SKProductsRequest+Rx.swift

//
//  SKProductsRequest+Rx.swift
//
//  Created by Daniel Tartaglia on 8/28/19.
//  Copyright © 2019 Daniel Tartaglia. MIT License.
//

import RxSwift
import RxCocoa
import StoreKit

extension Reactive where Base: SKProductsRequest {

    var delegate: DelegateProxy<SKProductsRequest, SKProductsRequestDelegate> {
        return SKProductsRequestDelegateProxy.proxy(for: base)
    }

    var didReceive: Observable<SKProductsResponse> {
        return SKProductsRequestDelegateProxy.proxy(for: base).didReceiveResponse.asObservable()
    }

    var didFinish: Observable<Void> {
        return delegate.methodInvoked(#selector(SKProductsRequestDelegate.requestDidFinish(_:)))
            .map { _ in }
    }

    var didFail: Observable<Error> {
        return delegate.methodInvoked(#selector(SKProductsRequestDelegate.request(_:didFailWithError:)))
            .map { $0[1] as! Error }
    }
}

final class SKProductsRequestDelegateProxy
    : DelegateProxy<SKProductsRequest, SKProductsRequestDelegate>
    , DelegateProxyType
    , SKProductsRequestDelegate {

    init(request: SKProductsRequest) {
        super.init(parentObject: request, delegateProxy: SKProductsRequestDelegateProxy.self)
    }

    static func registerKnownImplementations() {
        self.register { SKProductsRequestDelegateProxy(request: $0) }
    }

    func productsRequest(_ request: SKProductsRequest, didReceive response: SKProductsResponse) {
        didReceiveResponse.onNext(response)
    }

    deinit {
        didReceiveResponse.onCompleted()
    }

    fileprivate let didReceiveResponse = PublishSubject<SKProductsResponse>()
}

extension SKProductsRequest: HasDelegate { }