new starting with a new ebml impl

1 files changed, 48 insertions, 0 deletions

diff --git a/ebml/src/mod.rs b/ebml/src/mod.rs
new file mode 100644
index 0000000..5da6809
--- /dev/null
+++ b/ebml/src/mod.rs
@@ -0,0 +1,48 @@
+use crate::format::matroska::read::EbmlSize;
+
+use self::read::EbmlReader;
+use anyhow::{bail, Result};
+use log::debug;
+
+pub mod matroska;
+pub mod read;
+
+#[derive(Debug, Clone)]
+pub enum Master {
+    Start,
+    End,
+}
+
+#[derive(Debug, Clone)]
+pub enum MatroskaTag {
+    Ebml(Master),
+    EbmlVersion(u64),
+    EbmlReadVersion(u64),
+    EbmlMaxIdLength(u64),
+    EbmlMaxSizeLength(u64),
+    DocType(String),
+    DocTypeVersion(u64),
+    DocTypeReadVersion(u64),
+    DocTypeExtension(Master),
+}
+
+impl EbmlReader {
+    pub fn read_tag(&mut self) -> Result<MatroskaTag> {
+        let id = self.read_tag_id()?;
+        let size = EbmlSize::from_vint(self.read_vint_len()?);
+        debug!("tag id={id:x}, size={size:?}");
+        Ok(match id {
+            0x1a45dfa3 => MatroskaTag::Ebml(Master::Start),
+            0x4286 => MatroskaTag::EbmlVersion(self.read_vint()?),
+            0x42f7 => MatroskaTag::EbmlReadVersion(self.read_vint()?),
+            0x42f2 => MatroskaTag::EbmlMaxIdLength(self.read_vint()?),
+            0x42f3 => MatroskaTag::EbmlMaxSizeLength(self.read_vint()?),
+            0x4282 => MatroskaTag::DocType(self.read_utf8(size)?),
+            0x4287 => MatroskaTag::DocTypeVersion(self.read_vint()?),
+            0x4285 => MatroskaTag::DocTypeReadVersion(self.read_vint()?),
+            0x4281 => MatroskaTag::DocTypeExtension(Master::Start),
+
+            _ => bail!("thats not a tag we know..."),
+        })
+    }
+}