public IDisposable Subscribe(IObserver <ListChange <T> > observer)
{
lock (_gate)
{
if (_value.Count > 0)
{
var changes = ListChange.Combine(_value.Select((item, index) => ListChange.Insert(index, item)));
observer.OnNext(changes);
}
switch (_state)
{
case State.Unconnected:
case State.Connected:
_observers = _observers.Add(observer);
return(Disposable.Create(() =>
{
lock (_gate)
_observers = _observers.Remove(observer);
}));
case State.Completed:
observer.OnCompleted();
return(Disposable.Empty);
case State.Error:
observer.OnError(_error);
return(Disposable.Empty);
default:
throw new Exception("ReplayObservableList.Subscribe: Impossible");
}
}
}
IObserver <ListChange <T> > LeftObserver()
{
return(Observer.Create <ListChange <T> >(
onNext: changes =>
{
lock (_gate)
{
var newChanges = new List <ListChange <T> >();
changes(
insert: (index, item) =>
{
newChanges.Add(ListChange.Insert(index, item));
++_leftCount;
},
replace: (index, item) => { newChanges.Add(ListChange.Replace(index, item)); },
remove: index =>
{
newChanges.Add(ListChange.Remove <T>(index));
--_leftCount;
},
clear: () =>
{
if (_rightCount == 0)
{
newChanges.Add(ListChange.Clear <T>());
}
else
{
for (var i = _leftCount - 1; i >= 0; --i)
{
newChanges.Add(ListChange.Remove <T>(i));
}
}
_leftCount = 0;
});
if (newChanges.Count > 0)
{
_observer.OnNext(ListChange.Combine(newChanges));
}
}
},
onCompleted: () =>
{
lock (_gate)
{
if (_rightCompleted)
{
_observer.OnCompleted();
}
_leftCompleted = true;
}
},
onError: e =>
{
lock (_gate)
_observer.OnError(e);
}));
}
public ListBehaviorSubject(IEnumerable <T> value)
: this()
{
var change = ListChange.Combine(value.Select((item, index) => ListChange.Insert(index, item)).ToArray());
OnNext(change);
}
public IDisposable Subscribe(IObserver <ListChange <T> > observer)
{
var mapper = new WhereChangeMapper();
var gate = new object();
return(_source.Subscribe(
Observer.Create <ListChange <T> >(
onNext: change =>
{
lock (gate)
{
var newChanges = new List <ListChange <T> >();
change(
insert: (index, item) => newChanges.AddRange(mapper.Insert(index, item, _predicate(item))),
replace: (index, item) => newChanges.AddRange(mapper.Replace(index, item, _predicate(item))),
remove: index => newChanges.AddRange(mapper.Remove <T>(index)),
clear: () => newChanges.AddRange(mapper.Clear <T>()));
if (newChanges.Count > 0)
{
observer.OnNext(ListChange.Combine(newChanges));
}
}
},
onCompleted: observer.OnCompleted,
onError: observer.OnError)));
}
public void OnNext(ListChange <T> change)
{
lock (_mutex)
{
_value = change.Apply(_value);
_subject.OnNext(change);
}
}
public static void ApplyLegacy <T>(this ListChange <T> changes, IList list)
{
changes(
insert: (i, x) => list.Insert(i, x),
replace: (i, x) => list[i] = x,
remove: list.RemoveAt,
clear: list.Clear);
}
public static ListChange <TResult> Select <TSource, TResult>(this ListChange <TSource> self, Func <TSource, TResult> select)
{
return((insert, replace, remove, clear) =>
self(
insert: (i, x) => insert(i, select(x)),
replace: (i, x) => replace(i, select(x)),
remove: remove,
clear: clear));
}
public IDisposable Subscribe(IObserver <ListChange <T> > observer)
{
if (_changes == null)
{
_changes = ListChange.Combine(_value.Select((t, i) => ListChange.Insert(i, t)));
}
observer.OnNext(_changes);
observer.OnCompleted();
return(Disposable.Empty);
}
public Optional <ListChange <T> > Clear <T>()
{
var oldTrueCount = _items.Sum();
_items = _items.Clear();
return(oldTrueCount == 0
? Optional.None <ListChange <T> >()
: ListChange.Clear <T>());
}
public Optional <ListChange <T> > Insert <T>(int index, T item, bool predicateTrue)
{
var toIndex = _items.Sum(index);
_items = _items.Insert(index, predicateTrue ? 1 : 0);
return(predicateTrue
? ListChange.Insert(toIndex, item)
: Optional.None <ListChange <T> >());
}
public IDisposable Subscribe(IObserver <ListChange <T> > observer)
{
lock (_mutex)
{
var change = ListChange.Combine(_value.Select((item, index) => ListChange.Insert(index, item)).ToArray());
observer.OnNext(change);
return(_subject.Subscribe(observer));
}
}
public Optional <ListChange <T> > Remove <T>(int index)
{
var toIndex = _items.Sum(index);
var predicateTrue = _items[index] == 1;
_items = _items.RemoveAt(index);
return(predicateTrue
? ListChange.Remove <T>(toIndex)
: Optional.None <ListChange <T> >());
}
public static SumTree <T> Apply <T>(this ListChange <T> changes, SumTree <T> tree)
{
var result = tree;
changes(
insert: (i, x) => result = result.Insert(i, x),
replace: (i, x) => result = result.ReplaceAt(i, x),
remove: i => result = result.RemoveAt(i),
clear: () => result = result.Clear());
return(result);
}
public static ImmutableList <T> Apply <T>(this ListChange <T> changes, ImmutableList <T> list)
{
var result = list;
changes(
insert: (i, x) => result = result.Insert(i, x),
replace: (i, x) => result = result.SetItem(i, x),
remove: i => result = result.RemoveAt(i),
clear: () => result = ImmutableList <T> .Empty);
return(result);
}
public void OnNext(ListChange <IObservable <T> > changes)
{
lock (_gate)
{
changes(
insert: (index, obs) =>
{
var indexedItem = new IndexTrackerList <SingleAssignmentDisposable> .IndexedItem(new SingleAssignmentDisposable());
_innerSubscriptions.Insert(index, indexedItem);
_changeMapper.InsertFalse(index);
_innerCompleted = _innerCompleted.Insert(index, false);
indexedItem.Value.Disposable = SubscribeInner(obs, indexedItem);
},
replace: (index, obs) =>
{
_innerSubscriptions[index].Dispose();
var indexedItem = new IndexTrackerList <SingleAssignmentDisposable> .IndexedItem(new SingleAssignmentDisposable());
_innerSubscriptions.Replace(index, indexedItem);
_innerCompleted = _innerCompleted.ReplaceAt(index, false);
indexedItem.Value.Disposable = SubscribeInner(obs, indexedItem);
// The new observable hasn't produced any values left, so remove any leftover old values
foreach (var change in _changeMapper.ReplaceFalse <T>(index))
{
_observer.OnNext(change);
}
},
remove: (index) =>
{
_innerSubscriptions[index].Dispose();
_innerSubscriptions.Remove(index);
_innerCompleted = _innerCompleted.RemoveAt(index);
foreach (var change in _changeMapper.Remove <T>(index))
{
_observer.OnNext(change);
}
},
clear: () =>
{
Disposable.Combine(_innerSubscriptions).Dispose();
_innerSubscriptions.Clear();
_innerCompleted = SumTree <bool> .Empty(false, (d1, d2) => d1 && d2);
foreach (var change in _changeMapper.Clear <T>())
{
_observer.OnNext(change);
}
});
}
}
public static IObservableList <T> ToObservableList <T>(this IObservable <IImmutableList <T> > self)
{
return(self
.Scan(
new
{
PrevList = (IImmutableList <T>)ImmutableList <T> .Empty,
Changes = Optional.None <ListChange <T> >()
},
(acc, newList) => new
{
PrevList = newList,
Changes = ListChange.IncrementalChanges(acc.PrevList, newList),
})
.SelectMany(acc => acc.Changes)
.UnsafeAsObservableList());
}
public static string ToString <T>(this ListChange <T> self)
{
var results = new List <string>();
self(
insert: (index, item) => results.Add("ListChange.Insert(" + index + ", " + item + ")"),
replace: (index, item) => results.Add("ListChange.Replace(" + index + ", " + item + ")"),
remove: index => results.Add("ListChange.Remove(" + index + ")"),
clear: () => results.Add("ListChange.Clear()"));
if (results.Count == 0)
{
return("ListChange.None()");
}
if (results.Count == 1)
{
return(results[0]);
}
return("ListChange.Combine(" + results.Join(", ") + ")");
}
public Optional <ListChange <T> > Replace <T>(int index, T item, bool predicateTrue)
{
var toIndex = _items.Sum(index);
var oldPredicateTrue = _items[index] == 1;
_items = _items.ReplaceAt(index, predicateTrue ? 1 : 0);
if (predicateTrue)
{
return(oldPredicateTrue
? ListChange.Replace(toIndex, item)
: ListChange.Insert(toIndex, item));
}
else
{
return(oldPredicateTrue
? ListChange.Remove <T>(toIndex)
: Optional.None <ListChange <T> >());
}
}
public T this[int i]
{
get { return(_value[i]); }
set { OnNext(ListChange.Replace(i, value)); }
}
public void OnInsert(int index, T item)
{
OnNext(ListChange.Insert(index, item));
}
public static IObservableList <T> SeparateBy <T>(this IObservableList <T> self, Func <T> separator)
{
return(self
.SelectWithState(
0,
(changes, res) =>
{
var newChanges = new List <ListChange <T> >();
var count = res;
changes(
insert: (i, item) =>
{
if (i == count) // inserting at the end
{
if (count == 0) // inserting first element: skip the separator
{
newChanges.Add(ListChange.Insert(0, item));
}
else // add separator before item
{
newChanges.Add(ListChange.Insert(i * 2 - 1, separator()));
newChanges.Add(ListChange.Insert(i * 2, item));
}
}
else // add separator after item
{
newChanges.Add(ListChange.Insert(i * 2, item));
newChanges.Add(ListChange.Insert(i * 2 + 1, separator()));
}
++count;
},
replace: (i, item) =>
{
newChanges.Add(ListChange.Replace(i * 2, item));
},
remove: i =>
{
if (i == count - 1) // removing at the end
{
if (i == 0) // removing first element: no separator to remove
{
newChanges.Add(ListChange.Remove <T>(0));
}
else // remove separator before item
{
newChanges.Add(ListChange.Remove <T>(i * 2));
newChanges.Add(ListChange.Remove <T>(i * 2 - 1));
}
}
else // remove separator after item
{
newChanges.Add(ListChange.Remove <T>(i * 2 + 1));
newChanges.Add(ListChange.Remove <T>(i * 2));
}
--count;
},
clear: () =>
{
newChanges.Add(ListChange.Clear <T>());
count = 0;
});
return SelectResult.Create(ListChange.Combine(newChanges), count);
})
.UnsafeAsObservableList());
}
public void OnRemove(int index)
{
OnNext(ListChange.Remove <T>(index));
}
public void OnReplace(int index, T item)
{
OnNext(ListChange.Replace(index, item));
}
public void OnClear()
{
OnNext(ListChange.Clear <T>());
}
public void OnAdd(T item)
{
lock (_mutex)
OnNext(ListChange.Insert(_value.Count, item));
}
public static IObservableList <T> Switch <T>(this IObservable <IObservableList <T> > self)
{
return(self.Select(ol => ol.StartWith(ListChange.Clear <T>())).Switch().UnsafeAsObservableList());
}
