//
//  EPLoginViewController.swift
//  YuMi
//
//  Created by AI on 2025-01-27.
//

import UIKit

@objc class EPLoginViewController: UIViewController {
    
    // MARK: - Properties
    
    private let backgroundImageView = UIImageView()
    private let logoImageView = UIImageView()
    private let epartiTitleLabel = UILabel()
    
    private let idLoginButton = EPLoginButton()
    private let emailLoginButton = EPLoginButton()
    
    private let agreeCheckbox = UIButton(type: .custom)
    private let policyLabel = EPPolicyLabel()
    
    private let feedbackButton = UIButton(type: .custom)
    
    #if DEBUG
    private let debugButton = UIButton(type: .custom)
    #endif
    
    private let policySelectedKey = EPLoginConfig.Keys.policyAgreed
    
    // MARK: - Lifecycle
    
    override func viewDidLoad() {
        super.viewDidLoad()
        navigationController?.setNavigationBarHidden(true, animated: false)
        setupUI()
        loadPolicyStatus()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
    }
    
    // MARK: - Setup
    
    private func setupUI() {
        setupBackground()
        setupLogo()
        setupLoginButtons()
        setupPolicyArea()
        setupNavigationBar()
    }
    
    private func setupBackground() {
        view.addSubview(backgroundImageView)
        backgroundImageView.image = kImage(EPLoginConfig.Images.background)
        backgroundImageView.contentMode = .scaleAspectFill
        
        backgroundImageView.snp.makeConstraints { make in
            make.edges.equalToSuperview()
        }
    }
    
    private func setupLogo() {
        view.addSubview(logoImageView)
        logoImageView.image = kImage(EPLoginConfig.Images.loginBg)
        
        logoImageView.snp.makeConstraints { make in
            make.top.leading.trailing.equalTo(view)
            make.height.equalTo(EPLoginConfig.Layout.logoHeight)
        }
        
        // E-PARTI 标题
        view.addSubview(epartiTitleLabel)
        epartiTitleLabel.text = "E-PARTI"
        epartiTitleLabel.font = .systemFont(ofSize: EPLoginConfig.Layout.epartiTitleFontSize, weight: .bold)
        epartiTitleLabel.textColor = EPLoginConfig.Colors.textLight
        epartiTitleLabel.transform = CGAffineTransform(a: 1, b: 0, c: -0.2, d: 1, tx: 0, ty: 0) // 斜体效果
        
        epartiTitleLabel.snp.makeConstraints { make in
            make.leading.equalToSuperview().offset(EPLoginConfig.Layout.epartiTitleLeading)
            make.bottom.equalTo(logoImageView.snp.bottom).offset(EPLoginConfig.Layout.epartiTitleBottomOffset)
        }
    }
    
    private func setupLoginButtons() {
        // 配置按钮
        idLoginButton.configure(
            icon: EPLoginConfig.Images.iconLoginId,
            title: YMLocalizedString(EPLoginConfig.LocalizedKeys.idLogin)
        )
        idLoginButton.delegate = self
        
        emailLoginButton.configure(
            icon: EPLoginConfig.Images.iconLoginEmail,
            title: YMLocalizedString(EPLoginConfig.LocalizedKeys.emailLogin)
        )
        emailLoginButton.delegate = self
        
        // StackView 布局
        let stackView = UIStackView(arrangedSubviews: [idLoginButton, emailLoginButton])
        stackView.axis = .vertical
        stackView.spacing = EPLoginConfig.Layout.loginButtonSpacing
        stackView.distribution = .fillEqually
        view.addSubview(stackView)
        
        stackView.snp.makeConstraints { make in
            make.leading.equalToSuperview().offset(EPLoginConfig.Layout.loginButtonHorizontalPadding)
            make.trailing.equalToSuperview().offset(-EPLoginConfig.Layout.loginButtonHorizontalPadding)
            make.top.equalTo(logoImageView.snp.bottom)
        }
        
        idLoginButton.snp.makeConstraints { make in
            make.height.equalTo(EPLoginConfig.Layout.loginButtonHeight)
        }
        
        emailLoginButton.snp.makeConstraints { make in
            make.height.equalTo(EPLoginConfig.Layout.loginButtonHeight)
        }
    }
    
    private func setupPolicyArea() {
        view.addSubview(agreeCheckbox)
        view.addSubview(policyLabel)
        
        agreeCheckbox.setImage(kImage("login_privace_select"), for: .selected)
        agreeCheckbox.setImage(kImage("login_privace_unselect"), for: .normal)
        agreeCheckbox.addTarget(self, action: #selector(togglePolicyCheckbox), for: .touchUpInside)
        
        policyLabel.onUserAgreementTapped = { [weak self] in
            self?.openPolicy(url: "https://example.com/user-agreement")
        }
        policyLabel.onPrivacyPolicyTapped = { [weak self] in
            self?.openPolicy(url: "https://example.com/privacy-policy")
        }
        
        agreeCheckbox.snp.makeConstraints { make in
            make.leading.equalToSuperview().offset(EPLoginConfig.Layout.horizontalPadding)
            make.bottom.equalTo(view.safeAreaLayoutGuide).offset(-30)
            make.size.equalTo(EPLoginConfig.Layout.checkboxSize)
        }
        
        policyLabel.snp.makeConstraints { make in
            make.leading.equalTo(agreeCheckbox.snp.trailing).offset(8)
            make.trailing.equalToSuperview().offset(-EPLoginConfig.Layout.horizontalPadding)
            make.centerY.equalTo(agreeCheckbox)
        }
    }
    
    private func setupNavigationBar() {
        view.addSubview(feedbackButton)
        feedbackButton.setTitle(YMLocalizedString(EPLoginConfig.LocalizedKeys.feedback), for: .normal)
        feedbackButton.titleLabel?.font = .systemFont(ofSize: EPLoginConfig.Layout.smallFontSize)
        feedbackButton.backgroundColor = EPLoginConfig.Colors.backgroundTransparent
        feedbackButton.layer.cornerRadius = EPLoginConfig.Layout.feedbackButtonCornerRadius
        feedbackButton.addTarget(self, action: #selector(handleFeedback), for: .touchUpInside)
        
        feedbackButton.snp.makeConstraints { make in
            make.trailing.equalToSuperview().offset(-EPLoginConfig.Layout.compactHorizontalPadding)
            make.top.equalTo(view.safeAreaLayoutGuide).offset(8)
            make.height.equalTo(EPLoginConfig.Layout.feedbackButtonHeight)
        }
        
        #if DEBUG
        view.addSubview(debugButton)
        debugButton.setTitle("切换环境", for: .normal)
        debugButton.setTitleColor(.blue, for: .normal)
        debugButton.addTarget(self, action: #selector(handleDebug), for: .touchUpInside)
        
        debugButton.snp.makeConstraints { make in
            make.leading.equalToSuperview().offset(EPLoginConfig.Layout.compactHorizontalPadding)
            make.top.equalTo(view.safeAreaLayoutGuide).offset(8)
        }
        #endif
    }
    
    // MARK: - Actions
    
    private func handleIDLogin() {
        let vc = EPLoginTypesViewController()
        vc.displayType = .id
        navigationController?.pushViewController(vc, animated: true)
    }
    
    private func handleEmailLogin() {
        let vc = EPLoginTypesViewController()
        vc.displayType = .email
        navigationController?.pushViewController(vc, animated: true)
    }
    
    @objc private func togglePolicyCheckbox() {
        agreeCheckbox.isSelected.toggle()
        UserDefaults.standard.set(agreeCheckbox.isSelected, forKey: policySelectedKey)
    }
    
    @objc private func handleFeedback() {
        print("[EPLogin] Feedback - 占位，Phase 2 实现")
    }
    
    #if DEBUG
    @objc private func handleDebug() {
        print("[EPLogin] Debug - 占位，Phase 2 实现")
    }
    #endif
    
    private func openPolicy(url: String) {
        let webVC = XPWebViewController(roomUID: nil)
        webVC.url = url
        navigationController?.pushViewController(webVC, animated: true)
    }
    
    // MARK: - Helpers
    
    private func loadPolicyStatus() {
        agreeCheckbox.isSelected = UserDefaults.standard.bool(forKey: policySelectedKey)
        // 默认勾选
        if !UserDefaults.standard.bool(forKey: EPLoginConfig.Keys.hasLaunchedBefore) {
            agreeCheckbox.isSelected = true
            UserDefaults.standard.set(true, forKey: policySelectedKey)
            UserDefaults.standard.set(true, forKey: EPLoginConfig.Keys.hasLaunchedBefore)
        }
    }
    
    private func checkPolicyAgreed() -> Bool {
        if !agreeCheckbox.isSelected {
            // Phase 2: 显示提示
            print("[EPLogin] Please agree to policy first")
            return false
        }
        return true
    }
}

// MARK: - EPLoginButtonDelegate

extension EPLoginViewController: EPLoginButtonDelegate {
    func loginButtonDidTap(_ button: EPLoginButton) {
        guard checkPolicyAgreed() else { return }
        
        if button == idLoginButton {
            handleIDLogin()
        } else if button == emailLoginButton {
            handleEmailLogin()
        }
    }
}