From 7a51ed6a21d6532b3beef0b6b7973c4af88c243f Mon Sep 17 00:00:00 2001
From: kaichaosun <kaichaosuna@gmail.com>
Date: Mon, 29 Jun 2026 14:03:34 +0800
Subject: [PATCH] feat: add logos default client

---
 crates/client/src/lib.rs   |  2 ++
 crates/client/src/logos.rs | 61 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 crates/client/src/logos.rs

diff --git a/crates/client/src/lib.rs b/crates/client/src/lib.rs
index becf852..d916494 100644
--- a/crates/client/src/lib.rs
+++ b/crates/client/src/lib.rs
@@ -4,6 +4,7 @@ mod delegate;
 mod delivery_in_process;
 mod errors;
 mod event;
+mod logos;
 
 pub use builder::{ChatClientBuilder, Unset};
 pub use client::{ChatClient, Transport};
@@ -11,6 +12,7 @@ pub use delegate::DelegateSigner;
 pub use delivery_in_process::{InProcessDelivery, MessageBus};
 pub use errors::ClientError;
 pub use event::{Event, MessageSender};
+pub use logos::LogosChatClient;
 
 // Re-export types callers need to interact with ChatClient.
 pub use libchat::{
diff --git a/crates/client/src/logos.rs b/crates/client/src/logos.rs
new file mode 100644
index 0000000..152fa61
--- /dev/null
+++ b/crates/client/src/logos.rs
@@ -0,0 +1,61 @@
+//! The opinionated Logos client.
+//!
+//! [`ChatClientBuilder`] is generic and can only default the zero-config
+//! components (random identity, ephemeral registry, in-memory storage) — it has
+//! no way to know a registry endpoint or a database path, so its defaults are
+//! the test-grade ones. `LogosChatClient` is the layer that *does* commit to a
+//! stack: a delegate identity, the HTTP keypackage + account registry, and
+//! encrypted on-disk storage. It exists so independently built clients share the
+//! same production services instead of each re-deriving them.
+//!
+//! Only the transport is left to the caller: it carries native dependencies and
+//! environment-specific configuration that belong to the binary, not here.
+
+use crossbeam_channel::Receiver;
+use libchat::{ChatStorage, StorageConfig};
+
+use crate::ChatClientBuilder;
+use crate::client::{ChatClient, Transport};
+use crate::delegate::DelegateSigner;
+use crate::errors::ClientError;
+use crate::event::Event;
+use components::HttpRegistry;
+
+// The endpoint for account and keypackage registration service.
+const REGISTRY_ENDPOINT: &str = "https://devnet.chat-kc.logos.co";
+
+/// A [`ChatClient`] wired to the Logos service stack: a [`DelegateSigner`]
+/// identity, the HTTP keypackage + account registry ([`HttpRegistry`], which is
+/// both the keypackage store and the account → device directory), and encrypted
+/// [`ChatStorage`]. Only the transport `T` is supplied by the caller.
+pub type LogosChatClient<T> = ChatClient<DelegateSigner, T, HttpRegistry, ChatStorage>;
+
+impl<T> LogosChatClient<T>
+where
+    T: Transport + Send + 'static,
+{
+    /// Open a client on the Logos stack over `transport`, persisting to the
+    /// encrypted database at `db_path` unlocked with `db_key`. When `registry_url`
+    /// is `Some`, it overrides the preconfigured registry endpoint (e.g. a local
+    /// deployment); otherwise the baked-in endpoint is used.
+    ///
+    /// `db_path` is a per-client location and `db_key` is a secret, so both are
+    /// caller-supplied — never baked into the library.
+    pub fn open(
+        transport: T,
+        db_path: impl Into<String>,
+        db_key: impl Into<String>,
+        registry_url: Option<&str>,
+    ) -> Result<(Self, Receiver<Event>), ClientError> {
+        let endpoint = registry_url.unwrap_or(REGISTRY_ENDPOINT);
+        ChatClientBuilder::new()
+            .ident(DelegateSigner::random())
+            .transport(transport)
+            .registration(HttpRegistry::new(endpoint))
+            .storage_config(StorageConfig::Encrypted {
+                path: db_path.into(),
+                key: db_key.into(),
+            })
+            .build()
+    }
+}