import SwiftUI
import ComposableArchitecture

// MARK: - BackgroundView
struct BackgroundView: View {
    var body: some View {
        Image("bg")
            .resizable()
            .aspectRatio(contentMode: .fill)
            .frame(maxWidth: .infinity, maxHeight: .infinity)
            .clipped()
            .ignoresSafeArea(.all)
    }
}

// MARK: - TopBarView
struct TopBarView: View {
    let onEditTapped: () -> Void
    
    var body: some View {
        ZStack {
            HStack {
                Spacer(minLength: 0)
                Text(LocalizedString("feedList.title", comment: "Enjoy your Life Time"))
                    .font(.system(size: 22, weight: .semibold))
                    .foregroundColor(.white)
                    .frame(maxWidth: .infinity, alignment: .center)
                Spacer(minLength: 0)
            }
            HStack {
                Spacer(minLength: 0)
                Button(action: onEditTapped) {
                    Image("add icon")
                        .resizable()
                        .frame(width: 40, height: 40)
                }
            }
        }
        .padding(.horizontal, 20)
    }
}

// MARK: - LoadingView
private struct FeedListLoadingView: View {
    var body: some View {
        ProgressView()
            .progressViewStyle(CircularProgressViewStyle(tint: .white))
            .padding(.top, 20)
    }
}

// MARK: - ErrorView
struct ErrorView: View {
    let error: String
    
    var body: some View {
        Text(error)
            .font(.system(size: 14))
            .foregroundColor(.red)
            .multilineTextAlignment(.center)
            .padding(.horizontal, 20)
            .padding(.top, 20)
    }
}

// MARK: - EmptyView
struct EmptyView: View {
    var body: some View {
        Text(LocalizedString("feedList.empty", comment: "暂无动态"))
            .font(.system(size: 16))
            .foregroundColor(.white.opacity(0.7))
            .padding(.top, 20)
    }
}

// MARK: - MomentCardView
struct MomentCardView: View {
    let moment: MomentsInfo
    let allMoments: [MomentsInfo]
    let index: Int
    let onImageTap: ([String], Int) -> Void
    let onTap: () -> Void
    let onLikeTap: (Int, Int, Int, Int) -> Void
    let onLoadMore: () -> Void
    let isLastItem: Bool
    let hasMore: Bool
    let isLoadingMore: Bool
    let isLikeLoading: Bool
    
    var body: some View {
        VStack(spacing: 16) {
            OptimizedDynamicCardView(
                moment: moment,
                allMoments: allMoments,
                currentIndex: index,
                onImageTap: onImageTap,
                onLikeTap: onLikeTap,
                onCardTap: onTap,
                isDetailMode: false,
                isLikeLoading: isLikeLoading
            )
            
            // 上拉加载更多触发点
            if isLastItem && hasMore && !isLoadingMore {
                Color.clear
                    .frame(height: 1)
                    .onAppear {
                        onLoadMore()
                    }
            }
        }
    }
}

// MARK: - MomentsListView
struct MomentsListView: View {
    let moments: [MomentsInfo]
    let hasMore: Bool
    let isLoadingMore: Bool
    let onImageTap: ([String], Int) -> Void
    let onMomentTap: (MomentsInfo) -> Void
    let onLikeTap: (Int, Int, Int, Int) -> Void
    let onLoadMore: () -> Void
    let onRefresh: () -> Void
    let likeLoadingDynamicIds: Set<Int>
    
    var body: some View {
        ScrollView {
            LazyVStack(spacing: 16) {
                ForEach(Array(moments.enumerated()), id: \.element.dynamicId) { index, moment in
                    MomentCardView(
                        moment: moment,
                        allMoments: moments,
                        index: index,
                        onImageTap: onImageTap,
                        onTap: {
                            onMomentTap(moment)
                        },
                        onLikeTap: onLikeTap,
                        onLoadMore: onLoadMore,
                        isLastItem: index == moments.count - 1,
                        hasMore: hasMore,
                        isLoadingMore: isLoadingMore,
                        isLikeLoading: likeLoadingDynamicIds.contains(moment.dynamicId)
                    )
                }
                
                // 加载更多指示器
                if isLoadingMore {
                    ProgressView()
                        .progressViewStyle(CircularProgressViewStyle(tint: .white))
                        .padding(.vertical, 8)
                }
                
                // 新增底部间距
                Color.clear.frame(height: 120)
            }
            .padding(.horizontal, 16)
            .padding(.top, 10)
            .padding(.bottom, 20)
        }
        .refreshable {
            onRefresh()
        }
    }
}

// MARK: - FeedListContentView
struct FeedListContentView: View {
    let store: StoreOf<FeedListFeature>
    @Binding var previewItem: PreviewItem?
    @Binding var previewCurrentIndex: Int
    
    var body: some View {
        if store.isLoading {
            FeedListLoadingView()
        } else if let error = store.error {
            ErrorView(error: error)
        } else if store.moments.isEmpty {
            EmptyView()
        } else {
            MomentsListView(
                moments: store.moments,
                hasMore: store.hasMore,
                isLoadingMore: store.isLoadingMore,
                onImageTap: { images, tappedIndex in
                    previewCurrentIndex = tappedIndex
                    previewItem = PreviewItem(images: images, index: tappedIndex)
                },
                onMomentTap: { moment in
                    store.send(.showDetail(moment))
                },
                onLikeTap: { dynamicId, uid, likedUid, worldId in
                    store.send(.likeDynamic(dynamicId, uid, likedUid, worldId))
                },
                onLoadMore: {
                    store.send(.loadMore)
                },
                onRefresh: {
                    store.send(.reload)
                },
                likeLoadingDynamicIds: store.likeLoadingDynamicIds
            )
        }
    }
}

struct FeedListView: View {
    let store: StoreOf<FeedListFeature>
    // 新增：图片预览状态
    @State private var previewItem: PreviewItem? = nil
    @State private var previewCurrentIndex: Int = 0
    
    var body: some View {
        WithViewStore(store, observe: { $0 }) { viewStore in
            GeometryReader { geometry in
                ZStack {
                    // 背景
                    BackgroundView()
                    
                    VStack(alignment: .center, spacing: 0) {
                        // 顶部栏
                        TopBarView {
                            store.send(.editFeedButtonTapped)
                        }
                        
                        // 其他内容
                        Image("Volume")
                            .frame(width: 56, height: 41)
                            .padding(.top, 16)
                        
                        Text(LocalizedString("feedList.slogan", comment: "The disease is like a cruel ruler,\nand time is our most precious treasure.\nEvery moment we live is a victory\nagainst the inevitable."))
                            .font(.system(size: 16))
                            .multilineTextAlignment(.leading)
                            .foregroundColor(.white.opacity(0.9))
                            .padding(.horizontal, 30)
                            .padding(.bottom, 30)
                        
                        // 动态内容列表
                        FeedListContentView(
                            store: store,
                            previewItem: $previewItem,
                            previewCurrentIndex: $previewCurrentIndex
                        )
                        
                        Spacer()
                    }
                }
            }
            .onAppear {
                store.send(.onAppear)
            }
            .refreshable {
                store.send(.reload)
            }
            // 新增：编辑动态页面
            .sheet(isPresented: viewStore.binding(get: \.isEditFeedPresented, send: { _ in .editFeedDismissed })) {
                let createFeedStore = Store(
                    initialState: CreateFeedFeature.State()
                ) {
                    CreateFeedFeature()
                }
                
                CreateFeedView(store: createFeedStore)
                    .onReceive(NotificationCenter.default.publisher(for: .init("CreateFeedPublishSuccess"))) { _ in
                        store.send(.createFeedPublishSuccess)
                    }
                    .onReceive(NotificationCenter.default.publisher(for: .init("CreateFeedDismiss"))) { _ in
                        store.send(.editFeedDismissed)
                    }
            }
            // 新增：详情页导航
            .navigationDestination(isPresented: viewStore.binding(get: \.showDetail, send: { _ in .detailDismissed })) {
                if let selectedMoment = viewStore.selectedMoment {
                    DetailView(
                        store: Store(
                            initialState: DetailFeature.State(moment: selectedMoment)
                        ) {
                            DetailFeature()
                        }
                    )
                }
            }
            // 新增：图片预览弹窗
            .fullScreenCover(item: $previewItem) { item in
                ImagePreviewPager(images: item.images as [String], currentIndex: $previewCurrentIndex) {
                    previewItem = nil
                }
            }
        }
    }
}