyToMatch();
		try {
			return this.pointcutExpression.couldMatchJoinPointsInType(targetClass);
		}
		catch (BCException ex) {
			logger.debug("PointcutExpression matching rejected target class", ex);
			return false;
		}
	}

	public boolean matches(Method method, Class targetClass, boolean beanHasIntroductions) {
		checkReadyToMatch();
		Method targetMethod = AopUtils.getMostSpecificMethod(method, targetClass);
		ShadowMatch shadowMatch = null;
		try {
			shadowMatch = getShadowMatch(targetMethod, method);
		}
		catch (ReflectionWorld.ReflectionWorldException ex) {
			// Could neither introspect the target class nor the proxy class ->
			// let's simply consider this method as non-matching.
			return false;
		}

		// Special handling for this, target, @this, @target, @annotation
		// in Spring - we can optimize since we know we have exactly this class,