using AngleSharp.Css; using AngleSharp.Extensions; using System; using System.Collections; using System.Collections.Generic; namespace AngleSharp.Dom.Css { internal sealed class CssMedium : IEnumerable<MediaFeature>, IEnumerable, IStyleFormattable { private static readonly string[] Types = new string[4] { Keywords.Screen, Keywords.Speech, Keywords.Print, Keywords.All }; private readonly List<MediaFeature> _features; public string Type { get; set; } public bool IsExclusive { get; set; } public bool IsInverse { get; set; } public string Constraints { get { string[] array = new string[_features.Count]; for (int i = 0; i < _features.Count; i++) { array[i] = _features[i].ToCss(); } return string.Join(" and ", array); } } internal CssMedium() { _features = new List<MediaFeature>(); } public bool Validate(RenderDevice device) { if (!string.IsNullOrEmpty(Type) && Types.Contains(Type, StringComparison.Ordinal) == IsInverse) return false; if (IsInvalid(device, Keywords.Screen, RenderDevice.Kind.Screen) || IsInvalid(device, Keywords.Speech, RenderDevice.Kind.Speech) || IsInvalid(device, Keywords.Print, RenderDevice.Kind.Printer)) return false; foreach (MediaFeature feature in _features) { if (feature.Validate(device) == IsInverse) return false; } return true; } public IEnumerator<MediaFeature> GetEnumerator() { return _features.GetEnumerator(); } IEnumerator IEnumerable.GetEnumerator() { return GetEnumerator(); } internal void AddConstraint(MediaFeature feature) { _features.Add(feature); } public override bool Equals(object obj) { CssMedium cssMedium = obj as CssMedium; if (cssMedium != null && cssMedium.IsExclusive == IsExclusive && cssMedium.IsInverse == IsInverse && cssMedium.Type == Type && cssMedium._features.Count == _features.Count) { foreach (MediaFeature feature in cssMedium._features) { List<MediaFeature> features = _features; Predicate<MediaFeature> match = (MediaFeature m) => m.Name == feature.Name; MediaFeature mediaFeature = features.Find(match); if (mediaFeature == null || mediaFeature.Value != feature.Value) return false; } return true; } return false; } public override int GetHashCode() { return base.GetHashCode(); } public string ToCss() { return ToCss(CssStyleFormatter.Instance); } public string ToCss(IStyleFormatter formatter) { string[] array = new string[_features.Count]; for (int i = 0; i < _features.Count; i++) { array[i] = _features[i].ToCss(formatter); } return formatter.Medium(IsExclusive, IsInverse, Type, array); } private bool IsInvalid(RenderDevice device, string keyword, RenderDevice.Kind kind) { if (Type == keyword) return device.DeviceType == kind == IsInverse; return false; } } }