#region CPL License
/*
Nuclex Framework
Copyright (C) 2002-2011 Nuclex Development Labs

This library is free software; you can redistribute it and/or
modify it under the terms of the IBM Common Public License as
published by the IBM Corporation; either version 1.0 of the
License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
IBM Common Public License for more details.

You should have received a copy of the IBM Common Public
License along with this library
*/
#endregion

using System;
using System.Collections.Generic;

using Microsoft.Xna.Framework;

namespace Nuclex.Game.Packing {

  /// <summary>Base class for rectangle packing algorithms</summary>
  /// <remarks>
  ///   <para>
  ///     By uniting all rectangle packers under this common base class, you can
  ///     easily switch between different algorithms to find the most efficient or
  ///     performant one for a given job.
  ///   </para>
  ///   <para>
  ///     An almost exhaustive list of packing algorithms can be found here:
  ///     http://www.csc.liv.ac.uk/~epa/surveyhtml.html
  ///   </para>
  /// </remarks>
  public abstract class RectanglePacker {

    /// <summary>Initializes a new rectangle packer</summary>
    /// <param name="packingAreaWidth">Width of the packing area</param>
    /// <param name="packingAreaHeight">Height of the packing area</param>
    protected RectanglePacker(int packingAreaWidth, int packingAreaHeight) {
      this.packingAreaWidth = packingAreaWidth;
      this.packingAreaHeight = packingAreaHeight;
    }

    /// <summary>Allocates space for a rectangle in the packing area</summary>
    /// <param name="rectangleWidth">Width of the rectangle to allocate</param>
    /// <param name="rectangleHeight">Height of the rectangle to allocate</param>
    /// <returns>The location at which the rectangle has been placed</returns>
    public virtual Point Pack(int rectangleWidth, int rectangleHeight) {
      Point point;

      if(!TryPack(rectangleWidth, rectangleHeight, out point))
        throw new OutOfSpaceException("Rectangle does not fit in packing area");

      return point;
    }

    /// <summary>Tries to allocate space for a rectangle in the packing area</summary>
    /// <param name="rectangleWidth">Width of the rectangle to allocate</param>
    /// <param name="rectangleHeight">Height of the rectangle to allocate</param>
    /// <param name="placement">Output parameter receiving the rectangle's placement</param>
    /// <returns>True if space for the rectangle could be allocated</returns>
    public abstract bool TryPack(
      int rectangleWidth, int rectangleHeight, out Point placement
    );

    /// <summary>Maximum width the packing area is allowed to have</summary>
    protected int PackingAreaWidth {
      get { return this.packingAreaWidth; }
    }

    /// <summary>Maximum height the packing area is allowed to have</summary>
    protected int PackingAreaHeight {
      get { return this.packingAreaHeight; }
    }

    /// <summary>Maximum allowed width of the packing area</summary>
    private int packingAreaWidth;
    /// <summary>Maximum allowed height of the packing area</summary>
    private int packingAreaHeight;

  }

} // namespace Nuclex.Game.Packing