public IEnumerable <ScanCompareResult> Compare(IEnumerable <IFile> targetSource)
{
List <ScanCompareResult> results = new List <ScanCompareResult>();
foreach (IFile target in targetSource)
{
ScanCompareResult result = GetTargetScanResult(target);
if (result != null)
{
results.Add(result);
}
}
var existing = results.Where(sr => sr.OldScan != null).Select(sr => sr.OldScan).ToList();
foreach (IFile current in _currentState)
{
if (!existing.Contains(current, comparer))
{
var result = new ScanCompareResult()
{
Result = CompareResult.Removed,
OldScan = current
};
results.Add(result);
}
}
return(results);
}
private ScanCompareResult GetTargetScanResult(IFile target)
{
ScanCompareResult result = null;
//- first most strict same
var locationMatch = _currentState.SingleOrDefault(f => f.FileLocation == target.FileLocation);
if (locationMatch != null)
{
result = new ScanCompareResult()
{
Result = CompareResult.NoChange,
NewScan = target,
OldScan = locationMatch
};
}
else
{
var fileMatch = _currentState.SingleOrDefault(f => f.FileName == target.FileName && f.Extension == target.Extension);
if (fileMatch != null)
{
result = new ScanCompareResult()
{
Result = CompareResult.Moved,
NewScan = target,
OldScan = fileMatch
};
}
else
{
result = new ScanCompareResult()
{
Result = CompareResult.New,
NewScan = target
};
}
}
return(result);
}