import SwiftUI

struct PostDetailsCarouselItemView: View {
  var post: BooruPost
  var index: Int
  @Binding var loadingStage: BooruPostLoadingState
  var imageURL: (BooruPost) -> URL?
  private var systemBackgroundColor: Color {
    #if os(iOS)
      return Color(.systemBackground)
    #elseif os(macOS)
      return Color(.windowBackgroundColor)
    #else
      return Color.gray
    #endif
  }

  var body: some View {
    ZStack {
      PostDetailsImageView(
        url: post.previewURL,
        loadingStage: $loadingStage
      ) {
        GeometryReader { geometry in
          ProgressView()
            .frame(width: geometry.size.width, height: geometry.size.height)
        }
      }

      PostDetailsImageView(
        url: imageURL(post),
        loadingStage: $loadingStage,
        finalLoadingState: .loaded,
        post: post
      )
      .background(
        loadingStage == .loaded ? systemBackgroundColor : Color.clear
      )
    }
    .tag(index)
  }
}