// TermsViewController.swift
// Emoney Info

import UIKit

final class TermsViewController: UIViewController {

    // MARK: - Lifecycle

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = Theme.Color.background
        setupUI()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        navigationController?.setNavigationBarHidden(true, animated: animated)
        (tabBarController as? MainTabBarController)?.setTabBarHidden(true, animated: animated)
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        (tabBarController as? MainTabBarController)?.setTabBarHidden(false, animated: animated)
    }

    // MARK: - Setup

    private func setupUI() {
        let scrollView  = UIScrollView()
        let contentView = UIView()
        scrollView.showsVerticalScrollIndicator = false
        scrollView.translatesAutoresizingMaskIntoConstraints = false
        contentView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(scrollView)
        scrollView.addSubview(contentView)

        NSLayoutConstraint.activate([
            scrollView.topAnchor.constraint(equalTo: view.topAnchor),
            scrollView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            scrollView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
            contentView.topAnchor.constraint(equalTo: scrollView.topAnchor),
            contentView.leadingAnchor.constraint(equalTo: scrollView.leadingAnchor),
            contentView.trailingAnchor.constraint(equalTo: scrollView.trailingAnchor),
            contentView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor),
            contentView.widthAnchor.constraint(equalTo: scrollView.widthAnchor),
        ])

        // MARK: Back + nav label
        let backButton = UIButton(type: .system)
        let chevron = UIImage(systemName: "chevron.left",
                              withConfiguration: UIImage.SymbolConfiguration(pointSize: 16, weight: .semibold))
        backButton.setImage(chevron, for: .normal)
        backButton.tintColor = Theme.Color.textPrimary
        backButton.addTarget(self, action: #selector(backTapped), for: .touchUpInside)
        backButton.translatesAutoresizingMaskIntoConstraints = false

        let navLabel = UILabel()
        navLabel.text = L10n.aboutTerms
        navLabel.font = Theme.Font.caption(weight: .semibold)
        navLabel.textColor = Theme.Color.textSecondary
        navLabel.translatesAutoresizingMaskIntoConstraints = false

        // MARK: Last updated chip
        let updatedLabel = makePaddedLabel(text: L10n.termsLastUpdated,
                                           color: Theme.Color.secondary,
                                           bg: Theme.Color.primary.withAlphaComponent(0.15))

        // MARK: Hero title (mixed weight)
        let heroLabel = UILabel()
        let heroAttr = NSMutableAttributedString(
            string: L10n.termsTitleRegular + " ",
            attributes: [
                .font: UIFont.systemFont(ofSize: 32, weight: .regular),
                .foregroundColor: Theme.Color.textPrimary,
            ]
        )
        heroAttr.append(NSAttributedString(
            string: L10n.termsTitleBold,
            attributes: [
                .font: UIFont.systemFont(ofSize: 32, weight: .bold),
                .foregroundColor: Theme.Color.textPrimary,
            ]
        ))
        heroLabel.attributedText = heroAttr
        heroLabel.numberOfLines  = 0
        heroLabel.translatesAutoresizingMaskIntoConstraints = false

        // MARK: Subtitle
        let subtitleLabel = UILabel()
        subtitleLabel.text = L10n.termsSubtitle
        subtitleLabel.font = Theme.Font.body(weight: .regular)
        subtitleLabel.textColor = Theme.Color.textSecondary
        subtitleLabel.numberOfLines = 0
        subtitleLabel.translatesAutoresizingMaskIntoConstraints = false

        // MARK: Terms sections
        let termsStack = UIStackView()
        termsStack.axis    = .vertical
        termsStack.spacing = 16
        termsStack.translatesAutoresizingMaskIntoConstraints = false

        for (index, section) in TermsData.sections.enumerated() {
            let row = makeSectionRow(number: index + 1, section: section)
            termsStack.addArrangedSubview(row)
        }

        // MARK: Contact card (teal)
        let contactCard = UIView()
        contactCard.backgroundColor   = Theme.Color.primary
        contactCard.layer.cornerRadius = 20
        contactCard.translatesAutoresizingMaskIntoConstraints = false

        let contactTitle = UILabel()
        contactTitle.text = L10n.termsContactTitle
        contactTitle.font = Theme.Font.subtitle(weight: .bold)
        contactTitle.textColor = .white
        contactTitle.numberOfLines = 0
        contactTitle.translatesAutoresizingMaskIntoConstraints = false

        let contactDesc = UILabel()
        contactDesc.text = L10n.termsContactDesc
        contactDesc.font = Theme.Font.caption(weight: .regular)
        contactDesc.textColor = UIColor.white.withAlphaComponent(0.85)
        contactDesc.numberOfLines = 0
        contactDesc.translatesAutoresizingMaskIntoConstraints = false

        let contactButton = UIButton(type: .system)
        contactButton.setTitle(L10n.termsContactButton, for: .normal)
        contactButton.titleLabel?.font = Theme.Font.body(weight: .semibold)
        contactButton.setTitleColor(Theme.Color.primary, for: .normal)
        contactButton.backgroundColor = .white
        contactButton.layer.cornerRadius = 14
        contactButton.contentEdgeInsets = UIEdgeInsets(top: 12, left: 28, bottom: 12, right: 28)
        contactButton.addTarget(self, action: #selector(contactTapped), for: .touchUpInside)
        contactButton.translatesAutoresizingMaskIntoConstraints = false

        [contactTitle, contactDesc, contactButton].forEach { contactCard.addSubview($0) }

        // MARK: Footer
        let footerLabel = UILabel()
        footerLabel.text = L10n.footerCopyright
        footerLabel.font = Theme.Font.caption(weight: .regular)
        footerLabel.textColor = Theme.Color.textSecondary
        footerLabel.textAlignment = .center
        footerLabel.translatesAutoresizingMaskIntoConstraints = false

        [backButton, navLabel, updatedLabel, heroLabel, subtitleLabel,
         termsStack, contactCard, footerLabel].forEach { contentView.addSubview($0) }

        NSLayoutConstraint.activate([
            // Nav row
            backButton.topAnchor.constraint(equalTo: contentView.topAnchor, constant: 56),
            backButton.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 20),
            backButton.widthAnchor.constraint(equalToConstant: 32),
            backButton.heightAnchor.constraint(equalToConstant: 32),

            navLabel.centerYAnchor.constraint(equalTo: backButton.centerYAnchor),
            navLabel.leadingAnchor.constraint(equalTo: backButton.trailingAnchor, constant: 8),

            // Chip
            updatedLabel.topAnchor.constraint(equalTo: backButton.bottomAnchor, constant: 20),
            updatedLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24),

            // Hero
            heroLabel.topAnchor.constraint(equalTo: updatedLabel.bottomAnchor, constant: 12),
            heroLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24),
            heroLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24),

            // Subtitle
            subtitleLabel.topAnchor.constraint(equalTo: heroLabel.bottomAnchor, constant: 12),
            subtitleLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 24),
            subtitleLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -24),

            // Terms stack
            termsStack.topAnchor.constraint(equalTo: subtitleLabel.bottomAnchor, constant: 28),
            termsStack.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 20),
            termsStack.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -20),

            // Contact card
            contactCard.topAnchor.constraint(equalTo: termsStack.bottomAnchor, constant: 28),
            contactCard.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: 20),
            contactCard.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -20),

            contactTitle.topAnchor.constraint(equalTo: contactCard.topAnchor, constant: 24),
            contactTitle.leadingAnchor.constraint(equalTo: contactCard.leadingAnchor, constant: 20),
            contactTitle.trailingAnchor.constraint(equalTo: contactCard.trailingAnchor, constant: -20),

            contactDesc.topAnchor.constraint(equalTo: contactTitle.bottomAnchor, constant: 8),
            contactDesc.leadingAnchor.constraint(equalTo: contactCard.leadingAnchor, constant: 20),
            contactDesc.trailingAnchor.constraint(equalTo: contactCard.trailingAnchor, constant: -20),

            contactButton.topAnchor.constraint(equalTo: contactDesc.bottomAnchor, constant: 20),
            contactButton.leadingAnchor.constraint(equalTo: contactCard.leadingAnchor, constant: 20),
            contactButton.bottomAnchor.constraint(equalTo: contactCard.bottomAnchor, constant: -24),

            // Footer
            footerLabel.topAnchor.constraint(equalTo: contactCard.bottomAnchor, constant: 24),
            footerLabel.centerXAnchor.constraint(equalTo: contentView.centerXAnchor),
            footerLabel.bottomAnchor.constraint(equalTo: contentView.bottomAnchor, constant: -32),
        ])
    }

    // MARK: - Helpers

    private func makePaddedLabel(text: String, color: UIColor, bg: UIColor) -> UILabel {
        let label = UILabel()
        label.text            = text
        label.font            = Theme.Font.caption(weight: .semibold)
        label.textColor       = color
        label.backgroundColor = bg
        label.layer.cornerRadius = 8
        label.clipsToBounds   = true
        label.textAlignment   = .center
        label.translatesAutoresizingMaskIntoConstraints = false
        label.heightAnchor.constraint(equalToConstant: 26).isActive = true
        return label
    }

    private func makeSectionRow(number: Int, section: TermsSection) -> UIView {
        let card = UIView()
        card.backgroundColor    = Theme.Color.card
        card.layer.cornerRadius = 16
        card.layer.shadowColor   = UIColor.black.cgColor
        card.layer.shadowOpacity = 0.06
        card.layer.shadowOffset  = CGSize(width: 0, height: 2)
        card.layer.shadowRadius  = 8
        card.translatesAutoresizingMaskIntoConstraints = false

        // Number badge
        let badge = UILabel()
        badge.text = "\(number)."
        badge.font = Theme.Font.body(weight: .bold)
        badge.textColor = Theme.Color.secondary
        badge.translatesAutoresizingMaskIntoConstraints = false

        // Title
        let titleLabel = UILabel()
        titleLabel.text = section.title
        titleLabel.font = Theme.Font.body(weight: .semibold)
        titleLabel.textColor = Theme.Color.textPrimary
        titleLabel.numberOfLines = 0
        titleLabel.translatesAutoresizingMaskIntoConstraints = false

        // Header row
        let headerStack = UIStackView(arrangedSubviews: [badge, titleLabel])
        headerStack.axis      = .horizontal
        headerStack.spacing   = 8
        headerStack.alignment = .top
        headerStack.translatesAutoresizingMaskIntoConstraints = false

        // Body
        let bodyLabel = UILabel()
        bodyLabel.text = section.body
        bodyLabel.font = Theme.Font.caption(weight: .regular)
        bodyLabel.textColor = Theme.Color.textSecondary
        bodyLabel.numberOfLines = 0
        bodyLabel.translatesAutoresizingMaskIntoConstraints = false

        // Bullet points
        let bulletStack = UIStackView()
        bulletStack.axis    = .vertical
        bulletStack.spacing = 6
        bulletStack.translatesAutoresizingMaskIntoConstraints = false

        for bullet in section.bullets {
            let bulletRow = UIStackView()
            bulletRow.axis      = .horizontal
            bulletRow.spacing   = 8
            bulletRow.alignment = .top

            let dot = UILabel()
            dot.text      = "•"
            dot.font      = Theme.Font.caption(weight: .semibold)
            dot.textColor = Theme.Color.secondary

            let bulletLabel = UILabel()
            bulletLabel.text          = bullet
            bulletLabel.font          = Theme.Font.caption(weight: .regular)
            bulletLabel.textColor     = Theme.Color.textSecondary
            bulletLabel.numberOfLines = 0

            bulletRow.addArrangedSubview(dot)
            bulletRow.addArrangedSubview(bulletLabel)
            bulletStack.addArrangedSubview(bulletRow)
        }

        let mainStack = UIStackView(arrangedSubviews: [headerStack, bodyLabel])
        if !section.bullets.isEmpty { mainStack.addArrangedSubview(bulletStack) }
        mainStack.axis    = .vertical
        mainStack.spacing = 8
        mainStack.translatesAutoresizingMaskIntoConstraints = false
        card.addSubview(mainStack)

        NSLayoutConstraint.activate([
            badge.widthAnchor.constraint(equalToConstant: 24),
            mainStack.topAnchor.constraint(equalTo: card.topAnchor, constant: 16),
            mainStack.leadingAnchor.constraint(equalTo: card.leadingAnchor, constant: 16),
            mainStack.trailingAnchor.constraint(equalTo: card.trailingAnchor, constant: -16),
            mainStack.bottomAnchor.constraint(equalTo: card.bottomAnchor, constant: -16),
        ])

        return card
    }

    // MARK: - Actions

    @objc private func backTapped() {
        navigationController?.popViewController(animated: true)
    }

    @objc private func contactTapped() {
        let address = "apps@indonesiainyourhand.com"
        let subject = "Ask Support"
        let encoded = subject.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) ?? subject
        if let url = URL(string: "mailto:\(address)?subject=\(encoded)") {
            UIApplication.shared.open(url)
        }
    }
}

// MARK: - Terms Data Model

struct TermsSection {
    let title: String
    let body: String
    let bullets: [String]
}

enum TermsData {
    static var sections: [TermsSection] {[
        TermsSection(
            title: L10n.termsSec1Title,
            body: L10n.termsSec1Body,
            bullets: []
        ),
        TermsSection(
            title: L10n.termsSec2Title,
            body: L10n.termsSec2Body,
            bullets: [
                L10n.termsSec2Bullet1,
                L10n.termsSec2Bullet2,
                L10n.termsSec2Bullet3,
            ]
        ),
        TermsSection(
            title: L10n.termsSec3Title,
            body: L10n.termsSec3Body,
            bullets: [
                L10n.termsSec3Bullet1,
                L10n.termsSec3Bullet2,
            ]
        ),
    ]}
}