1 /* 2 * Copyright (C) 2012 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "config.h" 32 #include "core/editing/SurroundingText.h" 33 34 #include "core/dom/Document.h" 35 #include "core/dom/Element.h" 36 #include "core/dom/Position.h" 37 #include "core/dom/Range.h" 38 #include "core/editing/TextIterator.h" 39 40 namespace WebCore { 41 42 SurroundingText::SurroundingText(const Range& range, unsigned maxLength) 43 : m_startOffsetInContent(0) 44 , m_endOffsetInContent(0) 45 { 46 initialize(range.startPosition(), range.endPosition(), maxLength); 47 } 48 49 SurroundingText::SurroundingText(const Position& position, unsigned maxLength) 50 : m_startOffsetInContent(0) 51 , m_endOffsetInContent(0) 52 { 53 initialize(position, position, maxLength); 54 } 55 56 void SurroundingText::initialize(const Position& startPosition, const Position& endPosition, unsigned maxLength) 57 { 58 ASSERT(startPosition.document() == endPosition.document()); 59 60 const unsigned halfMaxLength = maxLength / 2; 61 62 Document* document = startPosition.document(); 63 // The position will have no document if it is null (as in no position). 64 if (!document) 65 return; 66 67 // The forward range starts at the selection end and ends at the document's 68 // end. It will then be updated to only contain the text in the text in the 69 // right range around the selection. 70 RefPtrWillBeRawPtr<Range> forwardRange = Range::create(*document, endPosition, lastPositionInNode(document->documentElement()).parentAnchoredEquivalent()); 71 CharacterIterator forwardIterator(forwardRange.get(), TextIteratorStopsOnFormControls); 72 // FIXME: why do we stop going trough the text if we were not able to select something on the right? 73 if (!forwardIterator.atEnd()) 74 forwardIterator.advance(maxLength - halfMaxLength); 75 76 forwardRange = forwardIterator.range(); 77 if (!forwardRange || !Range::create(*document, endPosition, forwardRange->startPosition())->text().length()) { 78 ASSERT(forwardRange); 79 return; 80 } 81 82 // Same as with the forward range but with the backward range. The range 83 // starts at the document's start and ends at the selection start and will 84 // be updated. 85 RefPtrWillBeRawPtr<Range> backwardsRange = Range::create(*document, firstPositionInNode(document->documentElement()).parentAnchoredEquivalent(), startPosition); 86 BackwardsCharacterIterator backwardsIterator(backwardsRange.get(), TextIteratorStopsOnFormControls); 87 if (!backwardsIterator.atEnd()) 88 backwardsIterator.advance(halfMaxLength); 89 90 backwardsRange = backwardsIterator.range(); 91 if (!backwardsRange) { 92 ASSERT(backwardsRange); 93 return; 94 } 95 96 m_startOffsetInContent = Range::create(*document, backwardsRange->endPosition(), startPosition)->text().length(); 97 m_endOffsetInContent = Range::create(*document, backwardsRange->endPosition(), endPosition)->text().length(); 98 m_contentRange = Range::create(*document, backwardsRange->endPosition(), forwardRange->startPosition()); 99 ASSERT(m_contentRange); 100 } 101 102 PassRefPtrWillBeRawPtr<Range> SurroundingText::rangeFromContentOffsets(unsigned startOffsetInContent, unsigned endOffsetInContent) 103 { 104 if (startOffsetInContent >= endOffsetInContent || endOffsetInContent > content().length()) 105 return nullptr; 106 107 CharacterIterator iterator(m_contentRange.get()); 108 109 ASSERT(!iterator.atEnd()); 110 iterator.advance(startOffsetInContent); 111 112 ASSERT(iterator.range()); 113 Position start = iterator.range()->startPosition(); 114 115 ASSERT(!iterator.atEnd()); 116 iterator.advance(endOffsetInContent - startOffsetInContent); 117 118 ASSERT(iterator.range()); 119 Position end = iterator.range()->startPosition(); 120 121 ASSERT(start.document()); 122 return Range::create(*start.document(), start, end); 123 } 124 125 String SurroundingText::content() const 126 { 127 if (m_contentRange) 128 return m_contentRange->text(); 129 return String(); 130 } 131 132 unsigned SurroundingText::startOffsetInContent() const 133 { 134 return m_startOffsetInContent; 135 } 136 137 unsigned SurroundingText::endOffsetInContent() const 138 { 139 return m_endOffsetInContent; 140 } 141 142 } // namespace WebCore 143