# WSS (WebSocket Secure) Implementation Plan

## Overview
This document outlines the complete implementation plan for adding WSS support to both the server and client_ws components, with optional configuration and comprehensive examples.

## Current State Analysis

### Server (src/server)
- ✅ Basic TLS infrastructure with `rustls` and `rustls-pemfile`
- ✅ Certificate loading functionality (`load_rustls_config`)
- ✅ Optional TLS configuration in `ServerConfig`
- ✅ Existing cert.pem and key.pem files for testing
- ⚠️ TLS configuration could be enhanced with better error handling
- ⚠️ Missing WSS-specific examples and tests

### Client (src/client_ws)
- ✅ Basic TLS support with `native-tls` and `tokio-native-tls`
- ✅ Cross-platform WebSocket support (native + WASM)
- ⚠️ TLS connector accepts invalid certificates (development mode)
- ⚠️ No automatic WSS URL detection
- ⚠️ Missing WSS-specific configuration options

## Implementation Phases

### Phase 1: Server WSS Enhancement ✅ READY TO IMPLEMENT

#### 1.1 Enhanced ServerConfig
```rust
#[derive(Clone)]
pub struct ServerConfig {
    pub circle_name: String,
    pub circle_public_key: String,
    pub host: String,
    pub port: u16,
    pub redis_url: String,
    pub enable_auth: bool,
    
    // Enhanced TLS Configuration
    pub enable_tls: bool,           // Explicit TLS enable flag
    pub cert_path: Option<String>,  // Path to certificate file
    pub key_path: Option<String>,   // Path to private key file
    pub tls_port: Option<u16>,      // Optional separate TLS port
    pub tls_accept_invalid_certs: bool, // For development
}
```

#### 1.2 Improved TLS Loading
- Better error messages for certificate loading failures
- Validation of certificate and key file existence
- Support for different certificate formats
- Logging of TLS configuration status

#### 1.3 Enhanced spawn_circle_server
- Clear logging of HTTP vs HTTPS mode
- Better error handling for TLS configuration
- Support for running both HTTP and HTTPS simultaneously (if needed)

### Phase 2: Client WSS Enhancement

#### 2.1 WSS URL Detection
```rust
impl CircleWsClient {
    fn is_wss_url(&self) -> bool {
        self.ws_url.starts_with("wss://")
    }
    
    fn requires_tls(&self) -> bool {
        self.is_wss_url()
    }
}
```

#### 2.2 Enhanced TLS Configuration
```rust
pub struct TlsConfig {
    pub accept_invalid_certs: bool,
    pub accept_invalid_hostnames: bool,
    pub ca_cert_path: Option<String>,
    pub client_cert_path: Option<String>,
    pub client_key_path: Option<String>,
}

impl CircleWsClientBuilder {
    pub fn with_tls_config(mut self, tls_config: TlsConfig) -> Self {
        self.tls_config = Some(tls_config);
        self
    }
}
```

#### 2.3 Cross-Platform WSS Support
- Native: Enhanced `tokio-tungstenite` with `rustls` support
- WASM: Ensure `gloo-net` handles WSS URLs correctly
- Consistent error handling across platforms

### Phase 3: Examples and Testing

#### 3.1 Basic WSS Example
```rust
// examples/wss_basic_example.rs
// Demonstrates basic WSS connection without authentication
```

#### 3.2 WSS + Authentication Example
```rust
// examples/wss_auth_example.rs
// Demonstrates WSS connection with secp256k1 authentication
```

#### 3.3 End-to-End Secure Example
```rust
// examples/wss_end_to_end_example.rs
// Complete server + client WSS with authentication
```

#### 3.4 Certificate Generation Helper
```rust
// examples/wss_cert_generation.rs
// Helper to generate self-signed certificates for development
```

### Phase 4: Documentation and Integration

#### 4.1 Update README files
- Server WSS configuration guide
- Client WSS usage examples
- Certificate management instructions

#### 4.2 Integration Tests
- WSS connection establishment
- WSS + authentication flow
- Certificate validation scenarios

## Technical Implementation Details

### Server Enhancements

#### Enhanced Certificate Loading
```rust
fn load_rustls_config(
    cert_path: &str,
    key_path: &str,
) -> Result<RustlsServerConfig, TlsConfigError> {
    // Validate file existence
    if !std::path::Path::new(cert_path).exists() {
        return Err(TlsConfigError::CertificateNotFound(cert_path.to_string()));
    }
    
    if !std::path::Path::new(key_path).exists() {
        return Err(TlsConfigError::PrivateKeyNotFound(key_path.to_string()));
    }
    
    // Enhanced error handling for certificate loading
    // Support for different key formats (PKCS8, RSA, etc.)
    // Validation of certificate chain
}
```

#### TLS Error Types
```rust
#[derive(Error, Debug)]
pub enum TlsConfigError {
    #[error("Certificate file not found: {0}")]
    CertificateNotFound(String),
    #[error("Private key file not found: {0}")]
    PrivateKeyNotFound(String),
    #[error("Invalid certificate format: {0}")]
    InvalidCertificate(String),
    #[error("Invalid private key format: {0}")]
    InvalidPrivateKey(String),
    #[error("TLS configuration error: {0}")]
    ConfigurationError(String),
}
```

### Client Enhancements

#### WSS Connection Logic
```rust
impl CircleWsClient {
    async fn create_tls_connector(&self) -> Result<TlsConnector, CircleWsClientError> {
        let mut builder = TlsConnector::builder();
        
        if let Some(tls_config) = &self.tls_config {
            builder.danger_accept_invalid_certs(tls_config.accept_invalid_certs);
            builder.danger_accept_invalid_hostnames(tls_config.accept_invalid_hostnames);
            
            // Load custom CA certificates if provided
            if let Some(ca_cert_path) = &tls_config.ca_cert_path {
                // Load and add CA certificate
            }
        }
        
        builder.build().map_err(|e| {
            CircleWsClientError::ConnectionError(format!("TLS configuration failed: {}", e))
        })
    }
}
```

### Example Structure

#### Basic WSS Example
```rust
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Start WSS server
    let config = ServerConfig {
        enable_tls: true,
        cert_path: Some("cert.pem".to_string()),
        key_path: Some("key.pem".to_string()),
        port: 8443,
        // ... other config
    };
    
    let (server_task, _handle) = spawn_circle_server(config)?;
    
    // Connect WSS client
    let mut client = CircleWsClientBuilder::new("wss://localhost:8443/ws".to_string())
        .with_tls_config(TlsConfig {
            accept_invalid_certs: true, // For development
            ..Default::default()
        })
        .build();
    
    client.connect().await?;
    
    // Test basic functionality
    let result = client.play("print('Hello WSS!')".to_string()).await?;
    println!("Result: {}", result.output);
    
    client.disconnect().await;
    Ok(())
}
```

#### WSS + Authentication Example
```rust
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Start authenticated WSS server
    let config = ServerConfig {
        enable_tls: true,
        enable_auth: true,
        cert_path: Some("cert.pem".to_string()),
        key_path: Some("key.pem".to_string()),
        port: 8443,
        // ... other config
    };
    
    // Connect authenticated WSS client
    let private_key = "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef";
    
    let mut client = CircleWsClientBuilder::new("wss://localhost:8443/ws".to_string())
        .with_keypair(private_key.to_string())
        .with_tls_config(TlsConfig {
            accept_invalid_certs: true,
            ..Default::default()
        })
        .build();
    
    client.connect().await?;
    
    // Authenticate over secure connection
    match client.authenticate().await? {
        true => println!("Authenticated successfully over WSS"),
        false => println!("Authentication failed"),
    }
    
    // Test authenticated request over secure connection
    let result = client.play("print('Authenticated WSS request!')".to_string()).await?;
    println!("Secure result: {}", result.output);
    
    client.disconnect().await;
    Ok(())
}
```

## Testing Strategy

### Unit Tests
- TLS configuration validation
- Certificate loading error handling
- WSS URL detection
- TLS connector creation

### Integration Tests
- WSS server startup with valid certificates
- WSS client connection establishment
- WSS + authentication flow
- Error scenarios (invalid certificates, connection failures)

### End-to-End Tests
- Complete WSS server + client communication
- Authentication over WSS
- Multiple concurrent WSS connections
- Certificate validation scenarios

## Security Considerations

### Development vs Production
- **Development**: Accept self-signed certificates, invalid hostnames
- **Production**: Strict certificate validation, proper CA chains

### Certificate Management
- Clear documentation for certificate generation
- Support for Let's Encrypt certificates
- Certificate rotation considerations

### TLS Configuration
- Modern TLS versions (1.2+)
- Secure cipher suites
- HSTS headers for web clients

## File Changes Required

### New Files
- `examples/wss_basic_example.rs`
- `examples/wss_auth_example.rs`
- `examples/wss_end_to_end_example.rs`
- `examples/wss_cert_generation.rs`
- `src/server/src/tls_config.rs` (optional)
- `src/client_ws/src/tls_config.rs` (optional)

### Modified Files
- `src/server/src/lib.rs` - Enhanced TLS support
- `src/server/cmd/main.rs` - TLS CLI options
- `src/client_ws/src/lib.rs` - WSS support
- `src/client_ws/Cargo.toml` - Additional TLS dependencies
- `src/server/Cargo.toml` - Enhanced TLS dependencies
- `src/server/README.md` - WSS documentation
- `src/client_ws/README.md` - WSS usage guide

## Dependencies

### Server Additional Dependencies
```toml
# Enhanced TLS support
rustls-webpki = "0.103"
rustls-native-certs = "0.7"
```

### Client Additional Dependencies
```toml
# Enhanced TLS support for native
rustls = { version = "0.23", optional = true }
tokio-rustls = { version = "0.26", optional = true }
rustls-native-certs = { version = "0.7", optional = true }

[features]
default = ["crypto"]
crypto = ["secp256k1", "sha3"]
rustls-tls = ["rustls", "tokio-rustls", "rustls-native-certs"]
```

## Implementation Order

1. **Phase 1a**: Enhance server TLS configuration and error handling
2. **Phase 1b**: Create basic WSS server example and test
3. **Phase 1c**: Validate server WSS functionality with manual testing
4. **Phase 2a**: Enhance client WSS support
5. **Phase 2b**: Create client WSS examples
6. **Phase 2c**: Test client WSS connectivity
7. **Phase 3**: Create end-to-end WSS examples
8. **Phase 4**: Integration tests and documentation

## Success Criteria

- ✅ Server can start with WSS enabled using existing certificates
- ✅ Client can connect to WSS server with proper TLS validation
- ✅ Authentication works over WSS connections
- ✅ Examples demonstrate all WSS functionality
- ✅ Tests validate WSS behavior
- ✅ Documentation explains WSS configuration
- ✅ Cross-platform compatibility (native + WASM)

## Next Steps

1. Switch to Code mode for implementation
2. Start with Phase 1a: Server TLS enhancements
3. Create and test basic WSS server example
4. Validate functionality before proceeding to client