qudag-protocol 0.5.0

use qudag_protocol::{Coordinator, ProtocolConfig, ProtocolState, ProtocolError};
use std::time::Duration;
use tokio::time::sleep;

#[tokio::test]
async fn test_crypto_error_propagation() {
    // Test that crypto errors propagate correctly through the protocol stack
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // TODO: Test invalid signature handling
    // This would require injecting crypto errors
    let invalid_message = vec![0xff; 1000]; // Large invalid message
    let result = coordinator.broadcast_message(invalid_message).await;
    
    // Should handle the error gracefully
    match result {
        Ok(_) => {
            // Currently placeholder implementation accepts all messages
            assert!(true);
        }
        Err(ProtocolError::CryptoError(_)) => {
            // Expected behavior when crypto validation is implemented
            assert!(true);
        }
        Err(e) => {
            panic!("Unexpected error type: {:?}", e);
        }
    }
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_network_error_recovery() {
    // Test protocol recovery from network errors
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    assert_eq!(coordinator.state().await, ProtocolState::Running);
    
    // Simulate network disruption
    // TODO: Implement network failure injection
    
    // Protocol should remain in running state and recover
    assert_eq!(coordinator.state().await, ProtocolState::Running);
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_consensus_error_handling() {
    // Test protocol behavior when consensus fails
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Send messages that might cause consensus conflicts
    let conflicting_messages = vec![
        vec![1, 2, 3],
        vec![1, 2, 4], // Potential conflict
        vec![1, 2, 5], // Potential conflict
    ];
    
    for message in conflicting_messages {
        let result = coordinator.broadcast_message(message).await;
        // Should handle conflicts gracefully
        assert!(result.is_ok());
    }
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_state_transition_errors() {
    // Test error handling during state transitions
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    // Try operations before start
    let result = coordinator.broadcast_message(vec![1, 2, 3]).await;
    // Should fail or handle gracefully
    assert!(result.is_ok() || matches!(result, Err(ProtocolError::StateError(_))));
    
    coordinator.start().await.unwrap();
    
    // Operations should work after start
    let result = coordinator.broadcast_message(vec![4, 5, 6]).await;
    assert!(result.is_ok());
    
    coordinator.stop().await.unwrap();
    
    // Operations should fail after stop
    let result = coordinator.broadcast_message(vec![7, 8, 9]).await;
    // Should fail or handle gracefully
    assert!(result.is_ok() || matches!(result, Err(ProtocolError::StateError(_))));
}

#[tokio::test]
async fn test_memory_allocation_errors() {
    // Test protocol behavior under memory pressure
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Try to allocate large messages
    let large_message = vec![0u8; 10 * 1024 * 1024]; // 10MB message
    let result = coordinator.broadcast_message(large_message).await;
    
    // Should handle large messages gracefully or reject them
    match result {
        Ok(_) => {
            // Accepted large message
            assert!(true);
        }
        Err(ProtocolError::Internal(_)) => {
            // Rejected large message appropriately
            assert!(true);
        }
        Err(e) => {
            panic!("Unexpected error for large message: {:?}", e);
        }
    }
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_concurrent_error_scenarios() {
    // Test error handling under concurrent operations
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Create multiple concurrent operations
    let mut handles = Vec::new();
    
    for i in 0..10 {
        let message = vec![i as u8; 100];
        let result = coordinator.broadcast_message(message).await;
        assert!(result.is_ok());
    }
    
    // Wait for all operations to complete
    for handle in handles {
        handle.await.unwrap();
    }
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_component_failure_isolation() {
    // Test that failure in one component doesn't crash others
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Crypto component failure simulation
    // TODO: Inject crypto component failure
    
    // Network component failure simulation  
    // TODO: Inject network component failure
    
    // DAG component failure simulation
    // TODO: Inject DAG component failure
    
    // Protocol should remain stable
    assert_eq!(coordinator.state().await, ProtocolState::Running);
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_error_recovery_mechanisms() {
    // Test automatic error recovery
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Simulate recoverable error
    // TODO: Inject recoverable error
    
    // Wait for recovery
    sleep(Duration::from_millis(100)).await;
    
    // Verify recovery
    assert_eq!(coordinator.state().await, ProtocolState::Running);
    
    // Test that operations work after recovery
    let result = coordinator.broadcast_message(vec![1, 2, 3]).await;
    assert!(result.is_ok());
    
    coordinator.stop().await.unwrap();
}

#[tokio::test]
async fn test_graceful_degradation() {
    // Test graceful degradation under partial failures
    let config = ProtocolConfig::default();
    let mut coordinator = Coordinator::new(config).await.unwrap();
    
    coordinator.start().await.unwrap();
    
    // Simulate partial component failure
    // TODO: Disable specific components
    
    // Protocol should continue with reduced functionality
    assert_eq!(coordinator.state().await, ProtocolState::Running);
    
    // Some operations should still work
    let result = coordinator.broadcast_message(vec![1, 2, 3]).await;
    assert!(result.is_ok());
    
    coordinator.stop().await.unwrap();
}