--- OniSplit/Sound/WavFile.cs	2020/01/22 14:08:57	1114
+++ OniSplit/Sound/WavFile.cs	2021/05/08 01:44:24	1156
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+//using System.Runtime.Remoting.Metadata.W3cXsd2001;
 
 namespace Oni.Sound
 {
@@ -9,7 +10,8 @@ namespace Oni.Sound
         #region Private data
         private const int fcc_RIFF = 0x46464952;
         private const int fcc_WAVE = 0x45564157;
-        private const int fcc_fmt = 0x20746d66;
+        private const int fcc_fmt  = 0x20746d66;
+        private const int fcc_fact = 0x74636166;
         private const int fcc_data = 0x61746164;
 
         private WavFormat format;
@@ -18,6 +20,7 @@ namespace Oni.Sound
         private int averageBytesPerSecond;
         private int blockAlign;
         private int bitsPerSample;
+        private int sampleCount;
         private byte[] extraData;
         private byte[] soundData;
         #endregion
@@ -34,7 +37,10 @@ namespace Oni.Sound
                 if (reader.ReadInt32() != fcc_WAVE)
                     throw new InvalidDataException("Not a WAV file");
 
-                var header = new WavFile();
+                var header = new WavFile()
+                {
+                    sampleCount = -1
+                };
 
                 for (int chunkType, chunkSize, chunkStart; reader.Position < size; reader.Position = chunkStart + chunkSize)
                 {
@@ -44,10 +50,12 @@ namespace Oni.Sound
 
                     if (chunkType == fcc_fmt)
                         header.ReadFormatChunk(reader, chunkSize);
-                    else if (chunkType == fcc_data)
+                    if (chunkType == fcc_fact)
+                        header.ReadFactChunk(reader, chunkSize);
+                    if (chunkType == fcc_data)
                         header.ReadDataChunk(reader, chunkSize);
                 }
-
+                header.TruncatePerFact();
                 return header;
             }
         }
@@ -67,10 +75,39 @@ namespace Oni.Sound
                 extraData = new byte[0];
         }
 
+        private void ReadFactChunk(BinaryReader reader, int chunkSize)
+        {
+            sampleCount = reader.ReadInt32();
+        }
+
         private void ReadDataChunk(BinaryReader reader, int chunkSize)
         {
             soundData = reader.ReadBytes(chunkSize);
         }
+        private void TruncatePerFact() // TODO: MORE THOROUGH VALIDATION?
+        {
+            if(sampleCount == -1) // not explicitly set (no fact chunk present)
+            {
+                Console.WriteLine("The imported WAV file has no FACT chunk.");
+            }
+            else if (format == WavFormat.Adpcm) // calculate truncated data size
+            {
+                var blockSizeADPCM = blockAlign;
+                var samplesPerBlock = 2 + (blockSizeADPCM - channelCount * 7) * 8 / channelCount / bitsPerSample;
+                int wholeBlocks = sampleCount / samplesPerBlock;
+                if (wholeBlocks * blockAlign > soundData.Length)
+                    Console.Error.WriteLine("Sample count exceeds the range of sound data.");
+                int leftoverSamples = sampleCount - wholeBlocks * samplesPerBlock;
+                if (leftoverSamples < 2) // a block always starts with at least two samples?
+                    Console.Error.WriteLine("Improper trailing bytes/samples!");
+                if (bitsPerSample != 4) // are MS ADPCM nibbles always 4-bit-sized?
+                    Console.Error.WriteLine("Nibble size is expected to be 4 bits!");
+                int leftoverNibbles = (leftoverSamples - 2) * channelCount;
+                int leftoverBytes = 7 * channelCount
+                    + (int)Math.Ceiling((leftoverNibbles * bitsPerSample) * 0.125);
+                Array.Resize(ref soundData, wholeBlocks * blockAlign + leftoverBytes);
+            }
+        }
 
         public WavFormat Format => format;
         public int ChannelCount => channelCount;
@@ -78,6 +115,7 @@ namespace Oni.Sound
         public int AverageBytesPerSecond => averageBytesPerSecond;
         public int BlockAlign => blockAlign;
         public int BitsPerSample => bitsPerSample;
+        public int SampleCount => sampleCount;
         public byte[] ExtraData => extraData;
         public byte[] SoundData => soundData;
     }