/* *******************************************************************
 * Copyright (c) 2002 Palo Alto Research Center, Incorporated (PARC).
 * All rights reserved. 
 * This program and the accompanying materials are made available 
 * under the terms of the Eclipse Public License v1.0 
 * which accompanies this distribution and is available at 
 * http://www.eclipse.org/legal/epl-v10.html 
 *  
 * Contributors: 
 *     PARC     initial implementation 
 * ******************************************************************/

package org.aspectj.weaver.patterns;

import java.io.IOException;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Map;

import org.aspectj.bridge.IMessage;
import org.aspectj.bridge.MessageUtil;
import org.aspectj.util.FuzzyBoolean;
import org.aspectj.weaver.CompressingDataOutputStream;
import org.aspectj.weaver.ISourceContext;
import org.aspectj.weaver.IntMap;
import org.aspectj.weaver.ResolvedPointcutDefinition;
import org.aspectj.weaver.ResolvedType;
import org.aspectj.weaver.Shadow;
import org.aspectj.weaver.ShadowMunger;
import org.aspectj.weaver.TypeVariable;
import org.aspectj.weaver.TypeVariableReference;
import org.aspectj.weaver.UnresolvedType;
import org.aspectj.weaver.VersionedDataInputStream;
import org.aspectj.weaver.WeaverMessages;
import org.aspectj.weaver.World;
import org.aspectj.weaver.ast.Test;

/**
 */
// XXX needs check that arguments contains no WildTypePatterns
public class ReferencePointcut extends Pointcut {
	public UnresolvedType onType;
	public TypePattern onTypeSymbolic;
	public String name;
	public TypePatternList arguments;

	
if this is non-null then when the pointcut is concretized the result will be parameterized too.
/**
	 * if this is non-null then when the pointcut is concretized the result will be parameterized too.
	 */
	private Map<String, UnresolvedType> typeVariableMap;

	// public ResolvedPointcut binding;

	public ReferencePointcut(TypePattern onTypeSymbolic, String name, TypePatternList arguments) {
		this.onTypeSymbolic = onTypeSymbolic;
		this.name = name;
		this.arguments = arguments;
		this.pointcutKind = REFERENCE;
	}

	public ReferencePointcut(UnresolvedType onType, String name, TypePatternList arguments) {
		this.onType = onType;
		this.name = name;
		this.arguments = arguments;
		this.pointcutKind = REFERENCE;
	}

	public int couldMatchKinds() {
		return Shadow.ALL_SHADOW_KINDS_BITS;
	}

	// ??? do either of these match methods make any sense???
	public FuzzyBoolean fastMatch(FastMatchInfo type) {
		return FuzzyBoolean.MAYBE;
	}

	
Do I really match this shadow?
/**
	 * Do I really match this shadow?
	 */
	protected FuzzyBoolean matchInternal(Shadow shadow) {
		return FuzzyBoolean.NO;
	}

	public String toString() {
		StringBuffer buf = new StringBuffer();
		if (onType != null) {
			buf.append(onType);
			buf.append(".");
			// for (int i=0, len=fromType.length; i < len; i++) {
			// buf.append(fromType[i]);
			// buf.append(".");
			// }
		}
		buf.append(name);
		buf.append(arguments.toString());
		return buf.toString();
	}

	public void write(CompressingDataOutputStream s) throws IOException {
		// XXX ignores onType
		s.writeByte(Pointcut.REFERENCE);
		if (onType != null) {
			s.writeBoolean(true);
			onType.write(s);
		} else {
			s.writeBoolean(false);
		}

		s.writeUTF(name);
		arguments.write(s);
		writeLocation(s);
	}

	public static Pointcut read(VersionedDataInputStream s, ISourceContext context) throws IOException {
		UnresolvedType onType = null;
		if (s.readBoolean()) {
			onType = UnresolvedType.read(s);
		}
		ReferencePointcut ret = new ReferencePointcut(onType, s.readUTF(), TypePatternList.read(s, context));
		ret.readLocation(context, s);
		return ret;
	}

	public void resolveBindings(IScope scope, Bindings bindings) {
		if (onTypeSymbolic != null) {
			onType = onTypeSymbolic.resolveExactType(scope, bindings);
			// in this case we've already signaled an error
			if (ResolvedType.isMissing(onType)) {
				return;
			}
		}

		ResolvedType searchType;
		if (onType != null) {
			searchType = scope.getWorld().resolve(onType);
		} else {
			searchType = scope.getEnclosingType();
		}
		if (searchType.isTypeVariableReference()) {
			searchType = ((TypeVariableReference) searchType).getTypeVariable().getFirstBound().resolve(scope.getWorld());
		}

		arguments.resolveBindings(scope, bindings, true, true);
		// XXX ensure that arguments has no ..'s in it

		// check that I refer to a real pointcut declaration and that I match

		ResolvedPointcutDefinition pointcutDef = searchType.findPointcut(name);
		// if we're not a static reference, then do a lookup of outers
		if (pointcutDef == null && onType == null) {
			while (true) {
				UnresolvedType declaringType = searchType.getDeclaringType();
				if (declaringType == null) {
					break;
				}
				searchType = declaringType.resolve(scope.getWorld());
				pointcutDef = searchType.findPointcut(name);
				if (pointcutDef != null) {
					// make this a static reference
					onType = searchType;
					break;
				}
			}
		}

		if (pointcutDef == null) {
			scope.message(IMessage.ERROR, this, "can't find referenced pointcut " + name);
			return;
		}

		// check visibility
		if (!pointcutDef.isVisible(scope.getEnclosingType())) {
			scope.message(IMessage.ERROR, this, "pointcut declaration " + pointcutDef + " is not accessible");
			return;
		}

		if (Modifier.isAbstract(pointcutDef.getModifiers())) {
			if (onType != null && !onType.isTypeVariableReference()) {
				scope.message(IMessage.ERROR, this, "can't make static reference to abstract pointcut");
				return;
			} else if (!searchType.isAbstract()) {
				scope.message(IMessage.ERROR, this, "can't use abstract pointcut in concrete context");
				return;
			}
		}

		ResolvedType[] parameterTypes = scope.getWorld().resolve(pointcutDef.getParameterTypes());

		if (parameterTypes.length != arguments.size()) {
			scope.message(IMessage.ERROR, this, "incompatible number of arguments to pointcut, expected " + parameterTypes.length
					+ " found " + arguments.size());
			return;
		}

		// if (onType == null) onType = pointcutDef.getDeclaringType();
		if (onType != null) {
			if (onType.isParameterizedType()) {
				// build a type map mapping type variable names in the generic type to
				// the type parameters presented
				typeVariableMap = new HashMap<String, UnresolvedType>();
				ResolvedType underlyingGenericType = ((ResolvedType) onType).getGenericType();
				TypeVariable[] tVars = underlyingGenericType.getTypeVariables();
				ResolvedType[] typeParams = ((ResolvedType) onType).getResolvedTypeParameters();
				for (int i = 0; i < tVars.length; i++) {
					typeVariableMap.put(tVars[i].getName(), typeParams[i]);
				}
			} else if (onType.isGenericType()) {
				scope.message(MessageUtil.error(WeaverMessages.format(WeaverMessages.CANT_REFERENCE_POINTCUT_IN_RAW_TYPE),
						getSourceLocation()));
			}
		}

		for (int i = 0, len = arguments.size(); i < len; i++) {
			TypePattern p = arguments.get(i);
			// we are allowed to bind to pointcuts which use subtypes as this is type safe
			if (typeVariableMap != null) {
				p = p.parameterizeWith(typeVariableMap, scope.getWorld());
			}
			if (p == TypePattern.NO) {
				scope.message(IMessage.ERROR, this, "bad parameter to pointcut reference");
				return;
			}

			boolean reportProblem = false;
			if (parameterTypes[i].isTypeVariableReference() && p.getExactType().isTypeVariableReference()) {
				UnresolvedType One = ((TypeVariableReference) parameterTypes[i]).getTypeVariable().getFirstBound();
				UnresolvedType Two = ((TypeVariableReference) p.getExactType()).getTypeVariable().getFirstBound();
				reportProblem = !One.resolve(scope.getWorld()).isAssignableFrom(Two.resolve(scope.getWorld()));
			} else {
				reportProblem = !p.matchesSubtypes(parameterTypes[i]) && !p.getExactType().equals(UnresolvedType.OBJECT);
			}
			if (reportProblem) {
				scope.message(IMessage.ERROR, this, "incompatible type, expected " + parameterTypes[i].getName() + " found " + p
						+ ".  Check the type specified in your pointcut");
				return;
			}
		}

	}

	public void postRead(ResolvedType enclosingType) {
		arguments.postRead(enclosingType);
	}

	protected Test findResidueInternal(Shadow shadow, ExposedState state) {
		throw new RuntimeException("shouldn't happen");
	}

	// ??? This is not thread safe, but this class is not designed for multi-threading
	private boolean concretizing = false;

	// declaring type is the type that declared the member referencing this pointcut.
	// If it declares a matching private pointcut, then that pointcut should be used
	// and not one in a subtype that happens to have the same name.
	public Pointcut concretize1(ResolvedType searchStart, ResolvedType declaringType, IntMap bindings) {
		if (concretizing) {
			// Thread.currentThread().dumpStack();
			searchStart
					.getWorld()
					.getMessageHandler()
					.handleMessage(
							MessageUtil.error(WeaverMessages.format(WeaverMessages.CIRCULAR_POINTCUT, this), getSourceLocation()));
			Pointcut p = Pointcut.makeMatchesNothing(Pointcut.CONCRETE);
			p.sourceContext = sourceContext;
			return p;
		}

		try {
			concretizing = true;

			ResolvedPointcutDefinition pointcutDec;
			if (onType != null) {
				searchStart = onType.resolve(searchStart.getWorld());
				if (searchStart.isMissing()) {
					return Pointcut.makeMatchesNothing(Pointcut.CONCRETE);
				}

				if (onType.isTypeVariableReference()) {
					// need to replace on type with the binding for the type variable
					// in the declaring type
					if (declaringType.isParameterizedType()) {
						TypeVariable[] tvs = declaringType.getGenericType().getTypeVariables();
						String typeVariableName = ((TypeVariableReference) onType).getTypeVariable().getName();
						for (int i = 0; i < tvs.length; i++) {
							if (tvs[i].getName().equals(typeVariableName)) {
								ResolvedType realOnType = declaringType.getTypeParameters()[i].resolve(declaringType.getWorld());
								onType = realOnType;
								searchStart = realOnType;
								break;
							}
						}
					}
				}

			}

			if (declaringType == null) {
				declaringType = searchStart;
			}
			pointcutDec = declaringType.findPointcut(name);
			boolean foundMatchingPointcut = (pointcutDec != null && Modifier.isPrivate(pointcutDec.getModifiers()));
			if (!foundMatchingPointcut) {
				pointcutDec = searchStart.findPointcut(name);
				if (pointcutDec == null) {
					searchStart
							.getWorld()
							.getMessageHandler()
							.handleMessage(
									MessageUtil.error(
											WeaverMessages.format(WeaverMessages.CANT_FIND_POINTCUT, name, searchStart.getName()),
											getSourceLocation()));
					return Pointcut.makeMatchesNothing(Pointcut.CONCRETE);
				}
			}

			if (pointcutDec.isAbstract()) {
				// Thread.currentThread().dumpStack();
				ShadowMunger enclosingAdvice = bindings.getEnclosingAdvice();
				searchStart.getWorld().showMessage(IMessage.ERROR,
						WeaverMessages.format(WeaverMessages.ABSTRACT_POINTCUT, pointcutDec), getSourceLocation(),
						(null == enclosingAdvice) ? null : enclosingAdvice.getSourceLocation());
				return Pointcut.makeMatchesNothing(Pointcut.CONCRETE);
			}

			// System.err.println("start: " + searchStart);
			// ResolvedType[] parameterTypes = searchStart.getWorld().resolve(pointcutDec.getParameterTypes());

			TypePatternList arguments = this.arguments.resolveReferences(bindings);

			IntMap newBindings = new IntMap();
			for (int i = 0, len = arguments.size(); i < len; i++) {
				TypePattern p = arguments.get(i);
				if (p == TypePattern.NO) {
					continue;
				}
				// we are allowed to bind to pointcuts which use subtypes as this is type safe
				// this will be checked in ReferencePointcut.resolveBindings(). Can't check it here
				// as we don't know about any new parents added via decp.
				if (p instanceof BindingTypePattern) {
					newBindings.put(i, ((BindingTypePattern) p).getFormalIndex());
				}
			}

			if (searchStart.isParameterizedType()) {
				// build a type map mapping type variable names in the generic type to
				// the type parameters presented
				typeVariableMap = new HashMap<String, UnresolvedType>();
				ResolvedType underlyingGenericType = searchStart.getGenericType();
				TypeVariable[] tVars = underlyingGenericType.getTypeVariables();
				ResolvedType[] typeParams = searchStart.getResolvedTypeParameters();
				for (int i = 0; i < tVars.length; i++) {
					typeVariableMap.put(tVars[i].getName(), typeParams[i]);
				}
			}

			newBindings.copyContext(bindings);
			newBindings.pushEnclosingDefinition(pointcutDec);
			try {
				Pointcut ret = pointcutDec.getPointcut();
				if (typeVariableMap != null && !hasBeenParameterized) {
					ret = ret.parameterizeWith(typeVariableMap, searchStart.getWorld());
					ret.hasBeenParameterized = true;
				}
				return ret.concretize(searchStart, declaringType, newBindings);
			} finally {
				newBindings.popEnclosingDefinitition();
			}

		} finally {
			concretizing = false;
		}
	}

	
make a version of this pointcut with any refs to typeVariables replaced by their entry in the map. Tricky thing is, we can't
do this at the point in time this method will be called, so we make a version that will parameterize the pointcut it
ultimately resolves to.
/**
	 * make a version of this pointcut with any refs to typeVariables replaced by their entry in the map. Tricky thing is, we can't
	 * do this at the point in time this method will be called, so we make a version that will parameterize the pointcut it
	 * ultimately resolves to.
	 */
	public Pointcut parameterizeWith(Map<String, UnresolvedType> typeVariableMap, World w) {
		ReferencePointcut ret = new ReferencePointcut(onType, name, arguments);
		ret.onTypeSymbolic = onTypeSymbolic;
		ret.typeVariableMap = typeVariableMap;
		return ret;
	}

	// We want to keep the original source location, not the reference location
	protected boolean shouldCopyLocationForConcretize() {
		return false;
	}

	public boolean equals(Object other) {
		if (!(other instanceof ReferencePointcut)) {
			return false;
		}
		if (this == other) {
			return true;
		}
		ReferencePointcut o = (ReferencePointcut) other;
		return o.name.equals(name) && o.arguments.equals(arguments)
				&& ((o.onType == null) ? (onType == null) : o.onType.equals(onType));
	}

	public int hashCode() {
		int result = 17;
		result = 37 * result + ((onType == null) ? 0 : onType.hashCode());
		result = 37 * result + arguments.hashCode();
		result = 37 * result + name.hashCode();
		return result;
	}

	public Object accept(PatternNodeVisitor visitor, Object data) {
		return visitor.visit(this, data);
	}
}