// Copyright (C) 2010 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.gerrit.server.query.change;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gerrit.server.patch.PatchListCache;
import com.google.gerrit.server.query.OperatorPredicate;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Provider;
import dk.brics.automaton.Automaton;
import dk.brics.automaton.RegExp;
import dk.brics.automaton.RunAutomaton;
import java.util.Arrays;
class RegexFilePredicate extends OperatorPredicate<ChangeData> {
private final Provider<ReviewDb> db;
private final PatchListCache cache;
private final RunAutomaton pattern;
private final String prefixBegin;
private final String prefixEnd;
private final int prefixLen;
private final boolean prefixOnly;
RegexFilePredicate(Provider<ReviewDb> db, PatchListCache plc, String re) {
super(ChangeQueryBuilder.FIELD_FILE, re);
this.db = db;
this.cache = plc;
if (re.startsWith("^")) {
re = re.substring(1);
}
if (re.endsWith("$") && !re.endsWith("\\$")) {
re = re.substring(0, re.length() - 1);
}
Automaton automaton = new RegExp(re).toAutomaton();
prefixBegin = automaton.getCommonPrefix();
prefixLen = prefixBegin.length();
if (0 < prefixLen) {
char max = (char) (prefixBegin.charAt(prefixLen - 1) + 1);
prefixEnd = prefixBegin.substring(0, prefixLen - 1) + max;
prefixOnly = re.equals(prefixBegin + ".*");
} else {
prefixEnd = "";
prefixOnly = false;
}
pattern = prefixOnly ? null : new RunAutomaton(automaton);
}
@Override
public boolean match(ChangeData object) throws OrmException {
String[] files = object.currentFilePaths(db, cache);
if (files != null) {
int begin, end;
if (0 < prefixLen) {
begin = find(files, prefixBegin);
end = find(files, prefixEnd);
} else {
begin = 0;
end = files.length;
}
if (prefixOnly) {
return begin < end;
}
while (begin < end) {
if (pattern.run(files[begin++])) {
return true;
}
}
return false;
} else {
// The ChangeData can't do expensive lookups right now. Bypass
// them and include the result anyway. We might be able to do
// a narrow later on to a smaller set.
//
return true;
}
}
private static int find(String[] files, String p) {
int r = Arrays.binarySearch(files, p);
return r < 0 ? -(r + 1) : r;
}
@Override
public int getCost() {
return 1;
}
}