public static IEnumerable <TResult> SelectMany <TSource, TResult>(this IZippable <TSource> source,
Func <TSource, IZippable <TResult> > selector)
{
if (source == null)
{
throw new ArgumentNullException("source");
}
if (selector == null)
{
throw new ArgumentNullException("selector");
}
return(SelectManyImpl(source, (value, index) => selector(value),
(originalElement, subsequenceElement) => subsequenceElement));
}
public static void Unzip(IEnumerable <string> paths, IEnumerable <string> selectors, string location)
{
foreach (string path in paths)
{
ZipDirectory rootDir = Index(path);
if (rootDir == null)
{
continue;
}
using (MemoryMappedFile mmf =
MemoryMappedFile.CreateFromFile(path, FileMode.Open))
{
foreach (string selector in selectors)
{
ConsoleUtil.PrintInfo($"Searching for selector: {selector}");
IZippable zip = SelectorSearch(
rootDir,
selector.Split(
new char[] { '\\', '/' },
StringSplitOptions.RemoveEmptyEntries));
try
{
if (zip is ZipDirectory zdir)
{
ConsoleUtil.PrintMessage(
$"Unpacking directory {zdir.Name} from {path}");
UnpackDirectory(zdir, mmf, location);
}
else if (zip is ZipFile zfile)
{
ConsoleUtil.PrintMessage(
$"Unpacking file {zfile.Name} from {path}");
UnpackFile(zfile, mmf, location);
}
else
{
ConsoleUtil.PrintWarning(
$"Selector {selector} not found in {path}");
}
}
catch (CorruptionException)
{
ConsoleUtil.PrintError(
"Unable to unzip because the .czip file is corrupt");
}
}
}
}
}
private static IZippable SelectorSearch(ZipDirectory root, IEnumerable <string> selector)
{
if (selector.Count() == 0)
{
return(root);
}
ConsoleUtil.PrintInfo($"Searching for {selector.First()} in {root.Name}");
IZippable zip = root.FindByName(selector.First());
if (selector.Count() == 1)
{
return(zip);
}
if (zip is ZipDirectory zdir)
{
return(SelectorSearch(zdir, selector.Skip(1)));
}
return(null);
}
/// <summary>
/// Actual code for SelectMany implementation. Instead of doing Cartesian Product, it
/// performs zipping.
/// </summary>
/// <typeparam name="TSource"></typeparam>
/// <typeparam name="TCollection"></typeparam>
/// <typeparam name="TResult"></typeparam>
/// <param name="source"></param>
/// <param name="collectionSelector"></param>
/// <param name="resultSelector"></param>
/// <returns></returns>
private static IEnumerable <TResult> SelectManyImpl <TSource, TCollection, TResult>(IZippable <TSource> source,
Func <TSource, int, IZippable <TCollection> > collectionSelector,
Func <TSource, TCollection, TResult> resultSelector)
{
int index = 0;
using (var e1 = source.GetEnumerator())
{
// a default(TSource) causes that using nested "from" in LINQ won't work. Example of what's not allowed:
// from entity in entities
// from element in entity.collection <- this won't work
// ....
using (var e2 = collectionSelector(default(TSource), index++).GetEnumerator())
{
while (true)
{
var isNext1 = e1.MoveNext();
var isNext2 = e2.MoveNext();
if (isNext1 && isNext2)
{
yield return(resultSelector(e1.Current, e2.Current));
}
else
{
yield break;
}
}
}
}
}
public static IEnumerable <TResult> SelectMany <TSource, TCollection, TResult>(this IZippable <TSource> source,
Func <TSource, IZippable <TCollection> > selector, Func <TSource, TCollection, TResult> select)
{
return(SelectManyImpl(source, (value, index) => selector(value), select));
}
