AppleMusicFeed.swift

import SwiftUI
import CompositionalList

struct FeedView: View {
    
    @ObservedObject private var remote = ItunesRemote()
    @State var selectedItem: FeedItemViewModel?

    var body: some View {
        NavigationView {
            /// 5
            if remote.feedItems.isEmpty {
                ActivityIndicator()
            } else {
                CompositionalList(remote.feedItems) { model, indexPath in
                    /// 1
                    Group {
                        switch indexPath.section {
                        case 0, 2, 3:
                            TileInfo(artworkViewModel: model)
                        case 1:
                            ListItem(artworkViewModel: model)
                        default:
                            ArtWork(artworkViewModel: model)
                        }
                    }
                }.sectionHeader { sectionIdentifier, kind, indexPath in
                    /// 2
                    TitleHeaderView(title: sectionIdentifier.rawValue)
                }
                .selectedItem {
                    /// 3
                    selectedItem = $0
                }
                /// 4
                .customLayout(.composed())
                .sheet(item: $selectedItem) { item in
                    ItunesFeedItemDetailView(viewModel: item)
                }
                .navigationBarTitle("Apple Music")
            }
        }
        .onAppear {
            remote.fetchItems(.appleMusic(feedType: .topSongs(genre: .all), limit: 200))
        }
    }
}