Tusker/Tusker/Screens/Notifications/NotificationsTableViewController.swift

//
//  NotificationsTableViewController.swift
//  Tusker
//
//  Created by Shadowfacts on 9/2/18.
//  Copyright © 2018 Shadowfacts. All rights reserved.
//

import UIKit
import Pachyderm

class NotificationsTableViewController: UITableViewController {

    static func create() -> UIViewController {
        guard let navigationController = UIStoryboard(name: "Notifications", bundle: nil).instantiateInitialViewController() as? UINavigationController else { fatalError() }
        return navigationController
    }
    
    var notifications: [Pachyderm.Notification] = [] {
        didSet {
            DispatchQueue.main.async {
                self.tableView.reloadData()
            }
        }
    }
    
    var newer: RequestRange?
    var older: RequestRange?
    
    override func viewDidLoad() {
        super.viewDidLoad()

        // Uncomment the following line to preserve selection between presentations
        // self.clearsSelectionOnViewWillAppear = false

        // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
        // self.navigationItem.rightBarButtonItem = self.editButtonItem
        
        tableView.rowHeight = UITableView.automaticDimension
        tableView.estimatedRowHeight = 140
        
        tableView.register(UINib(nibName: "StatusTableViewCell", bundle: nil), forCellReuseIdentifier: "statusCell")
        tableView.register(UINib(nibName: "ActionNotificationTableViewCell", bundle: nil), forCellReuseIdentifier: "actionCell")
        tableView.register(UINib(nibName: "FollowNotificationTableViewCell", bundle: nil), forCellReuseIdentifier: "followCell")
        
        let request = MastodonController.shared.client.getNotifications()
        MastodonController.shared.client.run(request) { result in
            guard case let .success(notifications, pagination) = result else { fatalError() }
            self.notifications = notifications
            StatusCache.addAll(notifications.compactMap { $0.status })
            self.newer = pagination?.newer
            self.older = pagination?.older
        }
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        for cell in tableView.visibleCells {
            if let cell = cell as? PreferencesAdaptive {
                cell.updateUIForPreferences()
            }
        }
    }
    
    /*
     // MARK: - Navigation
     
     // In a storyboard-based application, you will often want to do a little preparation before navigation
     override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
     // Get the new view controller using segue.destination.
     // Pass the selected object to the new view controller.
     }
     */

    // MARK: - Table view data source

    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return notifications.count
    }

    
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let notification = notifications[indexPath.row]
        
        switch notification.kind {
        case .mention:
            guard let cell = tableView.dequeueReusableCell(withIdentifier: "statusCell", for: indexPath) as? StatusTableViewCell else { fatalError() }
            let status = notification.status!
            cell.updateUI(for: status.id)
            cell.delegate = self
            return cell
        case .favourite, .reblog:
            guard let cell = tableView.dequeueReusableCell(withIdentifier: "actionCell", for: indexPath) as? ActionNotificationTableViewCell else { fatalError() }
            cell.updateUI(for: notification)
            cell.delegate = self
            return cell
        case .follow:
            guard let cell = tableView.dequeueReusableCell(withIdentifier: "followCell", for: indexPath) as? FollowNotificationTableViewCell else { fatalError() }
            cell.updateUI(for: notification)
            cell.delegate = self
            return cell
        }
    }
 

    override func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        if indexPath.row == notifications.count - 1 {
            guard let older = older else { return }
            
            let request = MastodonController.shared.client.getNotifications(range: older)
            MastodonController.shared.client.run(request) { result in
                guard case let .success(newNotifications, pagination) = result else { fatalError() }
                self.older = pagination?.older
                self.notifications.append(contentsOf: newNotifications)
            }
        }
    }
    
    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        return tableView.cellForRow(at: indexPath) is TableViewSwipeActionProvider
    }
    
    override func tableView(_ tableView: UITableView, leadingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
        return (tableView.cellForRow(at: indexPath) as? TableViewSwipeActionProvider)?.leadingSwipeActionsConfiguration()
    }
    
    override func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
        return (tableView.cellForRow(at: indexPath) as? TableViewSwipeActionProvider)?.trailingSwipeActionsConfiguration()
    }
    
    @IBAction func refreshNotifications(_ sender: Any) {
        guard let newer = newer else { return }
        
        let request = MastodonController.shared.client.getNotifications(range: newer)
        MastodonController.shared.client.run(request) { result in
            guard case let .success(newNotifications, pagination) = result else { fatalError() }
            self.newer = pagination?.newer
            StatusCache.addAll(newNotifications.compactMap { $0.status })
            self.notifications.insert(contentsOf: newNotifications, at: 0)
            DispatchQueue.main.async {
                self.refreshControl?.endRefreshing()
                
                // maintain the current position in the list (don't scroll to top)
                self.tableView.scrollToRow(at: IndexPath(row: newNotifications.count, section: 0), at: .top, animated: false)
            }
        }
    }

}

extension NotificationsTableViewController: StatusTableViewCellDelegate {}
extension NotificationsTableViewController: LargeImageViewControllerDelegate {}