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 * Copyright (c) 2020, Datadog, Inc. All rights reserved.
 * Copyright (c) 2025 SAP SE. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package jdk.jfr.internal.settings;

import static jdk.jfr.internal.util.TimespanUnit.SECONDS;
import static jdk.jfr.internal.util.TimespanUnit.MILLISECONDS;

import java.util.Objects;
import java.util.Set;

import jdk.jfr.Description;
import jdk.jfr.SettingControl;
import jdk.jfr.Label;
import jdk.jfr.MetadataDefinition;
import jdk.jfr.Name;
import jdk.jfr.internal.PlatformEventType;
import jdk.jfr.internal.Type;
import jdk.jfr.internal.util.TimespanRate;
import jdk.jfr.internal.util.Utils;

@MetadataDefinition
@Label("CPUThrottleSetting")
@Description("Upper bounds the emission rate for CPU time samples")
@Name(Type.SETTINGS_PREFIX + "Rate")
public final class CPUThrottleSetting extends SettingControl {
    public static final String DEFAULT_VALUE = "0/s";
    private final PlatformEventType eventType;
    private String value = DEFAULT_VALUE;

    public CPUThrottleSetting(PlatformEventType eventType) {
       this.eventType = Objects.requireNonNull(eventType);
    }

    @Override
    public String combine(Set<String> values) {
        TimespanRate max = null;
        for (String value : values) {
            TimespanRate rate = TimespanRate.of(value);
            if (rate != null) {
                if (max == null || rate.isHigher(max)) {
                    max = rate;
                }
                max = new TimespanRate(max.rate(), max.autoAdapt() || rate.autoAdapt());
            }
        }
        // "off" is not supported
        return Objects.requireNonNullElse(max.toString(), DEFAULT_VALUE);
    }

    @Override
    public void setValue(String value) {
        TimespanRate rate = TimespanRate.of(value);
        if (rate != null) {
            eventType.setCPUThrottle(rate);
            this.value = value;
        }
    }

    @Override
    public String getValue() {
        return value;
    }
}