//
//  InstanceTableViewCell.swift
//  Tusker
//
//  Created by Shadowfacts on 9/15/19.
//  Copyright © 2019 Shadowfacts. All rights reserved.
//

import UIKit
import Pachyderm

class InstanceTableViewCell: UITableViewCell {

    @IBOutlet weak var thumbnailImageView: UIImageView!
    @IBOutlet weak var domainLabel: UILabel!
    @IBOutlet weak var adultLabel: UILabel!
    @IBOutlet weak var descriptionTextView: ContentTextView!
    
    var instance: InstanceV1?
    var selectorInstance: InstanceSelector.Instance?
    
    private var thumbnailTask: Task<Void, Never>?
    
    deinit {
        thumbnailTask?.cancel()
    }
    
    override func awakeFromNib() {
        super.awakeFromNib()
        
        thumbnailImageView.layer.masksToBounds = true
        thumbnailImageView.layer.cornerRadius = 5
        
        domainLabel.font = UIFontMetrics(forTextStyle: .title1).scaledFont(for: .systemFont(ofSize: 22, weight: .bold))
        domainLabel.adjustsFontForContentSizeCategory = true
        
        adultLabel.layer.masksToBounds = true
        adultLabel.layer.cornerRadius = 0.5 * adultLabel.bounds.height
        
        descriptionTextView.adjustsFontForContentSizeCategory = true
    }
    
    override func updateConfiguration(using state: UICellConfigurationState) {
        backgroundConfiguration = .appListGroupedCell(for: state)
    }
    
    func updateUI(instance: InstanceSelector.Instance) {
        self.selectorInstance = instance
        self.instance = nil
        
        domainLabel.text = instance.domain
        adultLabel.isHidden = instance.category != "adult"
        descriptionTextView.setBodyTextFromHTML(instance.description)
        updateThumbnail(url: instance.proxiedThumbnailURL)
    }
    
    func updateUI(instance: InstanceV1) {
        self.instance = instance
        self.selectorInstance = nil

        domainLabel.text = URLComponents(string: instance.uri)?.host ?? instance.uri
        adultLabel.isHidden = true
        descriptionTextView.setBodyTextFromHTML(instance.shortDescription ?? instance.description)
        
        if let thumbnail = instance.thumbnail {
            updateThumbnail(url: thumbnail)
        } else {
            thumbnailImageView.image = nil
        }
    }
    
    private func updateThumbnail(url: URL) {
        thumbnailImageView.image = nil
        thumbnailTask = Task {
            guard let image = await ImageCache.attachments.get(url).1,
                  !Task.isCancelled else {
                return
            }
            thumbnailImageView.image = image
        }
    }
    
    override func prepareForReuse() {
        super.prepareForReuse()
        
        thumbnailTask?.cancel()
        instance = nil
        selectorInstance = nil
    }

}