// MIT License
//
// Copyright (c) 2017-2019 MessageKit
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import UIKit

open class LinkPreviewMessageCell: TextMessageCell {
  // MARK: Open

  open override func apply(_ layoutAttributes: UICollectionViewLayoutAttributes) {
    super.apply(layoutAttributes)
    guard let attributes = layoutAttributes as? MessagesCollectionViewLayoutAttributes else { return }
    linkPreviewView.titleLabel.font = attributes.linkPreviewFonts.titleFont
    linkPreviewView.teaserLabel.font = attributes.linkPreviewFonts.teaserFont
    linkPreviewView.domainLabel.font = attributes.linkPreviewFonts.domainFont
  }

  open override func configure(
    with message: MessageType,
    at indexPath: IndexPath,
    and messagesCollectionView: MessagesCollectionView)
  {
    let displayDelegate = messagesCollectionView.messagesDisplayDelegate

    if let textColor: UIColor = displayDelegate?.textColor(for: message, at: indexPath, in: messagesCollectionView) {
      linkPreviewView.titleLabel.textColor = textColor
      linkPreviewView.teaserLabel.textColor = textColor
      linkPreviewView.domainLabel.textColor = textColor
    }

    guard case MessageKind.linkPreview(let linkItem) = message.kind else {
      fatalError("LinkPreviewMessageCell received unhandled MessageDataType: \(message.kind)")
    }

    super.configure(with: message, at: indexPath, and: messagesCollectionView)

    linkPreviewView.titleLabel.text = linkItem.title
    linkPreviewView.teaserLabel.text = linkItem.teaser
    linkPreviewView.domainLabel.text = linkItem.url.host?.lowercased()
    linkPreviewView.imageView.image = linkItem.thumbnailImage
    linkURL = linkItem.url

    displayDelegate?.configureLinkPreviewImageView(
      linkPreviewView.imageView,
      for: message,
      at: indexPath,
      in: messagesCollectionView)
  }

  open override func prepareForReuse() {
    super.prepareForReuse()
    linkPreviewView.titleLabel.text = nil
    linkPreviewView.teaserLabel.text = nil
    linkPreviewView.domainLabel.text = nil
    linkPreviewView.imageView.image = nil
    linkURL = nil
  }

  open override func handleTapGesture(_ gesture: UIGestureRecognizer) {
    let touchLocation = gesture.location(in: linkPreviewView)

    guard linkPreviewView.frame.contains(touchLocation), let url = linkURL else {
      super.handleTapGesture(gesture)
      return
    }
    delegate?.didSelectURL(url)
  }

  // MARK: Public

  public lazy var linkPreviewView: LinkPreviewView = {
    let view = LinkPreviewView()
    view.translatesAutoresizingMaskIntoConstraints = false
    messageContainerView.addSubview(view)

    NSLayoutConstraint.activate([
      view.leadingAnchor.constraint(
        equalTo: messageContainerView.leadingAnchor,
        constant: messageLabel.textInsets.left),
      view.trailingAnchor.constraint(
        equalTo: messageContainerView.trailingAnchor,
        constant: messageLabel.textInsets.right * -1),
      view.bottomAnchor.constraint(
        equalTo: messageContainerView.bottomAnchor,
        constant: messageLabel.textInsets.bottom * -1),
    ])
    return view
  }()

  // MARK: Private

  private var linkURL: URL?
}