Copyright (c) 2000, 2010 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2010 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.core.search.matching;

import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.core.search.IJavaSearchConstants;
import org.eclipse.jdt.core.search.SearchPattern;
import org.eclipse.jdt.internal.core.util.Util;

public class TypeReferencePattern extends IntersectingPattern {

	protected char[] qualification;
	protected char[] simpleName;

	protected char[] currentCategory;

	/* Optimization: case where simpleName == null */
	public int segmentsSize;
	protected char[][] segments;
	protected int currentSegment;

	private final static char[][]
		CATEGORIES = { REF, ANNOTATION_REF },
		CATEGORIES_ANNOT_REF = { ANNOTATION_REF };
	private char[][] categories;
	char typeSuffix = TYPE_SUFFIX;

	public TypeReferencePattern(char[] qualification, char[] simpleName, int matchRule) {
		this(matchRule);

		this.qualification = this.isCaseSensitive ? qualification : CharOperation.toLowerCase(qualification);
		this.simpleName = (this.isCaseSensitive || this.isCamelCase) ? simpleName : CharOperation.toLowerCase(simpleName);

		if (simpleName == null)
			this.segments = this.qualification == null ? ONE_STAR_CHAR : CharOperation.splitOn('.', this.qualification);
		else
			this.segments = null;

		if (this.segments == null)
			if (this.qualification == null)
				this.segmentsSize =  0;
			else
				this.segmentsSize =  CharOperation.occurencesOf('.', this.qualification) + 1;
		else
			this.segmentsSize = this.segments.length;

		this.mustResolve = true; // always resolve (in case of a simple name reference being a potential match)
	}
	/*
	 * Instantiate a type reference pattern with additional information for generics search
	 */
	public TypeReferencePattern(char[] qualification, char[] simpleName, String typeSignature, int matchRule) {
		this(qualification, simpleName, typeSignature, 0, TYPE_SUFFIX, matchRule);
	}
	/*
	 * Instantiate a type reference pattern with additional information for generics search and search elements nature
	 */
	public TypeReferencePattern(char[] qualification, char[] simpleName, String typeSignature, char typeSuffix, int matchRule) {
		this(qualification, simpleName, typeSignature, 0, typeSuffix, matchRule);
	}

	/*
	 * Instanciate a type reference pattern with additional information for generics search, search elements nature and fine grain information
	 */
	public TypeReferencePattern(char[] qualification, char[] simpleName, String typeSignature, int limitTo, char typeSuffix, int matchRule) {
		this(qualification, simpleName,matchRule);
		this.typeSuffix = typeSuffix;
		if (typeSignature != null) {
			// store type signatures and arguments
			this.typeSignatures = Util.splitTypeLevelsSignature(typeSignature);
			setTypeArguments(Util.getAllTypeArguments(this.typeSignatures));
			if (hasTypeArguments()) {
				this.segmentsSize = getTypeArguments().length + CharOperation.occurencesOf('/', this.typeSignatures[0]) - 1;
			}
		}
	    this.fineGrain = limitTo & 0xFFFFFFF0;
	    if (this.fineGrain == IJavaSearchConstants.ANNOTATION_TYPE_REFERENCE) {
	    	this.categories = CATEGORIES_ANNOT_REF;
	    }
	}

	/*
	 * Instantiate a type reference pattern with additional information for generics search
	 */
	public TypeReferencePattern(char[] qualification, char[] simpleName, IType type, int matchRule) {
		this(qualification, simpleName, type, 0, matchRule);
	}

	/*
	 * Instanciate a type reference pattern with additional information for generics search
	 */
	public TypeReferencePattern(char[] qualification, char[] simpleName, IType type, int limitTo, int matchRule) {
		this(qualification, simpleName,matchRule);
		storeTypeSignaturesAndArguments(type);
	    this.fineGrain = limitTo & 0xFFFFFFF0;
	}

	TypeReferencePattern(int matchRule) {
		super(TYPE_REF_PATTERN, matchRule);
		this.categories = CATEGORIES;
	}
	@Override
	public void decodeIndexKey(char[] key) {
		this.simpleName = key;
	}
	@Override
	public SearchPattern getBlankPattern() {
		return new TypeReferencePattern(R_EXACT_MATCH | R_CASE_SENSITIVE);
	}
	@Override
	public char[] getIndexKey() {
		if (this.simpleName != null)
			return this.simpleName;

		// Optimization, e.g. type reference is 'org.eclipse.jdt.core.*'
		if (this.currentSegment >= 0)
			return this.segments[this.currentSegment];
		return null;
	}
	@Override
	public char[][] getIndexCategories() {
		return this.categories;
	}
	@Override
	protected boolean hasNextQuery() {
		if (this.segments == null) return false;

		// Optimization, e.g. type reference is 'org.eclipse.jdt.core.*'
		// if package has at least 4 segments, don't look at the first 2 since they are mostly
		// redundant (e.g. in 'org.eclipse.jdt.core.*' 'org.eclipse' is used all the time)
		return --this.currentSegment >= (this.segments.length >= 4 ? 2 : 0);
	}

	@Override
	public boolean matchesDecodedKey(SearchPattern decodedPattern) {
		return true; // index key is not encoded so query results all match
	}

	@Override
	protected void resetQuery() {
		/* walk the segments from end to start as it will find less potential references using 'lang' than 'java' */
		if (this.segments != null)
			this.currentSegment = this.segments.length - 1;
	}
	@Override
	protected StringBuffer print(StringBuffer output) {
		String patternClassName = getClass().getName();
		output.append(patternClassName.substring(patternClassName.lastIndexOf('.')+1));
		output.append(": qualification<"); //$NON-NLS-1$
		if (this.qualification != null)
			output.append(this.qualification);
		else
			output.append("*"); //$NON-NLS-1$
		output.append(">, type<"); //$NON-NLS-1$
		if (this.simpleName != null)
			output.append(this.simpleName);
		else
			output.append("*"); //$NON-NLS-1$
		output.append(">"); //$NON-NLS-1$
		return super.print(output);
	}
}