Cassette.targets

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <!-- This task takes in a XDT transform file and transforms it, following any inheritance chain.
       There should be at least one base transform for this to work; otherwise just use Microsoft's
       regular TransformXml task.

       See: https://gist.github.com/1918022 -->
  <!-- EXAMPLE USAGE:
  <TransformXmlHierarchy 
    Source="some-source.xml" 
    Destination="transformed.xml"
    TaskPath="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v11.0\Web\Microsoft.Web.XmlTransform.dll"/>
  -->
  <UsingTask
    TaskName="TransformXmlHierarchy"
    TaskFactory="CodeTaskFactory"
    AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll" >
    <ParameterGroup>
      <Source Required="true" />
      <Destination Required="true" />
      <TaskPath Required="true"/>
    </ParameterGroup>
    <Task>      
      <Reference Include="System.Xml" />
      <Reference Include="Microsoft.CSharp" />
      <Using Namespace="System"/>
      <Using Namespace="System.Linq"/>
      <Using Namespace="System.IO" />
      <Using Namespace="System.Xml"/>
      <Using Namespace="System.Reflection" />
      <Code Type="Fragment" Language="cs">
<![CDATA[
if (!File.Exists(TaskPath))
    throw new Exception("Could not load publishing tasks assembly");

Assembly taskAssembly = Assembly.UnsafeLoadFrom(TaskPath);

Func<XmlDocument, string, XmlDocument> transformer = (source, transform) => 
{
  dynamic transformation = taskAssembly.CreateInstance(
    "Microsoft.Web.XmlTransform.XmlTransformation", true, BindingFlags.CreateInstance, 
    null, new object[] { transform }, null, null);
  
  if (transformation == null)
      throw new Exception("Could not create instance of XmlTransformation");

  transformation.Apply(source);

  return source;
};

Func<XmlDocument, string> getParent = (source) => 
{
  if (source == null) return null;

  // Build dependency list
  var nsmgr = new XmlNamespaceManager(source.NameTable);
  nsmgr.AddNamespace("x", source.DocumentElement.NamespaceURI);

  var attr = source.SelectSingleNode("x:package", nsmgr).Attributes["inherits"];

  return attr == null ? null : attr.Value;
};

var rootDoc = new XmlDocument();
var sources = new List<string>();
var basePath = Path.GetDirectoryName(Source);
var parent = Path.GetFileName(Source);

if (basePath == null) {
    throw new Exception("Could not find base directory of path " + Source);
}

do {
    sources.Add(parent);

    rootDoc.Load(Path.Combine(basePath, parent));

    parent = getParent(rootDoc);
    
    if (parent != null) {
        rootDoc.Load(Path.Combine(basePath, parent));
    }
} while (parent != null);

// Reverse chain
sources.Reverse();

var transformedDoc = sources.Skip(1).Aggregate(rootDoc, 
    (document, transform) => String.IsNullOrEmpty(transform) 
        ? document 
        : transformer(document, Path.Combine(basePath, transform)),
    (document) => document);

Log.LogMessage(MessageImportance.Normal, "Transformed " + Destination);

transformedDoc.Save(Destination);
]]>
      </Code>
    </Task>
  </UsingTask>
  <UsingTask TaskName="GetAssemblyInformationalVersion" 
        TaskFactory="CodeTaskFactory" 
        AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll" >
        <ParameterGroup>
            <Assembly ParameterType="System.String" Required="true" />
            <Version ParameterType="System.String" Output="true" />
        </ParameterGroup>
        <Task>
            <Using Namespace="System"/>
            <Using Namespace="System.Diagnostics"/>
            <Code Type="Fragment" Language="cs">
<![CDATA[
var version = FileVersionInfo.GetVersionInfo(Assembly);

Version = version.ProductVersion;
]]>
            </Code>
        </Task>
    </UsingTask>
</Project>