//
//    Copyright 2023 Marc Stibane
//
//  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

@propertyWrapper
class Atomic<Value> where Value: BinaryInteger {

    private let lock: NSLock
    private var value: Value

    init(default: Value) {
        self.lock = NSLock()
        self.value = `default`
    }

    var wrappedValue: Value {
        get {
            lock.lock()
            defer { lock.unlock() }
            return value
        }
        set {
            lock.lock()
            value = newValue
            lock.unlock()
        }
    }

    var projectedValue: Atomic<Value> { self }

    @discardableResult
    func atomicIncrement() -> Value {
        lock.lock()
        defer { lock.unlock() }
        self.value += 1
        return value
    }

    @discardableResult
    func atomicAdd(_ value: Value) -> Value {
        lock.lock()
        defer { lock.unlock() }
        self.value += value
        return value
    }
}