/// <summary>
/// Initializes a new instance of the <see cref="PrioritizedStyle"/> structure.
/// </summary>
/// <param name="style">The style being applied.</param>
/// <param name="selector">The selector which caused the style to be applied.</param>
/// <param name="priority">The style's priority.</param>
/// <param name="index">The index of the style's rule set within its style sheet.</param>
public PrioritizedStyle(UvssRule style, UvssSelector selector, Int32 priority, Int32 index)
{
this.Style = style;
this.Selector = selector;
this.Priority = priority;
this.Index = index;
}
/// <summary>
/// Adds a styling rule to the prioritizer.
/// </summary>
/// <param name="uv">The Ultraviolet context.</param>
/// <param name="selector">The selector which caused this style to be considered.</param>
/// <param name="navigationExpression">The navigation expression associated with the style.</param>
/// <param name="rule">The styling rule to add to the prioritizer.</param>
/// <param name="index">The index of the rule's rule set within the style sheet.</param>
public void Add(UltravioletContext uv, UvssSelector selector, NavigationExpression?navigationExpression, UvssRule rule, Int32 index)
{
Contract.Require(uv, nameof(uv));
var key = new StyleKey(rule.CanonicalName, navigationExpression);
var priority = CalculatePriorityFromSelector(selector, rule.IsImportant);
PrioritizedStyle existing;
if (!rules.TryGetValue(key, out existing))
{
rules[key] = new PrioritizedStyle(rule, selector, priority, index);
}
else
{
var comparison = selector.ComparePriority(existing.Selector);
if (comparison == 0 && index > existing.Index)
{
comparison = 1;
}
if (comparison > 0 && (rule.IsImportant || !existing.Style.IsImportant))
{
rules[key] = new PrioritizedStyle(rule, selector, priority, index);
}
}
}