//
//  AsyncResultOperation.swift
//  https://github.com/Pimine/PimineSDK
//
//  This code is distributed under the terms and conditions of the MIT license.
//  Copyright (c) 2020 Pimine
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included in all
//  copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
//  SOFTWARE.

import Foundation

open class AsyncResultOperation<Success, Failure>: AsyncOperation where Failure: Error {

    // MARK: Properties
    
    private(set) public var result: Result<Success, Failure>?

    // MARK: Methods
    
    final override public func finish() {
        guard !isCancelled else { return super.finish() }
        fatalError("Make use of finish(with:) instead to ensure a result")
    }

    public func finish(with result: Result<Success, Failure>) {
        self.result = result
        super.finish()
    }

    override open func cancel() {
        fatalError("Make use of cancel(with:) instead to ensure a result")
    }

    public func cancel(with error: Failure) {
        self.result = .failure(error)
        super.cancel()
    }
}

// MARK: - ChainedOperationOutputProviding

extension AsyncResultOperation: ChainedOperationOutputProviding {
    var output: Any? {
        try? result?.get()
    }
}
