io.questdb.griffin.engine.functions.regex.MatchStrFunctionFactory Maven / Gradle / Ivy

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 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2023 QuestDB
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 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
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 *  http://www.apache.org/licenses/LICENSE-2.0
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 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
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package io.questdb.griffin.engine.functions.regex;

import io.questdb.cairo.CairoConfiguration;
import io.questdb.cairo.sql.Function;
import io.questdb.cairo.sql.Record;
import io.questdb.cairo.sql.SymbolTableSource;
import io.questdb.griffin.FunctionFactory;
import io.questdb.griffin.PlanSink;
import io.questdb.griffin.SqlException;
import io.questdb.griffin.SqlExecutionContext;
import io.questdb.griffin.engine.functions.BooleanFunction;
import io.questdb.griffin.engine.functions.UnaryFunction;
import io.questdb.std.IntList;
import io.questdb.std.ObjList;

import java.util.regex.Matcher;

public class MatchStrFunctionFactory implements FunctionFactory {
    @Override
    public String getSignature() {
        return "~(SS)";
    }

    @Override
    public Function newInstance(
            int position,
            ObjList args,
            IntList argPositions,
            CairoConfiguration configuration,
            SqlExecutionContext sqlExecutionContext
    ) throws SqlException {
        final Function value = args.getQuick(0);
        final Function pattern = args.getQuick(1);
        final int patternPosition = argPositions.getQuick(1);
        if (pattern.isConstant()) {
            return new MatchConstPatternFunction(value, RegexUtils.createMatcher(pattern, patternPosition));
        } else if (pattern.isRuntimeConstant()) {
            return new MatchRuntimeConstPatternFunction(value, pattern, patternPosition);
        }
        throw SqlException.$(patternPosition, "not implemented: dynamic pattern would be very slow to execute");
    }

    private static class MatchConstPatternFunction extends BooleanFunction implements UnaryFunction {
        private final Matcher matcher;
        private final Function value;

        public MatchConstPatternFunction(Function value, Matcher matcher) {
            this.value = value;
            this.matcher = matcher;
        }

        @Override
        public Function getArg() {
            return value;
        }

        @Override
        public boolean getBool(Record rec) {
            CharSequence cs = getArg().getStr(rec);
            return cs != null && matcher.reset(cs).find();
        }

        @Override
        public boolean isReadThreadSafe() {
            return false;
        }

        @Override
        public void toPlan(PlanSink sink) {
            sink.val(value).val(" ~ ").val(matcher.pattern().toString());
        }
    }

    private static class MatchRuntimeConstPatternFunction extends BooleanFunction implements UnaryFunction {
        private final Function pattern;
        private final int patternPosition;
        private final Function value;
        private Matcher matcher;

        public MatchRuntimeConstPatternFunction(Function value, Function pattern, int patternPosition) {
            this.value = value;
            this.pattern = pattern;
            this.patternPosition = patternPosition;
        }

        @Override
        public Function getArg() {
            return value;
        }

        @Override
        public boolean getBool(Record rec) {
            CharSequence cs = getArg().getStr(rec);
            return cs != null && matcher.reset(cs).find();
        }

        @Override
        public void init(SymbolTableSource symbolTableSource, SqlExecutionContext executionContext) throws SqlException {
            UnaryFunction.super.init(symbolTableSource, executionContext);
            pattern.init(symbolTableSource, executionContext);
            this.matcher = RegexUtils.createMatcher(pattern, patternPosition);
        }

        @Override
        public boolean isConstant() {
            return false;
        }

        @Override
        public boolean isReadThreadSafe() {
            return false;
        }

        @Override
        public boolean isRuntimeConstant() {
            return false;
        }

        @Override
        public void toPlan(PlanSink sink) {
            sink.val(value).val(" ~ ").val(pattern.toString());
        }
    }
}