//
//  RealNameAuthViewController.swift
//  suixinkan
//

import PhotosUI
import SnapKit
import UIKit

/// 实名认证页面，展示审核状态并允许提交基础实名资料。
final class RealNameAuthViewController: UIViewController {

    private let viewModel = RealNameAuthViewModel()

    private let scrollView = UIScrollView()
    private let contentStack = UIStackView()

    private let realNameField = UITextField()
    private let idCardField = UITextField()
    private let smsCodeField = UITextField()
    private let frontImageView = UIImageView()
    private let backImageView = UIImageView()
    private let statusLabel = UILabel()
    private let longValidSwitch = UISwitch()
    private let startDatePicker = UIDatePicker()
    private let endDatePicker = UIDatePicker()

    /// 视图加载完成后的 UI 初始化与数据绑定。
    override func viewDidLoad() {
        super.viewDidLoad()
        title = "实名认证"
        view.backgroundColor = AppDesignUIKit.pageBackground
        setupForm()
        viewModel.onChange = { [weak self] in self?.applyViewModel() }
        Task { await loadInfo() }
    }

    /// 初始化Form相关 UI 或状态。
    private func setupForm() {
        contentStack.axis = .vertical
        contentStack.spacing = 16
        view.addSubview(scrollView)
        scrollView.addSubview(contentStack)
        scrollView.snp.makeConstraints { make in make.edges.equalToSuperview() }
        contentStack.snp.makeConstraints { make in
            make.edges.equalToSuperview().inset(16)
            make.width.equalTo(scrollView).offset(-32)
        }

        [realNameField, idCardField, smsCodeField].forEach {
            $0.borderStyle = .roundedRect
            $0.font = .systemFont(ofSize: 16)
        }
        realNameField.placeholder = "请输入姓名"
        idCardField.placeholder = "请输入身份证号码"
        smsCodeField.placeholder = "请输入短信验证码"
        smsCodeField.keyboardType = .numberPad

        [frontImageView, backImageView].forEach {
            $0.backgroundColor = UIColor(hex: 0xF8FAFC)
            $0.contentMode = .scaleAspectFit
            $0.layer.cornerRadius = 8
            $0.clipsToBounds = true
            $0.isUserInteractionEnabled = true
            $0.snp.makeConstraints { make in make.height.equalTo(160) }
        }
        frontImageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(pickFront)))
        backImageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(pickBack)))

        startDatePicker.datePickerMode = .date
        endDatePicker.datePickerMode = .date
        if #available(iOS 17.0, *) {
            startDatePicker.preferredDatePickerStyle = .compact
            endDatePicker.preferredDatePickerStyle = .compact
        }

        let sendCodeButton = UIButton(type: .system)
        sendCodeButton.setTitle("获取验证码", for: .normal)
        sendCodeButton.addTarget(self, action: #selector(sendCodeTapped), for: .touchUpInside)

        let submitButton = makePrimaryButton(title: "下一步")
        submitButton.addTarget(self, action: #selector(submitTapped), for: .touchUpInside)

        statusLabel.numberOfLines = 0
        statusLabel.font = .systemFont(ofSize: 13)
        statusLabel.textColor = AppDesignUIKit.textSecondary

        contentStack.addArrangedSubview(makeSectionTitle("审核状态"))
        contentStack.addArrangedSubview(statusLabel)
        contentStack.addArrangedSubview(makeSectionTitle("身份证国徽面"))
        contentStack.addArrangedSubview(backImageView)
        contentStack.addArrangedSubview(makeSectionTitle("身份证人像面"))
        contentStack.addArrangedSubview(frontImageView)
        contentStack.addArrangedSubview(labeledField("姓名", realNameField))
        contentStack.addArrangedSubview(labeledField("身份证号码", idCardField))

        let longValidRow = UIStackView(arrangedSubviews: [UILabel(text: "长期有效"), longValidSwitch])
        longValidRow.axis = .horizontal
        longValidSwitch.addTarget(self, action: #selector(longValidChanged), for: .valueChanged)
        contentStack.addArrangedSubview(longValidRow)
        contentStack.addArrangedSubview(startDatePicker)
        contentStack.addArrangedSubview(endDatePicker)

        let smsRow = UIStackView(arrangedSubviews: [smsCodeField, sendCodeButton])
        smsRow.axis = .horizontal
        smsRow.spacing = 8
        smsCodeField.snp.makeConstraints { make in make.height.equalTo(44) }
        contentStack.addArrangedSubview(smsRow)
        contentStack.addArrangedSubview(submitButton)
    }

    /// 创建SectionTitle实例。
    private func makeSectionTitle(_ text: String) -> UILabel {
        let label = UILabel()
        label.text = text
        label.font = .systemFont(ofSize: 17, weight: .semibold)
        return label
    }

    /// labeled字段相关逻辑。
    private func labeledField(_ title: String, _ field: UITextField) -> UIStackView {
        let label = UILabel()
        label.text = title
        label.font = .systemFont(ofSize: 15, weight: .medium)
        let stack = UIStackView(arrangedSubviews: [label, field])
        stack.axis = .vertical
        stack.spacing = 8
        field.snp.makeConstraints { make in make.height.equalTo(44) }
        return stack
    }

    /// apply视图模型相关逻辑。
    private func applyViewModel() {
        realNameField.text = viewModel.realName
        idCardField.text = viewModel.idCardNo
        smsCodeField.text = viewModel.smsCode
        longValidSwitch.isOn = viewModel.isLongValid
        startDatePicker.date = viewModel.startDate
        endDatePicker.date = viewModel.endDate
        endDatePicker.isEnabled = !viewModel.isLongValid

        if let data = viewModel.pendingFrontImageData, let image = UIImage(data: data) {
            frontImageView.image = image
        } else if !viewModel.frontUrl.isEmpty {
            frontImageView.loadRemoteImage(urlString: viewModel.frontUrl, contentMode: .scaleAspectFit)
        }

        if let data = viewModel.pendingBackImageData, let image = UIImage(data: data) {
            backImageView.image = image
        } else if !viewModel.backUrl.isEmpty {
            backImageView.image = nil
            backImageView.loadRemoteImage(urlString: viewModel.backUrl, contentMode: .scaleAspectFit)
        }

        if let info = viewModel.info {
            statusLabel.text = """
            审核状态：\(viewModel.auditStatusText(info.auditStatus))
            审核人：\(info.auditor?.name ?? "--")
            审核时间：\(info.auditAt ?? "--")
            审核备注：\(info.rejectReason ?? "--")
            """
        } else {
            statusLabel.text = "尚未提交实名认证"
        }

        if let message = viewModel.statusMessage {
            showToast(message)
        }
    }

    /// 加载Info数据。
    private func loadInfo() async {
        do {
            try await appServices.globalLoading.withLoading(message: "加载中...") {
                try await self.viewModel.load(api: self.appServices.profileAPI)
            }
        } catch {
            showToast(error.localizedDescription)
        }
    }

    /// longValid变更相关逻辑。
    @objc private func longValidChanged() {
        viewModel.isLongValid = longValidSwitch.isOn
    }

    /// 点击send验证码的处理逻辑。
    @objc private func sendCodeTapped() {
        Task {
            do {
                try await viewModel.sendCode(api: appServices.profileAPI)
            } catch {
                showToast(error.localizedDescription)
            }
        }
    }

    /// 提交Tapped。
    @objc private func submitTapped() {
        viewModel.realName = realNameField.text ?? ""
        viewModel.idCardNo = idCardField.text ?? ""
        viewModel.smsCode = smsCodeField.text ?? ""
        viewModel.startDate = startDatePicker.date
        viewModel.endDate = endDatePicker.date

        guard let scenicId = appServices.accountContext.currentScenic?.id else {
            showToast("请先选择景区")
            return
        }
        Task {
            do {
                try await appServices.globalLoading.withLoading(message: "提交中...") {
                    try await self.viewModel.submit(
                        api: self.appServices.profileAPI,
                        uploader: self.appServices.ossUploadService,
                        scenicId: scenicId
                    )
                }
            } catch {
                showToast(error.localizedDescription)
            }
        }
    }

    private var pendingSide: RealNameImageSide = .front

    /// pickFront相关逻辑。
    @objc private func pickFront() {
        pendingSide = .front
        presentImagePicker()
    }

    /// pickBack相关逻辑。
    @objc private func pickBack() {
        pendingSide = .back
        presentImagePicker()
    }

    /// 弹出ImagePicker页面。
    private func presentImagePicker() {
        var config = PHPickerConfiguration()
        config.filter = .images
        config.selectionLimit = 1
        let picker = PHPickerViewController(configuration: config)
        picker.delegate = self
        present(picker, animated: true)
    }
}

extension RealNameAuthViewController: PHPickerViewControllerDelegate {
    /// picker 业务逻辑。
    func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
        picker.dismiss(animated: true)
        guard let provider = results.first?.itemProvider, provider.canLoadObject(ofClass: UIImage.self) else { return }
        provider.loadObject(ofClass: UIImage.self) { [weak self] object, _ in
            guard let self, let image = object as? UIImage, let data = image.jpegData(compressionQuality: 0.9) else { return }
            DispatchQueue.main.async {
                do {
                    try self.viewModel.prepareIdentityImage(data: data, side: self.pendingSide)
                } catch {
                    self.showToast(error.localizedDescription)
                }
            }
        }
    }
}

private extension UILabel {
    /// 初始化实例。
    convenience init(text: String) {
        self.init()
        self.text = text
        self.font = .systemFont(ofSize: 16, weight: .semibold)
    }
}