import SwiftUI

/// 我的比价记录(每次比价的概要,含成功/失败)。数据由安卓端比价后上报,iOS 只读。
struct CompareRecordsView: View {
    @State private var vm = CompareRecordsViewModel()

    var body: some View {
        Group {
            if vm.isLoading && vm.records.isEmpty {
                ProgressView().frame(maxWidth: .infinity, maxHeight: .infinity)
            } else if vm.loaded && vm.records.isEmpty {
                ContentUnavailableView {
                    Label("还没有比价记录", systemImage: "list.bullet.rectangle")
                } description: {
                    Text(vm.errorMessage ?? "在安卓 App 上完成比价后,记录会自动同步到这里")
                }
            } else {
                List {
                    ForEach(vm.records) { record in
                        CompareRecordRow(record: record)
                            .listRowSeparator(.hidden)
                    }
                    if vm.hasMore {
                        HStack { Spacer(); ProgressView(); Spacer() }
                            .listRowSeparator(.hidden)
                            .onAppear { Task { await vm.loadMore() } }
                    }
                }
                .listStyle(.plain)
                .refreshable { await vm.loadFirst() }
            }
        }
        .navigationTitle("我的比价记录")
        .navigationBarTitleDisplayMode(.inline)
        .task { if !vm.loaded { await vm.loadFirst() } }
    }
}

private struct CompareRecordRow: View {
    let record: ComparisonRecordDTO

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            HStack {
                Text(record.storeName ?? "比价记录")
                    .font(.headline)
                    .lineLimit(1)
                Spacer()
                Text(AppDate.friendly(record.createdAt))
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }

            if record.status == "success" {
                HStack(spacing: 6) {
                    if let sp = record.sourcePlatformName, let spc = record.sourcePriceCents {
                        Text("\(sp) \(spc.centsToYuanText)")
                            .strikethrough(record.isSourceBest != true)
                            .foregroundStyle(.secondary)
                    }
                    Image(systemName: "arrow.right").font(.caption2).foregroundStyle(.secondary)
                    if let bp = record.bestPlatformName, let bpc = record.bestPriceCents {
                        Text("\(bp) \(bpc.centsToYuanText)").bold()
                    }
                }
                .font(.subheadline)

                if let saved = record.savedAmountCents, saved > 0 {
                    Text("省 \(saved.centsToYuanText)")
                        .font(.subheadline.bold())
                        .foregroundStyle(AppColors.success)
                } else if record.isSourceBest == true {
                    Text("源平台已是最低价")
                        .font(.caption)
                        .foregroundStyle(.secondary)
                }
            } else {
                Text(record.information ?? "本次比价未完成")
                    .font(.subheadline)
                    .foregroundStyle(.secondary)
            }
        }
        .padding(.vertical, 6)
    }
}