/* *******************************************************************
 * 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.util.Map;

import org.aspectj.weaver.CompressingDataOutputStream;
import org.aspectj.weaver.ISourceContext;
import org.aspectj.weaver.ResolvedType;
import org.aspectj.weaver.UnresolvedType;
import org.aspectj.weaver.VersionedDataInputStream;
import org.aspectj.weaver.World;

public class ThrowsPattern extends PatternNode {
	private TypePatternList required;
	private TypePatternList forbidden;

	public static final ThrowsPattern ANY = new ThrowsPattern(TypePatternList.EMPTY, TypePatternList.EMPTY);

	public ThrowsPattern(TypePatternList required, TypePatternList forbidden) {
		this.required = required;
		this.forbidden = forbidden;
	}

	public TypePatternList getRequired() {
		return required;
	}

	public TypePatternList getForbidden() {
		return forbidden;
	}

	public String toString() {
		if (this == ANY) {
			return "";
		}

		String ret = "throws " + required.toString();
		if (forbidden.size() > 0) {
			ret = ret + " !(" + forbidden.toString() + ")";
		}
		return ret;
	}

	public boolean equals(Object other) {
		if (!(other instanceof ThrowsPattern)) {
			return false;
		}
		ThrowsPattern o = (ThrowsPattern) other;
		boolean ret = o.required.equals(this.required) && o.forbidden.equals(this.forbidden);
		return ret;
	}

	public int hashCode() {
		int result = 17;
		result = 37 * result + required.hashCode();
		result = 37 * result + forbidden.hashCode();
		return result;
	}

	public ThrowsPattern resolveBindings(IScope scope, Bindings bindings) {
		if (this == ANY) {
			return this;
		}
		required = required.resolveBindings(scope, bindings, false, false);
		forbidden = forbidden.resolveBindings(scope, bindings, false, false);
		return this;
	}

	public ThrowsPattern parameterizeWith(Map/* name -> resolved type */typeVariableMap, World w) {
		ThrowsPattern ret = new ThrowsPattern(required.parameterizeWith(typeVariableMap, w), forbidden.parameterizeWith(
				typeVariableMap, w));
		ret.copyLocationFrom(this);
		return ret;
	}

	public boolean matches(UnresolvedType[] tys, World world) {
		if (this == ANY) {
			return true;
		}

		// System.out.println("matching: " + this + " with " + Arrays.asList(tys));

		ResolvedType[] types = world.resolve(tys);
		// int len = types.length;
		for (int j = 0, lenj = required.size(); j < lenj; j++) {
			if (!matchesAny(required.get(j), types)) {
				return false;
			}
		}
		for (int j = 0, lenj = forbidden.size(); j < lenj; j++) {
			if (matchesAny(forbidden.get(j), types)) {
				return false;
			}
		}
		return true;
	}

	private boolean matchesAny(TypePattern typePattern, ResolvedType[] types) {
		for (int i = types.length - 1; i >= 0; i--) {
			if (typePattern.matchesStatically(types[i])) {
				return true;
			}
		}
		return false;
	}

	public static ThrowsPattern read(VersionedDataInputStream s, ISourceContext context) throws IOException {
		TypePatternList required = TypePatternList.read(s, context);
		TypePatternList forbidden = TypePatternList.read(s, context);
		if (required.size() == 0 && forbidden.size() == 0) {
			return ANY;
		}
		ThrowsPattern ret = new ThrowsPattern(required, forbidden);
		// XXXret.readLocation(context, s);
		return ret;
	}

	public void write(CompressingDataOutputStream s) throws IOException {
		required.write(s);
		forbidden.write(s);
		// XXXwriteLocation(s);
	}

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

	public Object traverse(PatternNodeVisitor visitor, Object data) {
		Object ret = accept(visitor, data);
		forbidden.traverse(visitor, data);
		required.traverse(visitor, data);
		return ret;
	}
}