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import SwiftUI
struct PostDetailsCarouselView: View {
@EnvironmentObject var settings: SettingsManager
let posts: [BooruPost]
let focusedPost: BooruPost?
@Binding var loadingStage: BooruPostLoadingState
@State private var currentIndex: Int
private let cacheManager = ImageCacheManager.shared
@Binding var selectedPost: (post: BooruPost?, manager: BooruManager?)
init(
posts: [BooruPost],
loadingStage: Binding<BooruPostLoadingState>,
focusedPost: BooruPost? = nil,
selectedPost: Binding<(post: BooruPost?, manager: BooruManager?)>
) {
self.posts = posts
self.focusedPost = focusedPost
_loadingStage = loadingStage
_selectedPost = selectedPost
if let focused = focusedPost,
let index = posts.firstIndex(where: { $0.id == focused.id })
{
self._currentIndex = State(initialValue: index)
} else {
self._currentIndex = State(initialValue: 0)
}
}
func imageURL(post: BooruPost) -> URL? {
switch settings.detailViewQuality {
case .preview:
post.previewURL
case .sample:
post.sampleURL
case .original:
post.fileURL
}
}
var body: some View {
TabView(selection: $currentIndex) {
ForEach(Array(posts.enumerated()), id: \.offset) { index, post in
PostDetailsCarouselItemView(
index: index,
loadingStage: $loadingStage,
imageURL: imageURL,
selectedPost: $selectedPost
)
}
}
.onChange(of: currentIndex) {
guard let manager = selectedPost.manager else { return }
if currentIndex == posts.count - 1 { manager.loadNextPage() }
selectedPost.post = posts[currentIndex]
preloadNearbyImages()
}
.onAppear(perform: preloadNearbyImages)
#if !os(macOS)
.tabViewStyle(PageTabViewStyle(indexDisplayMode: .never))
#endif
}
private func preloadNearbyImages() {
let preloadRange = settings.preloadedCarouselImages
guard preloadRange > 0 else { return }
let startIndex = max(0, currentIndex - preloadRange)
let endIndex = min(posts.count - 1, currentIndex + preloadRange)
var urlsToPreload: [URL] = []
for index in startIndex...endIndex {
if let url = imageURL(post: posts[index]) {
urlsToPreload.append(url)
}
urlsToPreload.append(posts[index].previewURL)
}
cacheManager.preloadImages(urlsToPreload)
}
}
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