source: branches/HeuristicLab.Problems.GrammaticalOptimization/SharpVectorCss/Css/CssStyleRule.cs @ 13237

using System;
using System.Xml;
using System.Xml.XPath;
using System.Text.RegularExpressions;
using SharpVectors.Dom.Stylesheets;
using System.Collections;
using System.Collections.Generic;

namespace SharpVectors.Dom.Css
{
  /// <summary>
  /// The CSSStyleRule interface represents a single rule set in a CSS style sheet.
  /// </summary>
  /// <developer>niklas@protocol7.com</developer>
  /// <completed>80</completed>
  public class CssStyleRule : CssRule,ICssStyleRule
  {
    #region Static members

    internal static string nsPattern = @"([A-Za-z\*][A-Za-z0-9]*)?\|";
    internal static string attributeValueCheck = "(?<attname>(" + nsPattern + ")?[a-zA-Z0-9]+)\\s*(?<eqtype>[\\~\\^\\$\\*\\|]?)=\\s*(\"|\')?(?<attvalue>.*?)(\"|\')?";
    

    internal static string sSelector = "(?<ns>" + nsPattern + ")?" +
      @"(?<type>([A-Za-z\*][A-Za-z0-9]*))?" +
      @"((?<class>\.[A-Za-z][A-Za-z0-9]*)+)?" +
      @"(?<id>\#[A-Za-z][A-Za-z0-9]*)?" +
      @"((?<predicate>\[\s*(" +
      @"(?<attributecheck>(" + nsPattern + ")?[a-zA-Z0-9]+)" +
      @"|" +
      "(?<attributevaluecheck>" + attributeValueCheck + ")" +
      @")\s*\])+)?" +
      @"((?<pseudoclass>\:[a-z\-]+(\([^\)]+\))?)+)?" +
      @"(?<pseudoelements>(\:\:[a-z\-]+)+)?" +
      @"(?<seperator>(\s*(\+|\>|\~)\s*)|(\s+))?";
    private static string sStyleRule = "^((?<selector>(" + sSelector + @")+)(\s*,\s*)?)+";
    private static Regex regex = new Regex(sStyleRule);

    internal static CssRule Parse(ref string css, object parent, bool readOnly,
            IList<string> replacedStrings, CssStyleSheetType origin)
    {
      Match match = regex.Match(css);
      if(match.Success && match.Length > 0)
      {
        CssStyleRule rule = new CssStyleRule(match, parent, readOnly, replacedStrings, origin);

        css = css.Substring(match.Length);

        rule._Style = new CssStyleDeclaration(ref css, rule, readOnly, origin);

                return rule;
      }
      else
      {
        return null;
      }
    }
    #endregion

    #region Constructors

    /// <summary>
    /// The constructor for CssStyleRule
    /// </summary>
    /// <param name="match">The Regex match that found the charset rule</param>
    /// <param name="parent">The parent rule or parent stylesheet</param>
    /// <param name="readOnly">True if this instance is readonly</param>
    /// <param name="replacedStrings">An array of strings that have been replaced in the string used for matching. These needs to be put back use the DereplaceStrings method</param>
    /// <param name="origin">The type of CssStyleSheet</param>
    internal CssStyleRule(Match match, object parent, bool readOnly,
            IList<string> replacedStrings, CssStyleSheetType origin)
            : base(parent, readOnly, replacedStrings, origin)
    {
      //SelectorText = DeReplaceStrings(match.Groups["selectors"].Value.Trim());
      //_Style = new CssStyleDeclaration(match, this, readOnly, Origin);

      Group selectorMatches = match.Groups["selector"];

      int len = selectorMatches.Captures.Count;
      ArrayList sels = new ArrayList();
      for(int i = 0; i<len; i++)
      {
                string str = DeReplaceStrings(selectorMatches.Captures[i].Value.Trim());
        if(str.Length > 0)
        {
          sels.Add(new CssXPathSelector(str));
        }
      }
      XPathSelectors = (CssXPathSelector[])sels.ToArray(typeof(CssXPathSelector));
    }

    #endregion

    #region Public methods
    /// <summary>
    /// Used to find matching style rules in the cascading order
    /// </summary>
    /// <param name="elt">The element to find styles for</param>
    /// <param name="pseudoElt">The pseudo-element to find styles for</param>
    /// <param name="ml">The medialist that the document is using</param>
    /// <param name="csd">A CssStyleDeclaration that holds the collected styles</param>
    protected internal override void GetStylesForElement(XmlElement elt, string pseudoElt, MediaList ml, CssCollectedStyleDeclaration csd)
    {
      XPathNavigator nav = elt.CreateNavigator();
      foreach(CssXPathSelector sel in XPathSelectors)
      {
        // TODO: deal with pseudoElt
        if(sel != null && sel.Matches(nav))
        {
          ((CssStyleDeclaration)Style).GetStylesForElement(csd, sel.Specificity);
          break;
        }
      }
    }
    #endregion

    #region Private fields
    private CssXPathSelector[] XPathSelectors;
    #endregion

    #region Implementation of ICssStyleRule
    /// <summary>
    /// The textual representation of the selector for the rule set. The implementation may have stripped out insignificant whitespace while parsing the selector.
    /// </summary>
    /// <exception cref="DomException">SYNTAX_ERR: Raised if the specified CSS string value has a syntax error and is unparsable.</exception>
    /// <exception cref="DomException">NO_MODIFICATION_ALLOWED_ERR: Raised if this rule is readonly</exception>
    public string SelectorText
    {
      get
      {
        string ret = String.Empty;
        foreach(CssXPathSelector sel in XPathSelectors)
        {
          ret += sel.CssSelector + ",";
        }
        return ret.Substring(0, ret.Length-1);
      }
      set
      {
        // TODO: invalidate
        throw new NotImplementedException("setting SelectorText");

      }
    }

    /// <summary>
    /// The entire text of the CssStyleRule
    /// </summary>
    public override string CssText
    {
      get
      {
        return SelectorText + "{" + ((CssStyleDeclaration)Style).CssText + "}";
      }
    }

    private CssStyleDeclaration _Style;
    /// <summary>
    /// The declaration-block of this rule set.
    /// </summary>
    public ICssStyleDeclaration Style
    {
      get
      {
        return _Style;
      }
    }



    #endregion

    #region Implementation of ICssRule
    /// <summary>
    /// The type of the rule. The expectation is that binding-specific casting methods can be used to cast down from an instance of the CSSRule interface to the specific derived interface implied by the type.
    /// </summary>
    public override CssRuleType Type
    {
      get
      {
        return CssRuleType.StyleRule;
      }
    }
    #endregion

  }
}