//
//  ProfileViewController.swift
//  suixinkan
//

import PhotosUI
import SnapKit
import UIKit

/// 个人信息页，展示用户资料、账号状态和设置入口。
final class ProfileViewController: UIViewController {

    private let viewModel = ProfileViewModel()

    private let avatarImageView = UIImageView()
    private let nicknameLabel = UILabel()
    private let uidLabel = UILabel()
    private let editButton = UIButton(type: .system)

    private lazy var tableView: UITableView = {
        let table = UITableView(frame: .zero, style: .insetGrouped)
        table.dataSource = self
        table.delegate = self
        return table
    }()

    private lazy var refreshControl = UIRefreshControl()

    override func viewDidLoad() {
        super.viewDidLoad()
        title = "个人信息"
        view.backgroundColor = UIColor(hex: 0xF7FAFF)
        setupHeader()
        view.addSubview(tableView)
        tableView.snp.makeConstraints { make in
            make.top.equalTo(view.safeAreaLayoutGuide).offset(150)
            make.leading.trailing.bottom.equalToSuperview()
        }
        refreshControl.addTarget(self, action: #selector(refreshPulled), for: .valueChanged)
        tableView.refreshControl = refreshControl

        viewModel.onChange = { [weak self] in self?.applyViewModel() }
        editButton.addTarget(self, action: #selector(editTapped), for: .touchUpInside)

        let avatarTap = UITapGestureRecognizer(target: self, action: #selector(pickAvatar))
        avatarImageView.isUserInteractionEnabled = true
        avatarImageView.addGestureRecognizer(avatarTap)

        Task { await reloadProfile(showToast: false) }
    }

    private func setupHeader() {
        let header = UIView()
        header.backgroundColor = .white
        header.layer.cornerRadius = 17
        view.addSubview(header)

        avatarImageView.layer.cornerRadius = 43
        avatarImageView.clipsToBounds = true
        avatarImageView.contentMode = .scaleAspectFill
        avatarImageView.backgroundColor = AppDesignUIKit.primarySoft

        nicknameLabel.font = .systemFont(ofSize: 24, weight: .semibold)
        nicknameLabel.textColor = UIColor(hex: 0x252525)
        uidLabel.font = .systemFont(ofSize: 18, weight: .semibold)
        uidLabel.textColor = UIColor(hex: 0x606A7A)

        editButton.setImage(UIImage(systemName: "pencil"), for: .normal)
        editButton.tintColor = .white
        editButton.backgroundColor = AppDesignUIKit.primary
        editButton.layer.cornerRadius = 22

        header.addSubview(avatarImageView)
        header.addSubview(nicknameLabel)
        header.addSubview(uidLabel)
        header.addSubview(editButton)

        header.snp.makeConstraints { make in
            make.top.equalTo(view.safeAreaLayoutGuide).offset(16)
            make.leading.trailing.equalToSuperview().inset(19)
            make.height.equalTo(132)
        }
        avatarImageView.snp.makeConstraints { make in
            make.leading.equalToSuperview().offset(18)
            make.centerY.equalToSuperview()
            make.width.height.equalTo(86)
        }
        nicknameLabel.snp.makeConstraints { make in
            make.leading.equalTo(avatarImageView.snp.trailing).offset(14)
            make.trailing.lessThanOrEqualTo(editButton.snp.leading).offset(-8)
            make.top.equalTo(avatarImageView).offset(8)
        }
        uidLabel.snp.makeConstraints { make in
            make.leading.equalTo(nicknameLabel)
            make.top.equalTo(nicknameLabel.snp.bottom).offset(8)
        }
        editButton.snp.makeConstraints { make in
            make.trailing.equalToSuperview().inset(18)
            make.centerY.equalToSuperview()
            make.width.height.equalTo(44)
        }
    }

    private func applyViewModel() {
        nicknameLabel.text = viewModel.displayNickname
        uidLabel.text = "UID:  \(appServices.accountContext.profile?.userId ?? "--")"
        if let data = viewModel.pendingAvatarData, let image = UIImage(data: data) {
            avatarImageView.image = image
        } else {
            avatarImageView.loadRemoteAvatar(urlString: viewModel.displayAvatarURL)
        }
        editButton.setImage(UIImage(systemName: viewModel.isEditingProfile ? "checkmark" : "pencil"), for: .normal)
        editButton.isEnabled = !viewModel.isSaving
        tableView.reloadData()
    }

    @objc private func refreshPulled() {
        Task {
            await reloadProfile(showToast: true)
            refreshControl.endRefreshing()
        }
    }

    private func reloadProfile(showToast: Bool) async {
        do {
            try await appServices.globalLoading.withOptionalLoading(!showToast && viewModel.userInfo == nil, message: "加载资料...") {
                try await self.viewModel.reload(api: self.appServices.profileAPI)
            }
        } catch {
            if showToast { self.showToast(error.localizedDescription) }
        }
    }

    @objc private func editTapped() {
        if viewModel.isEditingProfile {
            Task { await saveProfileEdits() }
        } else {
            viewModel.beginEditing()
            presentNicknameEditor()
        }
    }

    private func presentNicknameEditor() {
        let alert = UIAlertController(title: "编辑昵称", message: nil, preferredStyle: .alert)
        alert.addTextField { [weak self] field in
            field.text = self?.viewModel.editingNickname
            field.placeholder = "请输入昵称"
        }
        alert.addAction(UIAlertAction(title: "取消", style: .cancel) { [weak self] _ in
            self?.viewModel.cancelEditing()
        })
        alert.addAction(UIAlertAction(title: "保存", style: .default) { [weak self] _ in
            guard let self else { return }
            self.viewModel.editingNickname = alert.textFields?.first?.text ?? ""
            Task { await self.saveProfileEdits() }
        })
        present(alert, animated: true)
    }

    private func saveProfileEdits() async {
        guard let scenicId = appServices.accountContext.currentScenic?.id else {
            showToast("请先选择景区")
            return
        }
        do {
            try await appServices.globalLoading.withLoading(message: "保存中...") {
                try await self.viewModel.saveProfile(
                    api: self.appServices.profileAPI,
                    uploader: self.appServices.ossUploadService,
                    scenicId: scenicId
                )
            }
            showToast("资料已更新")
        } catch {
            showToast(error.localizedDescription)
        }
    }

    @objc private func pickAvatar() {
        var config = PHPickerConfiguration()
        config.filter = .images
        config.selectionLimit = 1
        let picker = PHPickerViewController(configuration: config)
        picker.delegate = self
        present(picker, animated: true)
    }

    @objc private func logoutTapped() {
        let alert = UIAlertController(title: "确认退出当前账号？", message: nil, preferredStyle: .alert)
        alert.addAction(UIAlertAction(title: "取消", style: .cancel))
        alert.addAction(UIAlertAction(title: "退出登录", style: .destructive) { [weak self] _ in
            guard let self else { return }
            self.appServices.authSessionCoordinator.logout(
                appSession: self.appServices.appSession,
                accountContext: self.appServices.accountContext,
                permissionContext: self.appServices.permissionContext,
                scenicSpotContext: self.appServices.scenicSpotContext,
                appRouter: self.appServices.appRouter,
                toastCenter: self.appServices.toastCenter
            )
        })
        present(alert, animated: true)
    }
}

extension ProfileViewController: UITableViewDataSource, UITableViewDelegate {
    func numberOfSections(in tableView: UITableView) -> Int { 2 }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        section == 0 ? 5 : 1
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(style: .value1, reuseIdentifier: nil)
        if indexPath.section == 1 {
            cell.textLabel?.text = "退出登录"
            cell.textLabel?.textColor = UIColor(hex: 0xEF4444)
            cell.textLabel?.textAlignment = .center
            return cell
        }
        switch indexPath.row {
        case 0:
            cell.textLabel?.text = "姓名"
            cell.detailTextLabel?.text = viewModel.displayRealName
        case 1:
            cell.textLabel?.text = "当前账号"
            cell.detailTextLabel?.text = appServices.accountContext.profile?.displayName ?? "--"
            cell.accessoryType = .disclosureIndicator
        case 2:
            cell.textLabel?.text = "手机号"
            cell.detailTextLabel?.text = viewModel.displayPhone
        case 3:
            cell.textLabel?.text = "实名认证"
            cell.detailTextLabel?.text = viewModel.realNameStatusText
            cell.accessoryType = .disclosureIndicator
        default:
            cell.textLabel?.text = "设置"
            cell.accessoryType = .disclosureIndicator
        }
        cell.selectionStyle = indexPath.row == 0 || indexPath.row == 2 ? .none : .default
        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        tableView.deselectRow(at: indexPath, animated: true)
        if indexPath.section == 1 {
            logoutTapped()
            return
        }
        switch indexPath.row {
        case 1:
            HomeMenuRouting.pushProfile(.accountSwitch, from: self)
        case 3:
            HomeMenuRouting.pushProfile(.realNameAuth, from: self)
        case 4:
            HomeMenuRouting.pushProfile(.settings, from: self)
        default:
            break
        }
    }
}

extension ProfileViewController: PHPickerViewControllerDelegate {
    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.prepareAvatarImage(data: data)
                } catch {
                    self.showToast(error.localizedDescription)
                }
            }
        }
    }
}