From e4fc4732b55f0387f2a754ad4bed1354657ad2e6 Mon Sep 17 00:00:00 2001
From: Jamie Hardt <jamiehardt@me.com>
Date: Fri, 25 Dec 2020 20:55:38 -0800
Subject: [PATCH] Wavewriter impl

---
 src/common_format.rs | 10 +++++-----
 src/fmt.rs           | 14 ++++++++++++--
 src/wavewriter.rs    | 19 +++++++++++++++----
 3 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/common_format.rs b/src/common_format.rs
index 211774d..72ee11b 100644
--- a/src/common_format.rs
+++ b/src/common_format.rs
@@ -22,19 +22,19 @@ const BASIC_EXTENDED: u16   = 0xFFFE;
 
 */
 
-const UUID_PCM: Uuid =           Uuid::from_bytes([0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 
+pub const UUID_PCM: Uuid =           Uuid::from_bytes([0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71]);
 
-const UUID_FLOAT: Uuid =         Uuid::from_bytes([0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
+pub const UUID_FLOAT: Uuid =         Uuid::from_bytes([0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71]);
 
-const UUID_MPEG: Uuid =          Uuid::from_bytes([0x50, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
+pub const UUID_MPEG: Uuid =          Uuid::from_bytes([0x50, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71]);
 
-const UUID_BFORMAT_PCM: Uuid =   Uuid::from_bytes([0x01, 0x00, 0x00, 0x00, 0x21, 0x07, 0xd3, 0x11, 
+pub const UUID_BFORMAT_PCM: Uuid =   Uuid::from_bytes([0x01, 0x00, 0x00, 0x00, 0x21, 0x07, 0xd3, 0x11, 
     0x86, 0x44, 0xc8, 0xc1, 0xca, 0x00, 0x00, 0x00]);
 
-const UUID_BFORMAT_FLOAT: Uuid = Uuid::from_bytes([0x03, 0x00, 0x00, 0x00, 0x21, 0x07, 0xd3, 0x11,
+pub const UUID_BFORMAT_FLOAT: Uuid = Uuid::from_bytes([0x03, 0x00, 0x00, 0x00, 0x21, 0x07, 0xd3, 0x11,
     0x86, 0x44, 0xc8, 0xc1, 0xca, 0x00, 0x00, 0x00]);
 
 
diff --git a/src/fmt.rs b/src/fmt.rs
index b4ab4a8..465c8f0 100644
--- a/src/fmt.rs
+++ b/src/fmt.rs
@@ -1,5 +1,5 @@
 use uuid::Uuid;
-use super::common_format::CommonFormat;
+use super::common_format::{CommonFormat, UUID_PCM};
 
 #[allow(dead_code)]
 
@@ -200,7 +200,17 @@ impl WaveFmt {
             bytes_per_second: container_bytes_per_sample as u32 * sample_rate * channel_count as u32,
             block_alignment: container_bytes_per_sample * channel_count,
             bits_per_sample: container_bits_per_sample,
-            extended_format: None
+            extended_format: {
+                if channel_count > 2 {
+                    Some( WaveFmtExtended {
+                        channel_mask : !(0xFFFF_FFFF << channel_count),
+                        type_guid: UUID_PCM,
+                        valid_bits_per_sample: bits_per_sample
+                    })
+                } else {
+                    None
+                }
+            }
         }
     }
 
diff --git a/src/wavewriter.rs b/src/wavewriter.rs
index a4a5964..6876182 100644
--- a/src/wavewriter.rs
+++ b/src/wavewriter.rs
@@ -2,8 +2,9 @@ use std::fs::File;
 use std::io::{Write,Seek,SeekFrom};
 
 use super::Error;
-use super::fourcc::{FourCC, WriteFourCC, RIFF_SIG, WAVE_SIG, FMT__SIG,};
+use super::fourcc::{FourCC, WriteFourCC, RIFF_SIG, WAVE_SIG, FMT__SIG,FACT_SIG};
 use super::fmt::WaveFmt;
+use super::common_format::CommonFormat;
 use super::chunks::WriteBWaveChunks;
 
 use byteorder::LittleEndian;
@@ -66,7 +67,9 @@ impl<W> Write for WaveChunkWriter<W> where W: Write + Seek {
 pub struct WaveWriter<W> where W: Write + Seek {
     inner : W,
     form_length: u64,
-    format: WaveFmt
+
+    /// Format of the wave file.
+    pub format: WaveFmt
 }
 
 impl WaveWriter<File> {
@@ -97,7 +100,14 @@ impl<W> WaveWriter<W> where W: Write + Seek {
         chunk.write_wave_fmt(&format)?;
         let retval = chunk.end();
 
-        Ok( retval )
+        if format.common_format() != CommonFormat::IntegerPCM {
+            let mut chunk = retval.begin_chunk(FACT_SIG)?;
+            chunk.write_u32::<LittleEndian>(0)?;
+            let retval = chunk.end();
+            Ok( retval )
+        } else {
+            Ok( retval )
+        }
     }
 
     /// Create a new chunk writer, which takes posession of the `WaveWriter`.
@@ -135,4 +145,5 @@ fn test_new() {
     let fmt_size = cursor.read_u32::<LittleEndian>().unwrap();
     assert_eq!(form_size, fmt_size + 8 + 4);
 
-}
\ No newline at end of file
+}
+