/// <summary>
/// Computes the declarations for the given element in the specified window.
/// </summary>
/// <param name="window">The context of the element.</param>
/// <param name="element">The element that is questioned.</param>
/// <returns>The style declaration containing all the declarations.</returns>
public static CSSStyleDeclaration ComputeDeclarations(this IWindow window, IElement element)
{
var bag = new CssPropertyBag();
foreach (var stylesheet in window.Document.StyleSheets)
{
var sheet = stylesheet as CSSStyleSheet;
if (sheet != null && !stylesheet.IsDisabled && stylesheet.Media.Validate(window))
{
var rules = (CSSRuleList)sheet.Rules;
rules.ComputeStyle(bag, window, element);
}
}
var htmlElement = element as HTMLElement;
if (htmlElement != null)
{
bag.ExtendWith(htmlElement.Style, Priority.Inline);
}
bag.InheritFrom(element, window);
return(new CSSStyleDeclaration(bag));
}
/// <summary>
/// Extends the given bag with the set properties of the specified
/// styling declaration.
/// </summary>
/// <param name="bag">The bag to modify.</param>
/// <param name="styling">The styling properties to use.</param>
/// <param name="priority">Sets the priority of the new properties.</param>
public static void ExtendWith(this CssPropertyBag bag, CSSStyleDeclaration styling, Priority priority)
{
foreach (var property in styling.Declarations)
{
bag.TryUpdate(property, priority);
}
}
/// <summary>
/// Inherits the unspecified properties from the element's parents.
/// </summary>
/// <param name="bag">The bag to modify.</param>
/// <param name="element">The element that has unresolved properties.</param>
/// <param name="window">The associated window object.</param>
public static void InheritFrom(this CssPropertyBag bag, IElement element, IWindow window)
{
var parent = element.ParentElement;
if (parent != null)
{
var styling = window.ComputeDeclarations(parent);
foreach (var property in styling.Declarations)
{
var styleProperty = bag[property.Name];
if (styleProperty == null || styleProperty.IsInherited)
{
bag.TryUpdate(property);
}
}
}
}
internal override void ComputeStyle(CssPropertyBag style, IWindow window, IElement element)
{
foreach (var rule in _rules.List)
rule.ComputeStyle(style, window, element);
}
/// <summary>
/// Computes the style for the given element within the specified window
/// context. Writes the properties into the specified style declaration.
/// </summary>
/// <param name="style">The declaration that is used.</param>
/// <param name="window">The given window context.</param>
/// <param name="element">The element that is computed.</param>
internal virtual void ComputeStyle(CssPropertyBag style, IWindow window, IElement element)
{
//By default nothing gets computed.
}
