#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Collections;
using System.Text;
using System.IO;
#if GDI
using System.Drawing;
using System.Drawing.Imaging;
#endif
#if WPF
using System.Windows.Media;
#endif
using PdfSharp.Drawing;
using PdfSharp.Fonts.TrueType;
using PdfSharp.Internal;
using PdfSharp.Pdf.Internal;

namespace PdfSharp.Pdf.Advanced
{
  /// <summary>
  /// Represents a tiling pattern dictionary.
  /// </summary>
  public sealed class PdfTilingPattern : PdfDictionaryWithContentStream
  {
    /// <summary>
    /// Initializes a new instance of the <see cref="PdfShadingPattern"/> class.
    /// </summary>
    public PdfTilingPattern(PdfDocument document)
      : base(document)
    {
      Elements.SetName(Keys.Type, "/Pattern");
      Elements[Keys.PatternType] = new PdfInteger(1);
    }

    ///// <summary>
    ///// Setups the shading pattern from the specified brush.
    ///// </summary>
    //public void SetupFromBrush(XLinearGradientBrush brush, XMatrix matrix)
    //{
    //  if (brush == null)
    //    throw new ArgumentNullException("brush");

    //  PdfShading shading = new PdfShading(this.document);
    //  shading.SetupFromBrush(brush);
    //  Elements[Keys.Shading] = shading;
    //  Elements[Keys.Matrix] = new PdfLiteral("[" + PdfEncoders.ToString(matrix) + "]");
    //}

    /// <summary>
    /// Common keys for all streams.
    /// </summary>
    internal sealed new class Keys : PdfDictionaryWithContentStream.Keys
    {
      /// <summary>
      /// (Optional) The type of PDF object that this dictionary describes; if present,
      /// must be Pattern for a pattern dictionary.
      /// </summary>
      [KeyInfo(KeyType.Name | KeyType.Required)]
      public const string Type = "/Type";

      /// <summary>
      /// (Required) A code identifying the type of pattern that this dictionary describes;
      /// must be 1 for a tiling pattern.
      /// </summary>
      [KeyInfo(KeyType.Integer | KeyType.Required)]
      public const string PatternType = "/PatternType";

      /// <summary>
      /// (Required) A code that determines how the color of the pattern cell is to be specified:
      /// 1: Colored tiling pattern. The pattern’s content stream specifies the colors used to 
      /// paint the pattern cell. When the content stream begins execution, the current color
      /// is the one that was initially in effect in the pattern’s parent content stream.
      /// 2: Uncolored tiling pattern. The pattern’s content stream does not specify any color
      /// information. Instead, the entire pattern cell is painted with a separately specified color
      /// each time the pattern is used. Essentially, the content stream describes a stencil
      /// through which the current color is to be poured. The content stream must not invoke
      /// operators that specify colors or other color-related parameters in the graphics state;
      /// otherwise, an error occurs. The content stream may paint an image mask, however,
      /// since it does not specify any color information.
      /// </summary>
      [KeyInfo(KeyType.Integer | KeyType.Required)]
      public const string PaintType = "/PaintType";

      /// <summary>
      /// (Required) A code that controls adjustments to the spacing of tiles relative to the device
      /// pixel grid:
      /// 1: Constant spacing. Pattern cells are spaced consistently—that is, by a multiple of a
      /// device pixel. To achieve this, the application may need to distort the pattern cell slightly
      /// by making small adjustments to XStep, YStep, and the transformation matrix. The amount
      /// of distortion does not exceed 1 device pixel.
      /// 2: No distortion. The pattern cell is not distorted, but the spacing between pattern cells
      /// may vary by as much as 1 device pixel, both horizontally and vertically, when the pattern
      /// is painted. This achieves the spacing requested by XStep and YStep on average but not
      /// necessarily for each individual pattern cell.
      /// 3: Constant spacing and faster tiling. Pattern cells are spaced consistently as in tiling
      /// type 1 but with additional distortion permitted to enable a more efficient implementation. 
      /// </summary>
      [KeyInfo(KeyType.Integer | KeyType.Required)]
      public const string TilingType = "/TilingType";
      
      /// <summary>
      /// (Required) An array of four numbers in the pattern coordinate system giving the
      /// coordinates of the left, bottom, right, and top edges, respectively, of the pattern
      /// cell’s bounding box. These boundaries are used to clip the pattern cell.
      /// </summary>
      [KeyInfo(KeyType.Rectangle | KeyType.Optional)]
      public const string BBox = "/BBox";

      /// <summary>
      /// (Required) The desired horizontal spacing between pattern cells, measured in the
      /// pattern coordinate system.
      /// </summary>
      [KeyInfo(KeyType.Real | KeyType.Required)]
      public const string XStep = "/XStep";

      /// <summary>
      /// (Required) The desired vertical spacing between pattern cells, measured in the pattern
      /// coordinate system. Note that XStep and YStep may differ from the dimensions of the
      /// pattern cell implied by the BBox entry. This allows tiling with irregularly shaped figures.
      /// XStep and YStep may be either positive or negative but not zero.
      /// </summary>
      [KeyInfo(KeyType.Real | KeyType.Required)]
      public const string YStep = "/YStep";

      /// <summary>
      /// (Required) A resource dictionary containing all of the named resources required by
      /// the pattern’s content stream (see Section 3.7.2, “Resource Dictionaries”).
      /// </summary>
      [KeyInfo(KeyType.Dictionary | KeyType.Required)]
      public new const string Resources = "/Resources";

      /// <summary>
      /// (Optional) An array of six numbers specifying the pattern matrix.
      /// Default value: the identity matrix [1 0 0 1 0 0].
      /// </summary>
      [KeyInfo(KeyType.Array | KeyType.Optional)]
      public const string Matrix = "/Matrix";

      /// <summary>
      /// Gets the KeysMeta for these keys.
      /// </summary>
      internal static DictionaryMeta Meta
      {
        get
        {
          if (Keys.meta == null)
            Keys.meta = CreateMeta(typeof(Keys));
          return Keys.meta;
        }
      }
      static DictionaryMeta meta;
    }

    /// <summary>
    /// Gets the KeysMeta of this dictionary type.
    /// </summary>
    internal override DictionaryMeta Meta
    {
      get { return Keys.Meta; }
    }
  }
}
