//
//  PostView.swift
//  RedditClient
//
//  Created by Denis on 3/14/23.
//

import SDWebImage
import UIKit

class RedditPostView: UIView {
    private let postDetailsView = PostDetailsView()

    private let postTitleLabel = PostTitleLabel()
    private let postImageView = UIImageView()
    private let postActionsView = PostActionsView()

    private var bookmarkIcon: BookmarkIconView!

    private var postActionsViewTopToTitleConstraint: NSLayoutConstraint?
    private var postActionsViewTopToImageConstraint: NSLayoutConstraint?

    private var postImageViewHeightConstraint: NSLayoutConstraint?

    weak var delegate: RedditPostDelegate?

    private var post: Post?

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupViews()
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private func setupViews() {
        postImageView.isHidden = true

        postImageView.contentMode = .scaleAspectFit
        postImageView.backgroundColor = .secondarySystemBackground

        bookmarkIcon = BookmarkIconView(
            frame: CGRect(
                x: UIScreen.main.bounds.width - 18,
                y: 4,
                width: 12,
                height: 20
            )
        )

        addSubview(postDetailsView)
        addSubview(bookmarkIcon)
        addSubview(postTitleLabel)
        addSubview(postImageView)
        addSubview(postActionsView)

        // Add the following lines to create new top constraints
        postActionsViewTopToTitleConstraint = postActionsView.topAnchor.constraint(equalTo: postTitleLabel.bottomAnchor, constant: 8)
        postActionsViewTopToImageConstraint = postActionsView.topAnchor.constraint(equalTo: postImageView.bottomAnchor, constant: 8)

        // Set the initial state (assuming there is no image initially)
        postActionsViewTopToImageConstraint?.isActive = false
        postActionsViewTopToTitleConstraint?.isActive = true

        postImageView.translatesAutoresizingMaskIntoConstraints = false

        translatesAutoresizingMaskIntoConstraints = false

        NSLayoutConstraint.activate([
            postDetailsView.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: 8),
            postDetailsView.centerYAnchor.constraint(equalTo: bookmarkIcon.centerYAnchor),

            postTitleLabel.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: 8),
            postTitleLabel.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -8),
            postTitleLabel.topAnchor.constraint(equalTo: bookmarkIcon.bottomAnchor, constant: 8),

            postImageView.leadingAnchor.constraint(equalTo: self.leadingAnchor),
            postImageView.trailingAnchor.constraint(equalTo: self.trailingAnchor),
            postImageView.topAnchor.constraint(equalTo: postTitleLabel.bottomAnchor, constant: 8),
            postImageView.heightAnchor.constraint(lessThanOrEqualToConstant: 300),

            postActionsView.leadingAnchor.constraint(equalTo: self.leadingAnchor),
            postActionsView.trailingAnchor.constraint(equalTo: self.trailingAnchor),

            self.bottomAnchor.constraint(equalTo: postActionsView.bottomAnchor, constant: 8)
        ])
    }

    func toggleFavorite() {
        PersistenceManager.updateWith(favorite: post!, actionType: post!.isSaved ? .remove : .add) { [weak self] error in
            guard let self else { return }

            guard error != nil else {
                self.toggleBookmarkIconState()
                return
            }
        }
    }

    private func toggleBookmarkIconState() {
        DispatchQueue.main.async { [weak self] in
            guard let self else { return }
            UIView.transition(
                with: self,
                duration: 0.15,
                options: .transitionCrossDissolve) {
                    self.bookmarkIcon.isHidden.toggle()
                }
        }
    }

    func setBlank() {
        self.postImageView.image = nil
        self.postImageView.sd_cancelCurrentImageLoad()
        postActionsViewTopToImageConstraint?.isActive = false
        postActionsViewTopToTitleConstraint?.isActive = true
    }

    func configure(post: Post) {
        self.post = post

        postActionsView.shareButton.addTarget(self, action: #selector(shareButtonTapped), for: .touchUpInside)

        postDetailsView.configure(author: post.data.author, postTime: post.data.createdAt, domain: post.data.subreddit)

        bookmarkIcon.isHidden = !post.isSaved
        postTitleLabel.text = post.data.title

        if let imageLink = post.data.preview?.images.first?.source.url {
            postImageViewHeightConstraint = postImageView.heightAnchor.constraint(lessThanOrEqualToConstant: 300)

            postImageViewHeightConstraint?.isActive = true

            postActionsViewTopToTitleConstraint?.isActive = false
            postActionsViewTopToImageConstraint?.isActive = true
            postImageView.isHidden = false

            postImageView.sd_setImage(with: imageLink, placeholderImage: UIImage().withTintColor(.secondaryLabel))
        } else {
            postImageView.isHidden = true
            postActionsViewTopToImageConstraint?.isActive = false
            postActionsViewTopToTitleConstraint?.isActive = true
        }

        postActionsView.configure(post: post)
    }

    @objc private func shareButtonTapped() {
        delegate?.didTapShareButton(for: post!)
    }
}