//
//  VIPSubscribeSheet.swift
//  Crush
//
//  Created by Leon on 2025/9/16.
//

class VIPSubscribeSheet: EGPopBaseView {
    var bgImageView: AutoRatioImageView!
    
    var titleLabel: UILabel!
    var closeButton: EPIconTertiaryButton!

    var privilegesContainer: UIView!
    var effectView: UIVisualEffectView!
    var layout = UICollectionViewFlowLayout()
    var cv: UICollectionView!
    var leftButton: EPIconTertiaryDarkButton!
    var rightButton: EPIconTertiaryDarkButton!

    var agreenmentContainer: UIView!

    var operateButton: StyleButton!

    var tableView: UITableView!
    
    // MARK: - Data Properties
    private var vipProducts: [VIPSubcribeProduct] = []
    private var privileges: [MemberPrivDict] = []
    private var currentRealCvIndex = 0
    /// 0~10
    private var currentPrivilegeIndex = 0
    private var selectedProductIndex = 0
    private var multiplier = 100 // 用于无限循环的倍数
    private var initialScrollCompleted = false // 标记是否已完成初始滚动

    init() {
        super.init(direction: .bottom)

        contentView.backgroundColor = .c.csbn
        contentLength = 693 + UIWindow.safeAreaBottom

        setupViews()
        setupData()
        setupEvent()
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    // MARK: - Data
    private func setupData(){
        
        // Group load Hud
        Hud.showIndicator()
        
        let group = DispatchGroup()
        group.enter()
        CLPurchase.shared.loadVIPTiersProducts { [weak self] products in
            group.leave()
            // 配置tableView中，充值档位
            if let products = products {
                self?.vipProducts = products
                DispatchQueue.main.async {
                    self?.tableView.reloadData()
                }
            }
        }
        
        group.enter()
        CLPurchase.shared.loadCurrentUserVipDetail { [weak self] output in
            group.leave()
            // get output.memberPrivList 权限展示列表，并显示在cv中
            if let output = output, let privileges = output.memberPrivList {
                self?.privileges = privileges
                DispatchQueue.main.async {
                    self?.cv.reloadData()
                    self?.updateNavigationButtons()
                    self?.initialScrollToMiddle() // 初始化时滚动到中间位置
                }
            }
        }
        
        group.notify(queue: .main) {
            // 所有 enter/leave 成对后，回调执行
            print("All completed")
            Hud.hideIndicator()
        }
    }
    
    private func setupEvent(){
        NotificationCenter.default.addObserver(self, selector: #selector(notifyVIPChanged(_:)), name: AppNotificationName.vipStateChange.notificationName, object: nil)
    }
    
    @objc private func notifyVIPChanged(_ noti: Notification){
        dismiss()
    }
    
    // MARK: - Functions
    private func updateNavigationButtons() {
        leftButton.isHidden = privileges.count <= 1
        rightButton.isHidden = privileges.count <= 1
    }
    
    private func scrollToPrivilege(at index: Int) {
        guard index >= 0 && index < privileges.count else { return }
        currentPrivilegeIndex = index
        
        // 计算当前应该滚动到的位置
        let totalItems = privileges.count * multiplier
        let middleStart = (totalItems / 2) - (totalItems / 2) % privileges.count
        let targetIndex = middleStart + index
        currentRealCvIndex = targetIndex
        let indexPath = IndexPath(item: targetIndex, section: 0)
        cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
    }
    
    private func initialScrollToMiddle() {
        guard privileges.count > 0 && !initialScrollCompleted else { return }
        let totalItems = privileges.count * multiplier
        let middleStart = (totalItems / 2) - (totalItems / 2) % privileges.count
        currentRealCvIndex = middleStart
        let indexPath = IndexPath(item: middleStart, section: 0)
        
        DispatchQueue.main.async {
            self.cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: false)
            self.initialScrollCompleted = true
        }
    }
    
    // MARK: - Action

    @objc private func leftButtonPressed() {
        guard privileges.count > 0 else { return }
        
        // 计算下一个目标位置（相邻位置）
        let nextRealIndex = currentRealCvIndex - 1
        
        // 检查是否需要边界处理
        let totalItems = privileges.count * multiplier
        let middleStart = (totalItems / 2) - (totalItems / 2) % privileges.count
        
        if nextRealIndex < 0 {
            // 如果超出左边界，跳转到右侧对应位置
            let targetIndex = totalItems - 1
            currentRealCvIndex = targetIndex
            currentPrivilegeIndex = targetIndex % privileges.count
            let indexPath = IndexPath(item: targetIndex, section: 0)
            cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
        } else {
            // 正常向左切换
            currentRealCvIndex = nextRealIndex
            currentPrivilegeIndex = nextRealIndex % privileges.count
            let indexPath = IndexPath(item: nextRealIndex, section: 0)
            cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
        }
    }

    @objc private func rightButtonPressed() {
        guard privileges.count > 0 else { return }
        
        // 计算下一个目标位置（相邻位置）
        let nextRealIndex = currentRealCvIndex + 1
        
        // 检查是否需要边界处理
        let totalItems = privileges.count * multiplier
        
        if nextRealIndex >= totalItems {
            // 如果超出右边界，跳转到左侧对应位置
            let targetIndex = 0
            currentRealCvIndex = targetIndex
            currentPrivilegeIndex = targetIndex % privileges.count
            let indexPath = IndexPath(item: targetIndex, section: 0)
            cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
        } else {
            // 正常向右切换
            currentRealCvIndex = nextRealIndex
            currentPrivilegeIndex = nextRealIndex % privileges.count
            let indexPath = IndexPath(item: nextRealIndex, section: 0)
            cv.scrollToItem(at: indexPath, at: .centeredHorizontally, animated: true)
        }
    }

    @objc private func termsOfServicePressed() {
        AppRouter.goTermsOfService()
        dismiss()
    }

    @objc private func privacyPolicyPressed() {
        AppRouter.goPrivacyPolicy()
        dismiss()
    }

    @objc private func tapBottomButton() {
        // 开始续期订阅...
        guard selectedProductIndex < vipProducts.count else { return }
        let selectedProduct = vipProducts[selectedProductIndex]
        print("选择的产品: \(selectedProduct.productId ?? "")")
        
        guard let productId = selectedProduct.productId, let payment = selectedProduct.payAmount else{
            return
        }
        
        let product = IAPProducts()
        product.productId = productId
        product.chargeAmount = payment
        
        IAPCore.shared.requestProducts([product]) {iapIds in
            if iapIds.count > 0 {
                let tradeId = String.randomNumber(length: 10)
                IAPCore.shared.addPayProductId(productId: productId, tradeId: tradeId)
            }
        }
        
        
    }
    
    // MARK: - UI
    private func setupViews() {
        bgImageView = {
            let v = AutoRatioImageView()
            v.setImage(UIImage(named: "vip_sheet_bg"))
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.top.leading.trailing.equalToSuperview()
            }
            return v
        }()
        
        closeButton = {
            let v = EPIconTertiaryButton(radius: .round, iconSize: .small, iconCode: .delete)
            v.addTarget(self, action: #selector(bgButtonPressed), for: .touchUpInside)
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.top.equalToSuperview().offset(20)
                make.size.equalTo(v.bgImageSize())
                make.trailing.equalToSuperview().offset(-16)
            }
            return v
        }()

        titleLabel = {
            let v = UILabel()
            v.font = .t.ttm
            v.textColor = .text
            v.textAlignment = .center
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(24)
                make.trailing.equalToSuperview().offset(-24)
                make.top.equalToSuperview().offset(24)
            }
            v.text = "Crushlevel VIP"
            return v
        }()

        setupPrivilegeView()

        setupAgreementsView()

        operateButton = {
            let v = StyleButton()
            v.primary(size: .large)
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(CGFloat.lrs)
                make.trailing.equalToSuperview().offset(-CGFloat.lrs)
                make.bottom.equalTo(agreenmentContainer.snp.top).offset(-16)
            }
            v.addTarget(self, action: #selector(tapBottomButton), for: .touchUpInside)
            v.setTitle("Subscribe", for: .normal)
            return v
        }()

        setupVIPSubscribeItemsView()
    }

    private func setupPrivilegeView() {
        privilegesContainer = {
            let v = UIView()
            v.cornerRadius = 12
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(CGFloat.lrs)
                make.trailing.equalToSuperview().offset(-CGFloat.lrs)
                make.top.equalToSuperview().offset(64)
                make.height.equalTo(229)
            }
            return v
        }()

        effectView = {
            let v = UIVisualEffectView(effect: UIBlurEffect(style: .light))
            v.alpha = 0.9
            privilegesContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.edges.equalToSuperview()
            }
            return v
        }()

        // cv is in privilegesContainer, cellwidth and height is same as privilegesContainer. pageEnable = true, scroll hori..
        cv = {
            layout.scrollDirection = .horizontal
            let width = UIScreen.width - 24 * 2
            layout.itemSize = CGSize(width: width, height: 229)
            layout.minimumLineSpacing = 0
            layout.minimumInteritemSpacing = 0
            layout.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)

            let v = UICollectionView(frame: CGRect.zero, collectionViewLayout: layout)
            v.backgroundColor = .clear
            v.register(VIPPrivilegeGridCell.self, forCellWithReuseIdentifier: "VIPPrivilegeGridCell")
            v.delegate = self
            v.dataSource = self
            v.isPagingEnabled = true
            v.showsHorizontalScrollIndicator = false
            privilegesContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.edges.equalToSuperview()
            }
            return v
        }()

        leftButton = {
            let v = EPIconTertiaryDarkButton(radius: .round, iconSize: .xs, iconCode: .arrowLeftBorder)
            privilegesContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.top.equalToSuperview().offset(58.5)
                make.leading.equalToSuperview().offset(16)
                make.size.equalTo(v.bgImageSize())
            }
            return v
        }()

        rightButton = {
            let v = EPIconTertiaryDarkButton(radius: .round, iconSize: .xs, iconCode: .arrowRightBorder)
            privilegesContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.top.equalToSuperview().offset(58.5)
                make.trailing.equalToSuperview().offset(-16)
                make.size.equalTo(v.bgImageSize())
            }
            return v
        }()

        leftButton.addTarget(self, action: #selector(leftButtonPressed), for: .touchUpInside)
        rightButton.addTarget(self, action: #selector(rightButtonPressed), for: .touchUpInside)
    }

    private func setupAgreementsView() {
        agreenmentContainer = {
            let v = UIView()
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.height.equalTo(32)
                make.leading.equalToSuperview()
                make.trailing.equalToSuperview()
                make.bottom.equalToSuperview().offset(-UIWindow.safeAreaBottom)
            }
            return v
        }()

        let line = {
            let v = CLLine()
            agreenmentContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.center.equalToSuperview()
                make.size.equalTo(CGSize(width: 1, height: 8))
            }
            return v
        }()

        let leftButton = {
            let v = UIButton()
            v.titleLabel?.font = UIFont.t.tls
            v.setTitleColor(.c.ctsn, for: .normal)
            agreenmentContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.trailing.equalTo(line.snp.leading).offset(-16)
                make.top.bottom.equalToSuperview()
            }
            v.addTarget(self, action: #selector(termsOfServicePressed), for: .touchUpInside)
            return v
        }()

        let rightButton = {
            let v = UIButton()
            v.titleLabel?.font = UIFont.t.tls
            v.setTitleColor(.c.ctsn, for: .normal)
            agreenmentContainer.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalTo(line.snp.trailing).offset(16)
                make.top.bottom.equalToSuperview()
            }
            v.addTarget(self, action: #selector(privacyPolicyPressed), for: .touchUpInside)
            return v
        }()

        leftButton.setTitle("Terms of Service", for: .normal)
        rightButton.setTitle("Privacy Policy", for: .normal)
    }

    private func setupVIPSubscribeItemsView() {
        tableView = {
            let v = UITableView()
            v.backgroundColor = .clear
            v.register(VIPTierListCell.self, forCellReuseIdentifier: "VIPTierListCell")
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview()
                make.trailing.equalToSuperview()
                make.top.equalTo(privilegesContainer.snp.bottom).offset(16)
                make.bottom.equalTo(operateButton.snp.top).offset(-16)
            }
            return v
        }()
        tableView.delegate = self
        tableView.dataSource = self
    }
    
}

extension VIPSubscribeSheet: UICollectionViewDelegate, UICollectionViewDataSource {
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return privileges.count * multiplier
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "VIPPrivilegeGridCell", for: indexPath) as! VIPPrivilegeGridCell
        
        let actualIndex = indexPath.item % privileges.count
        if actualIndex < privileges.count {
            let privilege = privileges[actualIndex]
            cell.configure(with: privilege)
        }
        
        return cell
    }

    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        // 更新当前索引
        let pageWidth = scrollView.frame.width
        let currentPage = Int(scrollView.contentOffset.x / pageWidth)
        currentRealCvIndex = currentPage
        currentPrivilegeIndex = currentPage % privileges.count
        
        // 实现无限循环：当接近边界时，跳转到中间位置
        let totalItems = privileges.count * multiplier
        let middleStart = (totalItems / 2) - (totalItems / 2) % privileges.count
        
        if currentPage < privileges.count {
            // 接近开始位置，跳转到中间偏后位置
            let targetIndex = middleStart + currentPrivilegeIndex
            let targetIndexPath = IndexPath(item: targetIndex, section: 0)
            DispatchQueue.main.async {
                self.cv.scrollToItem(at: targetIndexPath, at: .centeredHorizontally, animated: false)
            }
        } else if currentPage >= totalItems - privileges.count {
            // 接近结束位置，跳转到中间偏前位置
            let targetIndex = middleStart - (privileges.count - currentPrivilegeIndex)
            let targetIndexPath = IndexPath(item: targetIndex, section: 0)
            DispatchQueue.main.async {
                self.cv.scrollToItem(at: targetIndexPath, at: .centeredHorizontally, animated: false)
            }
        }
    }
}

extension VIPSubscribeSheet: UITableViewDelegate, UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return vipProducts.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "VIPTierListCell", for: indexPath) as! VIPTierListCell
        
        if indexPath.row < vipProducts.count {
            let product = vipProducts[indexPath.row]
            cell.configure(with: product)
            cell.setupSelected(selected: indexPath.row == selectedProductIndex)
        }
        
        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        print("didSelectRowAt \(indexPath)")
        selectedProductIndex = indexPath.row
        tableView.reloadData()
    }
}

class VIPPrivilegeGridCell: UICollectionViewCell {
    var icon: UIImageView!
    var titleLabel: CLLabel!
    var descLabel: LineSpaceLabel!

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupViews()
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private func setupViews() {
        backgroundColor = .clear
        icon = {
            let v = UIImageView()
            v.cornerRadius = 8
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.size.equalTo(CGSize(width: 140, height: 93))
                make.top.equalToSuperview().offset(24)
                make.centerX.equalToSuperview()
            }
            return v
        }()

        titleLabel = {
            let v = CLLabel()
            v.font = .t.tts
            v.textAlignment = .center
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(16)
                make.trailing.equalToSuperview().offset(-16)
                make.top.equalTo(icon.snp.bottom).offset(16)
            }
            return v
        }()

        descLabel = {
            let v = LineSpaceLabel()
            let typo = CLSystemToken.typography(token: .tls)
            v.textColor = .text
            v.textAlignment = .center
            v.config(typo)
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(16)
                make.trailing.equalToSuperview().offset(-16)
                make.top.equalTo(titleLabel.snp.bottom).offset(8)
            }
            return v
        }()
    }
    
    func configure(with privilege: MemberPrivDict) {
        titleLabel.text = privilege.title ?? ""
        descLabel.text = privilege.desc ?? ""
        
        // 设置图片
        if let imgUrl = privilege.img, !imgUrl.isEmpty {
            // 使用网络图片加载
            icon.loadImage(imgUrl, bgColor: .clear)
        } else {
            
        }
    }
}

class VIPTierListCell: UITableViewCell {
    var blockView: UIView!
    var checkButton: EPRadioButton!
    var coinAndLabel: CLIconLabel!

    var periodLabel: CLLabel!
    var descLabel: CLLabel!

    var gradientFlag: GradientView!
    var discountLabelOnFlag: CLLabel!

    override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)

        selectionStyle = .none
        backgroundColor = .clear

        setupViews()
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private func setupViews() {
        blockView = {
            let v = UIView()
            v.backgroundColor = .c.csnn
            v.cornerRadius = 12
            v.layer.borderWidth = 0
            v.layer.borderColor = UIColor.c.cpn.cgColor
            contentView.addSubview(v)
            v.snp.makeConstraints { make in
                make.leading.equalToSuperview().offset(CGFloat.lrs)
                make.trailing.equalToSuperview().offset(-CGFloat.lrs)
                make.top.equalToSuperview()
                make.bottom.equalToSuperview().offset(-12)
                make.height.equalTo(80)
            }
            return v
        }()

        checkButton = {
            let v = EPRadioButton()
            v.setupRadioStyle(.checkEmpty)
            v.isUserInteractionEnabled = false
            blockView.addSubview(v)
            v.snp.makeConstraints { make in
                make.trailing.equalToSuperview().offset(-24)
                make.centerY.equalToSuperview()
            }
            return v
        }()

        coinAndLabel = {
            let v = CLIconLabel()
            v.iconSize = CGSize(width: 16, height: 16)
            //v.iconImageView.image = UIImage(named: "icon_16_diamond")
            v.iconImageView.isHidden = true
            v.contentLabel.textColor = .text
            v.contentLabel.font = .t.tnmm
            blockView.addSubview(v)
            v.snp.makeConstraints { make in
                make.centerY.equalToSuperview()
                make.trailing.equalTo(checkButton.snp.leading).offset(-8)
            }
            return v
        }()

        periodLabel = {
            let v = CLLabel()
            v.font = .t.tts
            v.textColor = .text
            blockView.addSubview(v)
            v.snp.makeConstraints { make in
                make.centerY.equalToSuperview()
                make.leading.equalToSuperview().offset(24)
            }
            return v
        }()

        descLabel = {
            let v = CLLabel()
            v.font = .t.tls
            v.textColor = .c.ctsn
            blockView.addSubview(v)
            v.snp.makeConstraints { make in
                make.lastBaseline.equalTo(periodLabel)
                make.leading.equalTo(periodLabel.snp.trailing).offset(4)
            }
            return v
        }()

        gradientFlag = {
            let gradient = CLSystemToken.gradient(token: .ccvn)
            let v = GradientView(colors: gradient.colors(), gradientType: .leftToRight)
            v.cornerRadius = 12
            v.backgroundColor = .c.csnn
            v.layer.maskedCorners = [.layerMinXMinYCorner, .layerMaxXMaxYCorner]
            blockView.addSubview(v)
            v.snp.makeConstraints { make in
                make.height.equalTo(24)
                make.leading.top.equalToSuperview()
            }
            return v
        }()

        discountLabelOnFlag = {
            let v = CLLabel()
            v.font = .t.tbss
            v.textColor = .c.cbd
            gradientFlag.addSubview(v)
            v.snp.makeConstraints { make in
                make.centerY.equalToSuperview()
                make.leading.equalToSuperview().offset(8)
                make.trailing.equalToSuperview().offset(-8)
            }
            return v
        }()
    }
    
    func configure(with product: VIPSubcribeProduct) {
        // 设置价格
//        if let chargeAmount = product.chargeAmount {
//            let coin = Coin(cents: chargeAmount)
//            coinAndLabel.contentLabel.text = coin.formatted
//        }
        
        let period = product.period ?? .month
        
        // 设置周期
        let periodText = getPeriodText(from: product.period)
        periodLabel.text = periodText
        
        // 设置描述价格
        if let payAmount = product.payAmount {
            let price = Coin(cents: payAmount)
            
            if period == .month{
                descLabel.isHidden = true
            }else if period == .season{
                descLabel.isHidden = false
                let pricePerMonth = CGFloat(payAmount) / 3.0
                let pricePerMonthCoin = Coin(cents: Int(pricePerMonth))
                descLabel.text = "$\(pricePerMonthCoin.formatted)/\(getPeriodShortText(from: product.period))"
            }else if period == .year{
                descLabel.isHidden = false
                let pricePerMonth = CGFloat(payAmount) / 12.0
                let pricePerMonthCoin = Coin(cents: Int(pricePerMonth))
                descLabel.text = "$\(pricePerMonthCoin.formatted)/\(getPeriodShortText(from: product.period))"
            }
            // CrushCoin
            coinAndLabel.contentLabel.text = "$\(price.formatted)"
        }
        
        // 设置折扣标签
        if let discount = product.discount, let discountFloat = Float(discount), discountFloat > 0 {
            gradientFlag.isHidden = false
            discountLabelOnFlag.text = "\(discount)% Off"
        } else {
            gradientFlag.isHidden = true
        }
    }
    
    private func getPeriodText(from period: PriceType?) -> String {
        switch period {
        case .month:
            return "1 Month"
        case .season:
            return "3 Months"
        case .year:
            return "1 Year"
        case .none:
            return "1 Month"
        }
    }
    
    private func getPeriodShortText(from period: PriceType?) -> String {
        switch period {
        case .month:
            return "Month"
        case .season:
            return "Months"
        case .year:
            return "Year"
        case .none:
            return "Month"
        }
    }

    func setupSelected(selected: Bool) {
        checkButton.isSelected = selected
        blockView.layer.borderWidth = selected ? 2 : 0
    }
}