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//
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//
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// notice, this list of conditions and the following disclaimer.
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// in the documentation and/or other materials provided with the
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//
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "chewing/chewing_session_factory.h"

#include <pwd.h>

#include "base/singleton.h"
#include "base/util.h"
#include "chewing/session.h"
#include "converter/empty_user_data_manager.h"

#if defined(OS_CHROMEOS)
DEFINE_string(datapath, "/usr/share/chewing",
              "the default path of libchewing");
#else
DEFINE_string(datapath, "/usr/share/libchewing3/chewing",
              "the default path of libchewing");
#endif

namespace mozc {
string GetHashPath() {
  // The logic below is copied from Util::GetUserProfileDirectory().
  string dir;
  char buf[1024];
  struct passwd pw, *ppw;
  const uid_t uid = geteuid();
  CHECK_EQ(0, getpwuid_r(uid, &pw, buf, sizeof(buf), &ppw))
      << "Can't get passwd entry for uid " << uid << ".";
  CHECK_LT(0, strlen(pw.pw_dir))
      << "Home directory for uid " << uid << " is not set.";
#if defined(OS_CHROMEOS)
  dir = Util::JoinPath(pw.pw_dir, "user/.chewing");
#else
  dir = Util::JoinPath(pw.pw_dir, ".chewing");
#endif
  return dir;
}

namespace chewing {
// The default session factory implementation for chewing.  We do not
// use the implementation in session/session_factory.cc.  We do not
// even link to it because the default session factory refers to the
// Japanese language models / Japanese vocabulary which we don't want
// here.
ChewingSessionFactory::ChewingSessionFactory() {
  string hash_path = GetHashPath();
  if (!Util::DirectoryExists(hash_path)) {
    string hash_dir = Util::Dirname(hash_path);
    // In Chrome OS, hash_dir would be ~/user, which might not exist.
    if (Util::DirectoryExists(hash_dir) ||
        Util::CreateDirectory(hash_dir)) {
      Util::CreateDirectory(hash_path);
    }
  }
  ::chewing_Init(FLAGS_datapath.c_str(), hash_path.c_str());
}

ChewingSessionFactory::~ChewingSessionFactory() {
  ::chewing_Terminate();
}

mozc::session::SessionInterface *ChewingSessionFactory::NewSession() {
  return new mozc::chewing::Session();
}

UserDataManagerInterface *ChewingSessionFactory::GetUserDataManager() {
  return Singleton<EmptyUserDataManager>::get();
}

bool ChewingSessionFactory::IsAvailable() const {
  return true;
}
}  // namespace session
}  // namespace mozc