import SwiftUI

/// 金币明细(流水)。从福利页金币卡进入。
struct CoinHistoryView: View {
    @State private var vm = CoinHistoryViewModel()

    var body: some View {
        Group {
            if vm.isLoading && vm.items.isEmpty {
                ProgressView().frame(maxWidth: .infinity, maxHeight: .infinity)
            } else if vm.loaded && vm.items.isEmpty {
                ContentUnavailableView("还没有金币记录", systemImage: "circle.hexagongrid")
            } else {
                List {
                    ForEach(vm.items) { tx in
                        coinRow(tx)
                    }
                    if vm.hasMore {
                        HStack { Spacer(); ProgressView(); Spacer() }
                            .onAppear { Task { await vm.loadMore() } }
                    }
                }
                .listStyle(.plain)
                .refreshable { await vm.loadFirst() }
            }
        }
        .navigationTitle("金币明细")
        .navigationBarTitleDisplayMode(.inline)
        .task { if !vm.loaded { await vm.loadFirst() } }
    }

    private func coinRow(_ tx: CoinTransactionDTO) -> some View {
        HStack {
            VStack(alignment: .leading, spacing: 2) {
                Text(WelfareCatalog.coinBizText(tx)).font(.subheadline)
                Text(AppDate.friendly(tx.createdAt))
                    .font(.caption2).foregroundStyle(.secondary)
            }
            Spacer()
            Text("\(tx.amount > 0 ? "+" : "")\(tx.amount)")
                .font(.subheadline.bold())
                .foregroundStyle(tx.amount > 0 ? AppColors.coin : AppColors.gray600)
        }
        .padding(.vertical, 2)
    }
}