// MIT License
//
// Copyright (c) 2017-2019 MessageKit
//
// 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 MessageKit
import UIKit

@MainActor
final class MockSocket {
  // MARK: Lifecycle

  private init() { }

  // MARK: Internal

  static var shared = MockSocket()

  @discardableResult
  func connect(with senders: [MockUser]) -> Self {
    disconnect()
    connectedUsers = senders
    timer = Timer.scheduledTimer(
      timeInterval: 2.5,
      target: self,
      selector: #selector(handleTimer),
      userInfo: nil,
      repeats: true)
    return self
  }

  @discardableResult
  func disconnect() -> Self {
    timer?.invalidate()
    timer = nil
    onTypingStatusCode = nil
    onNewMessageCode = nil
    return self
  }

  @discardableResult
  func onNewMessage(code: @escaping (MockMessage) -> Void) -> Self {
    onNewMessageCode = code
    return self
  }

  @discardableResult
  func onTypingStatus(code: @escaping () -> Void) -> Self {
    onTypingStatusCode = code
    return self
  }

  // MARK: Private

  private var timer: Timer?

  private var queuedMessage: MockMessage?

  private var onNewMessageCode: ((MockMessage) -> Void)?

  private var onTypingStatusCode: (() -> Void)?

  private var connectedUsers: [MockUser] = []

  @objc
  private func handleTimer() {
    if let message = queuedMessage {
      onNewMessageCode?(message)
      queuedMessage = nil
    } else {
      let sender = connectedUsers.random()!
      let message = SampleData.shared.randomMessage(allowedSenders: [sender])
      queuedMessage = message
      onTypingStatusCode?()
    }
  }
}