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      1 // Copyright (c) 2011 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 CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_BUNDLE_H_
      6 #define CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_BUNDLE_H_
      7 #pragma once
      8 
      9 #include <map>
     10 #include <string>
     11 #include <vector>
     12 
     13 #include "base/memory/linked_ptr.h"
     14 
     15 class DictionaryValue;
     16 
     17 // Contains localized extension messages for one locale. Any messages that the
     18 // locale does not provide are pulled from the default locale.
     19 class ExtensionMessageBundle {
     20  public:
     21   typedef std::map<std::string, std::string> SubstitutionMap;
     22   typedef std::vector<linked_ptr<DictionaryValue> > CatalogVector;
     23 
     24   // JSON keys of interest for messages file.
     25   static const char* kContentKey;
     26   static const char* kMessageKey;
     27   static const char* kPlaceholdersKey;
     28 
     29   // Begin/end markers for placeholders and messages
     30   static const char* kPlaceholderBegin;
     31   static const char* kPlaceholderEnd;
     32   static const char* kMessageBegin;
     33   static const char* kMessageEnd;
     34 
     35   // Reserved message names in the dictionary.
     36   // Update i18n documentation when adding new reserved value.
     37   static const char* kUILocaleKey;
     38   // See http://code.google.com/apis/gadgets/docs/i18n.html#BIDI for
     39   // description.
     40   // TODO(cira): point to chrome docs once they are out.
     41   static const char* kBidiDirectionKey;
     42   static const char* kBidiReversedDirectionKey;
     43   static const char* kBidiStartEdgeKey;
     44   static const char* kBidiEndEdgeKey;
     45   // Extension id gets added in the
     46   // browser/renderer_host/resource_message_filter.cc to enable message
     47   // replacement for non-localized extensions.
     48   static const char* kExtensionIdKey;
     49 
     50   // Values for some of the reserved messages.
     51   static const char* kBidiLeftEdgeValue;
     52   static const char* kBidiRightEdgeValue;
     53 
     54   // Creates ExtensionMessageBundle or returns NULL if there was an error.
     55   // Expects locale_catalogs to be sorted from more specific to less specific,
     56   // with default catalog at the end.
     57   static ExtensionMessageBundle* Create(const CatalogVector& locale_catalogs,
     58                                         std::string* error);
     59 
     60   // Get message from the catalog with given key.
     61   // Returned message has all of the internal placeholders resolved to their
     62   // value (content).
     63   // Returns empty string if it can't find a message.
     64   // We don't use simple GetMessage name, since there is a global
     65   // #define GetMessage GetMessageW override in Chrome code.
     66   std::string GetL10nMessage(const std::string& name) const;
     67 
     68   // Get message from the given catalog with given key.
     69   static std::string GetL10nMessage(const std::string& name,
     70                                     const SubstitutionMap& dictionary);
     71 
     72   // Number of messages in the catalog.
     73   // Used for unittesting only.
     74   size_t size() const { return dictionary_.size(); }
     75 
     76   // Replaces all __MSG_message__ with values from the catalog.
     77   // Returns false if there is a message in text that's not defined in the
     78   // dictionary.
     79   bool ReplaceMessages(std::string* text, std::string* error) const;
     80   // Static version that accepts dictionary.
     81   static bool ReplaceMessagesWithExternalDictionary(
     82       const SubstitutionMap& dictionary, std::string* text, std::string* error);
     83 
     84   // Replaces each occurance of variable placeholder with its value.
     85   // I.e. replaces __MSG_name__ with value from the catalog with the key "name".
     86   // Returns false if for a valid message/placeholder name there is no matching
     87   // replacement.
     88   // Public for easier unittesting.
     89   static bool ReplaceVariables(const SubstitutionMap& variables,
     90                                const std::string& var_begin,
     91                                const std::string& var_end,
     92                                std::string* message,
     93                                std::string* error);
     94 
     95   // Allow only ascii 0-9, a-z, A-Z, and _ in the variable name.
     96   // Returns false if the input is empty or if it has illegal characters.
     97   static bool IsValidName(const std::string& name);
     98 
     99   // Getter for dictionary_.
    100   const SubstitutionMap* dictionary() const { return &dictionary_; }
    101 
    102   ~ExtensionMessageBundle();
    103 
    104  private:
    105   // Testing friend.
    106   friend class ExtensionMessageBundleTest;
    107 
    108   // Use Create to create ExtensionMessageBundle instance.
    109   ExtensionMessageBundle();
    110 
    111   // Initializes the instance from the contents of vector of catalogs.
    112   // If the key is not present in more specific catalog we fall back to next one
    113   // (less specific).
    114   // Returns false on error.
    115   bool Init(const CatalogVector& locale_catalogs, std::string* error);
    116 
    117   // Appends locale specific reserved messages to the dictionary.
    118   // Returns false if there was a conflict with user defined messages.
    119   bool AppendReservedMessagesForLocale(const std::string& application_locale,
    120                                        std::string* error);
    121 
    122   // Helper methods that navigate JSON tree and return simplified message.
    123   // They replace all $PLACEHOLDERS$ with their value, and return just key/value
    124   // of the message.
    125   bool GetMessageValue(const std::string& key,
    126                        const DictionaryValue& catalog,
    127                        std::string* value,
    128                        std::string* error) const;
    129 
    130   // Get all placeholders for a given message from JSON subtree.
    131   bool GetPlaceholders(const DictionaryValue& name_tree,
    132                        const std::string& name_key,
    133                        SubstitutionMap* placeholders,
    134                        std::string* error) const;
    135 
    136   // For a given message, replaces all placeholders with their actual value.
    137   // Returns false if replacement failed (see ReplaceVariables).
    138   bool ReplacePlaceholders(const SubstitutionMap& placeholders,
    139                            std::string* message,
    140                            std::string* error) const;
    141 
    142   // Holds all messages for application locale.
    143   SubstitutionMap dictionary_;
    144 };
    145 
    146 ///////////////////////////////////////////////////////////////////////////////
    147 //
    148 // Renderer helper typedefs and functions.
    149 //
    150 ///////////////////////////////////////////////////////////////////////////////
    151 
    152 // A map of message name to message.
    153 typedef std::map<std::string, std::string> L10nMessagesMap;
    154 
    155 // A map of extension ID to l10n message map.
    156 typedef std::map<std::string, L10nMessagesMap > ExtensionToL10nMessagesMap;
    157 
    158 // Returns the extension_id to messages map.
    159 ExtensionToL10nMessagesMap* GetExtensionToL10nMessagesMap();
    160 
    161 // Returns message map that matches given extension_id, or NULL.
    162 L10nMessagesMap* GetL10nMessagesMap(const std::string& extension_id);
    163 
    164 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_BUNDLE_H_
    165