using System;

namespace Netron.Diagramming.Core.Layout.Force {
  /// <summary>
  /// Represents a point particle in a force simulation, maintaining values for
  /// mass, forces, velocity, and position.
  /// </summary>
  public class ForceItem : ICloneable {
    #region Fields
    /// <summary>
    /// Temporary variables for Runge-Kutta integration 
    /// </summary>
    private float[,] l;
    /// <summary>
    /// The mass value of this ForceItem. 
    /// </summary>
    private float mass;
    /// <summary> The values of the forces acting on this ForceItem. 
    /// </summary>
    private float[] force;
    /// <summary>
    /// The velocity values of this ForceItem. 
    /// </summary>
    private float[] velocity;
    /// <summary> 
    /// The location values of this ForceItem. 
    /// </summary>
    private float[] location;
    /// <summary> 
    /// The previous location values of this ForceItem.
    /// /// </summary>
    private float[] plocation;
    /// <summary> 
    /// Temporary variables for Runge-Kutta integration
    /// /// </summary>
    private float[,] k;
    #endregion

    #region Properties
    /// <summary>
    /// Gets or sets the temporary Runge-Kutta integration value.
    /// </summary>
    /// <value>The runge kutta temp1.</value>
    public float[,] RungeKuttaTemp1 {
      get { return k; }
      set { k = value; }
    }


    /// <summary>
    /// Gets or sets the temporary Runge-Kutta integration value.
    /// </summary>
    /// <value>The runge kutta temp2.</value>
    public float[,] RungeKuttaTemp2 {
      get { return l; }
      set { l = value; }
    }
    /// <summary>
    /// Gets or sets the mass.
    /// </summary>
    /// <value>The mass.</value>
    public float Mass {
      get { return mass; }
      set { mass = value; }
    }
    /// <summary>
    /// Gets or sets the force.
    /// </summary>
    /// <value>The force.</value>
    public float[] Force {
      get { return force; }
      set { force = value; }
    }
    /// <summary>
    /// Gets or sets the velocity.
    /// </summary>
    /// <value>The velocity.</value>
    public float[] Velocity {
      get { return velocity; }
      set { velocity = value; }
    }
    /// <summary>
    /// Gets or sets the location.
    /// </summary>
    /// <value>The location.</value>
    public float[] Location {
      get { return location; }
      set { location = value; }
    }
    /// <summary>
    /// Gets or sets the previous location.
    /// </summary>
    /// <value>The previous location.</value>
    public float[] PreviousLocation {
      get { return plocation; }
      set { plocation = value; }
    }


    #endregion

    #region Constructor
    /// <summary>
    /// Create a new ForceItem.
    /// </summary>
    public ForceItem() {
      mass = 1.0f;
      force = new float[] { 0.0F, 0.0F };
      velocity = new float[] { 0.0F, 0.0F };
      location = new float[] { 0.0F, 0.0F };
      plocation = new float[] { 0.0F, 0.0F };
      k = new float[4, 2];
      l = new float[4, 2];
    }

    #endregion



    #region Methods
    /// <summary>
    /// Checks a ForceItem to make sure its values are all valid numbers(i.e., not NaNs).
    /// </summary>
    /// <param name="item">The item to check.</param>
    /// <returns>
    /// 	<c>true</c> if the specified item is valid; otherwise, <c>false</c>.
    /// </returns>
    public static bool isValid(ForceItem item) {
      return
        !(float.IsNaN(item.location[0]) || float.IsNaN(item.location[1]) ||
           float.IsNaN(item.plocation[0]) || float.IsNaN(item.plocation[1]) ||
           float.IsNaN(item.velocity[0]) || float.IsNaN(item.velocity[1]) ||
           float.IsNaN(item.force[0]) || float.IsNaN(item.force[1]));
    }


    /// <summary>
    /// Creates a new object that is a copy of the current instance.
    /// </summary>
    /// <returns>
    /// A new object that is a copy of this instance.
    /// </returns>
    public object Clone() {
      //ForceItem item = new ForceItem();
      //item.mass = this.mass;
      //Array.Copy(force, 0, item.force, 0, 2);
      //Array.Copy(velocity, 0, item.velocity, 0, 2);
      //Array.Copy(location, 0, item.location, 0, 2);
      //Array.Copy(plocation, 0, item.plocation, 0, 2);
      //for (int i = 0; i < k.Length; ++i)
      //{
      //    Array.Copy(k[i,], 0, item.k[i,], 0, 2);
      //    Array.Copy(l[i], 0, item.l[i], 0, 2);
      //    Array
      //}
      //return item;
      throw new NotImplementedException("Do you really need this feature?");
    }
    #endregion
  }
}