LONDON-IOS/GME Remit/Modules/ManageAgreement/User Interface/Presenter/ManageAgreementPresenter.swift

//
//  ManageAgreementPresenter.swift
//  GME Remit
//
//  Created by InKwon James Kim on 2019/12/23.
//Copyright © 2019 Gobal Money Express Co. Ltd. All rights reserved.
//

import RxSwift
import RxCocoa

class ManageAgreementPresenter: ViewModelType {
  var interactor: ManageAgreementInteractorInput?
  var wireframe: ManageAgreementWireframeInput?
  
  struct Input {
    let viewWillAppear: Observable<Void>
    let agreement: Observable<Bool>
    let submit: Observable<Void>
  }
  
  struct Output {
    let isError: Driver<Error>
    let isProgress: Driver<Bool>
    let documents: Observable<[AgreePDFDocument]>
  }

  private let disposeBag = DisposeBag()
  
  private let progressLinker = PublishSubject<Bool>()
  private let errorLinker = PublishSubject<Error>()
  private let documents = PublishSubject<[AgreePDFDocument]>()

  func transform(input: Input) -> Output {
    input.viewWillAppear.subscribe(
      onNext: {[weak self] in
        self?.progressLinker.onNext(true)
        self?.interactor?.fetchDocuments()
      },
      onError: {[weak self] in self?.errorLinker.onNext($0)}
    ).disposed(by: disposeBag)
    
    input.submit.withLatestFrom(input.agreement) {$1}
      .asObservable().subscribe(onNext: {[weak self] in
        self?.progressLinker.onNext(true)
        self?.interactor?.agreement($0)
      }).disposed(by: disposeBag)
    
    return Output(
      isError: errorLinker.asDriverOnErrorJustComplete(),
      isProgress: progressLinker.asDriverOnErrorJustComplete(),
      documents: documents.asObservable()
    )
  }
}

// MARK: ManageAgreement interactor output interface
extension ManageAgreementPresenter: ManageAgreementInteractorOutput {
  func setDocuments(with documents: [AgreePDFDocument]) {
    progressLinker.onNext(false)
    self.documents.onNext(documents)
  }
  
  func resultAgreement() {
    progressLinker.onNext(false)
    wireframe?.goNewRegistration()
  }
  
  func setError(with error: Error) {
    progressLinker.onNext(false)
    errorLinker.onNext(error)
  }
}