createlightingfeature.swift

func createLightingFeature(store      : Store,
                           lightsStack: LightsStack,
                           output     : @escaping Output) -> Input
{
    let loader      = LightsLoader    (lightsStack:lightsStack,store:store,responder:handle(output:output))
    let switcher    = LightSwitcher   (lightsStack:lightsStack,store:store,responder:handle(output:output))
    let valueSetter = LightValueSetter(lightsStack:lightsStack,store:store,responder:handle(output:output))
    let dimmer      = Dimmer          (lightsStack:lightsStack,store:store,responder:handle(output:output))
    let changer     = LightChanger    (lightsStack:lightsStack,store:store,responder:handle(output:output))
    
    func execute(command cmd: Message._Lighting) {
        //          |---------- Global Command ---------|         request |- UseCase -| to |<-------- UseCase Request -------->|
        if case let .load(lightsOrRooms)                  = cmd { request( loader,      to:.load(.all(lightsOrRooms))            ) }
        if case let .turn(light, onOrOff)                 = cmd { request( switcher,    to:.turn(light, onOrOff )                ) }
        if case let .apply(config,              on:light) = cmd { request( valueSetter, to:.apply(config,              on:light) ) }
        if case let .increase(value,by:increase,on:light) = cmd { request( dimmer,      to:.increase(value,by:increase,on:light) ) }
        if case let .decrease(value,by:decrease,on:light) = cmd { request( dimmer,      to:.decrease(value,by:decrease,on:light) ) }
        if case let .change(.name(name),        on:light) = cmd { request( changer,     to:.change(.name(name),        on:light) ) }
        if case let .change(.display(interface),on:light) = cmd { request( changer,     to:.change(.display(interface),on:light) ) }
    }
    return { // entry point
        if case .lighting(let c) = $0 { execute(command:c) } // execute if lighting is command's recipient
    }
}
// MARK: - UseCase response handler
private func handle(output: @escaping Output) -> (   LightSwitcher.Response) -> () { { process(response:$0,output:output) } }
private func handle(output: @escaping Output) -> (LightValueSetter.Response) -> () { { process(response:$0,output:output) } }
private func handle(output: @escaping Output) -> (          Dimmer.Response) -> () { { process(response:$0,output:output) } }
private func handle(output: @escaping Output) -> (    LightChanger.Response) -> () { { process(response:$0,output:output) } }
private func handle(output: @escaping Output) -> (    LightsLoader.Response) -> () { { process(response:$0,output:output) } }

private func process(response:   LightSwitcher.Response, output: @escaping Output) { switch response { case let .light   (light,.was(turned:onOrOff)      ): output( .lighting(.turning (light, onOrOff,.succeeded       )) ) }}
private func process(response:LightValueSetter.Response, output: @escaping Output) { switch response { case let .applying(values,on:light,succeededOrFaild): output( .lighting(.applying(values,on:light,succeededOrFaild)) ) }}
private func process(response:    LightsLoader.Response, output: @escaping Output) { switch response { case let .loading (lightsOrRooms,  succeededOrFaild): output( .lighting(.loading (lightsOrRooms,  succeededOrFaild)) ) }}
private func process(response:          Dimmer.Response, output: @escaping Output) {
    switch response {
    case let .increase(value,by:increment,on:light,succeededOrFaild): output( .lighting(.increasing(value,by:increment,on:light,succeededOrFaild)) )
    case let .decrease(value,by:increment,on:light,succeededOrFaild): output( .lighting(.decreasing(value,by:increment,on:light,succeededOrFaild)) )
    }
}
private func process(response:    LightChanger.Response, output: @escaping Output) {
    switch response {
    case let .changing(.title(name),       on:light,succeededOrFaild): output( .lighting(.changing(.name(name),        on:light,succeededOrFaild)) )
    case let .changing(.display(interface),on:light, _              ): output( .lighting(.changing(.display(interface),on:light,.succeeded      )) )
    }
}