feat: ListConversations (#60)

* Add function to get available conversations_ids

* Update bindings

* linter fix

* remove dynlib reference

* destructor fix

conversations/src/api.rs

@@ -139,6 +139,29 @@ pub fn create_new_private_convo(
     };
 }
 
+/// List existing conversations
+///
+/// # Returns
+/// Returns a struct with conversation ids of available conversations
+/// The ListConvoResult must be freed.
+#[ffi_export]
+pub fn list_conversations(ctx: &mut ContextHandle) -> ListConvoResult {
+    match ctx.0.list_conversations() {
+        Ok(ids) => {
+            let ffi_ids: Vec<repr_c::String> =
+                ids.into_iter().map(|id| id.to_string().into()).collect();
+            ListConvoResult {
+                error_code: ErrorCode::None as i32,
+                convo_ids: ffi_ids.into(),
+            }
+        }
+        Err(_) => ListConvoResult {
+            error_code: ErrorCode::UnknownError as i32,
+            convo_ids: repr_c::Vec::EMPTY,
+        },
+    }
+}
+
 /// Sends content to an existing conversation
 ///
 /// # Returns
@@ -330,3 +353,18 @@ pub struct NewConvoResult {
 pub fn destroy_convo_result(result: &mut NewConvoResult) {
     unsafe { std::ptr::drop_in_place(result) }
 }
+
+/// Result structure for create_new_private_convo
+/// error_code is 0 on success, negative on error (see ErrorCode)
+#[derive_ReprC]
+#[repr(C)]
+pub struct ListConvoResult {
+    pub error_code: i32,
+    pub convo_ids: repr_c::Vec<repr_c::String>,
+}
+
+/// Free the result from create_new_private_convo
+#[ffi_export]
+pub fn destroy_list_result(result: ListConvoResult) {
+    drop(result);
+}

conversations/src/context.rs

@@ -55,6 +55,10 @@ impl Context {
         (convo_id, payload_bytes)
     }
 
+    pub fn list_conversations(&self) -> Result<Vec<ConversationIdOwned>, ChatError> {
+        Ok(self.store.conversation_ids())
+    }
+
     pub fn send_content(
         &mut self,
         convo_id: ConversationId,

nim-bindings/src/bindings.nim

@@ -42,6 +42,12 @@ type
     len*: csize_t
     cap*: csize_t
 
+    ## Vector of Payloads returned by safer_ffi functions
+  VecString* = object
+    `ptr`*: ptr ReprCString
+    len*: csize_t
+    cap*: csize_t
+
   ## Result structure for create_intro_bundle
   ## error_code is 0 on success, negative on error (see ErrorCode)
   CreateIntroResult* = object
@@ -69,6 +75,12 @@ type
     convo_id*: ReprCString
     payloads*: VecPayload
 
+  ## Result from list_conversations
+  ## error_code is 0 on success, negative on error (see ErrorCode)
+  ListConvoResult* = object
+    error_code*: int32
+    convo_ids*: VecString
+
 # FFI function imports
 
 ## Creates a new libchat Context
@@ -100,6 +112,13 @@ proc create_new_private_convo*(
   content: SliceUint8,
 ): NewConvoResult {.importc.}
 
+## Get the available conversation identifers.
+## Returns: ListConvoResult struct - check error_code field (0 = success, negative = error)
+## The result must be freed with destroy_list_result()
+proc list_conversations*(
+  ctx: ContextHandle,
+): ListConvoResult {.importc.}
+
 ## Sends content to an existing conversation
 ## Returns: SendContentResult struct - check error_code field (0 = success, negative = error)
 ## The result must be freed with destroy_send_content_result()
@@ -125,6 +144,9 @@ proc destroy_intro_result*(result: CreateIntroResult) {.importc.}
 ## Free the result from create_new_private_convo
 proc destroy_convo_result*(result: NewConvoResult) {.importc.}
 
+## Free the result from list_conversation
+proc destroy_list_result*(result: ListConvoResult) {.importc.}
+
 ## Free the result from send_content
 proc destroy_send_content_result*(result: SendContentResult) {.importc.}
 
@@ -166,6 +188,15 @@ proc toReprCString*(s: string): ReprCString =
   else:
     ReprCString(`ptr`: cast[ptr char](unsafeAddr s[0]), len: csize_t(s.len), cap: 0)
 
+## Convert a VecUint8 to a seq[string]
+proc toSeq*(v: VecString): seq[string] =
+  if v.ptr == nil or v.len == 0:
+    return @[]
+  result = newSeq[string](v.len)
+  let arr = cast[ptr UncheckedArray[ReprCString]](v.ptr)
+  for i in 0 ..< int(v.len):
+    result[i] = $arr[i]
+
 ## Convert a VecUint8 to a seq[byte]
 proc toSeq*(v: VecUint8): seq[byte] =
   if v.ptr == nil or v.len == 0:
@@ -193,3 +224,4 @@ proc toBytes*(s: string): seq[byte] =
     return @[]
   result = newSeq[byte](s.len)
   copyMem(addr result[0], unsafeAddr s[0], s.len)
+

nim-bindings/src/libchat.nim

@@ -74,6 +74,18 @@ proc createNewPrivateConvo*(ctx: LibChat, bundle: seq[byte], content: seq[byte])
 
   return ok(($res.convo_id, payloads))
 
+proc listConversations*(ctx: LibChat): Result[seq[string], string] =
+  if ctx.handle == nil:
+    return err("Context handle is nil")
+  let res = bindings.list_conversations(ctx.handle)
+
+  if res.error_code != 0:
+    result = err("Failed to list conversations: " & $res.error_code)
+    destroy_list_result(res)
+    return
+
+  ok(res.convo_ids.toSeq())
+
 ## Send content to an existing conversation
 proc sendContent*(ctx: LibChat, convoId: string, content: seq[byte]): Result[seq[PayloadResult], string] =
   if ctx.handle == nil: