using System;
using System.Collections.Generic;

using UnityEngine;

namespace Framework.Input {

  /// <summary>Action to which axes and buttons on input devices can be bound</summary>
  public interface IAction {

    /// <summary>Unique name of the action</summary>
    string Name { get; }

    /// <summary>Describes what purpose the action serves</summary>
    /// <remarks>
    ///   Can be displayed to the user in the key binding screen, for example,
    ///   to explain what the action does.
    /// </remarks>
    string Description { get; }

    /// <summary>Keys and buttons that have been bound to this action</summary>
    /// <remarks>
    ///   Simply adding a key or button to this collection will bind it.
    /// </remarks>
    ICollection<KeyCode> BoundKeys { get; }

    /// <summary>Joystick axes that have been bound to this action</summary>
    /// <remarks>
    ///   Simply adding a joystick axis to this collection will bind it.
    /// </remarks>
    ICollection<JoystickAxis> BoundJoystickAxes { get; }

    /// <summary>Whether the action is currently active</summary>
    /// <remarks>
    ///   If joystick axes are bound to this action, it becomes active when the axis
    ///   goes over 67% and inactive when the axis goes under 33%. This prevents
    ///   flickering of the input between active/inactive if the axis has noise.
    /// </remarks>
    bool IsActive { get; }

    /// <summary>Whether the action has become active since it was last checked</summary>
    /// <remarks>
    ///   This goes high as soon as the action becomes active and is only reset
    ///   in the next update phase after it has been queried at least once.
    /// </remarks>
    bool WasTriggered { get; }

    /// <summary>Analogue state of the action</summary>
    /// <remarks>
    ///   If keys or buttons are bound to the action, these will immediately result
    ///   in a value of 1.0. Analogue axes will result in v
    /// </remarks>
    float State { get; }

    /// <summary>Removes all bound keys, buttons and axes from the action</summary>
    void RemoveAllBindings();

    /// <summary>Whether the action is no longer part of the input mapper</summary>
    /// <remarks>
    ///   <para>
    ///     You only need to bother with this if two conditions apply: you save
    ///     references to <see cref="IAction" /> instances and remove actions from
    ///     the input mapper through <see cref="Clear" /> or other means. In that
    ///     particular case, you will have actions that no longer belong to
    ///     the input mapper and thus will no longer get updated:
    ///   </para>
    ///   <para>
    ///     <example>
    ///       <code>
    ///         IAction action = myInputMapper.CreateAction("Jump");
    ///         myInputMapper.Actions.Clear(); // Remove all actions
    ///
    ///         bool isAbandoned = action.IsAbandoned; // true
    ///       </code>
    ///     </example>
    ///   </para>
    /// </remarks>
    bool IsAbandoned { get; }

  }

} // namespace Framework.Input