Re

re.swift

import Foundation
import ReactiveSwift

public protocol ActionProtocol {}

public protocol ViewStateProtocol {}

public typealias Reducer<ViewState: ViewStateProtocol> = SignalProducer<ViewState, Never>

open class ReducerFactory<Action: ActionProtocol, ViewState: ViewStateProtocol> {

    public init() {}

    open func reduce(
        _ action: Action,
        viewState: ViewState
    ) -> Reducer<ViewState> {
        return .empty
    }
}

open class Store<Action: ActionProtocol, ViewState: ViewStateProtocol> {

    public var viewState: ViewState {
        return mutableViewState.value
    }

    private let mutableViewState: MutableProperty<ViewState>

    private let reducerFactory: ReducerFactory<Action, ViewState>
    private let scheduler: QueueScheduler

    public init(
        initialViewState: ViewState,
        reducerFactory: ReducerFactory<Action, ViewState>
    ) {
        self.mutableViewState = MutableProperty(initialViewState)
        self.reducerFactory = reducerFactory
        self.scheduler = QueueScheduler(qos: .userInitiated)
    }

    public func subscribe(
        _ update: @escaping (ViewState) -> Void
    ) -> Disposable? {
        return mutableViewState.producer
            .observe(on: UIScheduler())
            .startWithValues { update($0) }
    }

    open func dispatch(_ action: Action) {
        mutableViewState <~ reducerFactory
            .reduce(action, viewState: mutableViewState.value)
            .start(on: scheduler)
    }
}