Tusker/Tusker/Screens/Notifications/FollowRequestNotificationViewController.swift

//
//  FollowRequestNotificationViewController.swift
//  Tusker
//
//  Created by Shadowfacts on 5/19/24.
//  Copyright © 2024 Shadowfacts. All rights reserved.
//

import UIKit
import Pachyderm

class FollowRequestNotificationViewController: UIViewController, CollectionViewController {
    
    private let mastodonController: MastodonController
    private let notification: Pachyderm.Notification
    
    var collectionView: UICollectionView! {
        view as? UICollectionView
    }
    private var dataSource: UICollectionViewDiffableDataSource<Section, Item>!
    
    init(notification: Pachyderm.Notification, mastodonController: MastodonController) {
        precondition(notification.kind == .followRequest)
        self.mastodonController = mastodonController
        self.notification = notification
        
        super.init(nibName: nil, bundle: nil)
        
        title = "Follow Request"
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func loadView() {
        let layout = UICollectionViewCompositionalLayout { sectionIndex, environment in
            var config = UICollectionLayoutListConfiguration(appearance: .grouped)
            config.backgroundColor = .appGroupedBackground
            let section = NSCollectionLayoutSection.list(using: config, layoutEnvironment: environment)
            section.readableContentInset(in: environment)
            return section
        }
        view = UICollectionView(frame: .zero, collectionViewLayout: layout)
        collectionView.delegate = self
        collectionView.dragDelegate = self
        collectionView.allowsFocus = true
        dataSource = createDataSource()
    }
    
    private func createDataSource() -> UICollectionViewDiffableDataSource<Section, Item> {
        let followRequestCell = UICollectionView.CellRegistration<FollowRequestNotificationCollectionViewCell, Void> { [unowned self] cell, indexPath, itemIdentifier in
            cell.delegate = self
            cell.updateUI(notification: self.notification)
        }
        return UICollectionViewDiffableDataSource(collectionView: collectionView) { collectionView, indexPath, itemIdentifier in
            return collectionView.dequeueConfiguredReusableCell(using: followRequestCell, for: indexPath, item: ())
        }
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        var snapshot = NSDiffableDataSourceSnapshot<Section, Item>()
        snapshot.appendSections([.notifications])
        snapshot.appendItems([.notification])
        dataSource.apply(snapshot, animatingDifferences: false)
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        clearSelectionOnAppear(animated: animated)
    }
}

extension FollowRequestNotificationViewController {
    enum Section {
        case notifications
    }
    enum Item {
        case notification
    }
}

extension FollowRequestNotificationViewController: UICollectionViewDelegate {
    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        selected(account: notification.account.id)
    }
    
    func collectionView(_ collectionView: UICollectionView, contextMenuConfigurationForItemAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {
        guard let cell = collectionView.cellForItem(at: indexPath) else {
            return nil
        }
        let accountID = notification.account.id
        return UIContextMenuConfiguration {
            ProfileViewController(accountID: accountID, mastodonController: self.mastodonController)
        } actionProvider: { _ in
            let cell = cell as! FollowRequestNotificationCollectionViewCell
            let acceptRejectChildren = [
                UIAction(title: "Accept", image: UIImage(systemName: "checkmark.circle"), handler: { _ in cell.acceptButtonPressed() }),
                UIAction(title: "Reject", image: UIImage(systemName: "xmark.circle"), handler: { _ in cell.rejectButtonPressed() }),
            ]
            let acceptRejectMenu: UIMenu
            if #available(iOS 16.0, *) {
                acceptRejectMenu = UIMenu(options: .displayInline, preferredElementSize: .medium, children: acceptRejectChildren)
            } else {
                acceptRejectMenu = UIMenu(options: .displayInline, children: acceptRejectChildren)
            }
            return UIMenu(children: [
                acceptRejectMenu,
                UIMenu(options: .displayInline, children: self.actionsForProfile(accountID: accountID, source: .view(cell))),
            ])
        }
    }
    
    func collectionView(_ collectionView: UICollectionView, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: any UIContextMenuInteractionCommitAnimating) {
        MenuPreviewHelper.willPerformPreviewAction(animator: animator, presenter: self)
    }
}

extension FollowRequestNotificationViewController: UICollectionViewDragDelegate {
    func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: any UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
        let provider = NSItemProvider(object: notification.account.url as NSURL)
        let activity = UserActivityManager.showProfileActivity(id: notification.account.id, accountID: mastodonController.accountInfo!.id)
        activity.displaysAuxiliaryScene = true
        provider.registerObject(activity, visibility: .all)
        return [UIDragItem(itemProvider: provider)]
    }
}

extension FollowRequestNotificationViewController: TuskerNavigationDelegate {
    var apiController: MastodonController! { mastodonController }
}

extension FollowRequestNotificationViewController: MenuActionProvider {
}

extension FollowRequestNotificationViewController: StatusBarTappableViewController {
    func handleStatusBarTapped(xPosition: CGFloat) -> StatusBarTapActionResult {
        collectionView.scrollToTop()
        return .stop
    }
}