session-ios/Session/Conversations/Message Cells/InfoMessageCell.swift

// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.

import UIKit
import SessionUIKit
import SessionMessagingKit

final class InfoMessageCell: MessageCell {
    private static let iconSize: CGFloat = 16
    private static let inset = Values.mediumSpacing
    
    private var isHandlingLongPress: Bool = false
    
    override var contextSnapshotView: UIView? { return label }
    
    // MARK: - UI
    
    private lazy var iconImageViewWidthConstraint = iconImageView.set(.width, to: InfoMessageCell.iconSize)
    private lazy var iconImageViewHeightConstraint = iconImageView.set(.height, to: InfoMessageCell.iconSize)
    
    private lazy var iconImageView: UIImageView = UIImageView()

    private lazy var label: UILabel = {
        let result: UILabel = UILabel()
        result.font = .boldSystemFont(ofSize: Values.verySmallFontSize)
        result.themeTextColor = .textPrimary
        result.textAlignment = .center
        result.lineBreakMode = .byWordWrapping
        result.numberOfLines = 0
        
        return result
    }()

    private lazy var stackView: UIStackView = {
        let result: UIStackView = UIStackView(arrangedSubviews: [ iconImageView, label ])
        result.axis = .vertical
        result.alignment = .center
        result.spacing = Values.smallSpacing
        
        return result
    }()

    // MARK: - Lifecycle
    
    override func setUpViewHierarchy() {
        super.setUpViewHierarchy()
        
        iconImageViewWidthConstraint.isActive = true
        iconImageViewHeightConstraint.isActive = true
        addSubview(stackView)
        
        stackView.pin(.left, to: .left, of: self, withInset: Values.massiveSpacing)
        stackView.pin(.top, to: .top, of: self, withInset: InfoMessageCell.inset)
        stackView.pin(.right, to: .right, of: self, withInset: -Values.massiveSpacing)
        stackView.pin(.bottom, to: .bottom, of: self, withInset: -InfoMessageCell.inset)
    }
    
    override func setUpGestureRecognizers() {
        let longPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress))
        addGestureRecognizer(longPressRecognizer)
    }

    // MARK: - Updating
    
    override func update(
        with cellViewModel: MessageViewModel,
        mediaCache: NSCache<NSString, AnyObject>,
        playbackInfo: ConversationViewModel.PlaybackInfo?,
        showExpandedReactions: Bool,
        lastSearchText: String?
    ) {
        guard cellViewModel.variant.isInfoMessage else { return }
        
        self.viewModel = cellViewModel
        
        let icon: UIImage? = {
            switch cellViewModel.variant {
                case .infoDisappearingMessagesUpdate:
                    return UIImage(systemName: "timer")
                    
                case .infoMediaSavedNotification: return UIImage(named: "ic_download")
                    
                default: return nil
            }
        }()
        
        if let icon = icon {
            iconImageView.image = icon.withRenderingMode(.alwaysTemplate)
            iconImageView.themeTintColor = .textPrimary
        }
        
        iconImageViewWidthConstraint.constant = (icon != nil) ? InfoMessageCell.iconSize : 0
        iconImageViewHeightConstraint.constant = (icon != nil) ? InfoMessageCell.iconSize : 0
        
        self.label.text = cellViewModel.body
    }
    
    override func dynamicUpdate(with cellViewModel: MessageViewModel, playbackInfo: ConversationViewModel.PlaybackInfo?) {
    }
    
    // MARK: - Interaction
    
    @objc func handleLongPress(_ gestureRecognizer: UITapGestureRecognizer) {
        if [ .ended, .cancelled, .failed ].contains(gestureRecognizer.state) {
            isHandlingLongPress = false
            return
        }
        guard !isHandlingLongPress, let cellViewModel: MessageViewModel = self.viewModel else { return }
        
        delegate?.handleItemLongPressed(cellViewModel)
        isHandlingLongPress = true
    }
}