content: /*
   * Copyright 2002-2019 Drew Noakes and contributors
   *
   *    Licensed 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
   *
   *        https://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.
   *
   * More information about this project is available at:
   *
   *    https://drewnoakes.com/code/exif/
   *    https://github.com/drewnoakes/metadata-extractor
   */
  package com.drew.metadata.avi;
  
  import com.drew.imaging.riff.RiffHandler;
  import com.drew.lang.ByteArrayReader;
  import com.drew.lang.annotations.NotNull;
  import com.drew.metadata.Metadata;
  
  import java.io.IOException;
  
  /**
   * Implementation of {@link RiffHandler} specialising in AVI support.
   *
   * Extracts data from chunk/list types:
   *
   * <ul>
   *     <li><code>"avih"</code>: width, height, streams</li>
   *     <li><code>"strh"</code>: frames/second, samples/second, duration, video codec</li>
   * </ul>
   *
   * Sources: https://www.alexander-noe.com/video/documentation/avi.pdf
   *          https://msdn.microsoft.com/en-us/library/ms899422.aspx
   *          https://www.loc.gov/preservation/digital/formats/fdd/fdd000025.shtml
   *
   * @author Payton Garland
   */
  public class AviRiffHandler implements RiffHandler
  {
      @NotNull
      private final AviDirectory _directory;
  
      public AviRiffHandler(@NotNull Metadata metadata)
      {
          _directory = new AviDirectory();
          metadata.addDirectory(_directory);
      }
  
      public boolean shouldAcceptRiffIdentifier(@NotNull String identifier)
      {
          return identifier.equals(AviDirectory.FORMAT);
      }
  
      public boolean shouldAcceptChunk(@NotNull String fourCC)
      {
          return fourCC.equals(AviDirectory.CHUNK_STREAM_HEADER)
              || fourCC.equals(AviDirectory.CHUNK_MAIN_HEADER)
              || fourCC.equals(AviDirectory.CHUNK_DATETIME_ORIGINAL);
      }
  
      public boolean shouldAcceptList(@NotNull String fourCC)
      {
          return fourCC.equals(AviDirectory.LIST_HEADER)
              || fourCC.equals(AviDirectory.LIST_STREAM_HEADER)
              || fourCC.equals(AviDirectory.FORMAT);
      }
  
      public void processChunk(@NotNull String fourCC, @NotNull byte[] payload)
      {
          try {
              if (fourCC.equals(AviDirectory.CHUNK_STREAM_HEADER)) {
                  ByteArrayReader reader = new ByteArrayReader(payload);
                  reader.setMotorolaByteOrder(false);
  
                  String fccType = new String(reader.getBytes(0, 4));
                  String fccHandler = new String(reader.getBytes(4, 4));
  //                int dwFlags = reader.getInt32(8);
  //                int wPriority = reader.getInt16(12);
  //                int wLanguage = reader.getInt16(14);
  //                int dwInitialFrames = reader.getInt32(16);
                  float dwScale = reader.getFloat32(20);
                  float dwRate = reader.getFloat32(24);
  //                int dwStart = reader.getInt32(28);
                  int dwLength = reader.getInt32(32);
  //                int dwSuggestedBufferSize = reader.getInt32(36);
  //                int dwQuality = reader.getInt32(40);
  //                int dwSampleSize = reader.getInt32(44);
  //                byte[] rcFrame = reader.getBytes(48, 2);
  
                  if (fccType.equals("vids")) {
                      if (!_directory.containsTag(AviDirectory.TAG_FRAMES_PER_SECOND)) {
                          _directory.setDouble(AviDirectory.TAG_FRAMES_PER_SECOND, (dwRate / dwScale));
  
                          double duration = dwLength / (dwRate / dwScale);
                          int hours = (int) duration / (int) (Math.pow(60, 2));
                          int minutes = ((int) duration / (int) (Math.pow(60, 1))) - (hours * 60);
                          int seconds = (int) Math.round((duration / (Math.pow(60, 0))) - (minutes * 60));
                          String time = String.format("%1$02d:%2$02d:%3$02d", hours, minutes, seconds);
  
                          _directory.setString(AviDirectory.TAG_DURATION, time);
                          _directory.setString(AviDirectory.TAG_VIDEO_CODEC, fccHandler);
                      }
                  } else if (fccType.equals("auds")) {
                      if (!_directory.containsTag(AviDirectory.TAG_SAMPLES_PER_SECOND)) {
                          _directory.setDouble(AviDirectory.TAG_SAMPLES_PER_SECOND, (dwRate / dwScale));
                      }
                  }
              } else if (fourCC.equals(AviDirectory.CHUNK_MAIN_HEADER)) {
                  ByteArrayReader reader = new ByteArrayReader(payload);
                  reader.setMotorolaByteOrder(false);
  
  //                int dwMicroSecPerFrame = reader.getInt32(0);
  //                int dwMaxBytesPerSec = reader.getInt32(4);
  //                int dwPaddingGranularity = reader.getInt32(8);
  //                int dwFlags = reader.getInt32(12);
  //                int dwTotalFrames = reader.getInt32(16);
  //                int dwInitialFrames = reader.getInt32(20);
                  int dwStreams = reader.getInt32(24);
  //                int dwSuggestedBufferSize = reader.getInt32(28);
                  int dwWidth = reader.getInt32(32);
                  int dwHeight = reader.getInt32(36);
  //                byte[] dwReserved = reader.getBytes(40, 4);
  
                  _directory.setInt(AviDirectory.TAG_WIDTH, dwWidth);
                  _directory.setInt(AviDirectory.TAG_HEIGHT, dwHeight);
                  _directory.setInt(AviDirectory.TAG_STREAMS, dwStreams);
              } else if (fourCC.equals(AviDirectory.CHUNK_DATETIME_ORIGINAL)) {
                  ByteArrayReader reader = new ByteArrayReader(payload);
                  String str = reader.getString(0, payload.length, "ASCII");
                  if (str.length() == 26 && str.endsWith(String.valueOf(new char[] { 0x0A, 0x00 }))) {
                      // ?0A 00? "New Line" + padded to nearest WORD boundary
                      str = str.substring(0, 24);
                  }
                  _directory.setString(AviDirectory.TAG_DATETIME_ORIGINAL, str);
              }
          } catch (IOException ex) {
              _directory.addError(ex.getMessage());
          }
      }
  
      @Override
      public void addError(@NotNull String message)
      {
          _directory.addError(message);
      }
  }
  