SvgImageElement.cs :  » GUI » SharpVectorGraphics » SharpVectors » Dom » Svg » C# / CSharp Open Source

using System;
using System.IO;
using System.Net;
using System.Xml;
using System.Globalization;
using System.Diagnostics;
using System.Text.RegularExpressions;
using System.Drawing;
using System.Drawing.Drawing2D;

using SharpVectors.Net;

#if TEST 
using NUnit.Framework;
#endif

namespace SharpVectors.Dom.Svg{
  public class SvgImageElement : SvgTransformableElement, ISvgImageElement
  {
    #region Constructors
    internal SvgImageElement(string prefix, string localname, string ns, SvgDocument doc) : base(prefix, localname, ns, doc) 
    {
      svgExternalResourcesRequired = new SvgExternalResourcesRequired(this);
      svgTests = new SvgTests(this);
      svgURIReference = new SvgURIReference(this);
      svgFitToViewBox = new SvgFitToViewBox(this);
    }
    #endregion

    #region Implementation of ISvgImageElement
    private ISvgAnimatedLength width;
    public ISvgAnimatedLength Width
    {
      get
      {
        if(width == null)
        {
          width = new SvgAnimatedLength(this, "width", SvgLengthDirection.Horizontal, "0");
        }
        return width;
      }
    }
      
    private ISvgAnimatedLength height;
    public ISvgAnimatedLength Height
    {
      get
      {
        if(height == null)
        {
          height = new SvgAnimatedLength(this, "height", SvgLengthDirection.Vertical, "0");
        }
        return height;
      }
        
    }
      
    private ISvgAnimatedLength x;
    public ISvgAnimatedLength X
    {
      get
      {
        if(x == null)
        {
          x = new SvgAnimatedLength(this, "x", SvgLengthDirection.Horizontal, "0");
        }
        return x;
      }
        
    }

    private ISvgAnimatedLength y;
    public ISvgAnimatedLength Y
    {
      get
      {
        if(y == null)
        {
          y = new SvgAnimatedLength(this, "y", SvgLengthDirection.Vertical, "0");
        }
        return y;
      }
        
    }
    #endregion

    #region Implementation of ISvgURIReference
    private SvgURIReference svgURIReference;
    public ISvgAnimatedString Href
    {
      get
      {
        return svgURIReference.Href;
      }
    }

    public XmlElement ReferencedElement
    {
      get
      {
        return svgURIReference.ReferencedNode as XmlElement;
      }
    }
    #endregion

    #region Implementation of ISvgFitToViewBox
    private SvgFitToViewBox svgFitToViewBox;
    public ISvgAnimatedPreserveAspectRatio PreserveAspectRatio
    {
      get
      {
        return svgFitToViewBox.PreserveAspectRatio;
      }
    }
    #endregion

    #region Implementation of ISvgImageElement from SVG 1.2
    public SvgDocument GetImageDocument()
    {
            SvgWindow window = SvgWindow;
      if(window == null)
      {
        return null;
      }
      else
      {
                return (SvgDocument)window.Document;
      }
    }

    #endregion

    #region Public properties
    public SvgRect CalulatedViewbox
    {
      get
      {
        SvgRect viewBox;

        if ( IsSvgImage )
        {
                    SvgDocument doc = GetImageDocument();
          SvgSvgElement outerSvg = (SvgSvgElement)doc.DocumentElement;

          if ( outerSvg.HasAttribute("viewBox") )
          {
            viewBox = (SvgRect)outerSvg.ViewBox.AnimVal;
          }
          else
          {
                        viewBox = SvgRect.Empty;                        
          }
        }
        else
        {
          viewBox = new SvgRect(0,0, Bitmap.Size.Width, Bitmap.Size.Height);
        }

        return viewBox;
      }

    }

    public bool IsSvgImage
    {
      get
      {
        if(!Href.AnimVal.StartsWith("data:"))
        {
          WebResponse resource = svgURIReference.ReferencedResource;

          // local files are returning as binary/octet-stream
          // this "fix" tests the file extension for .svg and .svgz
          string name = resource.ResponseUri.ToString().ToLower(CultureInfo.InvariantCulture);
          return (
            resource.ContentType.StartsWith("image/svg+xml") ||
            name.EndsWith(".svg") ||
            name.EndsWith(".svgz") );
        }
        else
          return false;
      }
    }

    public Bitmap Bitmap
    {
      get
      {
        if(!IsSvgImage)
        {
          if(!Href.AnimVal.StartsWith("data:")) 
          {
            Stream stream = svgURIReference.ReferencedResource.GetResponseStream();
            return (Bitmap)Bitmap.FromStream(stream);
          }
          else 
          {
            string sURI = Href.AnimVal;
            int nColon = sURI.IndexOf(":");
            int nSemiColon = sURI.IndexOf(";");
            int nComma = sURI.IndexOf(",");

            string sMimeType = sURI.Substring(nColon + 1,nSemiColon - nColon - 1);

            string sContent = sURI.Substring(nComma + 1);
            byte[] bResult = Convert.FromBase64CharArray(sContent.ToCharArray(),0,sContent.Length);

            MemoryStream ms = new MemoryStream(bResult);

            return (Bitmap)Bitmap.FromStream(ms);
          }
        }
        else
        {
          return null;
        }
      }
    }

    public SvgWindow SvgWindow
    {
      get
      {
        if(IsSvgImage)
        {
          SvgWindow parentWindow = (SvgWindow)OwnerDocument.Window;

          SvgWindow wnd = new SvgWindow(parentWindow, (long)Width.AnimVal.Value, (long)Height.AnimVal.Value);

          SvgDocument doc = new SvgDocument(wnd);
          wnd.Document = doc;

          string absoluteUri = svgURIReference.AbsoluteUri;

          Stream resStream = svgURIReference.ReferencedResource.GetResponseStream();
          doc.Load(absoluteUri, resStream);

          return wnd;
        }
        else
        {
          return null;
        }
      }
    }
    #endregion

    #region Update handling    
    public override void HandleAttributeChange(XmlAttribute attribute)
    {
      if(attribute.NamespaceURI.Length == 0)
      {
        // This list may be too long to be useful...
        switch(attribute.LocalName)
        {
            // Additional attributes
          case "x":
            x = null;
            return;
          case "y":
            y = null;
            return;
          case "width":
            width = null;
            return;
          case "height":
            height = null;
            return;
        }
      
        base.HandleAttributeChange(attribute);
      } 
    }
    #endregion


    #region Implementation of ISvgExternalResourcesRequired
    private SvgExternalResourcesRequired svgExternalResourcesRequired;
    public ISvgAnimatedBoolean ExternalResourcesRequired
    {
      get
      {
        return svgExternalResourcesRequired.ExternalResourcesRequired;
      }
    }
    #endregion

    #region Implementation of ISvgTests
    private SvgTests svgTests;
    public ISvgStringList RequiredFeatures
    {
      get { return svgTests.RequiredFeatures; }
    }

    public ISvgStringList RequiredExtensions
    {
      get { return svgTests.RequiredExtensions; }
    }

    public ISvgStringList SystemLanguage
    {
      get { return svgTests.SystemLanguage; }
    }

    public bool HasExtension(string extension)
    {
      return svgTests.HasExtension(extension);
    }
        #endregion

    #region UnitTests
    #if TEST
    [TestFixture]
    public class Tests
    {
      [Test]
      public void TestDataImage()
      {
        string testData = "<?xml version='1.0'?>\n<svg xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink'><image id='theImage' width='50' height='50' xlink:href='data:image/gif;base64,R0lGODdhMAAwAPAAAAAAAP///ywAAAAAMAAwAAAC8IyPqcvt3wCcDkiLc7C0qwyGHhSWpjQu5yqmCYsapyuvUUlvONmOZtfzgFzByTB10QgxOR0TqBQejhRNzOfkVJ+5YiUqrXF5Y5lKh/DeuNcP5yLWGsEbtLiOSpa/TPg7JpJHxyendzWTBfX0cxOnKPjgBzi4diinWGdkF8kjdfnycQZXZeYGejmJlZeGl9i2icVqaNVailT6F5iJ90m6mvuTS4OK05M0vDk0Q4XUtwvKOzrcd3iq9uisF81M1OIcR7lEewwcLp7tuNNkM3uNna3F2JQFo97Vriy/Xl4/f1cf5VWzXyym7PHhhx4dbgYKAAA7'/></svg>";
        SvgWindow wnd = new SvgWindow(50, 50, null);
        SvgDocument doc = new SvgDocument(wnd);
        doc.LoadXml(testData);

        SvgImageElement imgElm = doc.GetElementById("theImage") as SvgImageElement;
        Assert.IsNotNull(imgElm);
        Assert.IsTrue(!imgElm.IsSvgImage, "IsSvgImage");

        Bitmap bmp = imgElm.Bitmap;

        Assert.AreEqual(48, bmp.Width);
        Assert.AreEqual(48, bmp.Height);
      }
    }
    #endif
    #endregion
    
  }
}