Add FFI functions for send_content and handle_payload (#29)

* Add api calls for handle_payload and send_content

* Add handle_payload and send_content to FFI

conversations/src/api.rs

@@ -12,7 +12,7 @@ pub enum ErrorCode {
     UnknownError = -6,
 }
 
-use crate::context::{Context, Introduction};
+use crate::context::{Context, ConvoHandle, Introduction};
 
 /// Opaque wrapper for Context
 #[derive_ReprC]
@@ -101,6 +101,69 @@ pub fn create_new_private_convo(
     }
 }
 
+/// Sends content to an existing conversation
+///
+/// # Returns
+/// Returns a PayloadResult with payloads that must be delivered to participants.
+/// Check error_code field: 0 means success, negative values indicate errors (see ErrorCode).
+#[ffi_export]
+pub fn send_content(
+    ctx: &mut ContextHandle,
+    convo_handle: ConvoHandle,
+    content: c_slice::Ref<'_, u8>,
+) -> PayloadResult {
+    let payloads = ctx.0.send_content(convo_handle, &content);
+
+    let ffi_payloads: Vec<Payload> = payloads
+        .into_iter()
+        .map(|p| Payload {
+            address: p.delivery_address.into(),
+            data: p.data.into(),
+        })
+        .collect();
+
+    PayloadResult {
+        error_code: 0,
+        payloads: ffi_payloads.into(),
+    }
+}
+
+/// Handles an incoming payload and writes content to caller-provided buffers
+///
+/// # Returns
+/// Returns the number of bytes written to data_out on success (>= 0).
+/// Returns negative error code on failure (see ErrorCode).
+/// conversation_id_out_len is set to the number of bytes written to conversation_id_out.
+#[ffi_export]
+pub fn handle_payload(
+    ctx: &mut ContextHandle,
+    payload: c_slice::Ref<'_, u8>,
+    mut conversation_id_out: c_slice::Mut<'_, u8>,
+    conversation_id_out_len: Out<'_, u32>,
+    mut content_out: c_slice::Mut<'_, u8>,
+) -> i32 {
+    match ctx.0.handle_payload(&payload) {
+        Some(content) => {
+            let convo_id_bytes = content.conversation_id.as_bytes();
+
+            if conversation_id_out.len() < convo_id_bytes.len() {
+                return ErrorCode::BufferExceeded as i32;
+            }
+
+            if content_out.len() < content.data.len() {
+                return ErrorCode::BufferExceeded as i32;
+            }
+
+            conversation_id_out[..convo_id_bytes.len()].copy_from_slice(convo_id_bytes);
+            conversation_id_out_len.write(convo_id_bytes.len() as u32);
+            content_out[..content.data.len()].copy_from_slice(&content.data);
+
+            content.data.len() as i32
+        }
+        None => 0,
+    }
+}
+
 // ============================================================================
 // safer_ffi implementation
 // ===============================================================================================================================

conversations/src/context.rs

@@ -14,7 +14,7 @@ pub use crate::inbox::Introduction;
 const INITIAL_CONVO_HANDLE: u32 = 0xF5000001;
 
 /// Used to identify a conversation on the othersize of the FFI.
-type ConvoHandle = u32;
+pub type ConvoHandle = u32;
 
 // This is the main entry point to the conversations api.
 // Ctx manages lifetimes of objects to process and generate payloads.
@@ -63,10 +63,10 @@ impl Context {
         (convo_handle, payloads)
     }
 
-    pub fn send_content(&mut self, _convo_id: ConversationId, _content: &[u8]) -> Vec<PayloadData> {
+    pub fn send_content(&mut self, convo_id: ConvoHandle, _content: &[u8]) -> Vec<PayloadData> {
         // !TODO Replace Mock
         vec![PayloadData {
-            delivery_address: _convo_id.into(),
+            delivery_address: format!("addr-for-{convo_id}"),
             data: vec![40, 30, 20, 10],
         }]
     }

conversations/src/lib.rs

@@ -30,18 +30,64 @@ mod tests {
             bundle.set_len(bundle_len as usize);
         }
 
+        assert!(bundle_len > 0, "bundle failed: {}", bundle_len);
+        let content = b"Hello";
+        let result = create_new_private_convo(&mut ctx, bundle[..].into(), content[..].into());
+
+        assert!(result.error_code == 0, "Error: {}", result.error_code);
+
+        destroy_context(ctx);
+    }
+
+    #[test]
+    fn test_message_roundtrip() {
+        let mut saro = create_context();
+        let mut raya = create_context();
+        let mut raya_bundle = vec![0u8; 200];
+
+        let bundle_len = create_intro_bundle(&mut raya, (&mut raya_bundle[..]).into());
+        unsafe {
+            raya_bundle.set_len(bundle_len as usize);
+        }
+
         assert!(bundle_len > 0, "bundle failed: {}", bundle_len);
         let content = String::from_str("Hello").unwrap();
         let result = create_new_private_convo(
-            &mut ctx,
+            &mut saro,
-            bundle.as_slice().into(),
+            raya_bundle.as_slice().into(),
             content.as_bytes().into(),
         );
 
         assert!(result.error_code == 0, "Error: {}", result.error_code);
 
-        println!(" ID:{:?}   Payloads:{:?}", result.convo_id, result.payloads);
+        // Handle payloads on raya's side
+        let mut conversation_id_out = vec![0u8; 256];
+        let mut conversation_id_out_len: u32 = 0;
+        let mut content_out = vec![0u8; 256];
 
-        destroy_context(ctx);
+        for p in result.payloads.iter() {
+            let bytes_written = handle_payload(
+                &mut raya,
+                p.data[..].into(),
+                (&mut conversation_id_out[..]).into(),
+                (&mut conversation_id_out_len).into(),
+                (&mut content_out[..]).into(),
+            );
+
+            unsafe {
+                content_out.set_len(bytes_written as usize);
+            }
+
+            assert!(
+                bytes_written >= 0,
+                "handle_payload failed: {}",
+                bytes_written
+            );
+
+            //TODO: Verify output match
+        }
+
+        destroy_context(saro);
+        destroy_context(raya);
     }
 }

nim-bindings/examples/pingpong.nim

@@ -1,3 +1,4 @@
+import options
 import results
 
 import ../src/libchat
@@ -12,11 +13,23 @@ proc pingpong() =
   let intro = raya.createIntroductionBundle().expect("[Raya] Couldn't create intro bundle")
   echo "Raya's Intro Bundle: ",intro
 
-  var (convo_sr, payload) = saro.createNewPrivateConvo(intro,"Hey Raya").expect("[Saro] Couldn't create convo")
+  var (convo_sr, payloads) = saro.createNewPrivateConvo(intro, "Hey Raya").expect("[Saro] Couldn't create convo")
   echo "ConvoHandle::  ", convo_sr
-  echo "Payload::      ", payload
+  echo "Payload::      ", payloads
-  
 
+  ## Send Payloads to Raya
+  for p in payloads:
+    let res = raya.handlePayload(p.data)
+    if res.isOk:
+      let opt = res.get()
+      if opt.isSome:
+        let content_result = opt.get()
+        echo "RecvContent: ", content_result.conversationId, " ", content_result.data
+    else:
+      echo "Failed to handle payload: ", res.error
+
+  echo "Done"
 
 when isMainModule:
   pingpong()
+

nim-bindings/src/bindings.nim

@@ -107,6 +107,26 @@ proc create_new_private_convo*(
   content: SliceUint8,
 ): NewConvoResult {.importc, dynlib: CONVERSATIONS_LIB.}
 
+## Sends content to an existing conversation
+## Returns: PayloadResult struct - check error_code field (0 = success, negative = error)
+## The result must be freed with destroy_payload_result()
+proc send_content*(
+  ctx: ContextHandle,
+  convo_handle: ConvoHandle,
+  content: SliceUint8,
+): PayloadResult {.importc, dynlib: CONVERSATIONS_LIB.}
+
+## Handles an incoming payload and writes content to caller-provided buffers
+## Returns: Number of bytes written to content_out on success (>= 0), negative error code on failure
+## conversation_id_out_len is set to the number of bytes written to conversation_id_out
+proc handle_payload*(
+  ctx: ContextHandle,
+  payload: SliceUint8,
+  conversation_id_out: SliceUint8,
+  conversation_id_out_len: ptr uint32,
+  content_out: SliceUint8,
+): int32 {.importc, dynlib: CONVERSATIONS_LIB.}
+
 ## Free the result from create_new_private_convo
 proc destroy_convo_result*(result: NewConvoResult) {.importc, dynlib: CONVERSATIONS_LIB.}
 

nim-bindings/src/libchat.nim

@@ -1,3 +1,4 @@
+import std/options
 import results
 import bindings
 
@@ -81,6 +82,76 @@ proc createNewPrivateConvo*(ctx: LibChat, bundle: string, content: string): Resu
 
   return ok((convoId, payloads))
 
+## Send content to an existing conversation
+proc sendContent*(ctx: LibChat, convoHandle: ConvoHandle, content: string): Result[seq[PayloadResult], string] =
+  if ctx.handle == nil:
+    return err("Context handle is nil")
+
+  if content.len == 0:
+    return err("content is zero length")
+
+  let res = bindings.send_content(
+    ctx.handle,
+    convoHandle,
+    content.toSlice()
+  )
+
+  if res.error_code != 0:
+    result = err("Failed to send content: " & $res.error_code)
+    destroy_payload_result(res)
+    return
+
+  # Convert payloads to Nim types
+  var payloads = newSeq[PayloadResult](res.payloads.len)
+  for i in 0 ..< res.payloads.len:
+    let p = res.payloads[int(i)]
+    payloads[int(i)] = PayloadResult(
+      address: $p.address,
+      data: p.data.toSeq()
+    )
+
+  destroy_payload_result(res)
+  return ok(payloads)
+
+type
+  ContentResult* = object
+    conversationId*: string
+    data*: seq[uint8]
+
+## Handle an incoming payload and decrypt content
+proc handlePayload*(ctx: LibChat, payload: seq[byte]): Result[Option[ContentResult], string] =
+  if ctx.handle == nil:
+    return err("Context handle is nil")
+
+  if payload.len == 0:
+    return err("payload is zero length")
+
+  var conversationIdBuf = newSeq[byte](ctx.buffer_size)
+  var contentBuf = newSeq[byte](ctx.buffer_size)
+  var conversationIdLen: uint32 = 0
+
+  let bytesWritten = bindings.handle_payload(
+    ctx.handle,
+    payload.toSlice(),
+    conversationIdBuf.toSlice(),
+    addr conversationIdLen,
+    contentBuf.toSlice()
+  )
+
+  if bytesWritten < 0:
+    return err("Failed to handle payload: " & $bytesWritten)
+
+  if bytesWritten == 0:
+    return ok(none(ContentResult))
+
+  conversationIdBuf.setLen(conversationIdLen)
+  contentBuf.setLen(bytesWritten)
+
+  return ok(some(ContentResult(
+    conversationId: cast[string](conversationIdBuf),
+    data: contentBuf
+  )))
+
 
 proc `=destroy`(x: var LibChat) =
   # Automatically free handle when the destructor is called