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/*
 * Copyright (c) 2010-2017, KolibriFX AS. Licensed under the Apache License, version 2.0.
 */

package com.kolibrifx.plovercrest.server;

import java.io.IOException;
import java.nio.ByteBuffer;
import org.apache.log4j.Logger;
import com.kolibrifx.plovercrest.client.PlovercrestException;
import com.kolibrifx.plovercrest.server.internal.EventType;
import com.kolibrifx.plovercrest.server.internal.engine.DeferredTableMapper;

public class TableWriter {
    private static final Logger log = Logger.getLogger(TableWriter.class);
    private final DeferredTableMapper mapper;
    private final Table table;

    TableWriter(final Table table, final DeferredTableMapper mapper) {
        this.table = table;
        this.mapper = mapper;
    }

    public void write(final long timestamp, final ByteBuffer buffer) {
        try {
            mapper.write(timestamp, buffer);
            table.dispatchEvent(EventType.ENTRY_WRITTEN);
        } catch (final IOException e) {
            throw new PlovercrestException("Failed to write", e);
        } catch (final IllegalArgumentException iae) {
            log.error("Caught illegal argument exception when writing to " + table.getName(), iae);
            log.error("Tried to write " + buffer.toString());
            throw iae;
        }
    }

    public void updateLastValidTimestamp(final long timestamp) {
        if (mapper.updateLastValidTimestamp(timestamp)) {
            table.dispatchEvent(EventType.LAST_VALID_TIMESTAMP_UPDATED);
        }
    }

    public boolean isFrozen() {
        return mapper.isFrozen();
    }

    /**
     * Freeze (write protect) the table. If it is already frozen, do nothing.
     * 
     * Note: freezing a table will also flush it.
     */
    public void freeze() {
        if (mapper.markAsFrozen()) {
            mapper.force();
            table.dispatchEvent(EventType.TABLE_FROZEN);
        }
    }

    /**
     * If the table is frozen, unfreeze it (remove the write protection). If is is not frozen, do
     * nothing. Use with care, the table was probably frozen for a reason.
     */
    public void unfreeze() {
        mapper.unfreeze();
        // Could add a TABLE_UNFROZEN event here, but wait until we need if
    }

    /**
     * Force changes to be written to disk (through {@link java.nio.MappedByteBuffer#force()}.
     */
    public void force() {
        mapper.force();
    }
}