RxSwift 데이터 처리

RxSwift 데이터 처리 

private func bind() {
        let blogResult = searchBar.shouldLoadResult
            .flatMapLatest { query in
                SearchBlogNetwork().searchBlog(query: query)
            }
            .share()
        
        let blogValue = blogResult
            .compactMap { data -> DKBlog? in
                guard case .success(let value) = data else { return nil }
                return value
            }
        
        let blogError = blogResult
            .compactMap { data -> String? in
                guard case .failure(let error) = data else { return nil }
                return error.localizedDescription
            }
        
        // 네트워크를 통해 가져온 값을 cellData로 변환
        let cellData = blogValue
            .map { blog -> [BlogListCellData] in
                return blog.documents
                    .map { doc in
                        let thumbnailURL = URL(string: doc.thumbnail ?? "")
                        return BlogListCellData(
                            thumbnailURL: thumbnailURL,
                            name: doc.name,
                            title: doc.title,
                            datetime: doc.datetime
                        )
                    }
            }
        
        // FilterView를 선택했을 때 나오는 alertsheet를 선택했을 때 type
        let sortedType = alertActionTapped
            .filter {
                switch $0 {
                case .title, .datetime:
                    return true
                default:
                    return false
                }
            }
            .startWith(.title)
        
        // MainViewController -> ListView
        Observable.combineLatest(
            sortedType,
            cellData
        ) { type, data -> [BlogListCellData] in
            switch type {
            case .title:
                return data.sorted { $0.title ?? "" < $1.title ?? "" }
            case .datetime:
                return data.sorted { $0.datetime ?? Date() > $1.datetime ?? Date() }
            default:
                return data
            }
        }
        .bind(to: listView.cellData)
        .disposed(by: disposeBag)
        
        let alertSheetForSorting = listView.headerView.sortButtonTapped
            .map { _ -> Alert in
                return (title: nil, message: nil, actions: [.title, .datetime, .cancel], style: .actionSheet)
            }
        
        let alertForErrorMessage = blogError
            .map { message -> Alert in
                return (
                    title: "앗!",
                    message: "예상치 못한 오류가 발생했습니다. 잠시 후 다시 시도해주세요. \(message)",
                    actions: [.confirm],
                    style: .alert
                )
            }
        Observable
            .merge(
                alertSheetForSorting,
                alertForErrorMessage
            )
            .asSignal(onErrorSignalWith: .empty())
            .flatMapLatest { alert -> Signal<AlertAction> in
                let alertController = UIAlertController(title: alert.title, message: alert.message, preferredStyle: alert.style)
                return self.presentAlertController(alertController, actions: alert.actions)
            }
            .emit(to: alertActionTapped)
            .disposed(by: disposeBag)
    }