using System;

using UnityEngine;

using Framework.Services;

namespace Framework.State {

  /// <summary>Can be implemented by a component to make it user-controllable</summary>
  public class PlayerControllable : ScriptComponent, IControllable {

    /// <summary>Triggered when control of the game object is being taken</summary>
    public event Action<int> ControlTaken;
    /// <summary>Triggered when control of the game object has been released</summary>
    public event Action<int> ControlReleased;

    /// <summary>Initialized a new player controllable</summary>
    public PlayerControllable() {
      this.controllingPlayerIndex = -1;
    }

    /// <summary>Called when the player takes control of the controllable</summary>
    /// <param name="playerIndex">Index of the player that has taken control</param>
    public void OnTakeControl(int playerIndex) {
      if(this.controllingPlayerIndex != -1) {
        Debug.LogError(
          "Player " + playerIndex.ToString() + " tried to take control of '" +
          gameObject.name + "' but player " + this.controllingPlayerIndex.ToString() +
          "already has control!"
        );
        return;
      }

      this.controllingPlayerIndex = playerIndex;
      if(ControlTaken != null) {
        ControlTaken(playerIndex);
      }

      Debug.Log("Player " + playerIndex.ToString() + " is now in control of " + gameObject.name);
    }

    /// <summary>Called when the player releases control o the controllable</summary>
    /// <param name="playerIndex">Index of the player that has released control</param>
    public void OnReleaseControl(int playerIndex) {
      if(this.controllingPlayerIndex == -1) {
        return; // Double-frees are a sign of shitty coding but not an error
      }
      
      if(this.controllingPlayerIndex != playerIndex) {
        Debug.LogError(
          "Player " + playerIndex.ToString() + " tried to yield control of '" +
          gameObject.name + "' but it is being controlled by player " +
          this.controllingPlayerIndex.ToString()
        );
        return;
      }

      this.controllingPlayerIndex = -1;
      if(ControlReleased != null) {
        ControlReleased(playerIndex);
      }

      Debug.Log("Player " + playerIndex.ToString() + " released control of " + gameObject.name);
    }

    /// <summary>Index of the currently player currently in control, -1 for none</summary>
    public int ControllingPlayerIndex {
      get { return this.controllingPlayerIndex; }
    }

    /// <summary>Index of the player currently in control of this controllable</summary>
    private int controllingPlayerIndex;

  }

} // namespace Framework.State