$ show badoo/Chatto
Chatto is a lightweight iOS chat UI framework developed by Badoo, written in Swift. It provides a complete set of components for building chat interfaces, including a core controller (`BaseChatViewController`), a collection view layout optimized for chat, an extensible input bar, and support for various message types (text, photo, compound messages with multiple content blocks). The framework is designed around a presenter pattern where each chat item type has a dedicated presenter responsible for cell sizing, configuration, and interaction handling. It also includes a composable layout system for constructing complex bubble views. The repository includes two library targets (Chatto and ChattoAdditions) and a demo app showcasing features like pagination, swipe-to-reply, message selection, and custom input items. No backend, networking, or data persistence code is present; the demo simulates message sending. The codebase demonstrates solid architectural patterns and has reasonable test coverage, but shows signs of partial migration to a newer collection adapter, deprecated API usage (e.g., keyboard notifications), and some force unwraps. The repository has not seen active development in several years, with many open issues and stale pull requests.
The LLM identified 3 files worth highlighting for reuse:
A thread-safe observable implementation using NSLock for synchronization. Provides a simple callback-based observer pattern with a `observe` method and `value` property. Self-contained and reusable for any iOS project needing basic reactive bindings without external dependencies.
A generic serial task queue that ensures asynchronous tasks are executed one at a time, with support for cancellation and completion callbacks. Useful for managing ordered operations like network requests or animations. Well-isolated and can be extracted as a standalone utility.
A generic, thread-safe cache implementation with support for limiting size and automatic eviction. Provides subscript access and clear method. Self-contained and applicable to any iOS/macOS project needing lightweight caching without Foundation's NSCache.