// Copyright 2016 The Chromium Embedded Framework Authors. Portions copyright
// 2013 The Chromium Authors. All rights reserved. Use of this source code is
// governed by a BSD-style license that can be found in the LICENSE file.

#ifndef CEF_TESTS_CEFCLIENT_BROWSER_OSR_IME_HANDLER_WIN_H_
#define CEF_TESTS_CEFCLIENT_BROWSER_OSR_IME_HANDLER_WIN_H_
#pragma once

#include <windows.h>

#include <vector>

#include "include/internal/cef_types_wrappers.h"

namespace client {

// Handles IME for the native parent window that hosts an off-screen browser.
// This object is only accessed on the CEF UI thread.
class OsrImeHandlerWin {
 public:
  explicit OsrImeHandlerWin(HWND hwnd);
  virtual ~OsrImeHandlerWin();

  // Retrieves whether or not there is an ongoing composition.
  bool is_composing() const { return is_composing_; }

  // Retrieves the input language from Windows and update it.
  void SetInputLanguage();

  // Creates the IME caret windows if required.
  void CreateImeWindow();

  // Destroys the IME caret windows.
  void DestroyImeWindow();

  // Cleans up the all resources attached to the given IMM32Manager object, and
  // reset its composition status.
  void CleanupComposition();

  // Resets the composition status and cancels the ongoing composition.
  void ResetComposition();

  // Retrieves a composition result of the ongoing composition if it exists.
  bool GetResult(LPARAM lparam, CefString& result);

  // Retrieves the current composition status of the ongoing composition.
  // Includes composition text, underline information and selection range in the
  // composition text. IMM32 does not support char selection.
  bool GetComposition(LPARAM lparam,
                      CefString& composition_text,
                      std::vector<CefCompositionUnderline>& underlines,
                      int& composition_start);

  // Enables the IME attached to the given window.
  virtual void EnableIME();

  // Disables the IME attached to the given window.
  virtual void DisableIME();

  // Cancels an ongoing composition of the IME.
  virtual void CancelIME();

  // Updates the IME caret position of the given window.
  void UpdateCaretPosition(uint32_t index);

  // Updates the composition range. |selected_range| is the range of characters
  // that have been selected. |character_bounds| is the bounds of each character
  // in view device coordinates.
  void ChangeCompositionRange(const CefRange& selection_range,
                              const std::vector<CefRect>& character_bounds);

  // Updates the position of the IME windows.
  void MoveImeWindow();

 private:
  // Retrieves the composition information.
  void GetCompositionInfo(HIMC imm_context,
                          LPARAM lparam,
                          CefString& composition_text,
                          std::vector<CefCompositionUnderline>& underlines,
                          int& composition_start);

  // Retrieves a string from the IMM.
  bool GetString(HIMC imm_context, WPARAM lparam, int type, CefString& result);

  // Represents whether or not there is an ongoing composition.
  bool is_composing_ = false;

  // The current composition character range and its bounds.
  std::vector<CefRect> composition_bounds_;

  // The current input Language ID retrieved from Windows -
  // used for processing language-specific operations in IME.
  LANGID input_language_id_;

  // Represents whether or not the current input context has created a system
  // caret to set the position of its IME candidate window.
  bool system_caret_ = false;

  // The rectangle of the input caret retrieved from a renderer process.
  CefRect ime_rect_;

  // The current cursor index in composition string.
  uint32_t cursor_index_;

  // The composition range in the string. This may be used to determine the
  // offset in composition bounds.
  CefRange composition_range_;

  // Hwnd associated with this instance.
  HWND hwnd_;
};

}  // namespace client

#endif  // CEF_TESTS_CEFCLIENT_BROWSER_OSR_IME_HANDLER_WIN_H_