content/renderer/android/content_detector.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/renderer/android/content_detector.h"
   6
   7 #include "base/logging.h"
   8 #include "third_party/WebKit/public/platform/WebPoint.h"
   9 #include "third_party/WebKit/public/web/WebHitTestResult.h"
  10 #include "third_party/WebKit/public/web/WebSurroundingText.h"
  11
  12 using blink::WebRange;
  13 using blink::WebSurroundingText;
  14
  15 namespace content {
  16
  17 ContentDetector::Result::Result() : valid(false) {}
  18
  19 ContentDetector::Result::Result(const blink::WebRange& content_boundaries,
  20                                 const std::string& text,
  21                                 const GURL& intent_url)
  22   : valid(true),
  23     content_boundaries(content_boundaries),
  24     text(text),
  25     intent_url(intent_url) {
  26 }
  27
  28 ContentDetector::Result::~Result() {}
  29
  30 ContentDetector::Result ContentDetector::FindTappedContent(
  31     const blink::WebHitTestResult& hit_test) {
  32   if (hit_test.isNull())
  33     return Result();
  34
  35   std::string content_text;
  36   blink::WebRange range = FindContentRange(hit_test, &content_text);
  37   if (range.isNull())
  38     return Result();
  39
  40   GURL intent_url = GetIntentURL(content_text);
  41   return Result(range, content_text, intent_url);
  42 }
  43
  44 WebRange ContentDetector::FindContentRange(
  45     const blink::WebHitTestResult& hit_test,
  46     std::string* content_text) {
  47   // As the surrounding text extractor looks at maxLength/2 characters on
  48   // either side of the hit point, we need to double max content length here.
  49   WebSurroundingText surrounding_text;
  50   surrounding_text.initialize(hit_test.node(), hit_test.localPoint(),
  51                               GetMaximumContentLength() * 2);
  52   if (surrounding_text.isNull())
  53     return WebRange();
  54
  55   base::string16 content = surrounding_text.textContent();
  56   if (content.empty())
  57     return WebRange();
  58
  59   size_t selected_offset = surrounding_text.hitOffsetInTextContent();
  60   for (size_t start_offset = 0; start_offset < content.length();) {
  61     size_t relative_start, relative_end;
  62     if (!FindContent(content.begin() + start_offset,
  63         content.end(), &relative_start, &relative_end, content_text)) {
  64       break;
  65     } else {
  66       size_t content_start = start_offset + relative_start;
  67       size_t content_end = start_offset + relative_end;
  68       DCHECK(content_end <= content.length());
  69
  70       if (selected_offset >= content_start && selected_offset < content_end) {
  71         WebRange range = surrounding_text.rangeFromContentOffsets(
  72             content_start, content_end);
  73         DCHECK(!range.isNull());
  74         return range;
  75       } else {
  76         start_offset += relative_end;
  77       }
  78     }
  79   }
  80
  81   return WebRange();
  82 }
  83
  84 }  // namespace content