[RFC] Support using a server-side fallback for browsers without WebAssembly support

CLAUDE.md

@@ -0,0 +1,129 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Shengji is an online implementation of the Chinese trick-taking card game 升级 ("Tractor" or "Finding Friends"). It features a Rust backend with WebSocket support and a React TypeScript frontend with WebAssembly integration.
+
+## Commands
+
+### Development
+```bash
+# Run frontend in development mode with hot reloading
+cd frontend && yarn watch
+
+# Run backend in development mode
+cd backend && cargo run --features dynamic
+
+# Full development setup (run in separate terminals)
+cd frontend && yarn watch
+cd backend && cargo run --features dynamic
+```
+
+### Building
+```bash
+# Build production frontend
+cd frontend && yarn build
+
+# Build release backend
+cargo build --release
+
+# Full production build
+cd frontend && yarn build && cd ../backend && cargo run
+```
+
+### Testing
+```bash
+# Run all Rust tests
+cargo test --all
+
+# Run specific Rust test
+cargo test test_name
+
+# Run frontend tests
+cd frontend && yarn test
+
+# Run frontend tests in watch mode
+cd frontend && yarn test --watch
+```
+
+### Code Quality
+```bash
+# Lint TypeScript
+cd frontend && yarn lint
+
+# Fix TypeScript lint issues
+cd frontend && yarn lint --fix
+
+# Lint Rust
+cargo clippy
+
+# Format TypeScript
+cd frontend && yarn prettier --write
+
+# Check TypeScript formatting
+cd frontend && yarn prettier --check
+
+# Format Rust
+cargo fmt --all
+
+# Check Rust formatting
+cargo fmt --all -- --check
+```
+
+### Type Generation
+```bash
+# Generate TypeScript types from Rust schemas (run from frontend directory)
+cd frontend && yarn types && yarn prettier --write && yarn lint --fix
+```
+
+## Architecture
+
+### Rust Workspace Structure
+- **backend/**: Axum web server handling WebSocket connections and game API
+- **core/**: Game state management, message types, and serialization
+- **mechanics/**: Core game logic including bidding, tricks, and scoring
+- **storage/**: Storage abstraction layer supporting in-memory and Redis backends
+- **frontend/shengji-wasm/**: WebAssembly bindings for client-side game mechanics
+
+### Frontend Structure
+- **frontend/src/**: React components and application logic
+- **frontend/src/state/**: WebSocket connection and state management
+- **frontend/src/ChatMessage.tsx**: In-game chat implementation
+- **frontend/src/Draw.tsx**: Card rendering and game board visualization
+- **frontend/src/Play.tsx**: Main gameplay component
+- **frontend/json-schema-bin/**: Utility for generating TypeScript types from Rust
+
+### Type Safety Strategy
+The project maintains type safety between Rust and TypeScript by:
+1. Defining types in Rust using serde serialization
+2. Generating JSON schemas from Rust types
+3. Converting schemas to TypeScript definitions via json-schema-bin
+4. Sharing game logic through WebAssembly for client-side validation
+
+### WebSocket Communication
+- All game state updates flow through WebSocket connections
+- Messages are typed and validated on both client and server
+- State synchronization happens automatically via the WebSocketProvider
+
+## Development Notes
+
+### When modifying game mechanics:
+1. Update logic in `mechanics/src/`
+2. If changing message types, update `core/src/message.rs`
+3. Regenerate TypeScript types with `yarn types`
+4. Update frontend components to handle new mechanics
+
+### When adding new features:
+1. Implement server-side logic in appropriate Rust module
+2. Add message types if needed in `core/`
+3. Generate TypeScript types
+4. Implement UI in React components
+5. Ensure WebSocket message handling is updated
+
+### Testing approach:
+- Unit test game mechanics in Rust (`mechanics/src/`)
+- Integration test API endpoints in `backend/`
+- Component testing for React UI elements
+- Manual testing for WebSocket interactions and gameplay flow

Cargo.toml

@@ -2,7 +2,8 @@
 members = [
   "backend",
   "frontend/json-schema-bin",
-  "frontend/shengji-wasm"
+  "frontend/shengji-wasm",
+  "wasm-rpc-impl"
 ]
 resolver = "2"