/*******************************************************************************
 * Copyright (c) 2008 IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.wst.sse.ui.internal.correction;

import java.util.Map;

import org.eclipse.jface.text.source.Annotation;
import org.eclipse.wst.sse.ui.internal.reconcile.TemporaryAnnotation;

/*
 * Copied from org.eclipse.ui.internal.ide.registry.MarkerQuery
 */
class AnnotationQuery {
	/**
	 * The annotation type targetted by this query. May be <code>null</code>.
	 */
	private String type;

	/**
	 * A sorted list of the attributes targetted by this query. The list is
	 * sorted from least to greatest according to <code>Sting.compare</code>
	 */
	private String[] attributes;

	/**
	 * Cached hash code value
	 */
	private int hashCode;

	/**
	 * Creates a new annotation query with the given type and attributes.
	 * <p>
	 * The type may be <code>null</code>. The attributes may be empty, but
	 * not <code>null</code>.
	 * </p>
	 * 
	 * @param problemType
	 *            the targetted annotation type
	 * @param markerAttributes
	 *            the targetted annotation attributes
	 */
	public AnnotationQuery(String annotationType, String[] annotationAttributes) {
		if (annotationAttributes == null) {
			throw new IllegalArgumentException();
		}

		type = annotationType;
		attributes = annotationAttributes;
		computeHashCode();
	}

	/**
	 * Performs a query against the given annotation.
	 * <p>
	 * Returns a <code>AnnotationQueryResult</code> if the marker is
	 * appropriate for this query (correct type and has all of the query
	 * attributes), otherwise <code>null</code> is returned.
	 * 
	 * @param annotation
	 *            the annotation to perform the query against
	 * @return a annotation query result or <code>null</code>
	 */
	public AnnotationQueryResult performQuery(Annotation anno) {
		if (!(anno instanceof TemporaryAnnotation))
			return null;

		Map annoAttributes = ((TemporaryAnnotation) anno).getAttributes();
		// Check type
		if (type != null) {
			String problemType = (String) annoAttributes.get("problemType");
			if (!type.equals(problemType))
				return null;
		}

		String[] values = new String[attributes.length];
		for (int i = 0; i < attributes.length; i++) {
			Object value = annoAttributes.get(attributes[i]);
			if (value == null) {
				return null;
			}
			values[i] = value.toString();
		}
		// Create and return the result
		return new AnnotationQueryResult(values);
	}

	/*
	 * (non-Javadoc) Method declared on Object.
	 */
	public boolean equals(Object o) {
		if (!(o instanceof AnnotationQuery)) {
			return false;
		}

		if (o == this) {
			return true;
		}

		AnnotationQuery mq = (AnnotationQuery) o;
		if (!(type == null ? mq.type == null : type.equals(mq.type))) {
			return false;
		}

		if (attributes.length != mq.attributes.length) {
			return false;
		}

		for (int i = 0; i < attributes.length; i++) {
			if (!(attributes[i].equals(mq.attributes[i]))) {
				return false;
			}
		}

		return true;
	}

	/*
	 * (non-Javadoc) Method declared on Object.
	 */
	public int hashCode() {
		return hashCode;
	}

	/**
	 * Computes the hash code for this instance.
	 */
	public void computeHashCode() {
		hashCode = 19;

		if (type != null) {
			hashCode = hashCode * 37 + type.hashCode();
		}

		for (int i = 0; i < attributes.length; i++) {
			hashCode = hashCode * 37 + attributes[i].hashCode();
		}
	}

	/**
	 * Returns the targetted marker type. May be <code>null</code>
	 * 
	 * @return the targetted marker type
	 */
	public String getType() {
		return type;
	}

	/**
	 * Returns the targetted attributes. The array may be empty.
	 * 
	 * @return the targetted attributes
	 */
	public String[] getAttributes() {
		return attributes;
	}
}