// Copyright 2015-present 650 Industries. All rights reserved.

import UIKit
import React
import EXDevMenuInterface

class DevMenuKeyCommandsInterceptor {
  /**
   Returns bool value whether the dev menu key commands are being intercepted.
   */
  static var isInstalled: Bool = false {
    willSet {
      if isInstalled != newValue {
        if newValue {
          registerKeyCommands()
        } else {
          unregisterKeyCommands()
        }
      }
    }
  }

  static private var moduleObserver: NSObjectProtocol?

  static private func registerKeyCommands() {
    addModuleObserver()

    guard let commands = RCTKeyCommands.sharedInstance() else {
      return
    }

    commands.registerKeyCommand(
      withInput: "d",
      modifierFlags: .command,
      action: { _ in DevMenuManager.shared.toggleMenu() }
    )

    commands.registerKeyCommand(
      withInput: "d",
      modifierFlags: .control,
      action: { _ in DevMenuManager.shared.toggleMenu() }
    )

    commands.registerKeyCommand(
      withInput: "r",
      modifierFlags: [],
      action: { _ in
        DevMenuManager.shared.reload()
      }
    )

    commands.registerKeyCommand(
      withInput: "i",
      modifierFlags: .command,
      action: { _ in
        DevMenuManager.shared.toggleInspector()
      }
    )

    commands.registerKeyCommand(
      withInput: "p",
      modifierFlags: .command,
      action: { _ in
        DevMenuManager.shared.togglePerformanceMonitor()
      }
    )
  }

  static private func unregisterKeyCommands() {
    guard let commands = RCTKeyCommands.sharedInstance() else {
      return
    }

    commands.unregisterKeyCommand(withInput: "d", modifierFlags: .command)
    commands.unregisterKeyCommand(withInput: "d", modifierFlags: .control)
    commands.unregisterKeyCommand(withInput: "r", modifierFlags: [])
    commands.unregisterKeyCommand(withInput: "r", modifierFlags: .command)
    commands.unregisterKeyCommand(withInput: "i", modifierFlags: .command)
    commands.unregisterKeyCommand(withInput: "p", modifierFlags: .command)

    removeModuleObserver()
  }

  static private func refreshKeyCommands() {
    guard isInstalled else {
      return
    }

    RCTExecuteOnMainQueue {
      unregisterKeyCommands()
      registerKeyCommands()
    }
  }

  static private func addModuleObserver() {
    guard moduleObserver == nil else {
      return
    }

    moduleObserver = NotificationCenter.default.addObserver(
      forName: NSNotification.Name.RCTDidInitializeModule,
      object: nil,
      queue: .main
    ) { notification in
      if (notification.userInfo?["module"] as? RCTDevMenu) != nil {
        refreshKeyCommands()
      }
    }
  }

  static private func removeModuleObserver() {
    let center = NotificationCenter.default
    if let moduleObserver {
      center.removeObserver(moduleObserver)
      self.moduleObserver = nil
    }
  }
}