FRCDatasource

import UIKit
import CoreData

class FRCTableViewDataSource: NSObject, UITableViewDataSource {
    private unowned let fetchedResultsController: NSFetchedResultsController<NSFetchRequestResult>
    let configureCell: (UITableViewCell, IndexPath)-> ()

    init(fetchController: NSFetchedResultsController<NSFetchRequestResult>, configureBlock: @escaping (UITableViewCell, IndexPath)-> ()) {
        self.fetchedResultsController = fetchController
        self.configureCell = configureBlock
        super.init()
    }
    
    func numberOfSections(in tableView: UITableView) -> Int {
        return self.fetchedResultsController.sections?.count ?? 0
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        let sectionInfo = self.fetchedResultsController.sections![section]
        return sectionInfo.numberOfObjects
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell")
        self.configureCell(cell!, indexPath)
        
        return cell!
    }
    
    func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            let object = self.fetchedResultsController.object(at: indexPath) as! Deletable
            
            let confirmAlert = UIAlertController(alertType: AlertType.confirmationAlert(confirmationBlock: {
                
                object.delete({ result in
                    switch result {
                    case .success:
                        print("\(type(of: object)) deleted")
                        tableView.reloadSectionIndexTitles()
                    default: break
                    }
                })
                
            }))
            confirmAlert.show()
        }

    }
}