/*
 * Copyright (c) 2016, 2019, Oracle and/or its affiliates. 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
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package jdk.jfr.consumer;

import static jdk.jfr.internal.EventInstrumentation.FIELD_DURATION;

import java.io.IOException;
import java.util.List;

import jdk.jfr.EventType;
import jdk.jfr.ValueDescriptor;
import jdk.jfr.internal.consumer.Parser;
import jdk.jfr.internal.consumer.RecordingInput;

/**
 * Parses an event and returns a {@link RecordedEvent}.
 *
 */
final class EventParser extends Parser {
    private final Parser[] parsers;
    private final EventType eventType;
    private final TimeConverter timeConverter;
    private final boolean hasDuration;
    private final List<ValueDescriptor> valueDescriptors;
    private final int startIndex;
    private long thresholdTicks = -1;
    private boolean enabled = true;

    EventParser(TimeConverter timeConverter, EventType type, Parser[] parsers) {
        this.timeConverter = timeConverter;
        this.parsers = parsers;
        this.eventType = type;
        this.hasDuration = type.getField(FIELD_DURATION) != null;
        this.startIndex = hasDuration ? 2 : 1;
        this.valueDescriptors = type.getFields();
    }

    public EventType getEventType() {
        return eventType;
    }

    public void setThreshold(long thresholdTicks) {
        this.thresholdTicks = thresholdTicks;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public boolean isEnabled() {
        return this.enabled;
    }

    public RecordedEvent parse(RecordingInput input) throws IOException {
        if (enabled) {
            long startTicks = input.readLong();
            long durationTicks = 0;
            if (hasDuration) {
                durationTicks = input.readLong();
                if (durationTicks < thresholdTicks) {
                    return null;
                }
            }
            Object[] values = new Object[parsers.length];
            for (int i = startIndex; i < parsers.length; i++) {
                values[i] = parsers[i].parse(input);
            }
            values[0] = startTicks;
            if (hasDuration) {
                values[1] = Long.valueOf(durationTicks);
            }
            long startTime = timeConverter.convertTimestamp(startTicks);
            if (hasDuration) {
                long endTime = timeConverter.convertTimestamp(startTicks + durationTicks);
                return new RecordedEvent(eventType, valueDescriptors, values, startTime, endTime, timeConverter);
            } else {
                return new RecordedEvent(eventType, valueDescriptors, values, startTime, startTime, timeConverter);
            }
        }
        return null;

    }

    @Override
    public void skip(RecordingInput input) throws IOException {
        throw new InternalError("Should not call this method. More efficent to read event size and skip ahead");
    }

}