using AngleSharp.Css; namespace AngleSharp.Dom.Css { internal abstract class CssProperty : ICssProperty { private readonly PropertyFlags _flags; private readonly string _name; private readonly CssStyleDeclaration _rule; private bool _important; private CssValue _value; internal CssStyleDeclaration Rule => _rule; internal bool HasValue => _value != null; internal bool CanBeHashless => _flags.HasFlag(PropertyFlags.Hashless); internal bool CanBeUnitless => _flags.HasFlag(PropertyFlags.Unitless); internal bool CanBeInherited => _flags.HasFlag(PropertyFlags.Inherited); internal bool IsShorthand => _flags.HasFlag(PropertyFlags.Shorthand); internal CssValue Value => _value ?? CssValue.Initial; public bool IsInherited { get { if (!_flags.HasFlag(PropertyFlags.Inherited) || !IsInitial) return Value.Type == CssValueType.Inherit; return true; } } public bool IsAnimatable => _flags.HasFlag(PropertyFlags.Animatable); public bool IsInitial { get { if (_value != null) return _value.Type == CssValueType.Initial; return true; } } public string Name => _name; ICssValue ICssProperty.Value { get { return Value; } } public bool IsImportant { get { return _important; } set { _important = value; } } public string CssText => Serialize(_name, SerializeValue(), _important); internal CssProperty(string name, CssStyleDeclaration rule, PropertyFlags flags = PropertyFlags.None) { _rule = rule; _name = name; _flags = flags; } internal bool TrySetValue(CssValue value) { if (value == null || value.Type == CssValueType.Inherit || value.Type == CssValueType.Initial) { Reset(); _value = value; return true; } if (IsValid(value)) { _value = value; return true; } return false; } internal virtual void Reset() { _value = null; } protected abstract object GetDefault(IElement element); protected abstract object Compute(IElement element); protected abstract bool IsValid(CssValue value); internal virtual string SerializeValue() { return Value.CssText; } internal static string Serialize(string name, string value, bool important) { return name + ": " + (value + (important ? " !important" : string.Empty) + ";"); } } }