/**
 * TrackerMap
 * Copyright (C) 2021-2022  Iván Ávalos <avalos@disroot.org>, Henoch Ojeda <imhenoch@protonmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
import Foundation
import shared

// Source: https://www.kiloloco.com/articles/004-dependency-injection-via-property-wrappers/
// Source: https://medium.com/swlh/c1f02f06cd51
class Resolver {

    private var storage = [String: (Resolver) -> Injectable]()
    
    static let shared = Resolver()
    private init() {}
    
    func add(_ type: Injectable.Type, factory: @escaping (Resolver) -> Injectable) {
        let key = String(reflecting: type.self)
        storage[key] = factory
    }
    
    func resolve<T: Injectable>() -> T {
        let key = String(reflecting: T.self)
        
        guard let injectable = storage[key]?(self) as? T else {
            fatalError("\(key) has not been added as an injectable object.")
        }
        
        return injectable
    }

}