/// <summary>
/// Updates the local file copy state if the file has already been transferred (and local DB doesn't know about it).
/// </summary>
/// <param name="file"></param>
/// <param name="fs"></param>
private async Task UpdateFileCopyStateIfFileAlreadyExistsAtProvidersAsync(BackupFile file, SourceLocation source, FileStream fs)
{
// for each provider that needs this file:
// > double check that we haven't already transferred this whole file.
// > this avoids a full upload if for some reason we have lost our client database state.
bool stateChanged = false;
foreach (var provider in Providers)
{
var directory = await Database.GetDirectoryMapItemAsync(file.Directory).ConfigureAwait(false);
var providerState = await provider.Value.GetFileStatusAsync(file, source, directory).ConfigureAwait(false);
// compare the results from the remote provider to the local known state.
// if things are different, then apply the remote state to known local and save the changes.
if (file.UpdateLocalStateIfRemoteStateDoesNotMatch(providerState))
{
stateChanged = true;
}
}
if (stateChanged)
{
Logger.WriteTraceMessage("Found a sync mismatch. A provider state does not match local status, updating now.", InstanceID);
await Database.UpdateBackupFileCopyStateAsync(file).ConfigureAwait(false);
}
}