ReusableCells.swift

//
//  ReusableCells.swift
//  ella
//
//  Created by Marcos Griselli on 12/17/17.
//  Copyright © 2017 Hirsh Group LLC. All rights reserved.
//

import UIKit

protocol ReusableView: class {
    static var defaultReuseIdentifier: String { get }
}

extension ReusableView where Self: UIView {
    static var defaultReuseIdentifier: String {
        return NSStringFromClass(self)
    }
}

protocol NibLoadableView: class {
    static var nibName: String { get }
}

extension NibLoadableView where Self: UIView {
    static var nibName: String {
        return NSStringFromClass(self).components(separatedBy: ".").last!
    }
}

extension UITableView {
    
    func register<T: UITableViewCell>(_: T.Type) where T: ReusableView {
        register(T.self, forCellReuseIdentifier: T.defaultReuseIdentifier)
    }
    
    func register<T: UITableViewCell>(_: T.Type) where T: ReusableView, T: NibLoadableView {
        let bundle = Bundle(for: T.self)
        let nib = UINib(nibName: T.nibName, bundle: bundle)
        
        register(nib, forCellReuseIdentifier: T.defaultReuseIdentifier)
    }
    
    func dequeueReusableCell<T: UITableViewCell>(forIndexPath indexPath: IndexPath) -> T where T: ReusableView {
        guard let cell = dequeueReusableCell(withIdentifier: T.defaultReuseIdentifier, for: indexPath) as? T else {
            fatalError("Could not dequeue cell with identifier: \(T.defaultReuseIdentifier)")
        }
        
        return cell
    }
}

extension UICollectionView {
    
    func register<T: UICollectionViewCell>(_: T.Type) where T: ReusableView {
        register(T.self, forCellWithReuseIdentifier: T.defaultReuseIdentifier)
    }
    
    func register<T: UICollectionViewCell>(_: T.Type) where T: ReusableView, T: NibLoadableView {
        let bundle = Bundle(for: T.self)
        let nib = UINib(nibName: T.nibName, bundle: bundle)
        
        register(nib, forCellWithReuseIdentifier: T.defaultReuseIdentifier)
    }
    
    func registerHeader<T: UICollectionReusableView>(_: T.Type) where T: ReusableView {
        register(T.self,
                 forSupplementaryViewOfKind: UICollectionElementKindSectionHeader,
                 withReuseIdentifier: T.defaultReuseIdentifier)
    }
    
    func dequeueReusableCell<T: UICollectionViewCell>(forIndexPath indexPath: IndexPath) -> T where T: ReusableView {
        guard let cell = dequeueReusableCell(withReuseIdentifier: T.defaultReuseIdentifier, for: indexPath) as? T else {
            fatalError("Could not dequeue cell with identifier: \(T.defaultReuseIdentifier)")
        }
        return cell
    }
    
    func dequeueReusableHeader<T: UICollectionReusableView>(forIndexPath indexPath: IndexPath) -> T where T: ReusableView {
        guard let view = dequeueReusableSupplementaryView(ofKind: UICollectionElementKindSectionHeader,
                                                          withReuseIdentifier: T.defaultReuseIdentifier,
                                                          for: indexPath) as? T else {
                                                            fatalError("Could not dequeue view with identifier: \(T.defaultReuseIdentifier)")
        }
        return view
    }
}