#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2007 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 PdfSharp.Pdf.Internal;

namespace PdfSharp.Pdf.AcroForms
{
  /// <summary>
  /// Represents a interactive form (or AcroForm), a collection of fields for 
  /// gathering information interactively from the user.
  /// </summary>
  public sealed class PdfAcroForm : PdfDictionary
  {
    /// <summary>
    /// Initializes a new instance of AcroForm.
    /// </summary>
    internal PdfAcroForm(PdfDocument document) : base(document)
    {
      this.document = document;
    }

    PdfAcroForm(PdfDictionary dictionary) : base(dictionary)
    {
    }

    public PdfAcroField.PdfAcroFieldCollection Fields
    {
      get
      {
        if (this.fields == null)
        {
          object o = Elements.GetValue(Keys.Fields, VCF.CreateIndirect);
          this.fields = (PdfAcroField.PdfAcroFieldCollection)o;
        }
        return this.fields;
      }
    }
    PdfAcroField.PdfAcroFieldCollection fields;

    /// <summary>
    /// Predefined keys of this dictionary. 
    /// The description comes from PDF 1.4 Reference.
    /// </summary>
    public sealed class Keys : KeysBase
    {
      /// <summary>
      /// (Required) An array of references to the document’s root fields (those with
      /// no ancestors in the field hierarchy).
      /// </summary>
      [KeyInfo(KeyType.Array | KeyType.Required, typeof(PdfAcroField.PdfAcroFieldCollection))]
      public const string Fields = "/Fields";

      /// <summary>
      /// (Optional) A flag specifying whether to construct appearance streams and
      /// appearance dictionaries for all widget annotations in the document.
      /// Default value: false.
      /// </summary>
      [KeyInfo(KeyType.Boolean | KeyType.Optional)]
      public const string NeedAppearances = "/NeedAppearances";

      /// <summary>
      /// (Optional; PDF 1.3) A set of flags specifying various document-level characteristics
      /// related to signature fields.
      /// Default value: 0.
      /// </summary>
      [KeyInfo("1.3", KeyType.Integer | KeyType.Optional)]
      public const string SigFlags = "/SigFlags";

      /// <summary>
      /// (Required if any fields in the document have additional-actions dictionaries
      /// containing a C entry; PDF 1.3) An array of indirect references to field dictionaries
      /// with calculation actions, defining the calculation order in which their values will 
      /// be recalculated when the value of any field changes.
      /// </summary>
      [KeyInfo(KeyType.Array)]
      public const string CO = "/CO";

      /// <summary>
      /// (Optional) A document-wide default value for the DR attribute of variable text fields.
      /// </summary>
      [KeyInfo(KeyType.Dictionary | KeyType.Optional)]
      public const string DR = "/DR";

      /// <summary>
      /// (Optional) A document-wide default value for the DA attribute of variable text fields.
      /// </summary>
      [KeyInfo(KeyType.String | KeyType.Optional)]
      public const string DA = "/DA";

      /// <summary>
      /// (Optional) A document-wide default value for the Q attribute of variable text fields.
      /// </summary>
      [KeyInfo(KeyType.Integer | KeyType.Optional)]
      public const string Q = "/Q";

      /// <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;}
    }
  }
}
