platform/platform-impl/src/com/intellij/openapi/editor/impl/RangeIterator.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.openapi.editor.impl;
  17
  18 import com.intellij.openapi.diagnostic.Logger;
  19 import com.intellij.openapi.editor.FoldingModel;
  20 import com.intellij.openapi.editor.highlighter.HighlighterIterator;
  21 import com.intellij.openapi.editor.markup.TextAttributes;
  22 import com.intellij.openapi.util.Condition;
  23 import com.intellij.openapi.util.TextRange;
  24 import gnu.trove.Equality;
  25
  26 class RangeIterator {
  27   private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.editor.impl.RangeIterator");
  28   private static final int NO_NEXT = -1;
  29   private int myRangeEnd;
  30
  31   public interface Gaps {
  32     boolean isGapAt(int offset);
  33   }
  34
  35   private final HighlighterIterator mySource;
  36   private final Equality<TextAttributes> myEquality;
  37   private final Gaps myGaps;
  38   private final Condition<TextAttributes> myFilter;
  39   private boolean mySourceOutOfRange = false;
  40
  41   private int myStart;
  42   private int myEnd;
  43   private TextAttributes myTextAttributes;
  44   private int myNextExpanded;
  45
  46   public RangeIterator(Gaps foldingModel, Equality<TextAttributes> equality,
  47                        HighlighterIterator source, Condition<TextAttributes> filter) {
  48     mySource = source;
  49     myGaps = foldingModel;
  50     myEquality = equality;
  51     myFilter = filter;
  52   }
  53
  54   public void init(TextRange range) {
  55     int rangeStart = range.getStartOffset();
  56     myRangeEnd = range.getEndOffset();
  57     while(!mySource.atEnd()) {
  58       boolean sourceBeforeRange = rangeStart > mySource.getEnd();
  59       if (!sourceBeforeRange) break;
  60       mySource.advance();
  61     }
  62     while (!mySource.atEnd() && !checkOutOfRange()) {
  63       if (myFilter.value(mySource.getTextAttributes())) break;
  64       mySource.advance();
  65     }
  66
  67     if (mySource.atEnd() || mySourceOutOfRange) myNextExpanded = NO_NEXT;
  68     else {
  69       myNextExpanded = findExpanded(mySource.getStart());
  70       if (myNextExpanded == NO_NEXT) myStart = NO_NEXT;
  71     }
  72   }
  73
  74   private boolean checkOutOfRange() {
  75     if (mySourceOutOfRange) return true;
  76     mySourceOutOfRange = mySource.getStart() > myRangeEnd;
  77     return mySourceOutOfRange;
  78   }
  79
  80   private void doAdvanceFrom(int start) {
  81     myStart = start;
  82     myEnd = myStart;
  83     doAdvance();
  84     if (mySource.atEnd()) myNextExpanded = NO_NEXT;
  85     else myNextExpanded = findExpanded(Math.max(myEnd, mySource.getStart()));
  86   }
  87
  88   private void doAdvance() {
  89     myStart = findExpanded(myStart);
  90     myEnd = findFolding(myStart, mySource.getEnd(), true);
  91     myTextAttributes = mySource.getTextAttributes();
  92     while (myEnd == mySource.getEnd()) {
  93       if (!advanceSource()) return;
  94       if (mySource.getStart() != myEnd) return;
  95       if (!myEquality.equals(myTextAttributes, mySource.getTextAttributes())) return;
  96       myEnd = findFolding(myEnd, mySource.getEnd(), true);
  97     }
  98   }
  99
 100   private boolean advanceSource() {
 101     if (mySource.atEnd()) return false;
 102     do {
 103       mySource.advance();
 104     } while (!(mySource.atEnd() || checkOutOfRange() || myFilter.value(mySource.getTextAttributes())));
 105     return !mySource.atEnd();
 106   }
 107
 108   private int findExpanded(int start) {
 109     start = findFolding(start, mySource.getEnd(), false);
 110     while (start == mySource.getEnd()) {
 111       if (!advanceSource()) return NO_NEXT;
 112       start = findFolding(mySource.getStart(), mySource.getEnd(), false);
 113     }
 114     return start;
 115   }
 116
 117   private int findFolding(int start, int end, boolean collapsed) {
 118     int position = start;
 119     while (position < end) {
 120       if (myGaps.isGapAt(position) == collapsed) break;
 121       else position++;
 122     }
 123     return position;
 124   }
 125
 126   public int getStart() {
 127     return myStart;
 128   }
 129
 130   public int getEnd() {
 131     return myEnd;
 132   }
 133
 134   public TextAttributes getTextAttributes() {
 135     LOG.assertTrue(myFilter.value(myTextAttributes));
 136     return myTextAttributes;
 137   }
 138
 139   public void advance() {
 140     doAdvanceFrom(myNextExpanded);
 141   }
 142
 143   public boolean atEnd() {
 144     return myStart == NO_NEXT || mySourceOutOfRange ||
 145            (mySource.atEnd() && (myNextExpanded == NO_NEXT ||
 146                                  myNextExpanded == mySource.getEnd()));
 147   }
 148
 149   public static class FoldingGaps implements Gaps {
 150     private final FoldingModel myFoldingModel;
 151
 152     public FoldingGaps(FoldingModel foldingModel) {
 153       myFoldingModel = foldingModel;
 154     }
 155
 156     public boolean isGapAt(int offset) {
 157       return myFoldingModel.isOffsetCollapsed(offset);
 158     }
 159   }
 160 }