//
//  ProfileHeaderTableViewCell.swift
//  Tusker
//
//  Created by Shadowfacts on 8/27/18.
//  Copyright © 2018 Shadowfacts. All rights reserved.
//

import UIKit
import Pachyderm
import Combine

protocol ProfileHeaderTableViewCellDelegate: TuskerNavigationDelegate {
    func showMoreOptions(cell: ProfileHeaderTableViewCell)
}

class ProfileHeaderTableViewCell: UITableViewCell {
    
    weak var delegate: ProfileHeaderTableViewCellDelegate?
    var mastodonController: MastodonController! { delegate?.apiController }

    @IBOutlet weak var headerImageView: UIImageView!
    @IBOutlet weak var avatarContainerView: UIView!
    @IBOutlet weak var avatarImageView: UIImageView!
    @IBOutlet weak var displayNameLabel: EmojiLabel!
    @IBOutlet weak var usernameLabel: UILabel!
    @IBOutlet weak var followsYouLabel: UILabel!
    @IBOutlet weak var noteTextView: StatusContentTextView!
    @IBOutlet weak var fieldsStackView: UIStackView!
    @IBOutlet weak var fieldNamesStackView: UIStackView!
    @IBOutlet weak var fieldValuesStackView: UIStackView!
    @IBOutlet weak var moreButton: VisualEffectImageButton!
    
    var accountID: String!
    
    var avatarRequest: ImageCache.Request?
    var headerRequest: ImageCache.Request?
    
    private var accountUpdater: Cancellable?

    override func awakeFromNib() {
        avatarContainerView.layer.masksToBounds = true
        avatarImageView.layer.masksToBounds = true
        avatarImageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(avatarPressed)))
        avatarImageView.isUserInteractionEnabled = true
        headerImageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(headerPressed)))
        headerImageView.isUserInteractionEnabled = true
        
        moreButton.layer.cornerRadius = 16
        moreButton.layer.masksToBounds = true
        
        if #available(iOS 13.4, *) {
            moreButton.addInteraction(UIPointerInteraction(delegate: self))
        }
        if #available(iOS 14.0, *) {
            moreButton.showsMenuAsPrimaryAction = true
            moreButton.isContextMenuInteractionEnabled = true
        }
        
        NotificationCenter.default.addObserver(self, selector: #selector(updateUIForPreferences), name: .preferencesChanged, object: nil)
    }
    
    func updateUI(for accountID: String) {
        guard accountID != self.accountID else { return }
        self.accountID = accountID
        
        guard let account = mastodonController.persistentContainer.account(for: accountID) else { fatalError("Missing cached account \(accountID)") }
        
        updateUIForPreferences()
        
        usernameLabel.text = "@\(account.acct)"
        
        avatarRequest = ImageCache.avatars.get(account.avatar) { [weak self] (data) in
            guard let self = self, let data = data, self.accountID == accountID else { return }
            self.avatarRequest = nil
            DispatchQueue.main.async {
                self.avatarImageView.image = UIImage(data: data)
            }
        }
        headerRequest = ImageCache.headers.get(account.header) { [weak self] (data) in
            guard let self = self, let data = data, self.accountID == accountID else { return }
            self.headerRequest = nil
            DispatchQueue.main.async {
                self.headerImageView.image = UIImage(data: data)
            }
        }
        
        if #available(iOS 14.0, *) {
            moreButton.menu = UIMenu(title: "", image: nil, identifier: nil, options: [], children: actionsForProfile(accountID: accountID, sourceView: moreButton))
        }
        
        noteTextView.navigationDelegate = delegate
        noteTextView.setTextFromHtml(account.note)
        noteTextView.setEmojis(account.emojis)
        
        // don't show relationship label for the user's own account
        if accountID != mastodonController.account.id {
            let request = Client.getRelationships(accounts: [accountID])
            mastodonController.run(request) { (response) in
                if case let .success(results, _) = response, let relationship = results.first {
                    DispatchQueue.main.async {
                        self.followsYouLabel.isHidden = !relationship.followedBy
                    }
                }
            }
        }
        
        fieldsStackView.isHidden = account.fields.isEmpty

        fieldNamesStackView.arrangedSubviews.forEach { $0.removeFromSuperview() }
        fieldValuesStackView.arrangedSubviews.forEach { $0.removeFromSuperview() }
        for field in account.fields {
            let nameLabel = UILabel()
            nameLabel.text = field.name
            nameLabel.font = .boldSystemFont(ofSize: 17)
            nameLabel.textAlignment = .right
            nameLabel.numberOfLines = 0
            nameLabel.lineBreakMode = .byWordWrapping
            nameLabel.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
            fieldNamesStackView.addArrangedSubview(nameLabel)

            let valueTextView = ContentTextView()
            valueTextView.isSelectable = false
            valueTextView.font = .systemFont(ofSize: 17)
            valueTextView.setTextFromHtml(field.value)
            valueTextView.setEmojis(account.emojis)
            valueTextView.textAlignment = .left
            valueTextView.awakeFromNib()
            valueTextView.navigationDelegate = delegate
            valueTextView.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
            fieldValuesStackView.addArrangedSubview(valueTextView)
            
            nameLabel.heightAnchor.constraint(equalTo: valueTextView.heightAnchor).isActive = true
        }

        if accountUpdater == nil {
            accountUpdater = mastodonController.persistentContainer.accountSubject
                .filter { [unowned self] in $0 == self.accountID }
                .receive(on: DispatchQueue.main)
                .sink { [unowned self] in self.updateUI(for: $0) }
        }
    }

    @objc func updateUIForPreferences() {
        guard let account = mastodonController.persistentContainer.account(for: accountID) else { fatalError("Missing cached account \(accountID!)") }
        
        avatarContainerView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadius(for: avatarContainerView)
        avatarImageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadius(for: avatarImageView)
        displayNameLabel.updateForAccountDisplayName(account: account)
    }
    
    override func prepareForReuse() {
        avatarRequest?.cancel()
        headerRequest?.cancel()
    }
    
    @IBAction func morePressed(_ sender: Any) {
        delegate?.showMoreOptions(cell: self)
    }
    
    @objc func avatarPressed() {
        guard let account = mastodonController.persistentContainer.account(for: accountID) else { fatalError("Missing cached account \(accountID!)") }
        delegate?.showLoadingLargeImage(url: account.avatar, cache: .avatars, description: nil, animatingFrom: avatarImageView)
    }
    
    @objc func headerPressed() {
        guard let account = mastodonController.persistentContainer.account(for: accountID) else { fatalError("Missing cached account \(accountID!)") }
        delegate?.showLoadingLargeImage(url: account.header, cache: .headers, description: nil, animatingFrom: headerImageView)
    }
    
}

@available(iOS 13.4, *)
extension ProfileHeaderTableViewCell: UIPointerInteractionDelegate {
    func pointerInteraction(_ interaction: UIPointerInteraction, styleFor region: UIPointerRegion) -> UIPointerStyle? {
        let preview = UITargetedPreview(view: moreButton)
        return UIPointerStyle(effect: .lift(preview), shape: .none)
    }
}

extension ProfileHeaderTableViewCell: MenuPreviewProvider {
    var navigationDelegate: TuskerNavigationDelegate? {
        delegate
    }
}