# MEXC API Fee Synchronization Implementation

## Overview

This implementation adds automatic synchronization of trading fees between the MEXC API and your local configuration files. The system will:

1. **Fetch current trading fees** from MEXC API on startup
2. **Automatically update** your `config.yaml` with the latest fees
3. **Periodically sync** fees to keep them current
4. **Maintain backup** of configuration files
5. **Track sync history** for auditing

## Features

### ✅ Automatic Fee Retrieval
- Fetches maker/taker commission rates from MEXC account API
- Converts basis points to decimal percentages
- Handles API errors gracefully with fallback values

### ✅ Smart Configuration Updates
- Only updates config when fees actually change
- Creates timestamped backups before modifications
- Preserves all other configuration settings
- Adds metadata tracking when fees were last synced

### ✅ Integration with Trading System
- Automatically syncs on TradingExecutor startup
- Reloads configuration after fee updates
- Provides manual sync methods for testing
- Includes sync status in trading statistics

### ✅ Robust Error Handling
- Graceful fallback to hardcoded values if API fails
- Comprehensive logging of all sync operations
- Detailed error reporting and recovery

## Implementation Details

### New Files Added

1. **`core/config_sync.py`** - Main synchronization logic
2. **`test_fee_sync.py`** - Test script for validation
3. **`MEXC_FEE_SYNC_IMPLEMENTATION.md`** - This documentation

### Enhanced Files

1. **`NN/exchanges/mexc_interface.py`** - Added fee retrieval methods
2. **`core/trading_executor.py`** - Integrated sync functionality

## Usage

### Automatic Synchronization (Default)

When you start your trading system, fees will be automatically synced:

```python
# This now includes automatic fee sync on startup
executor = TradingExecutor("config.yaml")
```

### Manual Synchronization

```python
# Force immediate sync
sync_result = executor.sync_fees_with_api(force=True)

# Check sync status
status = executor.get_fee_sync_status()

# Auto-sync if needed
executor.auto_sync_fees_if_needed()
```

### Direct API Testing

```bash
# Test the fee sync functionality
python test_fee_sync.py
```

## Configuration Changes

### New Config Sections Added

```yaml
trading:
  trading_fees:
    maker: 0.0000          # Auto-updated from MEXC API
    taker: 0.0005          # Auto-updated from MEXC API  
    default: 0.0005        # Auto-updated from MEXC API
  
  # New metadata section (auto-generated)
  fee_sync_metadata:
    last_sync: "2024-01-15T10:30:00"
    api_source: "mexc"
    sync_enabled: true
    api_commission_rates:
      maker: 0              # Raw basis points from API
      taker: 50             # Raw basis points from API
```

### Backup Files

The system creates timestamped backups:
- `config.yaml.backup_20240115_103000`
- Keeps configuration history for safety

### Sync History

Detailed sync history is maintained in:
- `logs/config_sync_history.json`
- Contains last 100 sync operations
- Useful for debugging and auditing

## API Methods Added

### MEXCInterface New Methods

```python
# Get account-level trading fees
fees = mexc.get_trading_fees()
# Returns: {'maker_rate': 0.0000, 'taker_rate': 0.0005, 'source': 'mexc_api'}

# Get symbol-specific fees (future enhancement)
fees = mexc.get_symbol_trading_fees("ETH/USDT")
```

### ConfigSynchronizer Methods

```python
# Manual fee sync
sync_result = config_sync.sync_trading_fees(force=True)

# Auto sync (respects timing intervals)
success = config_sync.auto_sync_fees()

# Get sync status and history
status = config_sync.get_sync_status()

# Enable/disable auto-sync
config_sync.enable_auto_sync(True)
```

### TradingExecutor New Methods

```python
# Sync fees through trading executor
result = executor.sync_fees_with_api(force=True)

# Check if auto-sync is needed
executor.auto_sync_fees_if_needed()

# Get comprehensive sync status
status = executor.get_fee_sync_status()
```

## Error Handling

### API Connection Failures
- Falls back to existing config values
- Logs warnings but doesn't stop trading
- Retries on next sync interval

### Configuration File Issues
- Creates backups before any changes
- Validates config structure before saving
- Recovers from backup if save fails

### Fee Validation
- Checks for reasonable fee ranges (0-1%)
- Logs warnings for unusual fee changes
- Requires significant change (>0.000001) to update

## Sync Timing

### Default Intervals
- **Startup sync**: Immediate on TradingExecutor initialization
- **Auto-sync interval**: Every 3600 seconds (1 hour)
- **Manual sync**: Available anytime

### Configurable Settings
```python
config_sync.sync_interval = 1800  # 30 minutes
config_sync.backup_enabled = True
```

## Benefits

### 1. **Always Current Fees**
- No more outdated hardcoded fees
- Automatic updates when MEXC changes rates
- Accurate P&L calculations

### 2. **Zero Maintenance**
- Set up once, works automatically
- No manual config file editing needed
- Handles fee tier changes automatically

### 3. **Audit Trail**
- Complete history of all fee changes
- Timestamped sync records
- Easy troubleshooting and compliance

### 4. **Safety First**
- Configuration backups before changes
- Graceful error handling
- Can disable auto-sync if needed

## Testing

### Run Complete Test Suite
```bash
python test_fee_sync.py
```

### Test Output Example
```
=== Testing MEXC Fee Retrieval ===
MEXC: Connection successful
MEXC: Fetching trading fees...
MEXC Trading Fees Retrieved:
  Maker Rate: 0.000%
  Taker Rate: 0.050%
  Source: mexc_api

=== Testing Config Synchronization ===
CONFIG SYNC: Fetching trading fees from MEXC API
CONFIG SYNC: Updated taker fee: 0.0005 -> 0.0005
CONFIG SYNC: Successfully synced trading fees

=== Testing TradingExecutor Integration ===
TRADING EXECUTOR: Performing initial fee synchronization with MEXC API
TRADING EXECUTOR: Fee synchronization completed successfully

TEST SUMMARY:
  MEXC API Fee Retrieval: PASS
  Config Synchronization: PASS  
  TradingExecutor Integration: PASS

ALL TESTS PASSED! Fee synchronization is working correctly.
```

## Next Steps

### Immediate Use
1. Run `python test_fee_sync.py` to verify setup
2. Start your trading system normally
3. Check logs for successful fee sync messages

### Optional Enhancements
1. Add symbol-specific fee rates
2. Implement webhook notifications for fee changes
3. Add GUI controls for sync management
4. Export sync history to CSV/Excel

## Security Notes

- Uses existing MEXC API credentials from `.env`
- Only reads account info (no trading permissions needed for fees)
- Configuration backups protect against data loss
- All sync operations are logged for audit

## Troubleshooting

### Common Issues

1. **"No MEXC interface available"**
   - Check API credentials in `.env` file
   - Verify trading is enabled in config

2. **"API returned fallback values"**
   - MEXC API may be temporarily unavailable
   - System continues with existing fees

3. **"Failed to save updated config"**
   - Check file permissions on `config.yaml`
   - Ensure disk space is available

### Debug Logging
```python
import logging
logging.getLogger('core.config_sync').setLevel(logging.DEBUG)
```

This implementation provides a robust, automatic solution for keeping your trading fees synchronized with MEXC's current rates, ensuring accurate trading calculations and eliminating manual configuration maintenance.