using AngleSharp.Extensions; using System.Collections; using System.Collections.Generic; using System.Linq; namespace AngleSharp.Dom.Css { internal sealed class CssRuleList : ICssRuleList, IEnumerable<ICssRule>, IEnumerable { private readonly CssNode _parent; public CssRule this[int index] { get { return Nodes.GetItemByIndex(index); } } ICssRule ICssRuleList.this[int index] { get { return this[index]; } } public bool HasDeclarativeRules => Nodes.Any((CssRule m) => IsDeclarativeRule(m)); public IEnumerable<CssRule> Nodes => _parent.Children.OfType<CssRule>(); public int Length => Nodes.Count(); internal CssRuleList(CssNode parent) { _parent = parent; } internal void RemoveAt(int index) { if (index < 0 || index >= Length) throw new DomException(DomError.IndexSizeError); CssRule cssRule = this[index]; if (cssRule.Type == CssRuleType.Namespace && HasDeclarativeRules) throw new DomException(DomError.InvalidState); Remove(cssRule); } internal void Remove(CssRule rule) { if (rule != null) _parent.RemoveChild(rule); } internal void Insert(int index, CssRule rule) { if (rule == null) throw new DomException(DomError.Syntax); if (rule.Type == CssRuleType.Charset) throw new DomException(DomError.Syntax); if (index > Length || index < 0) throw new DomException(DomError.IndexSizeError); if (rule.Type == CssRuleType.Namespace && HasDeclarativeRules) throw new DomException(DomError.InvalidState); if (index == Length) _parent.AppendChild(rule); else _parent.InsertBefore(this[index], rule); } internal void Add(CssRule rule) { if (rule != null) _parent.AppendChild(rule); } public IEnumerator<ICssRule> GetEnumerator() { return Nodes.GetEnumerator(); } IEnumerator IEnumerable.GetEnumerator() { return GetEnumerator(); } private static bool IsDeclarativeRule(CssRule rule) { CssRuleType type = rule.Type; if (type != CssRuleType.Import && type != CssRuleType.Charset) return type != CssRuleType.Namespace; return false; } } }