import Foundation
import Combine

final class MainContentRecommendationViewModel: ObservableObject {
    private let repository = MainContentRecommendationRepository()
    private var subscription = Set<AnyCancellable>()

    @Published var isLoading = false
    @Published var isShowPopup = false
    @Published var errorMessage = ""
    @Published var recommendations: AudioRecommendationsResponse?
    @Published var hasLoaded = false

    var emptyStateMessage: String {
        if !errorMessage.isEmpty {
            return errorMessage
        }

        return I18n.MainContentRecommendation.emptyStateMessage
    }

    var shouldShowEmptyState: Bool {
        hasLoaded && !isLoading && (recommendations?.isEmpty ?? true)
    }

    func fetchRecommendations() {
        guard !isLoading else { return }

        isLoading = true

        repository.getAudioRecommendations()
            .sink { [weak self] result in
                guard let self else { return }

                switch result {
                case .finished:
                    DEBUG_LOG("finish")
                case .failure(let error):
                    ERROR_LOG(error.localizedDescription)
                    self.errorMessage = I18n.MainContentRecommendation.loadFailedMessage
                    self.isShowPopup = true
                    self.isLoading = false
                    self.hasLoaded = true
                }
            } receiveValue: { [weak self] response in
                guard let self else { return }

                let responseData = response.data

                do {
                    let jsonDecoder = JSONDecoder()
                    let decoded = try jsonDecoder.decode(ApiResponse<AudioRecommendationsResponse>.self, from: responseData)

                    if let data = decoded.data, decoded.success {
                        self.errorMessage = ""
                        self.recommendations = data
                    } else {
                        self.errorMessage = decoded.message ?? I18n.MainContentRecommendation.loadFailedMessage
                        self.isShowPopup = true
                    }
                } catch {
                    ERROR_LOG(error.localizedDescription)
                    self.errorMessage = I18n.MainContentRecommendation.loadFailedMessage
                    self.isShowPopup = true
                }

                self.isLoading = false
                self.hasLoaded = true
            }
            .store(in: &subscription)
    }
}