// 
// MIT License
//
// Copyright (c) 2018-2019 Open Zesame (https://github.com/OpenZesame)
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//

import Zesame

import RxSwift
import UIKit
import RxCocoa

enum BackUpRevealedKeyPairUserAction {
    case finish
}

private typealias € = L10n.Scene.BackUpRevealedKeyPair

final class BackUpRevealedKeyPairViewModel: BaseViewModel<
    BackUpRevealedKeyPairUserAction,
    BackUpRevealedKeyPairViewModel.InputFromView,
    BackUpRevealedKeyPairViewModel.Output
> {

    private let keyPair: KeyPair

    init(keyPair: KeyPair) {
        self.keyPair = keyPair
    }

    // swiftlint:disable:next function_body_length
    override func transform(input: Input) -> Output {
        func userDid(_ step: NavigationStep) {
            navigator.next(step)
        }

        let keyPair = Driver.just(self.keyPair)

        let privateKey = keyPair.map { $0.privateKey.asHexStringLength64() }
        let publicKeyUncompressed = keyPair.map { $0.publicKey.hex.uncompressed }

        bag <~ [
            input.fromController.rightBarButtonTrigger
                .do(onNext: { userDid(.finish) })
                .drive(),

            input.fromView.copyPrivateKeyTrigger.withLatestFrom(privateKey) { $1 }
                .do(onNext: {
                    UIPasteboard.general.string = $0
                    input.fromController.toastSubject.onNext(Toast(€.Event.Toast.didCopyPrivateKey))
                }).drive(),

            input.fromView.copyPublicKeyTrigger.withLatestFrom(publicKeyUncompressed) { $1 }
                .do(onNext: {
                    UIPasteboard.general.string = $0
                    input.fromController.toastSubject.onNext(Toast(€.Event.Toast.didCopyPublicKey))
                }).drive()
        ]

        return Output(
            privateKey: privateKey,
            publicKeyUncompressed: publicKeyUncompressed
        )
    }
}

extension BackUpRevealedKeyPairViewModel {

    struct InputFromView {
        let copyPrivateKeyTrigger: Driver<Void>
        let copyPublicKeyTrigger: Driver<Void>
    }

    struct Output {
        let privateKey: Driver<String>
        let publicKeyUncompressed: Driver<String>
    }
}

