mcs/class/System.XML/Mono.Xml.XPath/LocationPathPattern.cs

   1 //
   2 // Mono.Xml.XPath.LocationPathPattern
   3 //
   4 // Author:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //
   7 // (C) 2003 Ben Maurer
   8 //
   9
  10 using System;
  11 using System.Collections;
  12 using System.IO;
  13 using System.Xml;
  14 using System.Xml.Schema;
  15 using System.Xml.XPath;
  16 using System.Xml.Xsl;
  17
  18 namespace Mono.Xml.XPath {
  19         internal class LocationPathPattern : Pattern {
  20
  21                 internal LocationPathPattern patternPrevious;
  22                 internal bool isAncestor;
  23                 internal NodeTest nodeTest;
  24                 ExprFilter filter;
  25
  26                 public LocationPathPattern (NodeTest nodeTest)
  27                 {
  28                         this.nodeTest = nodeTest;
  29                 }
  30
  31                 public LocationPathPattern (ExprFilter filter)
  32                 {
  33                         this.filter = filter;
  34
  35                         while (! (filter.expr is NodeTest))
  36                                 filter = (ExprFilter)filter.expr;
  37
  38                         this.nodeTest = (NodeTest)filter.expr;
  39                 }
  40
  41                 internal void SetPreviousPattern (Pattern prev, bool isAncestor)
  42                 {
  43                         LocationPathPattern toSet = LastPathPattern;
  44                         toSet.patternPrevious = (LocationPathPattern)prev;
  45                         toSet.isAncestor = isAncestor;
  46                 }
  47
  48                 public override double DefaultPriority {
  49                         get {
  50                                 if (patternPrevious == null && filter == null) {
  51                                         NodeNameTest t = nodeTest as NodeNameTest;
  52                                         if (t != null) {
  53                                                 if (t.Name.Name == "*")
  54                                                         return -.25;
  55                                                 return 0;
  56                                         }
  57
  58                                         return -.5;
  59                                 }
  60                                 return .5;
  61                         }
  62                 }
  63
  64                 public override bool Matches (XPathNavigator node, XsltContext ctx)
  65                 {
  66                         if (! nodeTest.Match (ctx, node))
  67                                 return false;
  68
  69                         if (nodeTest is NodeTypeTest) {
  70                                 // node () is different in xslt patterns
  71                                 if (((NodeTypeTest)nodeTest).type == XPathNodeType.All &&
  72                                         (node.NodeType == XPathNodeType.Root ||
  73                                         node.NodeType == XPathNodeType.Attribute)
  74                                 )
  75                                 return false;
  76                         }
  77
  78                         if (filter == null && patternPrevious == null)
  79                                 return true;
  80
  81                         if (patternPrevious != null) {
  82                                 if (!isAncestor) {
  83                                         XPathNavigator parent = node.Clone ();
  84                                         parent.MoveToParent ();
  85                                         if (!patternPrevious.Matches (parent, ctx))
  86                                                 return false;
  87                                 } else {
  88                                         XPathNavigator anc = node.Clone ();
  89                                         while (true) {
  90                                                 if (!anc.MoveToParent ())
  91                                                         return false;
  92
  93                                                 if (patternPrevious.Matches (anc, ctx))
  94                                                         break;
  95                                         }
  96                                 }
  97                         }
  98
  99
 100                         if (filter == null)
 101                                 return true;
 102
 103                         XPathNavigator p = node.Clone ();
 104                         p.MoveToParent ();
 105                         BaseIterator matches = filter.EvaluateNodeSet (new NullIterator (p, ctx));
 106
 107                         while (matches.MoveNext ()) {
 108                                 if (node.IsSamePosition (matches.Current))
 109                                         return true;
 110                         }
 111
 112                         return false;
 113                 }
 114
 115                 public override string ToString ()
 116                 {
 117                         string ret = "";
 118                         if (patternPrevious != null) ret = patternPrevious.ToString () + (isAncestor ? "//" : "/");
 119                         if (filter != null) ret += filter.ToString ();
 120                         else ret += nodeTest.ToString ();
 121
 122                         return ret;
 123                 }
 124
 125                 public LocationPathPattern LastPathPattern {
 126                         get {
 127                                 LocationPathPattern ret = this;
 128
 129                                 while (ret.patternPrevious != null)
 130                                         ret = ret.patternPrevious;
 131
 132                                 return ret;
 133                         }
 134                 }
 135         }
 136 }