//
//  FollowNotificationGroupTableViewCell.swift
//  Tusker
//
//  Created by Shadowfacts on 9/5/19.
//  Copyright © 2019 Shadowfacts. All rights reserved.
//

import UIKit
import Pachyderm

class FollowNotificationGroupTableViewCell: UITableViewCell {

    var delegate: TuskerNavigationDelegate?
    
    @IBOutlet weak var avatarStackView: UIStackView!
    @IBOutlet weak var actionLabel: UILabel!
    
    var group: NotificationGroup!
    
    override func awakeFromNib() {
        super.awakeFromNib()
        
        NotificationCenter.default.addObserver(self, selector: #selector(updateUIForPreferences), name: .preferencesChanged, object: nil)
    }
    
    @objc func updateUIForPreferences() {
        let people = group.notificationIDs.compactMap(MastodonCache.notification(for:)).map { $0.account }
        updateActionLabel(people: people)
        
        for case let imageView as UIImageView in avatarStackView.arrangedSubviews {
            imageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadius(for: imageView)
        }
    }

    func updateUI(group: NotificationGroup) {
        self.group = group
        
        let people = group.notificationIDs.compactMap(MastodonCache.notification(for:)).map { $0.account }
        
        updateActionLabel(people: people)
        
        avatarStackView.arrangedSubviews.forEach { $0.removeFromSuperview() }
        for account in people {
            let imageView = UIImageView()
            imageView.translatesAutoresizingMaskIntoConstraints = false
            imageView.layer.masksToBounds = true
            imageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadiusFraction * 30
            ImageCache.avatars.get(account.avatar) { (data) in
                guard let data = data, self.group.id == group.id else { return }
                DispatchQueue.main.async {
                    imageView.image = UIImage(data: data)
                }
            }
            avatarStackView.addArrangedSubview(imageView)
            NSLayoutConstraint.activate([
                imageView.widthAnchor.constraint(equalToConstant: 30),
                imageView.heightAnchor.constraint(equalToConstant: 30),
            ])
        }
    }
    
    func updateActionLabel(people: [Account]) {
        // todo: figure out how to localize this
        let peopleStr: String
        switch (people.count) {
        case 1:
            peopleStr = people.first!.realDisplayName
        case 2:
            peopleStr = people.first!.realDisplayName + " and " + people.last!.realDisplayName
        default:
            peopleStr = people.dropLast().map { $0.realDisplayName }.joined(separator: ", ") + ", and " + people.last!.realDisplayName

        }
        actionLabel.text = "Followed by \(peopleStr)"
    }

}