Implement writer for the missing block types.

Yet to be tested.

src/writer.rs

@@ -48,6 +48,34 @@ fn write_sound_data_continuation(block: &BlockType) -> Vec<u8> {
     bytes
 }
 
+fn write_silence(block: &BlockType) -> Vec<u8> {
+    let mut bytes: Vec<u8> = Vec::new();
+    bytes.extend_from_slice(&[3]);
+    if let BlockType::Silence {
+        length,
+        sample_rate,
+    } = block
+    {
+        let header_size = 3;
+        bytes.extend_from_slice(&get_size(header_size));
+        bytes.extend_from_slice(&(length + 1).to_le_bytes());
+        let frequency_divisor: u8 = (256_u32 - 1000000_u32 / sample_rate) as u8;
+        bytes.extend_from_slice(&[frequency_divisor]);
+    }
+    bytes
+}
+
+fn write_marker(block: &BlockType) -> Vec<u8> {
+    let mut bytes: Vec<u8> = Vec::new();
+    bytes.extend_from_slice(&[4]);
+    if let BlockType::Marker { value } = block {
+        let header_size = 2;
+        bytes.extend_from_slice(&get_size(header_size));
+        bytes.extend_from_slice(&value.to_le_bytes());
+    }
+    bytes
+}
+
 fn write_text(block: &BlockType) -> Vec<u8> {
     let mut bytes: Vec<u8> = Vec::new();
     bytes.extend_from_slice(&[5]);
@@ -142,14 +170,13 @@ fn write_block(block: &BlockType) -> Vec<u8> {
         BlockType::Terminator => write_terminator(),
         BlockType::SoundData { .. } => write_sound_data(block),
         BlockType::SoundDataContinuation { .. } => write_sound_data_continuation(block),
-        //3 => parse_silence(input),
-        //4 => parse_marker(input),
+        BlockType::Silence { .. } => write_silence(block),
+        BlockType::Marker { .. } => write_marker(block),
         BlockType::Text { .. } => write_text(block),
         BlockType::RepeatStart { .. } => write_repeat_start(block),
         BlockType::RepeatEnd => write_repeat_end(),
         BlockType::ExtraInformation { .. } => write_extra_information(block),
         BlockType::SoundDataNew { .. } => write_sound_data_new(block),
-        _ => panic!("not implemented {:?}", block),
     }
 }