From a00d43e124b2d8b5c49c59e65911ef93607413c9 Mon Sep 17 00:00:00 2001
From: Tangent 128 <Tangent128@gmail.com>
Date: Sat, 1 Jul 2017 01:30:43 -0400
Subject: [PATCH] Implement decode_simple_block

---
 Cargo.toml      |  1 +
 src/bin/dump.rs |  2 +-
 src/lib.rs      |  1 +
 src/webm.rs     | 31 ++++++++++++++++++++++++++++---
 4 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 861f132..e961060 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,4 +4,5 @@ version = "0.1.0"
 authors = ["Tangent 128 <Tangent128@gmail.com>"]
 
 [dependencies]
+byteorder = "1"
 futures = "^0.1.7"
diff --git a/src/bin/dump.rs b/src/bin/dump.rs
index 1251c9a..8443dcd 100644
--- a/src/bin/dump.rs
+++ b/src/bin/dump.rs
@@ -22,7 +22,7 @@ pub fn main() {
         match element {
             // suppress printing byte arrays
             Tracks(slice) => println!("Tracks[{}]", slice.len()),
-            Cluster(slice) => println!("Cluster[{}]", slice.len()),
+            SimpleBlock{timecode, ..} => println!("SimpleBlock@{}", timecode),
             other => println!("{:?}", other)
         }
     }
diff --git a/src/lib.rs b/src/lib.rs
index f30276a..9c5fe78 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,4 +1,5 @@
 
+extern crate byteorder;
 extern crate futures;
 
 pub mod ebml;
diff --git a/src/webm.rs b/src/webm.rs
index 3908c31..75c2573 100644
--- a/src/webm.rs
+++ b/src/webm.rs
@@ -1,3 +1,4 @@
+use byteorder::{BigEndian, ByteOrder};
 use ebml::*;
 
 const SEGMENT_ID: u64 = 0x08538067;
@@ -21,7 +22,12 @@ pub enum WebmElement<'b> {
     Tracks(&'b[u8]),
     Cluster,
     Timecode(u64),
-    SimpleBlock(&'b[u8]),
+    SimpleBlock {
+        track: u64,
+        timecode: i16,
+        flags: u8,
+        data: &'b[u8]
+    },
     Unknown(u64)
 }
 
@@ -47,13 +53,32 @@ impl<'a> Schema<'a> for Webm {
             CUES_ID => Ok(WebmElement::Cues),
             TRACKS_ID => Ok(WebmElement::Tracks(bytes)),
             CLUSTER_ID => Ok(WebmElement::Cluster),
-            TIMECODE_ID => Ok(WebmElement::Timecode(0)),
-            SIMPLE_BLOCK_ID => Ok(WebmElement::SimpleBlock(bytes)),
+            TIMECODE_ID => decode_uint(bytes).map(WebmElement::Timecode),
+            SIMPLE_BLOCK_ID => decode_simple_block(bytes),
             _ => Ok(WebmElement::Unknown(element_id))
         }
     }
 }
 
+fn decode_simple_block(bytes: &[u8]) -> Result<WebmElement, Error> {
+    if let Ok(Some((Varint::Value(track), track_field_len))) = decode_varint(bytes) {
+        let header_len = track_field_len + 2 + 1;
+        if bytes.len() < header_len {
+            return Err(Error::CorruptPayload);
+        }
+        let timecode = BigEndian::read_i16(&bytes[track_field_len..]);
+        let flags = bytes[track_field_len + 2];
+        return Ok(WebmElement::SimpleBlock {
+            track: track,
+            timecode: timecode,
+            flags: flags,
+            data: &bytes[header_len..],
+        })
+    } else {
+        return Err(Error::CorruptPayload);
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use tests::TEST_FILE;