Add encoded_len method to Encode trait. (#125)

This allows packets to calculate their exact length up front.
This isn't currently tested or being used for anything, but that will come in later changes.

Author: rj00a

Cargo.toml

@@ -40,7 +40,7 @@ sha2 = "0.10.6"
 thiserror = "1.0.35"
 url = { version = "2.2.2", features = ["serde"] }
 uuid = { version = "1.1.2", features = ["serde"] }
-valence_nbt = "0.2.0"
+valence_nbt = "0.3.0"
 vek = "0.15.8"
 
 [dependencies.tokio]

packet_inspector/src/main.rs

@@ -78,7 +78,7 @@ impl Cli {
         let len = VarInt(read.packet_buf().len() as i32);
         len.encode(&mut len_buf.as_mut_slice())?;
 
-        write.write_all(&len_buf[..len.written_size()]).await?;
+        write.write_all(&len_buf[..len.encoded_len()]).await?;
         write.write_all(read.packet_buf()).await?;
 
         pkt

src/block.rs

@@ -56,6 +56,10 @@ impl Encode for BlockState {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(self.0 as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(self.0 as i32).encoded_len()
+    }
 }
 
 impl Decode for BlockState {

src/block_pos.rs

@@ -58,6 +58,10 @@ impl Encode for BlockPos {
             _ => bail!("out of range: {self:?}"),
         }
     }
+
+    fn encoded_len(&self) -> usize {
+        8
+    }
 }
 
 impl Decode for BlockPos {

src/entity/types.rs

@@ -27,6 +27,10 @@ impl Encode for OptionalInt {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(self.0 as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(self.0 as i32).encoded_len()
+    }
 }
 
 impl Decode for OptionalInt {
@@ -54,6 +58,10 @@ impl Encode for EulerAngle {
         self.yaw.encode(w)?;
         self.roll.encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        self.pitch.encoded_len() + self.yaw.encoded_len() + self.roll.encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
@@ -70,6 +78,10 @@ impl Encode for Facing {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
@@ -105,6 +117,12 @@ impl Encode for VillagerData {
         VarInt(self.profession as i32).encode(w)?;
         VarInt(self.level).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(self.kind as i32).encoded_len()
+            + VarInt(self.profession as i32).encoded_len()
+            + VarInt(self.level).encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug)]
@@ -162,6 +180,10 @@ impl Encode for Pose {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 /// The main hand of a player.
@@ -176,6 +198,10 @@ impl Encode for MainArm {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         (*self as u8).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        1
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug)]
@@ -193,6 +219,10 @@ impl Encode for BoatKind {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug)]
@@ -215,6 +245,10 @@ impl Encode for CatKind {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug)]
@@ -229,6 +263,10 @@ impl Encode for FrogKind {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug)]
@@ -270,6 +308,10 @@ impl Encode for PaintingKind {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }
 
 // TODO
@@ -282,4 +324,8 @@ impl Encode for Particle {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         VarInt(*self as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(*self as i32).encoded_len()
+    }
 }

src/ident.rs

@@ -225,6 +225,10 @@ impl<S: Encode> Encode for Ident<S> {
     fn encode(&self, w: &mut impl Write) -> anyhow::Result<()> {
         self.string.encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        self.string.encoded_len()
+    }
 }
 
 impl<S> Decode for Ident<S>

src/item.rs

@@ -12,6 +12,10 @@ impl Encode for ItemKind {
     fn encode(&self, w: &mut impl std::io::Write) -> anyhow::Result<()> {
         VarInt(self.to_raw() as i32).encode(w)
     }
+
+    fn encoded_len(&self) -> usize {
+        VarInt(self.to_raw() as i32).encoded_len()
+    }
 }
 
 impl Decode for ItemKind {