/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.parquet.column.page.mem;

import static org.apache.parquet.bytes.BytesInput.copy;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.parquet.bytes.BytesInput;
import org.apache.parquet.column.Encoding;
import org.apache.parquet.column.page.DataPage;
import org.apache.parquet.column.page.DataPageV1;
import org.apache.parquet.column.page.DataPageV2;
import org.apache.parquet.column.page.DictionaryPage;
import org.apache.parquet.column.page.PageWriter;
import org.apache.parquet.column.statistics.SizeStatistics;
import org.apache.parquet.column.statistics.Statistics;
import org.apache.parquet.column.statistics.geospatial.GeospatialStatistics;
import org.apache.parquet.io.ParquetEncodingException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MemPageWriter implements PageWriter {
  private static final Logger LOG = LoggerFactory.getLogger(MemPageWriter.class);

  private final List<DataPage> pages = new ArrayList<>();
  private DictionaryPage dictionaryPage;
  private long memSize = 0;
  private long totalValueCount = 0;

  @Override
  public void writePage(
      BytesInput bytesInput,
      int valueCount,
      Statistics statistics,
      Encoding rlEncoding,
      Encoding dlEncoding,
      Encoding valuesEncoding)
      throws IOException {
    if (valueCount == 0) {
      throw new ParquetEncodingException("illegal page of 0 values");
    }
    memSize += bytesInput.size();
    pages.add(new DataPageV1(
        BytesInput.copy(bytesInput),
        valueCount,
        (int) bytesInput.size(),
        statistics,
        rlEncoding,
        dlEncoding,
        valuesEncoding));
    totalValueCount += valueCount;
    LOG.debug("page written for {} bytes and {} records", bytesInput.size(), valueCount);
  }

  @Override
  public void writePage(
      BytesInput bytesInput,
      int valueCount,
      int rowCount,
      Statistics<?> statistics,
      Encoding rlEncoding,
      Encoding dlEncoding,
      Encoding valuesEncoding)
      throws IOException {
    writePage(bytesInput, valueCount, statistics, rlEncoding, dlEncoding, valuesEncoding);
  }

  @Override
  public void writePage(
      BytesInput bytesInput,
      int valueCount,
      int rowCount,
      Statistics<?> statistics,
      SizeStatistics sizeStatistics,
      GeospatialStatistics geospatialStatistics,
      Encoding rlEncoding,
      Encoding dlEncoding,
      Encoding valuesEncoding)
      throws IOException {
    writePage(bytesInput, valueCount, statistics, rlEncoding, dlEncoding, valuesEncoding);
  }

  @Override
  public void writePageV2(
      int rowCount,
      int nullCount,
      int valueCount,
      BytesInput repetitionLevels,
      BytesInput definitionLevels,
      Encoding dataEncoding,
      BytesInput data,
      Statistics<?> statistics)
      throws IOException {
    if (valueCount == 0) {
      throw new ParquetEncodingException("illegal page of 0 values");
    }
    long size = repetitionLevels.size() + definitionLevels.size() + data.size();
    memSize += size;
    pages.add(DataPageV2.uncompressed(
        rowCount,
        nullCount,
        valueCount,
        copy(repetitionLevels),
        copy(definitionLevels),
        dataEncoding,
        copy(data),
        statistics));
    totalValueCount += valueCount;
    LOG.debug("page written for {} bytes and {} records", size, valueCount);
  }

  @Override
  public void writePageV2(
      int rowCount,
      int nullCount,
      int valueCount,
      BytesInput repetitionLevels,
      BytesInput definitionLevels,
      Encoding dataEncoding,
      BytesInput data,
      Statistics<?> statistics,
      SizeStatistics sizeStatistics,
      GeospatialStatistics geospatialStatistics)
      throws IOException {
    writePageV2(
        rowCount, nullCount, valueCount, repetitionLevels, definitionLevels, dataEncoding, data, statistics);
  }

  @Override
  public long getMemSize() {
    return memSize;
  }

  public List<DataPage> getPages() {
    return pages;
  }

  public DictionaryPage getDictionaryPage() {
    return dictionaryPage;
  }

  public long getTotalValueCount() {
    return totalValueCount;
  }

  @Override
  public long allocatedSize() {
    // this store keeps only the bytes written
    return memSize;
  }

  @Override
  public void writeDictionaryPage(DictionaryPage dictionaryPage) throws IOException {
    if (this.dictionaryPage != null) {
      throw new ParquetEncodingException("Only one dictionary page per block");
    }
    this.memSize += dictionaryPage.getBytes().size();
    this.dictionaryPage = dictionaryPage.copy();
    LOG.debug(
        "dictionary page written for {} bytes and {} records",
        dictionaryPage.getBytes().size(),
        dictionaryPage.getDictionarySize());
  }

  @Override
  public String memUsageString(String prefix) {
    return String.format("%s %,d bytes", prefix, memSize);
  }
}
