Zip<TFirst, TSecond, TResult>
using System.Collections.Generic;
using System.Reactive.Disposables;
using System.Threading;
namespace System.Reactive.Linq.ObservableImpl
{
internal static class Zip<TFirst, TSecond, TResult>
{
internal sealed class Observable : Producer<TResult, Observable._>
{
internal sealed class _ : IdentitySink<TResult>
{
private sealed class FirstObserver : IObserver<TFirst>, IDisposable
{
private readonly _ _parent;
private SecondObserver _other;
private readonly Queue<TFirst> _queue;
public SecondObserver Other {
set {
_other = value;
}
}
public Queue<TFirst> Queue => _queue;
public bool Done { get; set; }
public FirstObserver(_ parent)
{
_parent = parent;
_queue = new Queue<TFirst>();
}
public void OnNext(TFirst value)
{
lock (_parent._gate) {
if (_other.Queue.Count > 0) {
TSecond arg = _other.Queue.Dequeue();
TResult val = default(TResult);
try {
val = _parent._resultSelector(value, arg);
} catch (Exception error) {
_parent.ForwardOnError(error);
return;
}
_parent.ForwardOnNext(val);
} else if (_other.Done) {
_parent.ForwardOnCompleted();
} else {
_queue.Enqueue(value);
}
}
}
public void OnError(Exception error)
{
lock (_parent._gate) {
_parent.ForwardOnError(error);
}
}
public void OnCompleted()
{
lock (_parent._gate) {
Done = true;
if (_other.Done)
_parent.ForwardOnCompleted();
else
Disposable.TryDispose(ref _parent._firstDisposable);
}
}
public void Dispose()
{
_queue.Clear();
}
}
private sealed class SecondObserver : IObserver<TSecond>, IDisposable
{
private readonly _ _parent;
private FirstObserver _other;
private readonly Queue<TSecond> _queue;
public FirstObserver Other {
set {
_other = value;
}
}
public Queue<TSecond> Queue => _queue;
public bool Done { get; set; }
public SecondObserver(_ parent)
{
_parent = parent;
_queue = new Queue<TSecond>();
}
public void OnNext(TSecond value)
{
lock (_parent._gate) {
if (_other.Queue.Count > 0) {
TFirst arg = _other.Queue.Dequeue();
TResult val = default(TResult);
try {
val = _parent._resultSelector(arg, value);
} catch (Exception error) {
_parent.ForwardOnError(error);
return;
}
_parent.ForwardOnNext(val);
} else if (_other.Done) {
_parent.ForwardOnCompleted();
} else {
_queue.Enqueue(value);
}
}
}
public void OnError(Exception error)
{
lock (_parent._gate) {
_parent.ForwardOnError(error);
}
}
public void OnCompleted()
{
lock (_parent._gate) {
Done = true;
if (_other.Done)
_parent.ForwardOnCompleted();
else
Disposable.TryDispose(ref _parent._secondDisposable);
}
}
public void Dispose()
{
_queue.Clear();
}
}
private readonly Func<TFirst, TSecond, TResult> _resultSelector;
private readonly object _gate;
private readonly FirstObserver _firstObserver;
private IDisposable _firstDisposable;
private readonly SecondObserver _secondObserver;
private IDisposable _secondDisposable;
public _(Func<TFirst, TSecond, TResult> resultSelector, IObserver<TResult> observer)
: base(observer)
{
_gate = new object();
_firstObserver = new FirstObserver(this);
_secondObserver = new SecondObserver(this);
_firstObserver.Other = _secondObserver;
_secondObserver.Other = _firstObserver;
_resultSelector = resultSelector;
}
public void Run(IObservable<TFirst> first, IObservable<TSecond> second)
{
Disposable.SetSingle(ref _firstDisposable, ObservableExtensions.SubscribeSafe<TFirst>(first, (IObserver<TFirst>)_firstObserver));
Disposable.SetSingle(ref _secondDisposable, ObservableExtensions.SubscribeSafe<TSecond>(second, (IObserver<TSecond>)_secondObserver));
}
protected override void Dispose(bool disposing)
{
if (disposing) {
Disposable.TryDispose(ref _firstDisposable);
Disposable.TryDispose(ref _secondDisposable);
lock (_gate) {
_firstObserver.Dispose();
_secondObserver.Dispose();
}
}
base.Dispose(disposing);
}
}
private readonly IObservable<TFirst> _first;
private readonly IObservable<TSecond> _second;
private readonly Func<TFirst, TSecond, TResult> _resultSelector;
public Observable(IObservable<TFirst> first, IObservable<TSecond> second, Func<TFirst, TSecond, TResult> resultSelector)
{
_first = first;
_second = second;
_resultSelector = resultSelector;
}
protected override _ CreateSink(IObserver<TResult> observer)
{
return new _(_resultSelector, observer);
}
protected override void Run(_ sink)
{
sink.Run(_first, _second);
}
}
internal sealed class Enumerable : Producer<TResult, Enumerable._>
{
internal sealed class _ : Sink<TFirst, TResult>
{
private readonly Func<TFirst, TSecond, TResult> _resultSelector;
private IEnumerator<TSecond> _rightEnumerator;
private static readonly IEnumerator<TSecond> DisposedEnumerator = MakeDisposedEnumerator();
public _(Func<TFirst, TSecond, TResult> resultSelector, IObserver<TResult> observer)
: base(observer)
{
_resultSelector = resultSelector;
}
private static IEnumerator<TSecond> MakeDisposedEnumerator()
{
yield break;
}
public void Run(IObservable<TFirst> first, IEnumerable<TSecond> second)
{
try {
IEnumerator<TSecond> enumerator = second.GetEnumerator();
if (Interlocked.CompareExchange<IEnumerator<TSecond>>(ref _rightEnumerator, enumerator, (IEnumerator<TSecond>)null) != null) {
enumerator.Dispose();
return;
}
} catch (Exception error) {
ForwardOnError(error);
return;
}
Run(first);
}
protected override void Dispose(bool disposing)
{
if (disposing)
Interlocked.Exchange<IEnumerator<TSecond>>(ref _rightEnumerator, DisposedEnumerator)?.Dispose();
base.Dispose(disposing);
}
public override void OnNext(TFirst value)
{
bool flag = false;
try {
flag = _rightEnumerator.MoveNext();
} catch (Exception error) {
ForwardOnError(error);
return;
}
if (flag) {
TSecond val = default(TSecond);
try {
val = _rightEnumerator.Current;
} catch (Exception error2) {
ForwardOnError(error2);
return;
}
TResult value2;
try {
value2 = _resultSelector(value, val);
} catch (Exception error3) {
ForwardOnError(error3);
return;
}
ForwardOnNext(value2);
} else
ForwardOnCompleted();
}
}
private readonly IObservable<TFirst> _first;
private readonly IEnumerable<TSecond> _second;
private readonly Func<TFirst, TSecond, TResult> _resultSelector;
public Enumerable(IObservable<TFirst> first, IEnumerable<TSecond> second, Func<TFirst, TSecond, TResult> resultSelector)
{
_first = first;
_second = second;
_resultSelector = resultSelector;
}
protected override _ CreateSink(IObserver<TResult> observer)
{
return new _(_resultSelector, observer);
}
protected override void Run(_ sink)
{
sink.Run(_first, _second);
}
}
}
}