/// <summary>
/// Enumerates all scripts in the the container, and execute the
/// scripts that have the highest reference count first.
/// </summary>
protected void ExecuteScripts()
{
foreach (JistScript script in scriptContainer.Scripts.OrderByDescending(i => i.ReferenceCount))
{
try {
ExecuteScript(script);
RaisePercentChangedEvent("Execute");
} catch (Exception ex) {
ScriptLog.ErrorFormat(script.FilePathOrUri, "Execution error: " + ex.Message);
}
}
}
/// <summary>
/// Executes a script, and returns it's completion value.
/// </summary>
public JsValue ExecuteScript(JistScript script)
{
if (script == null || string.IsNullOrEmpty(script.Script) == true)
{
return(JsValue.Undefined);
}
try {
return(jsEngine.Execute(script.Script).GetCompletionValue());
} catch (Exception ex) {
ScriptLog.ErrorFormat(script.FilePathOrUri, "Execution error: " + ex.Message);
return(JsValue.Undefined);
}
}
/// <summary>
/// Loads a script from file into a reference-counted object, and inserts it into
/// the script container.
///
/// Scripts are /not/ executed by the javascript engine at this point.
/// </summary>
public JistScript LoadScript(string ScriptPath, bool IncreaseRefCount = true)
{
JistScript content;
/*
* if this script has already been called for, return the called object
* with an incremented ref count
*/
if (scriptContainer.Scripts.Count(i =>
i.FilePathOrUri.Equals(ScriptPath, StringComparison.InvariantCultureIgnoreCase)) > 0)
{
content = scriptContainer.Scripts.FirstOrDefault(i =>
i.FilePathOrUri.Equals(ScriptPath, StringComparison.InvariantCultureIgnoreCase));
if (IncreaseRefCount)
{
content.ReferenceCount++;
}
return(null);
}
content = new JistScript();
content.FilePathOrUri = ScriptPath;
content.ReferenceCount = 1;
try
{
content.Script = File.ReadAllText(Path.Combine(scriptsDir, content.FilePathOrUri));
}
catch (Exception ex)
{
ScriptLog.ErrorFormat("engine", "Cannot load {0}: {1}", ScriptPath, ex.Message);
return(null);
}
/*
* Script must be added to the content list before preprocessing
* this is to prevent cyclic references between @imports, used as an include guard
*/
scriptContainer.PreprocessScript(content);
scriptContainer.Scripts.Add(content);
return(content);
}
/// <summary>
/// Creates Javascript function delegates for the type specified, and
/// optionally by the object instance.
///
/// Instance may be null, however only static methods will be regarded
/// in this manner, since there is no 'this' pointer.
/// </summary>
public void CreateScriptFunctions(Type type, object instance)
{
Delegate functionDelegate = null;
Type delegateSignature = null;
string functionName = null;
JavascriptFunctionAttribute jsAttribute = null;
/*
* If the class provides functionality for scripts,
* add it into the providedpackages array.
*/
foreach (JavascriptProvidesAttribute attrib in type.GetCustomAttributes(true).OfType <JavascriptProvidesAttribute>())
{
if (!providedPackages.Contains(attrib.PackageName))
{
providedPackages.Add(attrib.PackageName);
}
}
/*
* look for JS methods in the type
*/
foreach (var jsFunction in type.GetMethods().Where(i => i.GetCustomAttributes(true).OfType <JavascriptFunctionAttribute>().Any()))
{
if (instance == null && jsFunction.IsStatic == false ||
(jsAttribute = jsFunction.GetCustomAttributes(true).OfType <JavascriptFunctionAttribute>().FirstOrDefault()) == null)
{
continue;
}
foreach (string func in jsAttribute.FunctionNames)
{
functionName = func ?? jsFunction.Name;
try
{
/*
* A delegate signature type matching every single parameter type,
* and the return type must be appended as the very last item
* in the array.
*/
delegateSignature = Expression.GetDelegateType(jsFunction.GetParameters().Select(i => i.ParameterType)
.Concat(new[] { jsFunction.ReturnType }).ToArray());
if (instance != null)
{
functionDelegate = Delegate.CreateDelegate(delegateSignature, instance, jsFunction);
}
else
{
functionDelegate = Delegate.CreateDelegate(delegateSignature, jsFunction);
}
lock (syncRoot)
jsEngine.SetValue(functionName, functionDelegate);
}
catch (Exception ex)
{
ScriptLog.ErrorFormat("engine", "Error whilst creating javascript function for {0}: {1}",
functionName, ex.ToString());
continue;
}
}
}
}
