import SwiftUI
import CoreData
import QRCode
internal import SwiftImageReadWrite

struct QRCodeDetailView: View {
    let historyItem: HistoryItem
    @StateObject private var coreDataManager = CoreDataManager.shared
    @State private var qrCodeImage: UIImage?
    @State private var showingShareSheet = false
    @State private var showingAlert = false
    @State private var alertMessage = ""
    
    var body: some View {
        ScrollView {
            VStack(spacing: 20) {
                // 二维码图片
                qrCodeImageView
                
                // 二维码类型信息
                qrCodeTypeSection
                
                // 解析后的详细信息
                parsedInfoSection
                
                // 原始内容
                originalContentSection
                
                // 操作按钮
                actionButtonsSection
            }
            .padding()
        }
        .navigationTitle("二维码详情")
        .navigationBarTitleDisplayMode(.inline)
        .toolbar {
            ToolbarItem(placement: .navigationBarTrailing) {
                Button(action: {
                    showingShareSheet = true
                }) {
                    Image(systemName: "square.and.arrow.up")
                }
            }
        }
        .onAppear {
            generateQRCodeImage()
        }
        .sheet(isPresented: $showingShareSheet) {
            ShareSheet(activityItems: [historyItem.content ?? ""])
        }
        .alert("提示", isPresented: $showingAlert) {
            Button("确定") { }
        } message: {
            Text(alertMessage)
        }
    }
    
    // MARK: - 二维码图片视图
    private var qrCodeImageView: some View {
        VStack(spacing: 16) {
            if let qrCodeImage = qrCodeImage {
                Image(uiImage: qrCodeImage)
                    .resizable()
                    .aspectRatio(contentMode: .fit)
                    .frame(width: 200, height: 200)
                    .cornerRadius(12)
                    .shadow(radius: 8)
            } else {
                RoundedRectangle(cornerRadius: 12)
                    .fill(Color.gray.opacity(0.3))
                    .frame(width: 200, height: 200)
                    .overlay(
                        ProgressView()
                            .scaleEffect(1.5)
                    )
            }
            
            Text("扫描此二维码")
                .font(.caption)
                .foregroundColor(.secondary)
        }
    }
    
    // MARK: - 二维码类型信息
    private var qrCodeTypeSection: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                Image(systemName: "qrcode")
                    .font(.title2)
                    .foregroundColor(.blue)
                
                Text("二维码类型")
                    .font(.headline)
                
                Spacer()
            }
            
            if let qrCodeTypeString = historyItem.qrCodeType,
               let qrCodeType = QRCodeType(rawValue: qrCodeTypeString) {
                HStack {
                    Image(systemName: qrCodeType.icon)
                        .font(.title3)
                        .foregroundColor(.orange)
                    
                    Text(qrCodeType.displayName)
                        .font(.title3)
                        .fontWeight(.medium)
                    
                    Spacer()
                }
                .padding()
                .background(Color.orange.opacity(0.1))
                .cornerRadius(8)
            }
        }
        .padding()
        .background(Color(.systemBackground))
        .cornerRadius(12)
        .shadow(radius: 2)
    }
    
    // MARK: - 解析后的详细信息
    private var parsedInfoSection: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                Image(systemName: "info.circle")
                    .font(.title2)
                    .foregroundColor(.green)
                
                Text("解析信息")
                    .font(.headline)
                
                Spacer()
            }
            
            if let content = historyItem.content {
                let parsedData = QRCodeParser.parseQRCode(content)
                
                VStack(alignment: .leading, spacing: 8) {
                    HStack {
                        Image(systemName: parsedData.icon)
                            .font(.title3)
                            .foregroundColor(.green)
                        
                        Text(parsedData.title)
                            .font(.title3)
                            .fontWeight(.medium)
                        
                        Spacer()
                    }
                    
                    if let subtitle = parsedData.subtitle {
                        Text(subtitle)
                            .font(.body)
                            .foregroundColor(.secondary)
                            .multilineTextAlignment(.leading)
                    }
                }
                .padding()
                .background(Color.green.opacity(0.1))
                .cornerRadius(8)
            }
        }
        .padding()
        .background(Color(.systemBackground))
        .cornerRadius(12)
        .shadow(radius: 2)
    }
    
    // MARK: - 原始内容
    private var originalContentSection: some View {
        VStack(alignment: .leading, spacing: 12) {
            HStack {
                Image(systemName: "doc.text")
                    .font(.title2)
                    .foregroundColor(.purple)
                
                Text("原始内容")
                    .font(.headline)
                
                Spacer()
            }
            
            if let content = historyItem.content {
                ScrollView {
                    Text(content)
                        .font(.system(.body, design: .monospaced))
                        .foregroundColor(.secondary)
                        .multilineTextAlignment(.leading)
                        .padding()
                        .frame(maxWidth: .infinity, alignment: .leading)
                }
                .frame(maxHeight: 200)
                .background(Color.purple.opacity(0.1))
                .cornerRadius(8)
            }
        }
        .padding()
        .background(Color(.systemBackground))
        .cornerRadius(12)
        .shadow(radius: 2)
    }
    
    // MARK: - 操作按钮
    private var actionButtonsSection: some View {
        VStack(spacing: 12) {
            // 收藏按钮
            Button(action: toggleFavorite) {
                HStack {
                    Image(systemName: historyItem.isFavorite ? "heart.fill" : "heart")
                        .foregroundColor(historyItem.isFavorite ? .red : .gray)
                    
                    Text(historyItem.isFavorite ? "取消收藏" : "收藏")
                        .fontWeight(.medium)
                }
                .frame(maxWidth: .infinity)
                .padding()
                .background(historyItem.isFavorite ? Color.red.opacity(0.1) : Color.gray.opacity(0.1))
                .foregroundColor(historyItem.isFavorite ? .red : .gray)
                .cornerRadius(10)
            }
            
            // 复制内容按钮
            Button(action: copyContent) {
                HStack {
                    Image(systemName: "doc.on.doc")
                        .foregroundColor(.blue)
                    
                    Text("复制内容")
                        .fontWeight(.medium)
                }
                .frame(maxWidth: .infinity)
                .padding()
                .background(Color.blue.opacity(0.1))
                .foregroundColor(.blue)
                .cornerRadius(10)
            }
            
            // 打开链接按钮（如果是URL类型）
            if let content = historyItem.content, canOpenURL(content) {
                Button(action: { openURL(content) }) {
                    HStack {
                        Image(systemName: "arrow.up.right.square")
                            .foregroundColor(.green)
                        
                        Text("打开链接")
                            .fontWeight(.medium)
                    }
                    .frame(maxWidth: .infinity)
                    .padding()
                    .background(Color.green.opacity(0.1))
                    .foregroundColor(.green)
                    .cornerRadius(10)
                }
            }
        }
        .padding()
        .background(Color(.systemBackground))
        .cornerRadius(12)
        .shadow(radius: 2)
    }
    
    // MARK: - 生成二维码图片
    private func generateQRCodeImage() {
        guard let content = historyItem.content else { return }
        
        do {
            let imageData = try QRCode.build
               .text(content)
               .quietZonePixelCount(3)
               .foregroundColor(CGColor(srgbRed: 1, green: 0, blue: 0.6, alpha: 1))
               .backgroundColor(CGColor(srgbRed: 0, green: 0, blue: 0.2, alpha: 1))
               .background.cornerRadius(3)
               .onPixels.shape(QRCode.PixelShape.CurvePixel())
               .eye.shape(QRCode.EyeShape.Teardrop())
               .generate.image(dimension: 600, representation: .png())
            
            self.qrCodeImage = UIImage(data: imageData)
            
        } catch {
            print("生成二维码失败: \(error)")
        }
    }
    
    // MARK: - 切换收藏状态
    private func toggleFavorite() {
        historyItem.isFavorite.toggle()
        coreDataManager.save()
        
        let message = historyItem.isFavorite ? "已添加到收藏" : "已取消收藏"
        alertMessage = message
        showingAlert = true
    }
    
    // MARK: - 复制内容
    private func copyContent() {
        if let content = historyItem.content {
            UIPasteboard.general.string = content
            alertMessage = "内容已复制到剪贴板"
            showingAlert = true
        }
    }
    
    // MARK: - 检查是否可以打开URL
    private func canOpenURL(_ string: String) -> Bool {
        guard let url = URL(string: string) else { return false }
        return UIApplication.shared.canOpenURL(url)
    }
    
    // MARK: - 打开URL
    private func openURL(_ string: String) {
        guard let url = URL(string: string) else { return }
        UIApplication.shared.open(url)
    }
}

// MARK: - 分享表单
struct ShareSheet: UIViewControllerRepresentable {
    let activityItems: [Any]
    
    func makeUIViewController(context: Context) -> UIActivityViewController {
        let controller = UIActivityViewController(activityItems: activityItems, applicationActivities: nil)
        return controller
    }
    
    func updateUIViewController(_ uiViewController: UIActivityViewController, context: Context) {}
}

#Preview("Wi‑Fi") {
    let ctx = PreviewData.context
    let item = PreviewData.wifiSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

#Preview("URL") {
    let ctx = PreviewData.context
    let item = PreviewData.urlSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

#Preview("SMS") {
    let ctx = PreviewData.context
    let item = PreviewData.smsSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

#Preview("vCard") {
    let ctx = PreviewData.context
    let item = PreviewData.vcardSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

#Preview("Instagram") {
    let ctx = PreviewData.context
    let item = PreviewData.instagramSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

#Preview("Text") {
    let ctx = PreviewData.context
    let item = PreviewData.textSample(in: ctx)
    return NavigationView { QRCodeDetailView(historyItem: item) }
}

// MARK: - Preview Data
private enum PreviewData {
    static let context: NSManagedObjectContext = {
        let container = NSPersistentContainer(name: "MyQrCode")
        let description = NSPersistentStoreDescription()
        description.type = NSInMemoryStoreType
        container.persistentStoreDescriptions = [description]
        container.loadPersistentStores { _, _ in }
        return container.viewContext
    }()

    private static func makeBaseItem(in context: NSManagedObjectContext, content: String, qrType: QRCodeType, favorite: Bool = false) -> HistoryItem {
        let item = HistoryItem(context: context)
        item.id = UUID()
        item.content = content
        item.dataType = DataType.qrcode.rawValue
        item.dataSource = DataSource.created.rawValue
        item.createdAt = Date()
        item.isFavorite = favorite
        item.qrCodeType = qrType.rawValue
        return item
    }

    static func wifiSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = "WIFI:T:WPA;S:MyNetwork;P:MyPassword;;"
        return makeBaseItem(in: context, content: content, qrType: .wifi, favorite: true)
    }

    static func urlSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = "https://www.example.com"
        return makeBaseItem(in: context, content: content, qrType: .url)
    }

    static func smsSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = "SMSTO:+8613800138000:Hello"
        return makeBaseItem(in: context, content: content, qrType: .sms)
    }

    static func vcardSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = """
        BEGIN:VCARD
        VERSION:3.0
        FN:John Doe
        TEL:+1234567890
        EMAIL:example@example.com
        END:VCARD
        """.trimmingCharacters(in: .whitespacesAndNewlines)
        return makeBaseItem(in: context, content: content, qrType: .vcard)
    }

    static func instagramSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = "https://www.instagram.com/example_user/"
        return makeBaseItem(in: context, content: content, qrType: .instagram)
    }

    static func textSample(in context: NSManagedObjectContext) -> HistoryItem {
        let content = "Hello, this is a text message!"
        return makeBaseItem(in: context, content: content, qrType: .text)
    }
}