From 89f9e4565abc46c99064e6283e71a3ff381d8383 Mon Sep 17 00:00:00 2001
From: Wesley Moore <wes@wezm.net>
Date: Sun, 21 Jan 2024 21:36:19 +1000
Subject: [PATCH] WIP

---
 src/lib.rs | 62 ++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 55 insertions(+), 7 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index f846950..f87f5e2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,8 +1,8 @@
 use std::io;
 
 use esphome_proto::api::HelloRequest;
-use esphome_proto::protobuf::{CodedOutputStream, MessageFull};
-use smol::io::{AsyncWrite, AsyncWriteExt};
+use esphome_proto::protobuf::{CodedInputStream, CodedOutputStream, MessageFull};
+use smol::io::{AsyncAsSync, AsyncRead, AsyncWrite, AsyncWriteExt};
 use smol::net::{AsyncToSocketAddrs, TcpStream};
 
 struct Client {
@@ -33,17 +33,22 @@ impl Connection {
             api_version_minor: 0,
             special_fields: Default::default(),
         };
+        Self::send_message(hello, &mut stream).await?;
+
+        // Read response
+
+        // Login + read response
 
         Ok(Connection { stream })
     }
 
-    async fn send_message<M: MessageFull, W: AsyncWrite>(
-        message: M,
-        stream: &mut W,
-    ) -> Result<(), io::Error> {
+    async fn send_message<M, W>(message: M, stream: &mut W) -> Result<(), io::Error>
+    where
+        M: MessageFull,
+        W: AsyncWrite + Unpin,
+    {
         let mut buf = Vec::new();
         let mut out = CodedOutputStream::vec(&mut buf);
-        // let message_bytes = message.write_to_bytes()?;
         let id_option = esphome_proto::api_options::exts::id;
         let id = M::descriptor()
             .proto()
@@ -62,4 +67,47 @@ impl Connection {
         drop(out);
         stream.write_all(&buf).await
     }
+
+    /// Receive a specific message type
+    async fn receive_message<M, R>(stream: &mut R) -> Result<(), io::Error>
+        where
+            M: MessageFull,
+            R: AsyncRead
+    {
+        let mut buf = Vec::new();
+
+        let reader = AsyncAsSync::new(context, stream);
+        let mut ins= CodedInputStream::new(reader);
+
+        let id_option = esphome_proto::api_options::exts::id;
+        let id = M::descriptor()
+            .proto()
+            .options
+            .as_ref()
+            .and_then(|options| id_option.get(options))
+            .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "message is missing id"))?;
+        // let len = u32::try_from(message.compute_size())
+        //     .map_err(|err| io::Error::new(io::ErrorKind::Other, err))?;
+
+        let zero = ins.read_raw_byte()?;
+        // TODO: Handle WouldBlock
+        if zero != 0 {
+            return Err(io::Error::new(io::ErrorKind::Other, format!("expected zero got: {zero}")));
+        }
+        // TODO: Handle WouldBlock
+        let len = ins.read_raw_varint32()?;
+        // TODO: Handle WouldBlock
+        let message_id = ins.read_raw_varint32()?;
+        if message_id != id {
+            return Err(io::Error::new(io::ErrorKind::Other, format!("expected message id {id} got {message_id}")));
+        }
+
+        let msg = ins.read_message()?;
+        Ok(msg)
+
+        // message.write_to_with_cached_sizes(&mut out)?;
+        // out.flush()?;
+        // drop(out);
+        // stream.write_all(&buf).await
+    }
 }