001/*
002 * #%L
003 * HAPI FHIR - Core Library
004 * %%
005 * Copyright (C) 2014 - 2024 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.rest.api;
021
022import ca.uhn.fhir.context.FhirContext;
023import ca.uhn.fhir.model.api.IQueryParameterOr;
024import ca.uhn.fhir.model.api.IQueryParameterType;
025
026import java.util.ArrayList;
027import java.util.StringTokenizer;
028
029import static org.apache.commons.lang3.StringUtils.isBlank;
030
031public class QualifiedParamList extends ArrayList<String> {
032
033        private static final long serialVersionUID = 1L;
034
035        private String myQualifier;
036
037        public QualifiedParamList() {
038                super();
039        }
040
041        public QualifiedParamList(int theCapacity) {
042                super(theCapacity);
043        }
044
045        public QualifiedParamList(IQueryParameterOr<?> theNextOr, FhirContext theContext) {
046                for (IQueryParameterType next : theNextOr.getValuesAsQueryTokens()) {
047                        if (myQualifier == null) {
048                                myQualifier = next.getQueryParameterQualifier();
049                        }
050                        add(next.getValueAsQueryToken(theContext));
051                }
052        }
053
054        public String getQualifier() {
055                return myQualifier;
056        }
057
058        public void setQualifier(String theQualifier) {
059                myQualifier = theQualifier;
060        }
061
062        public static QualifiedParamList singleton(String theParamValue) {
063                return singleton(null, theParamValue);
064        }
065
066        public static QualifiedParamList singleton(String theQualifier, String theParamValue) {
067                QualifiedParamList retVal = new QualifiedParamList(1);
068                retVal.setQualifier(theQualifier);
069                retVal.add(theParamValue);
070                return retVal;
071        }
072
073        public static QualifiedParamList splitQueryStringByCommasIgnoreEscape(String theQualifier, String theParams) {
074                QualifiedParamList retVal = new QualifiedParamList();
075                retVal.setQualifier(theQualifier);
076
077                StringTokenizer tok = new StringTokenizer(theParams, ",", true);
078                String prev = null;
079                while (tok.hasMoreElements()) {
080                        String str = tok.nextToken();
081                        if (isBlank(str)) {
082                                prev = null;
083                                continue;
084                        }
085
086                        if (str.equals(",")) {
087                                if (countTrailingSlashes(prev) % 2 == 1) {
088                                        int idx = retVal.size() - 1;
089                                        String existing = retVal.get(idx);
090                                        prev = existing.substring(0, existing.length() - 1) + ',';
091                                        retVal.set(idx, prev);
092                                } else {
093                                        prev = null;
094                                }
095                                continue;
096                        }
097
098                        if (prev != null && prev.length() > 0 && prev.charAt(prev.length() - 1) == ',') {
099                                int idx = retVal.size() - 1;
100                                String existing = retVal.get(idx);
101                                prev = existing + str;
102                                retVal.set(idx, prev);
103                        } else {
104                                retVal.add(str);
105                                prev = str;
106                        }
107                }
108
109                // If no value was found, at least add that empty string as a value. It should get ignored later, but at
110                // least this lets us give a sensible error message if the parameter name was bad. See
111                // ResourceProviderR4Test#testParameterWithNoValueThrowsError_InvalidChainOnCustomSearch for an example
112                if (retVal.size() == 0) {
113                        retVal.add("");
114                }
115
116                return retVal;
117        }
118
119        private static int countTrailingSlashes(String theString) {
120                if (theString == null) {
121                        return 0;
122                }
123                int retVal = 0;
124                for (int i = theString.length() - 1; i >= 0; i--) {
125                        char nextChar = theString.charAt(i);
126                        if (nextChar != '\\') {
127                                break;
128                        }
129                        retVal++;
130                }
131                return retVal;
132        }
133}