public async Task FindDuplicates()
{
FileMapBySize fileMapBySize = await FileMapBySize.GetNew(
dispatcher,
_rootDirectory,
OnFileReadError,
OnFileScanned);
await BuildDuplicatesList(fileMapBySize);
}
//we use a static GetNew instead of a public constructor
//as some things like waiting on async operations
//and setting event handlers cannot be done in the
//constructor. the real constructor is kept private
//and only ever called from this static GetNew method
public static async Task <FileMapBySize> GetNew(
IDispatcher d,
IDirectory dir,
DuplicateFileFinder.FileReadError error,
EventHandler onscanned)
{
var fileMapBySize = new FileMapBySize(d);
fileMapBySize.OnFileReadError = error;
fileMapBySize.OnFileScanned = onscanned;
await fileMapBySize.Populate(dir);
return(fileMapBySize);
}
private async Task BuildDuplicatesList(FileMapBySize fileMapBySize)
{
var fileMapByHashCode = new FileMapByString();
foreach (IFile file in fileMapBySize.GetPotentialDuplicates())
{
try
{
string hash = await file.GetUniqueHash(dispatcher, OnHashProgress);
List <IFile> list;
if (!fileMapByHashCode.TryGetValue(hash, out list))
{
list = new List <IFile>();
fileMapByHashCode.Add(hash, list);
}
list.Add(file);
// Once we have two files with the same hashcode
// we know that a duplicate has been found
if (list.Count > 1)
{
if (!_duplicates.ContainsKey(hash))
{
_duplicates.Add(hash, list);
}
NotifyDuplicateFound(list, hash, file);
}
}
catch (Exception e)
{
NotifyFileReadError(file, e);
}
}
}