//
//  SettingViewController.swift
//  suixinkan
//

import SnapKit
import UIKit

/// 设置中心页面，对齐 Android `SettingScreen` 的当前可见设置项。
final class SettingViewController: BaseViewController {
    private let viewModel: SettingViewModel
    private let settingAPI: SettingAPI

    private let contentView = UIView()
    private let cardView = UIView()
    private let rowsStack = UIStackView()
    private let versionRow = SettingMenuRow(title: "系统版本", showsChevron: false)
    private let copyrightLabel = UILabel()

    init(
        viewModel: SettingViewModel = SettingViewModel(),
        settingAPI: SettingAPI = NetworkServices.shared.settingAPI
    ) {
        self.viewModel = viewModel
        self.settingAPI = settingAPI
        super.init(nibName: nil, bundle: nil)
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func setupNavigationBar() {
        title = "设置"
    }

    override func setupUI() {
        view.backgroundColor = AppColor.pageBackground

        view.addSubview(contentView)
        contentView.addSubview(cardView)
        cardView.addSubview(rowsStack)
        contentView.addSubview(copyrightLabel)

        cardView.backgroundColor = .white
        cardView.layer.cornerRadius = 12
        cardView.clipsToBounds = true

        rowsStack.axis = .vertical

        copyrightLabel.text = "Copyright © 2025 All Rights Reserved\n苏ICP备2025157647号"
        copyrightLabel.font = .systemFont(ofSize: 14)
        copyrightLabel.textColor = UIColor(hex: 0xB6BECA)
        copyrightLabel.textAlignment = .center
        copyrightLabel.numberOfLines = 0

        let rows: [SettingMenuRow] = [
            SettingMenuRow(title: "关于我们"),
            versionRow,
            SettingMenuRow(title: "App下载", value: "复制链接", valueColor: AppColor.primary, showsChevron: false),
            SettingMenuRow(title: "用户协议"),
            SettingMenuRow(title: "隐私政策", showsDivider: false),
        ]
        rows.forEach(rowsStack.addArrangedSubview)

        rows[0].addTarget(self, action: #selector(aboutTapped), for: .touchUpInside)
        rows[2].addTarget(self, action: #selector(copyDownloadTapped), for: .touchUpInside)
        rows[3].addTarget(self, action: #selector(userAgreementTapped), for: .touchUpInside)
        rows[4].addTarget(self, action: #selector(privacyTapped), for: .touchUpInside)
    }

    override func setupConstraints() {
        contentView.snp.makeConstraints { make in
            make.edges.equalTo(view.safeAreaLayoutGuide).inset(16)
        }
        cardView.snp.makeConstraints { make in
            make.top.leading.trailing.equalToSuperview()
        }
        rowsStack.snp.makeConstraints { make in
            make.edges.equalToSuperview().inset(UIEdgeInsets(top: 0, left: 16, bottom: 0, right: 16))
        }
        copyrightLabel.snp.makeConstraints { make in
            make.leading.trailing.equalToSuperview()
            make.bottom.equalToSuperview().offset(-16)
        }
    }

    override func bindActions() {
        viewModel.onStateChange = { [weak self] in
            Task { @MainActor in self?.applyViewModel() }
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        applyViewModel()
        Task { await viewModel.checkLatestVersion(api: settingAPI) }
    }

    private func applyViewModel() {
        versionRow.configure(value: viewModel.appVersion, showsUpgrade: viewModel.hasNewVersion)
    }

    @objc private func aboutTapped() {
        openAgreement(.aboutUs)
    }

    @objc private func copyDownloadTapped() {
        UIPasteboard.general.string = viewModel.appDownloadURL.absoluteString
        showToast("已复制到剪贴板!")
    }

    @objc private func userAgreementTapped() {
        openAgreement(.userAgreement)
    }

    @objc private func privacyTapped() {
        openAgreement(.privacyPolicy)
    }

    private func openAgreement(_ kind: SettingAgreementKind) {
        let destination = viewModel.agreementDestination(for: kind)
        navigationController?.pushViewController(
            AgreementWebViewController(title: destination.title, url: destination.url),
            animated: true
        )
    }
}

/// 设置中心菜单行，展示标题、右侧文本、更新标记和箭头。
final class SettingMenuRow: UIControl {
    private let titleLabel = UILabel()
    private let rightStack = UIStackView()
    private let valueLabel = UILabel()
    private let upgradeImageView = UIImageView()
    private let chevronImageView = UIImageView()
    private let divider = UIView()
    private let showsChevron: Bool

    init(
        title: String,
        value: String? = nil,
        valueColor: UIColor = AppColor.textPrimary,
        showsChevron: Bool = true,
        showsDivider: Bool = true
    ) {
        self.showsChevron = showsChevron
        super.init(frame: .zero)
        setupUI()
        setupConstraints()
        titleLabel.text = title
        valueLabel.text = value
        valueLabel.textColor = valueColor
        chevronImageView.isHidden = !showsChevron
        divider.isHidden = !showsDivider
        accessibilityTraits.insert(.button)
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override var isHighlighted: Bool {
        didSet {
            backgroundColor = isHighlighted ? UIColor.black.withAlphaComponent(0.04) : .clear
        }
    }

    func configure(value: String?, showsUpgrade: Bool) {
        valueLabel.text = value
        upgradeImageView.isHidden = !showsUpgrade
    }

    private func setupUI() {
        titleLabel.font = .systemFont(ofSize: 14)
        titleLabel.textColor = UIColor(hex: 0x4B5563)

        valueLabel.font = .systemFont(ofSize: 14)
        valueLabel.textColor = AppColor.textPrimary

        upgradeImageView.image = UIImage(systemName: "arrow.up.circle")?.withRenderingMode(.alwaysTemplate)
        upgradeImageView.tintColor = UIColor(hex: 0x1F1F1F)
        upgradeImageView.contentMode = .scaleAspectFit
        upgradeImageView.isHidden = true

        chevronImageView.image = UIImage(systemName: "chevron.right")?.withRenderingMode(.alwaysTemplate)
        chevronImageView.tintColor = AppColor.textTertiary
        chevronImageView.contentMode = .scaleAspectFit

        divider.backgroundColor = AppColor.border

        rightStack.axis = .horizontal
        rightStack.alignment = .center
        rightStack.spacing = 4
        [valueLabel, upgradeImageView, chevronImageView].forEach(rightStack.addArrangedSubview)

        [titleLabel, rightStack, divider].forEach(addSubview)
    }

    private func setupConstraints() {
        snp.makeConstraints { make in
            make.height.equalTo(52)
        }

        titleLabel.snp.makeConstraints { make in
            make.leading.centerY.equalToSuperview()
        }

        upgradeImageView.snp.makeConstraints { make in
            make.width.height.equalTo(24)
        }

        chevronImageView.snp.makeConstraints { make in
            make.width.height.equalTo(24)
        }

        rightStack.snp.makeConstraints { make in
            make.centerY.equalToSuperview()
            make.trailing.equalToSuperview()
            make.leading.greaterThanOrEqualTo(titleLabel.snp.trailing).offset(12)
        }

        divider.snp.makeConstraints { make in
            make.leading.trailing.bottom.equalToSuperview()
            make.height.equalTo(0.5)
        }
    }
}