using System;
using System.Reflection;

using UnityEngine;

namespace Framework.Support {

  /// <summary>Invokes protected or private methods on MonoBehaviors</summary>
  /// <remarks>
  ///   Intended for unit testing
  /// </remarks>
  public static class MethodInvoker {

    /// <summary>
    ///   Calls the Inject() method on the specified MonoBehaviour-based object
    /// </summary>
    /// <param name="monoBehaviour">
    ///   MonoBehaviour on which Inject() will be invoked
    /// </param>
    /// <param name="arguments">
    ///   Arguments that will be passed to the Inject() method
    /// </param>
    public static void CallInject(
      this MonoBehaviour monoBehaviour, params object[] arguments
    ) {
      MethodInfo injectMethodInfo = monoBehaviour.GetType().GetMethod(
        "Inject", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public
      );
      injectMethodInfo.Invoke(monoBehaviour, arguments);
    }

    /// <summary>
    ///   Calls the Awake() method on the specified MonoBehaviour-based object
    /// </summary>
    /// <param name="monoBehaviour">
    ///   MonoBehaviour on which Awake() will be invoked
    /// </param>
    public static void CallAwake(this MonoBehaviour monoBehaviour) {
      MethodInfo awakeMethodInfo = monoBehaviour.GetType().GetMethod(
        "Awake", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public
      );
      awakeMethodInfo.Invoke(monoBehaviour, null);
    }

    /// <summary>
    ///   Calls the Update() method on the specified MonoBehaviour-based object
    /// </summary>
    /// <param name="monoBehaviour">
    ///   MonoBehaviour on which Update() will be invoked
    /// </param>
    public static void CallUpdate(this MonoBehaviour monoBehaviour) {
      MethodInfo updateMethodInfo = monoBehaviour.GetType().GetMethod(
        "Update", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public
      );
      updateMethodInfo.Invoke(monoBehaviour, null);
    }

    /// <summary>
    ///   Calls the OnEnable() method on the specified MonoBehaviour-based object
    /// </summary>
    /// <param name="monoBehaviour">
    ///   MonoBehaviour on which OnEnable() will be invoked
    /// </param>
    public static void CallOnEnable(this MonoBehaviour monoBehaviour) {
      MethodInfo onEnableMethodInfo = monoBehaviour.GetType().GetMethod(
        "OnEnable", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public
      );
      onEnableMethodInfo.Invoke(monoBehaviour, null);
    }

    /// <summary>
    ///   Calls the OnDestroy() method on the specified MonoBehaviour-based object
    /// </summary>
    /// <param name="monoBehaviour">
    ///   MonoBehaviour on which OnDestroy() will be invoked
    /// </param>
    public static void CallOnDestroy(this MonoBehaviour monoBehaviour) {
      MethodInfo onDestroyMethodInfo = monoBehaviour.GetType().GetMethod(
        "OnDestroy", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public
      );
      onDestroyMethodInfo.Invoke(monoBehaviour, null);
    }

  }

} // namespace Framework.Support