extensions/browser/file_highlighter.h

   1 // Copyright 2013 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 #ifndef EXTENSIONS_BROWSER_FILE_HIGHLIGHTER_H_
   6 #define EXTENSIONS_BROWSER_FILE_HIGHLIGHTER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11
  12 namespace base {
  13 class DictionaryValue;
  14 }
  15
  16 namespace extensions {
  17
  18 // The FileHighlighter class is used in order to isolate and highlight a portion
  19 // of a given file (in string form). The Highlighter will split the source into
  20 // three portions: the portion before the highlighted feature, the highlighted
  21 // feature, and the portion following the highlighted feature.
  22 // The file will be parsed for highlighting upon construction of the Highlighter
  23 // object.
  24 class FileHighlighter {
  25  public:
  26   virtual ~FileHighlighter();
  27
  28   // Get the portion of the manifest which should not be highlighted and is
  29   // before the feature.
  30   std::string GetBeforeFeature() const;
  31
  32   // Get the feature portion of the manifest, which should be highlighted.
  33   std::string GetFeature() const;
  34
  35   // Get the portion of the manifest which should not be highlighted and is
  36   // after the feature.
  37   std::string GetAfterFeature() const;
  38
  39   // Populate a DictionaryValue with the highlighted portions (in UTF16) of the
  40   // source file.
  41   void SetHighlightedRegions(base::DictionaryValue* dict) const;
  42
  43  protected:
  44   explicit FileHighlighter(const std::string& contents);
  45
  46   // The contents of the file we are parsing.
  47   std::string contents_;
  48
  49   // The start of the feature.
  50   size_t start_;
  51
  52   // The end of the feature.
  53   size_t end_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(FileHighlighter);
  56 };
  57
  58 // Use the ManifestHighlighter class to find the bounds of a feature in the
  59 // manifest.
  60 // A feature can be at any level in the hierarchy. The "start" of a feature is
  61 // the first character of the feature name, or the beginning quote of the name,
  62 // if present. The "end" of a feature is wherever the next item at the same
  63 // level starts.
  64 // For instance, the bounds for the 'permissions' feature at the top level could
  65 // be '"permissions": { "tabs", "history", "downloads" }', but the feature for
  66 // 'tabs' within 'permissions' would just be '"tabs"'.
  67 // We can't use the JSONParser to do this, because we want to display the actual
  68 // manifest, and once we parse it into Values, we lose any formatting the user
  69 // may have had.
  70 // If a feature cannot be found, the feature will have zero-length.
  71 class ManifestHighlighter : public FileHighlighter {
  72  public:
  73   ManifestHighlighter(const std::string& manifest,
  74                       const std::string& key,
  75                       const std::string& specific /* optional */);
  76   ~ManifestHighlighter() override;
  77
  78  private:
  79   // Called from the constructor; determine the start and end bounds of a
  80   // feature, using both the key and specific information.
  81   void Parse(const std::string& key, const std::string& specific);
  82
  83   // Find the bounds of any feature, either a full key or a specific item within
  84   // the key. |enforce_at_top_level| means that the feature we find must be at
  85   // the same level as |start_| (i.e., ignore nested elements).
  86   // Returns true on success.
  87   bool FindBounds(const std::string& feature, bool enforce_at_top_level);
  88
  89   // Finds the end of the feature.
  90   void FindBoundsEnd(const std::string& feature, size_t local_start);
  91
  92   DISALLOW_COPY_AND_ASSIGN(ManifestHighlighter);
  93 };
  94
  95 // Use the SourceHighlighter to highlight a particular line in a given source
  96 // file.
  97 class SourceHighlighter : public FileHighlighter {
  98  public:
  99   SourceHighlighter(const std::string& source, size_t line_number);
 100   ~SourceHighlighter() override;
 101
 102  private:
 103   // Called from the constructor; determine the bounds of the line in the source
 104   // file.
 105   void Parse(size_t line_number);
 106
 107   DISALLOW_COPY_AND_ASSIGN(SourceHighlighter);
 108 };
 109
 110 }  // namespace extensions
 111
 112 #endif  // EXTENSIONS_BROWSER_FILE_HIGHLIGHTER_H_