001/*-
002 * #%L
003 * HAPI FHIR Storage api
004 * %%
005 * Copyright (C) 2014 - 2025 Smile CDR, Inc.
006 * %%
007 * Licensed under the Apache License, Version 2.0 (the "License");
008 * you may not use this file except in compliance with the License.
009 * You may obtain a copy of the License at
010 *
011 *      http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 * #L%
019 */
020package ca.uhn.fhir.jpa.util;
021
022import ca.uhn.fhir.jpa.patch.ParsedFhirPath;
023
024public class FhirPathUtils {
025        /**
026         * Turns an invalid FhirPath into a valid one
027         * -
028         * Do not use this for user input; but it can be used for internally parsed paths
029         */
030        public static String cleansePath(String thePath) {
031                String path = thePath;
032
033                // remove trailing .
034                while (path.endsWith(".")) {
035                        path = path.substring(0, path.length() - 1);
036                }
037
038                // remove preceding .
039                while (path.startsWith(".")) {
040                        path = path.substring(1);
041                }
042
043                // balance brackets
044                int openBrace = path.indexOf("(");
045                String remainder = path;
046                int endingIndex = openBrace == -1 ? path.length() : 0;
047                while (openBrace != -1) {
048                        int closing = RandomTextUtils.findMatchingClosingBrace(openBrace, remainder);
049                        endingIndex += closing + 1; // +1 because substring ending is exclusive
050                        remainder = remainder.substring(closing + 1);
051                        openBrace = remainder.indexOf("(");
052                }
053                path = path.substring(0, endingIndex);
054
055                return path;
056        }
057
058        /**
059         * Determines if the node is a subsetting node
060         * as described by http://hl7.org/fhirpath/N1/#subsetting
061         */
062        public static boolean isSubsettingNode(ParsedFhirPath.FhirPathNode theNode) {
063                if (theNode.getListIndex() >= 0) {
064                        return true;
065                }
066                if (theNode.isFunction()) {
067                        String funName = theNode.getValue();
068                        switch (funName) {
069                                case "first", "last", "single", "tail", "skip", "take", "exclude", "intersect" -> {
070                                        return true;
071                                }
072                        }
073                }
074                return false;
075        }
076}