MessageKit/Sources/Views/Cells/TextMessageCell.swift

// 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

/// A subclass of `MessageContentCell` used to display text messages.
open class TextMessageCell: MessageContentCell {
  /// The label used to display the message's text.
  open var messageLabel = MessageLabel()

  // MARK: - Properties

  /// The `MessageCellDelegate` for the cell.
  open override weak var delegate: MessageCellDelegate? {
    didSet {
      messageLabel.delegate = delegate
    }
  }

  // MARK: - Methods

  open override func apply(_ layoutAttributes: UICollectionViewLayoutAttributes) {
    super.apply(layoutAttributes)
    if let attributes = layoutAttributes as? MessagesCollectionViewLayoutAttributes {
      messageLabel.textInsets = attributes.messageLabelInsets
      messageLabel.messageLabelFont = attributes.messageLabelFont
      messageLabel.frame = messageContainerView.bounds
    }
  }

  open override func prepareForReuse() {
    super.prepareForReuse()
    messageLabel.attributedText = nil
    messageLabel.text = nil
  }

  open override func setupSubviews() {
    super.setupSubviews()
    messageContainerView.addSubview(messageLabel)
  }

  open override func configure(
    with message: MessageType,
    at indexPath: IndexPath,
    and messagesCollectionView: MessagesCollectionView)
  {
    super.configure(with: message, at: indexPath, and: messagesCollectionView)

    guard let displayDelegate = messagesCollectionView.messagesDisplayDelegate else {
      fatalError(MessageKitError.nilMessagesDisplayDelegate)
    }

    let enabledDetectors = displayDelegate.enabledDetectors(for: message, at: indexPath, in: messagesCollectionView)

    messageLabel.configure {
      messageLabel.enabledDetectors = enabledDetectors
      for detector in enabledDetectors {
        let attributes = displayDelegate.detectorAttributes(for: detector, and: message, at: indexPath)
        messageLabel.setAttributes(attributes, detector: detector)
      }
      let textMessageKind = message.kind.textMessageKind
      switch textMessageKind {
      case .text(let text), .emoji(let text):
        let textColor = displayDelegate.textColor(for: message, at: indexPath, in: messagesCollectionView)
        messageLabel.text = text
        messageLabel.textColor = textColor
        if let font = messageLabel.messageLabelFont {
          messageLabel.font = font
        }
      case .attributedText(let text):
        messageLabel.attributedText = text
      default:
        break
      }
    }
  }

  /// Used to handle the cell's contentView's tap gesture.
  /// Return false when the contentView does not need to handle the gesture.
  open override func cellContentView(canHandle touchPoint: CGPoint) -> Bool {
    messageLabel.handleGesture(touchPoint)
  }
}