RSSuper/iOS/RSSuper/UI/FeedListView.swift

import SwiftUI

struct FeedListView: View {
    @StateObject private var viewModel: FeedViewModel
    @State private var selectedFeedItem: FeedItem?
    @State private var showError: Bool = false
    @State private var errorMessage: String = ""
    
    private let feedService: FeedServiceProtocol
    
    init(feedService: FeedServiceProtocol = FeedService()) {
        self.feedService = feedService
        _viewModel = StateObject(wrappedValue: FeedViewModel(feedService: feedService))
    }
    
    var body: some View {
        NavigationSplitView {
            List {
                switch viewModel.feedState {
                case .idle:
                    ContentUnavailableView("No Feed", systemImage: "rss")
                        .padding()
                
                case .loading:
                    ProgressView("Loading...")
                        .padding()
                
                case .success(let items):
                    ForEach(items) { item in
                        FeedItemRow(feedItem: item)
                            .onTapGesture {
                                selectedFeedItem = item
                            }
                    }
                    .onDelete(perform: deleteItems)
                
                case .error(let error):
                    VStack {
                        Text("Error loading feed")
                            .foregroundColor(.red)
                        Text(error)
                            .font(.caption)
                        Button("Retry") {
                            refresh()
                        }
                    }
                    .padding()
                }
            }
            .navigationTitle("Feeds")
            .toolbar {
                ToolbarItem(placement: .navigationBarTrailing) {
                    Button(action: refresh) {
                        Image(systemName: "arrow.clockwise")
                    }
                }
            }
            .refreshable {
                refresh()
            }
            .sheet(item: $selectedFeedItem) { item in
                FeedDetailView(feedItem: item, feedService: feedService)
            }
            .alert("Error", isPresented: $showError) {
                Button("OK", role: .cancel) { errorMessage = "" }
            } message: {
                Text(errorMessage)
            }
        }
    }
    
    private func refresh() {
        if let subscriptionId = viewModel.currentSubscriptionId {
            viewModel.refresh(subscriptionId: subscriptionId)
        }
    }
    
   private func deleteItems(offsets: IndexSet) {
        guard let subscriptionId = viewModel.currentSubscriptionId else { return }
        
        Task {
            let items = viewModel.feedItems
            for index in offsets {
                let item = items[index]
                _ = feedService.markItemAsRead(itemId: item.id)
            }
            viewModel.refresh(subscriptionId: subscriptionId)
        }
    }
}

struct FeedItemRow: View {
    let feedItem: FeedItem
    
    var body: some View {
        HStack {
            VStack(alignment: .leading) {
                Text(feedItem.title)
                    .font(.headline)
                    .lineLimit(2)
                
                if let author = feedItem.author {
                    Text(author)
                        .font(.subheadline)
                        .foregroundColor(.secondary)
                }
                
                if let published = feedItem.published {
                    Text(published, format: Date.FormatStyle(date: .abbreviated, time: .shortened))
                        .font(.caption)
                        .foregroundColor(.secondary)
                }
            }
            Spacer()
            if !feedItem.read {
                Circle()
                    .fill(Color.blue)
                    .frame(width: 8, height: 8)
            }
        }
        .padding(.vertical, 4)
    }
}

#Preview {
    FeedListView()
}