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#ifndef MOZC_CONVERTER_CHARACTER_FORM_MANAGER_H_
#define MOZC_CONVERTER_CHARACTER_FORM_MANAGER_H_

#include <string>
#include <vector>
#include <utility>
#include "base/base.h"
#include "config/config.pb.h"

namespace mozc {

class CharacterFormManagerData;
template <class T> class Singleton;

class CharacterFormManager {
 public:
  // return the preference of character form.
  // This method cannot return the preference,
  // if str has two set of string groups having different preferences.
  // e.g., GetPreeditCharacterForm("グーグル012") returns NO_CONVERSION
  config::Config::CharacterForm GetPreeditCharacterForm(
      const string &input) const;

  config::Config::CharacterForm GetConversionCharacterForm(
      const string &input) const;

  // convert string according to the config rules
  void ConvertPreeditString(const string &input,
                            string *output) const;
  void ConvertConversionString(const string &input,
                               string *output) const;

  // Convert string according to the config rules.
  // if alternate output, which should be shown next to
  // the output, is defined, it is stored into alternative_output.
  // If alternative_output is not required, you can pass NULL.
  // e.g., output = "@" alternative_output = "＠"
  // return true if both output and alternative_output are defined.
  bool ConvertPreeditStringWithAlternative(
      const string &input, string *output,
      string *alternative_output) const;

  bool ConvertConversionStringWithAlternative(
      const string &input, string *output,
      string *alternative_output) const;

  // Call this method after user fixed the final result.
  // If a character has "LAST_FORM" preference in the config,
  // SetCharacterForm() stores the last character form into local file.
  // Next time user calls GetPreeditCharacterForm() or
  // GetConversionCharacterForm(), the preference is restored.
  void SetCharacterForm(const string &input,
                        config::Config::CharacterForm form);

  // Guess the character form of str and call
  // SetCharacterForm with this result.
  // Call this method after user fixed the final result.
  // It is more useful to call GuessAndSetCharacterForm(), as
  // you don't need to pass the form.
  // You can just pass the final final conversion string to this method.
  void GuessAndSetCharacterForm(const string &input);

  // clear history data
  // This method does not clear config data
  void ClearHistory();

  // clear internal rule
  void Clear();

  // Add a rule
  // Example:
  // AddPreeditRule("[]{}()", config::Config::LAST_FORM);
  // AddPreeditRule("+=", config::Config::HALF_WIDTH);
  // The all characters in str are treated as the same group.
  void AddPreeditRule(const string &input,
                             config::Config::CharacterForm form);

  void AddConversionRule(const string &input,
                                config::Config::CharacterForm form);

  // Load Default rule
  void SetDefaultRule();

  // reload explicitly
  void Reload();

  // utility function: pass character form
  static void ConvertWidth(const string &input, string *output,
                           config::Config::CharacterForm form);

  enum FormType {
    UNKNOWN_FORM,
    HALF_WIDTH,
    FULL_WIDTH
  };

  // Return form tyeps for given two pair of strings.
  // This function tries to find the difference between
  // |input1| and |input2| and find the place where the script
  // form (halfwidth/fullwidth) is different. This function returns
  // true if input1 or input2 needs to have full/half width anotation.
  //
  // Example:
  //  input1="ABCぐーぐる input2="ＡＢＣ"
  //  form1=Half form2=Full
  //
  // If input1 and input2 have mixed form types and the result
  // is ambigous, this function returns false.
  //
  // Ambiguous case:
  //  input1="ABC１２３" input2="ＡＢＣ123"
  //  return false.
  static bool GetFormTypesFromStringPair(const string &input1,
                                         FormType *form1,
                                         const string &input2,
                                         FormType *form2);

  // return singleton class
  static CharacterFormManager* GetCharacterFormManager();

 private:
  friend class Singleton<CharacterFormManager>;

  CharacterFormManager();
  virtual ~CharacterFormManager();
  scoped_ptr<CharacterFormManagerData> data_;
};
}  // namespace mozc
#endif  //  MOZC_SESSION_CHARACTER_FORM_MANAGER_H_