/*

 * Copyright 2019, gRPC Authors All rights reserved.

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

import Foundation

internal class Stopwatch {

  private let dateProvider: () -> Date

  private let start: Date

  init(provider: @escaping () -> Date = { Date() }) {

    self.dateProvider = provider

    self.start = provider()

  }

  static func start() -> Stopwatch {

    return Stopwatch()

  }

  func elapsed() -> TimeInterval {

    return self.dateProvider().timeIntervalSince(self.start)

  }

  func elapsedMillis() -> Int64 {

    return Int64(self.elapsed() * 1000)

  }

}