import SwiftUI

struct MainChatView: View {
    let onTapCanCharge: () -> Void
    let onTapSearch: () -> Void

    @StateObject private var viewModel = MainChatViewModel()

    var body: some View {
        VStack(spacing: 0) {
            DefaultTitleBar(title: MainTab.chat.title) {
                HStack(spacing: SodaSpacing.s14) {
                    Image("ic_bar_cash")
                        .onTapGesture { onTapCanCharge() }

                    Image("ic_bar_search")
                        .onTapGesture { onTapSearch() }
                }
            }

            CapsuleTabBar(
                items: MainChatFilter.allCases,
                selectedItem: selectedFilterBinding,
                title: { $0.title }
            )

            chatListContent
                .frame(maxWidth: .infinity, maxHeight: .infinity)
        }
        .background(Color.black.ignoresSafeArea())
        .onAppear { viewModel.fetchFirstPageIfNeeded() }
        .sodaToast(
            isPresented: $viewModel.isShowPopup,
            message: viewModel.errorMessage,
            autohideIn: 2
        )
    }


    private var selectedFilterBinding: Binding<MainChatFilter> {
        Binding(
            get: { viewModel.selectedFilter },
            set: { viewModel.applyFilter($0) }
        )
    }

    @ViewBuilder
    private var chatListContent: some View {
        if viewModel.isLoading && viewModel.rooms.isEmpty {
            ProgressView()
                .progressViewStyle(.circular)
                .tint(Color.soda400)
                .frame(maxWidth: .infinity, maxHeight: .infinity)
        } else if viewModel.shouldShowEmptyState {
            Text(I18n.MainChat.emptyStateMessage)
                .appFont(size: 16, weight: .medium)
                .foregroundColor(Color.gray500)
                .frame(maxWidth: .infinity, maxHeight: .infinity)
        } else {
            ScrollView(showsIndicators: false) {
                LazyVStack(spacing: 0) {
                    ForEach(viewModel.rooms) { room in
                        MainChatRoomListItem(room: room) { roomId, chatType in
                            handleChatRoomTap(roomId: roomId, chatType: chatType)
                        }
                        .onAppear {
                            viewModel.fetchNextPageIfNeeded(currentItem: room)
                        }
                    }

                    if viewModel.isLoadingNextPage {
                        ProgressView()
                            .progressViewStyle(.circular)
                            .tint(Color.soda400)
                            .padding(.vertical, SodaSpacing.s20)
                    }
                }
                .padding(.top, 0)
            }
        }
    }

    private func handleChatRoomTap(roomId: Int, chatType: String) {
        guard roomId > 0 else { return }

        if chatType == "AI" {
            AppState.shared.setAppStep(step: .chatRoom(id: roomId))
        } else if chatType == "DM" {
            AppState.shared.setAppStep(step: .userCreatorChatRoom(roomId: roomId))
        }
    }
}

struct MainChatView_Previews: PreviewProvider {
    static var previews: some View {
        MainChatView(onTapCanCharge: {}, onTapSearch: {})
    }
}