# Task 3 — Wire ExecutionCircuitBreaker

**Priority:** HIGH  
**Estimated time:** 1.5–2 hours  
**Depends on:** Task 1 (NT8StrategyBase changes)  
**Status:** TODO

---

## Problem

`ExecutionCircuitBreaker` in `src/NT8.Core/Execution/ExecutionCircuitBreaker.cs` is a complete, well-tested class.  
It is never instantiated or connected to any live order flow. Orders are submitted regardless of latency or rejection conditions.

---

## What Needs to Change

### File: `src/NT8.Adapters/Strategies/NT8StrategyBase.cs`

**Step 1:** Add `ExecutionCircuitBreaker` as a field on `NT8StrategyBase`.

```csharp
private ExecutionCircuitBreaker _circuitBreaker;
```

**Step 2:** Initialize it in `OnStateChange` → `State.DataLoaded`:
```csharp
// Use Microsoft.Extensions.Logging NullLogger for now (or wire to BasicLogger)
_circuitBreaker = new ExecutionCircuitBreaker(
    new NullLogger<ExecutionCircuitBreaker>(),
    failureThreshold: 3,
    timeout: TimeSpan.FromSeconds(30));
```

**Step 3:** Gate ALL order submissions through the circuit breaker.  
In the method that calls `ExecuteIntent()` (or wherever orders flow from strategy intent to the adapter), add:

```csharp
private bool TrySubmitIntent(StrategyIntent intent, StrategyContext context)
{
    if (!_circuitBreaker.ShouldAllowOrder())
    {
        var state = _circuitBreaker.GetState();
        Print(string.Format("[NT8-SDK] Circuit breaker OPEN — order blocked. Reason: {0}", state.Reason));
        return false;
    }

    try
    {
        _orderAdapter.ExecuteIntent(intent, context, _strategyConfig);
        _circuitBreaker.OnSuccess();
        return true;
    }
    catch (Exception ex)
    {
        _circuitBreaker.OnFailure();
        _circuitBreaker.RecordOrderRejection(ex.Message);
        Print(string.Format("[NT8-SDK] Order execution failed: {0}", ex.Message));
        return false;
    }
}
```

**Step 4:** Wire `OnOrderUpdate` rejections back to the circuit breaker.  
In `NT8StrategyBase.OnOrderUpdate()`:
```csharp
protected override void OnOrderUpdate(Order order, double limitPrice, double stopPrice,
    int quantity, int filled, double averageFillPrice,
    OrderState orderState, DateTime time, ErrorCode error, string nativeError)
{
    if (orderState == OrderState.Rejected)
    {
        if (_circuitBreaker != null)
        {
            _circuitBreaker.RecordOrderRejection(
                string.Format("NT8 rejected order: {0} {1}", error, nativeError));
        }
    }

    // Pass through to adapter for state tracking
    if (_orderAdapter != null)
    {
        _orderAdapter.OnOrderUpdate(
            order != null ? order.Name : "unknown",
            limitPrice, stopPrice, quantity, filled,
            averageFillPrice,
            orderState != null ? orderState.ToString() : "unknown",
            time, error.ToString(), nativeError ?? string.Empty);
    }
}
```

---

## Acceptance Criteria

- [ ] `ExecutionCircuitBreaker` is instantiated in `NT8StrategyBase`
- [ ] All order submissions go through `_circuitBreaker.ShouldAllowOrder()` — if false, order is blocked and logged
- [ ] NT8 order rejections call `_circuitBreaker.RecordOrderRejection()`
- [ ] 3 consecutive rejections open the circuit breaker (blocks further orders for 30 seconds)
- [ ] After 30 seconds, circuit breaker enters half-open and allows one test order
- [ ] `verify-build.bat` passes

---

## Files to Modify

| File | Action |
|---|---|
| `src/NT8.Adapters/Strategies/NT8StrategyBase.cs` | Add circuit breaker field, initialize, gate submissions, wire rejections |

## Files to NOT Change

- `src/NT8.Core/Execution/ExecutionCircuitBreaker.cs` — complete and correct, do not touch
- Any test files