/*

  Simple DirectMedia Layer

  Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied

  warranty.  In no event will the authors be held liable for any damages

  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,

  including commercial applications, and to alter it and redistribute it

  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not

     claim that you wrote the original software. If you use this software

     in a product, an acknowledgment in the product documentation would be

     appreciated but is not required.

  2. Altered source versions must be plainly marked as such, and must not be

     misrepresented as being the original software.

  3. This notice may not be removed or altered from any source distribution.

*/

#include "SDL_config.h"

#if SDL_VIDEO_DRIVER_WINDOWS

#include "SDL_windowsvideo.h"

#include "../../events/SDL_keyboard_c.h"

#include "../../events/scancodes_windows.h"

#include <imm.h>

#include <oleauto.h>

#ifndef SDL_DISABLE_WINDOWS_IME

static void IME_Init(SDL_VideoData *videodata, HWND hwnd);

static void IME_Enable(SDL_VideoData *videodata, HWND hwnd);

static void IME_Disable(SDL_VideoData *videodata, HWND hwnd);

static void IME_Quit(SDL_VideoData *videodata);

#endif /* !SDL_DISABLE_WINDOWS_IME */

#ifndef MAPVK_VK_TO_VSC

#define MAPVK_VK_TO_VSC     0

#endif

#ifndef MAPVK_VSC_TO_VK

#define MAPVK_VSC_TO_VK     1

#endif

#ifndef MAPVK_VK_TO_CHAR

#define MAPVK_VK_TO_CHAR    2

#endif

/* Alphabetic scancodes for PC keyboards */

BYTE alpha_scancodes[26] = {

    30, 48, 46, 32, 18, 33, 34, 35, 23, 36, 37, 38, 50, 49, 24,

    25, 16, 19, 31, 20, 22, 47, 17, 45, 21, 44

};

BYTE keypad_scancodes[10] = {

    82, 79, 80, 81, 75, 76, 77, 71, 72, 73

};

void

WIN_InitKeyboard(_THIS)

{

    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;

    int i;

    /* Make sure the alpha scancodes are correct.  T isn't usually remapped */

    if (MapVirtualKey('T', MAPVK_VK_TO_VSC) != alpha_scancodes['T' - 'A']) {

#if 0

        printf

            ("Fixing alpha scancode map, assuming US QWERTY layout!\nPlease send the following 26 lines of output to the SDL mailing list <sdl@libsdl.org>, including a description of your keyboard hardware.\n");

#endif

        for (i = 0; i < SDL_arraysize(alpha_scancodes); ++i) {

            alpha_scancodes[i] = MapVirtualKey('A' + i, MAPVK_VK_TO_VSC);

#if 0

            printf("%d = %d\n", i, alpha_scancodes[i]);

#endif

        }

    }

    if (MapVirtualKey(VK_NUMPAD0, MAPVK_VK_TO_VSC) != keypad_scancodes[0]) {

#if 0

        printf

            ("Fixing keypad scancode map!\nPlease send the following 10 lines of output to the SDL mailing list <sdl@libsdl.org>, including a description of your keyboard hardware.\n");

#endif

        for (i = 0; i < SDL_arraysize(keypad_scancodes); ++i) {

            keypad_scancodes[i] =

                MapVirtualKey(VK_NUMPAD0 + i, MAPVK_VK_TO_VSC);

#if 0

            printf("%d = %d\n", i, keypad_scancodes[i]);

#endif

        }

    }

	// windows scancode to SDL scancode table

    data->key_layout = windows_scancode_table;

    data->ime_com_initialized = SDL_FALSE;

    data->ime_threadmgr = 0;

    data->ime_initialized = SDL_FALSE;

    data->ime_enabled = SDL_FALSE;

    data->ime_available = SDL_FALSE;

    data->ime_hwnd_main = 0;

    data->ime_hwnd_current = 0;

    data->ime_himc = 0;

    data->ime_composition[0] = 0;

    data->ime_readingstring[0] = 0;

    data->ime_cursor = 0;

    data->ime_candlist = SDL_FALSE;

    SDL_memset(data->ime_candidates, 0, sizeof(data->ime_candidates));

    data->ime_candcount = 0;

    data->ime_candref = 0;

    data->ime_candsel = 0;

    data->ime_candpgsize = 0;

    data->ime_candlistindexbase = 0;

    data->ime_candvertical = SDL_TRUE;

    data->ime_dirty = SDL_FALSE;

    SDL_memset(&data->ime_rect, 0, sizeof(data->ime_rect));

    SDL_memset(&data->ime_candlistrect, 0, sizeof(data->ime_candlistrect));

    data->ime_winwidth = 0;

    data->ime_winheight = 0;

    data->ime_hkl = 0;

    data->ime_himm32 = 0;

    data->GetReadingString = 0;

    data->ShowReadingWindow = 0;

    data->ImmLockIMC = 0;

    data->ImmUnlockIMC = 0;

    data->ImmLockIMCC = 0;

    data->ImmUnlockIMCC = 0;

    data->ime_uiless = SDL_FALSE;

    data->ime_threadmgrex = 0;

    data->ime_uielemsinkcookie = TF_INVALID_COOKIE;

    data->ime_alpnsinkcookie = TF_INVALID_COOKIE;

    data->ime_openmodesinkcookie = TF_INVALID_COOKIE;

    data->ime_convmodesinkcookie = TF_INVALID_COOKIE;

    data->ime_uielemsink = 0;

    data->ime_ippasink = 0;

    WIN_UpdateKeymap();

    SDL_SetScancodeName(SDL_SCANCODE_APPLICATION, "Menu");

    SDL_SetScancodeName(SDL_SCANCODE_LGUI, "Left Windows");

    SDL_SetScancodeName(SDL_SCANCODE_RGUI, "Right Windows");

}

void

WIN_UpdateKeymap()

{

    int i;

    SDL_Scancode scancode;

    SDL_Keycode keymap[SDL_NUM_SCANCODES];

	for (i = 0; i < SDL_arraysize(keymap); ++i)

	{

		keymap[i] = SDL_SCANCODE_TO_KEYCODE( i );

	}

    for (i = 0; i < SDL_arraysize(windows_scancode_table); i++) {

		int vk;

        /* Make sure this scancode is a valid character scancode */

        scancode = windows_scancode_table[i];

        if (scancode == SDL_SCANCODE_UNKNOWN ) {

            continue;

        }

		/* Don't allow the number keys right above the qwerty row to translate or the top left key (grave/backquote) */

		/* not mapping numbers fixes the AZERTY layout (french) causing non-shifted number to appear by default */

		if ( scancode == SDL_SCANCODE_GRAVE ) {

			keymap[scancode]  = SDLK_BACKQUOTE;

			continue;

		}

		if ( scancode >= SDL_SCANCODE_1 && scancode <= SDL_SCANCODE_0 ) {

			 keymap[scancode] = SDLK_1 + ( scancode - SDL_SCANCODE_1 );

			continue;

		}

		vk =  MapVirtualKey(i, MAPVK_VSC_TO_VK);

		if ( vk ) {

			int ch;

			ch = (MapVirtualKey( vk, MAPVK_VK_TO_CHAR ) & 0x7FFF);

			 if ( ch )

			 {

				 if ( ch >= 'A' && ch <= 'Z' )

					keymap[scancode] =  SDLK_a + ( ch - 'A' );

				 else

					 keymap[scancode] = ch;

			 }

		}

    }

    SDL_SetKeymap(0, keymap, SDL_NUM_SCANCODES);

}

void

WIN_QuitKeyboard(_THIS)

{

#ifndef SDL_DISABLE_WINDOWS_IME

    IME_Quit((SDL_VideoData *)_this->driverdata);

#endif

}

void

WIN_StartTextInput(_THIS)

{

#ifndef SDL_DISABLE_WINDOWS_IME

    SDL_Window *window = SDL_GetKeyboardFocus();

    if (window) {

        HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

        SDL_VideoData *videodata = (SDL_VideoData *)_this->driverdata;

        SDL_GetWindowSize(window, &videodata->ime_winwidth, &videodata->ime_winheight);

        IME_Init(videodata, hwnd);

        IME_Enable(videodata, hwnd);

    }

#endif /* !SDL_DISABLE_WINDOWS_IME */

}

void

WIN_StopTextInput(_THIS)

{

#ifndef SDL_DISABLE_WINDOWS_IME

    SDL_Window *window = SDL_GetKeyboardFocus();

    if (window) {

        HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

        SDL_VideoData *videodata = (SDL_VideoData *)_this->driverdata;

        IME_Init(videodata, hwnd);

        IME_Disable(videodata, hwnd);

    }

#endif /* !SDL_DISABLE_WINDOWS_IME */

}

void

WIN_SetTextInputRect(_THIS, SDL_Rect *rect)

{

    SDL_VideoData *videodata = (SDL_VideoData *)_this->driverdata;

    if (!rect) {

        SDL_InvalidParamError("rect");

        return;

    }

    videodata->ime_rect = *rect;

}

#ifdef SDL_DISABLE_WINDOWS_IME

SDL_bool

IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoData *videodata)

{

    return SDL_FALSE;

}

void IME_Present(SDL_VideoData *videodata)

{

}

#else

#ifdef __GNUC__

#undef DEFINE_GUID

#define DEFINE_GUID(n,l,w1,w2,b1,b2,b3,b4,b5,b6,b7,b8) static const GUID n = {l,w1,w2,{b1,b2,b3,b4,b5,b6,b7,b8}}

DEFINE_GUID(IID_ITfInputProcessorProfileActivationSink,        0x71C6E74E,0x0F28,0x11D8,0xA8,0x2A,0x00,0x06,0x5B,0x84,0x43,0x5C);

DEFINE_GUID(IID_ITfUIElementSink,                              0xEA1EA136,0x19DF,0x11D7,0xA6,0xD2,0x00,0x06,0x5B,0x84,0x43,0x5C);

DEFINE_GUID(GUID_TFCAT_TIP_KEYBOARD,                           0x34745C63,0xB2F0,0x4784,0x8B,0x67,0x5E,0x12,0xC8,0x70,0x1A,0x31);

DEFINE_GUID(IID_ITfSource,                                     0x4EA48A35,0x60AE,0x446F,0x8F,0xD6,0xE6,0xA8,0xD8,0x24,0x59,0xF7);

DEFINE_GUID(IID_ITfUIElementMgr,                               0xEA1EA135,0x19DF,0x11D7,0xA6,0xD2,0x00,0x06,0x5B,0x84,0x43,0x5C);

DEFINE_GUID(IID_ITfCandidateListUIElement,                     0xEA1EA138,0x19DF,0x11D7,0xA6,0xD2,0x00,0x06,0x5B,0x84,0x43,0x5C);

DEFINE_GUID(IID_ITfReadingInformationUIElement,                0xEA1EA139,0x19DF,0x11D7,0xA6,0xD2,0x00,0x06,0x5B,0x84,0x43,0x5C);

DEFINE_GUID(IID_ITfThreadMgr,                                  0xAA80E801,0x2021,0x11D2,0x93,0xE0,0x00,0x60,0xB0,0x67,0xB8,0x6E);

DEFINE_GUID(CLSID_TF_ThreadMgr,                                0x529A9E6B,0x6587,0x4F23,0xAB,0x9E,0x9C,0x7D,0x68,0x3E,0x3C,0x50);

DEFINE_GUID(IID_ITfThreadMgrEx,                                0x3E90ADE3,0x7594,0x4CB0,0xBB,0x58,0x69,0x62,0x8F,0x5F,0x45,0x8C);

#endif

#define LANG_CHT MAKELANGID(LANG_CHINESE, SUBLANG_CHINESE_TRADITIONAL)

#define LANG_CHS MAKELANGID(LANG_CHINESE, SUBLANG_CHINESE_SIMPLIFIED)

#define MAKEIMEVERSION(major,minor) ((DWORD) (((BYTE)(major) << 24) | ((BYTE)(minor) << 16) ))

#define IMEID_VER(id) ((id) & 0xffff0000)

#define IMEID_LANG(id) ((id) & 0x0000ffff)

#define CHT_HKL_DAYI            ((HKL)0xE0060404)

#define CHT_HKL_NEW_PHONETIC    ((HKL)0xE0080404)

#define CHT_HKL_NEW_CHANG_JIE   ((HKL)0xE0090404)

#define CHT_HKL_NEW_QUICK       ((HKL)0xE00A0404)

#define CHT_HKL_HK_CANTONESE    ((HKL)0xE00B0404)

#define CHT_IMEFILENAME1        "TINTLGNT.IME"

#define CHT_IMEFILENAME2        "CINTLGNT.IME"

#define CHT_IMEFILENAME3        "MSTCIPHA.IME"

#define IMEID_CHT_VER42         (LANG_CHT | MAKEIMEVERSION(4, 2))

#define IMEID_CHT_VER43         (LANG_CHT | MAKEIMEVERSION(4, 3))

#define IMEID_CHT_VER44         (LANG_CHT | MAKEIMEVERSION(4, 4))

#define IMEID_CHT_VER50         (LANG_CHT | MAKEIMEVERSION(5, 0))

#define IMEID_CHT_VER51         (LANG_CHT | MAKEIMEVERSION(5, 1))

#define IMEID_CHT_VER52         (LANG_CHT | MAKEIMEVERSION(5, 2))

#define IMEID_CHT_VER60         (LANG_CHT | MAKEIMEVERSION(6, 0))

#define IMEID_CHT_VER_VISTA     (LANG_CHT | MAKEIMEVERSION(7, 0))

#define CHS_HKL                 ((HKL)0xE00E0804)

#define CHS_IMEFILENAME1        "PINTLGNT.IME"

#define CHS_IMEFILENAME2        "MSSCIPYA.IME"

#define IMEID_CHS_VER41         (LANG_CHS | MAKEIMEVERSION(4, 1))

#define IMEID_CHS_VER42         (LANG_CHS | MAKEIMEVERSION(4, 2))

#define IMEID_CHS_VER53         (LANG_CHS | MAKEIMEVERSION(5, 3))

#define LANG() LOWORD((videodata->ime_hkl))

#define PRIMLANG() ((WORD)PRIMARYLANGID(LANG()))

#define SUBLANG() SUBLANGID(LANG())

static void IME_UpdateInputLocale(SDL_VideoData *videodata);

static void IME_ClearComposition(SDL_VideoData *videodata);

static void IME_SetWindow(SDL_VideoData* videodata, HWND hwnd);

static void IME_SetupAPI(SDL_VideoData *videodata);

static DWORD IME_GetId(SDL_VideoData *videodata, UINT uIndex);

static void IME_SendEditingEvent(SDL_VideoData *videodata);

static void IME_DestroyTextures(SDL_VideoData *videodata);

#define SDL_IsEqualIID(riid1, riid2) SDL_IsEqualGUID(riid1, riid2)

#define SDL_IsEqualGUID(rguid1, rguid2) (!SDL_memcmp(rguid1, rguid2, sizeof(GUID)))

static SDL_bool UILess_SetupSinks(SDL_VideoData *videodata);

static void UILess_ReleaseSinks(SDL_VideoData *videodata);

static void UILess_EnableUIUpdates(SDL_VideoData *videodata);

static void UILess_DisableUIUpdates(SDL_VideoData *videodata);

static void

IME_Init(SDL_VideoData *videodata, HWND hwnd)

{

    if (videodata->ime_initialized)

        return;

    videodata->ime_hwnd_main = hwnd;

    if (SUCCEEDED(WIN_CoInitialize())) {

        videodata->ime_com_initialized = SDL_TRUE;

        CoCreateInstance(&CLSID_TF_ThreadMgr, NULL, CLSCTX_INPROC_SERVER, &IID_ITfThreadMgr, (LPVOID *)&videodata->ime_threadmgr);

    }

    videodata->ime_initialized = SDL_TRUE;

    videodata->ime_himm32 = SDL_LoadObject("imm32.dll");

    if (!videodata->ime_himm32) {

        videodata->ime_available = SDL_FALSE;

        return;

    }

    videodata->ImmLockIMC = (LPINPUTCONTEXT2 (WINAPI *)(HIMC))SDL_LoadFunction(videodata->ime_himm32, "ImmLockIMC");

    videodata->ImmUnlockIMC = (BOOL (WINAPI *)(HIMC))SDL_LoadFunction(videodata->ime_himm32, "ImmUnlockIMC");

    videodata->ImmLockIMCC = (LPVOID (WINAPI *)(HIMCC))SDL_LoadFunction(videodata->ime_himm32, "ImmLockIMCC");

    videodata->ImmUnlockIMCC = (BOOL (WINAPI *)(HIMCC))SDL_LoadFunction(videodata->ime_himm32, "ImmUnlockIMCC");

    IME_SetWindow(videodata, hwnd);

    videodata->ime_himc = ImmGetContext(hwnd);

    ImmReleaseContext(hwnd, videodata->ime_himc);

    if (!videodata->ime_himc) {

        videodata->ime_available = SDL_FALSE;

        IME_Disable(videodata, hwnd);

        return;

    }

    videodata->ime_available = SDL_TRUE;

    IME_UpdateInputLocale(videodata);

    IME_SetupAPI(videodata);

    videodata->ime_uiless = UILess_SetupSinks(videodata);

    IME_UpdateInputLocale(videodata);

    IME_Disable(videodata, hwnd);

}

static void

IME_Enable(SDL_VideoData *videodata, HWND hwnd)

{

    if (!videodata->ime_initialized || !videodata->ime_hwnd_current)

        return;

    if (!videodata->ime_available) {

        IME_Disable(videodata, hwnd);

        return;

    }

    if (videodata->ime_hwnd_current == videodata->ime_hwnd_main)

        ImmAssociateContext(videodata->ime_hwnd_current, videodata->ime_himc);

    videodata->ime_enabled = SDL_TRUE;

    IME_UpdateInputLocale(videodata);

    UILess_EnableUIUpdates(videodata);

}

static void

IME_Disable(SDL_VideoData *videodata, HWND hwnd)

{

    if (!videodata->ime_initialized || !videodata->ime_hwnd_current)

        return;

    IME_ClearComposition(videodata);

    if (videodata->ime_hwnd_current == videodata->ime_hwnd_main)

        ImmAssociateContext(videodata->ime_hwnd_current, (HIMC)0);

    videodata->ime_enabled = SDL_FALSE;

    UILess_DisableUIUpdates(videodata);

}

static void

IME_Quit(SDL_VideoData *videodata)

{

    if (!videodata->ime_initialized)

        return;

    UILess_ReleaseSinks(videodata);

    if (videodata->ime_hwnd_main)

        ImmAssociateContext(videodata->ime_hwnd_main, videodata->ime_himc);

    videodata->ime_hwnd_main = 0;

    videodata->ime_himc = 0;

    if (videodata->ime_himm32) {

        SDL_UnloadObject(videodata->ime_himm32);

        videodata->ime_himm32 = 0;

    }

    if (videodata->ime_threadmgr) {

        videodata->ime_threadmgr->lpVtbl->Release(videodata->ime_threadmgr);

        videodata->ime_threadmgr = 0;

    }

    if (videodata->ime_com_initialized) {

        WIN_CoUninitialize();

        videodata->ime_com_initialized = SDL_FALSE;

    }

    IME_DestroyTextures(videodata);

    videodata->ime_initialized = SDL_FALSE;

}

static void

IME_GetReadingString(SDL_VideoData *videodata, HWND hwnd)

{

    DWORD id = 0;

    HIMC himc = 0;

    WCHAR buffer[16];

    WCHAR *s = buffer;

    DWORD len = 0;

    INT err = 0;

    BOOL vertical = FALSE;

    UINT maxuilen = 0;

    static OSVERSIONINFOA osversion = {0};

    if (videodata->ime_uiless)

        return;

    videodata->ime_readingstring[0] = 0;

    if (!osversion.dwOSVersionInfoSize) {

        osversion.dwOSVersionInfoSize = sizeof(osversion);

        GetVersionExA(&osversion);

    }

    id = IME_GetId(videodata, 0);

    if (!id)

        return;

    himc = ImmGetContext(hwnd);

    if (!himc)

        return;

    if (videodata->GetReadingString) {

        len = videodata->GetReadingString(himc, 0, 0, &err, &vertical, &maxuilen);

        if (len) {

            if (len > SDL_arraysize(buffer))

                len = SDL_arraysize(buffer);

            len = videodata->GetReadingString(himc, len, s, &err, &vertical, &maxuilen);

        }

        SDL_wcslcpy(videodata->ime_readingstring, s, len);

    }

    else {

        LPINPUTCONTEXT2 lpimc = videodata->ImmLockIMC(himc);

        LPBYTE p = 0;

        s = 0;

        switch (id)

        {

        case IMEID_CHT_VER42:

        case IMEID_CHT_VER43:

        case IMEID_CHT_VER44:

            p = *(LPBYTE *)((LPBYTE)videodata->ImmLockIMCC(lpimc->hPrivate) + 24);

            if (!p)

                break;

            len = *(DWORD *)(p + 7*4 + 32*4);

            s = (WCHAR *)(p + 56);

            break;

        case IMEID_CHT_VER51:

        case IMEID_CHT_VER52:

        case IMEID_CHS_VER53:

            p = *(LPBYTE *)((LPBYTE)videodata->ImmLockIMCC(lpimc->hPrivate) + 4);

            if (!p)

                break;

            p = *(LPBYTE *)((LPBYTE)p + 1*4 + 5*4);

            if (!p)

                break;

            len = *(DWORD *)(p + 1*4 + (16*2+2*4) + 5*4 + 16*2);

            s = (WCHAR *)(p + 1*4 + (16*2+2*4) + 5*4);

            break;

        case IMEID_CHS_VER41:

            {

                int offset = (IME_GetId(videodata, 1) >= 0x00000002) ? 8 : 7;

                p = *(LPBYTE *)((LPBYTE)videodata->ImmLockIMCC(lpimc->hPrivate) + offset * 4);

                if (!p)

                    break;

                len = *(DWORD *)(p + 7*4 + 16*2*4);

                s = (WCHAR *)(p + 6*4 + 16*2*1);

            }

            break;

        case IMEID_CHS_VER42:

            if (osversion.dwPlatformId != VER_PLATFORM_WIN32_NT)

                break;

            p = *(LPBYTE *)((LPBYTE)videodata->ImmLockIMCC(lpimc->hPrivate) + 1*4 + 1*4 + 6*4);

            if (!p)

                break;

            len = *(DWORD *)(p + 1*4 + (16*2+2*4) + 5*4 + 16*2);

            s = (WCHAR *)(p + 1*4 + (16*2+2*4) + 5*4);

            break;

        }

        if (s)

            SDL_wcslcpy(videodata->ime_readingstring, s, len + 1);

        videodata->ImmUnlockIMCC(lpimc->hPrivate);

        videodata->ImmUnlockIMC(himc);

    }

    ImmReleaseContext(hwnd, himc);

    IME_SendEditingEvent(videodata);

}

static void

IME_InputLangChanged(SDL_VideoData *videodata)

{

    UINT lang = PRIMLANG();

    IME_UpdateInputLocale(videodata);

    if (!videodata->ime_uiless)

        videodata->ime_candlistindexbase = (videodata->ime_hkl == CHT_HKL_DAYI) ? 0 : 1;

    IME_SetupAPI(videodata);

    if (lang != PRIMLANG()) {

        IME_ClearComposition(videodata);

    }

}

static DWORD

IME_GetId(SDL_VideoData *videodata, UINT uIndex)

{

    static HKL hklprev = 0;

    static DWORD dwRet[2] = {0};

    DWORD dwVerSize = 0;

    DWORD dwVerHandle = 0;

    LPVOID lpVerBuffer = 0;

    LPVOID lpVerData = 0;

    UINT cbVerData = 0;

    char szTemp[256];

    HKL hkl = 0;

    DWORD dwLang = 0;

    if (uIndex >= sizeof(dwRet) / sizeof(dwRet[0]))

        return 0;

    hkl = videodata->ime_hkl;

    if (hklprev == hkl)

        return dwRet[uIndex];

    hklprev = hkl;

    dwLang = ((DWORD_PTR)hkl & 0xffff);

    if (videodata->ime_uiless && LANG() == LANG_CHT) {

        dwRet[0] = IMEID_CHT_VER_VISTA;

        dwRet[1] = 0;

        return dwRet[0];

    }

    if (hkl != CHT_HKL_NEW_PHONETIC

        && hkl != CHT_HKL_NEW_CHANG_JIE

        && hkl != CHT_HKL_NEW_QUICK

        && hkl != CHT_HKL_HK_CANTONESE

        && hkl != CHS_HKL) {

        dwRet[0] = dwRet[1] = 0;

        return dwRet[uIndex];

    }

    if (ImmGetIMEFileNameA(hkl, szTemp, sizeof(szTemp) - 1) <= 0) {

        dwRet[0] = dwRet[1] = 0;

        return dwRet[uIndex];

    }

    if (!videodata->GetReadingString) {

        #define LCID_INVARIANT MAKELCID(MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US), SORT_DEFAULT)

        if (CompareStringA(LCID_INVARIANT, NORM_IGNORECASE, szTemp, -1, CHT_IMEFILENAME1, -1) != 2

            && CompareStringA(LCID_INVARIANT, NORM_IGNORECASE, szTemp, -1, CHT_IMEFILENAME2, -1) != 2

            && CompareStringA(LCID_INVARIANT, NORM_IGNORECASE, szTemp, -1, CHT_IMEFILENAME3, -1) != 2

            && CompareStringA(LCID_INVARIANT, NORM_IGNORECASE, szTemp, -1, CHS_IMEFILENAME1, -1) != 2

            && CompareStringA(LCID_INVARIANT, NORM_IGNORECASE, szTemp, -1, CHS_IMEFILENAME2, -1) != 2) {

            dwRet[0] = dwRet[1] = 0;

            return dwRet[uIndex];

        }

        #undef LCID_INVARIANT

        dwVerSize = GetFileVersionInfoSizeA(szTemp, &dwVerHandle);

        if (dwVerSize) {

            lpVerBuffer = SDL_malloc(dwVerSize);

            if (lpVerBuffer) {

                if (GetFileVersionInfoA(szTemp, dwVerHandle, dwVerSize, lpVerBuffer)) {

                    if (VerQueryValueA(lpVerBuffer, "\\", &lpVerData, &cbVerData)) {

                        #define pVerFixedInfo   ((VS_FIXEDFILEINFO FAR*)lpVerData)

                        DWORD dwVer = pVerFixedInfo->dwFileVersionMS;

                        dwVer = (dwVer & 0x00ff0000) << 8 | (dwVer & 0x000000ff) << 16;

                        if ((videodata->GetReadingString) ||

                            ((dwLang == LANG_CHT) && (

                            dwVer == MAKEIMEVERSION(4, 2) ||

                            dwVer == MAKEIMEVERSION(4, 3) ||

                            dwVer == MAKEIMEVERSION(4, 4) ||

                            dwVer == MAKEIMEVERSION(5, 0) ||

                            dwVer == MAKEIMEVERSION(5, 1) ||

                            dwVer == MAKEIMEVERSION(5, 2) ||

                            dwVer == MAKEIMEVERSION(6, 0)))

                            ||

                            ((dwLang == LANG_CHS) && (

                            dwVer == MAKEIMEVERSION(4, 1) ||

                            dwVer == MAKEIMEVERSION(4, 2) ||

                            dwVer == MAKEIMEVERSION(5, 3)))) {

                            dwRet[0] = dwVer | dwLang;

                            dwRet[1] = pVerFixedInfo->dwFileVersionLS;

                            SDL_free(lpVerBuffer);

                            return dwRet[0];

                        }

                        #undef pVerFixedInfo

                    }

                }

            }

            SDL_free(lpVerBuffer);

        }

    }

    dwRet[0] = dwRet[1] = 0;

    return dwRet[uIndex];

}

static void

IME_SetupAPI(SDL_VideoData *videodata)

{

    char ime_file[MAX_PATH + 1];

    void* hime = 0;

    HKL hkl = 0;

    videodata->GetReadingString = 0;

    videodata->ShowReadingWindow = 0;

    if (videodata->ime_uiless)

        return;

    hkl = videodata->ime_hkl;

    if (ImmGetIMEFileNameA(hkl, ime_file, sizeof(ime_file) - 1) <= 0)

        return;

    hime = SDL_LoadObject(ime_file);

    if (!hime)

        return;

    videodata->GetReadingString = (UINT (WINAPI *)(HIMC, UINT, LPWSTR, PINT, BOOL*, PUINT))

        SDL_LoadFunction(hime, "GetReadingString");

    videodata->ShowReadingWindow = (BOOL (WINAPI *)(HIMC, BOOL))

        SDL_LoadFunction(hime, "ShowReadingWindow");

    if (videodata->ShowReadingWindow) {

        HIMC himc = ImmGetContext(videodata->ime_hwnd_current);

        if (himc) {

            videodata->ShowReadingWindow(himc, FALSE);

            ImmReleaseContext(videodata->ime_hwnd_current, himc);

        }

    }

}

static void

IME_SetWindow(SDL_VideoData* videodata, HWND hwnd)

{

    videodata->ime_hwnd_current = hwnd;

    if (videodata->ime_threadmgr) {

        struct ITfDocumentMgr *document_mgr = 0;

        if (SUCCEEDED(videodata->ime_threadmgr->lpVtbl->AssociateFocus(videodata->ime_threadmgr, hwnd, NULL, &document_mgr))) {

            if (document_mgr)

                document_mgr->lpVtbl->Release(document_mgr);

        }

    }

}

static void

IME_UpdateInputLocale(SDL_VideoData *videodata)

{

    static HKL hklprev = 0;

    videodata->ime_hkl = GetKeyboardLayout(0);

    if (hklprev == videodata->ime_hkl)

        return;

    hklprev = videodata->ime_hkl;

    switch (PRIMLANG()) {

    case LANG_CHINESE:

        videodata->ime_candvertical = SDL_TRUE;

        if (SUBLANG() == SUBLANG_CHINESE_SIMPLIFIED)

            videodata->ime_candvertical = SDL_FALSE;

        break;

    case LANG_JAPANESE:

        videodata->ime_candvertical = SDL_TRUE;

        break;

    case LANG_KOREAN:

        videodata->ime_candvertical = SDL_FALSE;

        break;

    }

}

static void

IME_ClearComposition(SDL_VideoData *videodata)

{

    HIMC himc = 0;

    if (!videodata->ime_initialized)

        return;

    himc = ImmGetContext(videodata->ime_hwnd_current);

    if (!himc)

        return;

    ImmNotifyIME(himc, NI_COMPOSITIONSTR, CPS_CANCEL, 0);

    if (videodata->ime_uiless)

        ImmSetCompositionString(himc, SCS_SETSTR, TEXT(""), sizeof(TCHAR), TEXT(""), sizeof(TCHAR));

    ImmNotifyIME(himc, NI_CLOSECANDIDATE, 0, 0);

    ImmReleaseContext(videodata->ime_hwnd_current, himc);

    SDL_SendEditingText("", 0, 0);

}

static void

IME_GetCompositionString(SDL_VideoData *videodata, HIMC himc, DWORD string)

{

    LONG length = ImmGetCompositionStringW(himc, string, videodata->ime_composition, sizeof(videodata->ime_composition));

    if (length < 0)

        length = 0;

    length /= sizeof(videodata->ime_composition[0]);

    videodata->ime_cursor = LOWORD(ImmGetCompositionStringW(himc, GCS_CURSORPOS, 0, 0));

    if (videodata->ime_composition[videodata->ime_cursor] == 0x3000) {

        int i;

        for (i = videodata->ime_cursor + 1; i < length; ++i)

            videodata->ime_composition[i - 1] = videodata->ime_composition[i];

        --length;

    }

    videodata->ime_composition[length] = 0;

}

static void

IME_SendInputEvent(SDL_VideoData *videodata)

{

    char *s = 0;

    s = WIN_StringToUTF8(videodata->ime_composition);

    SDL_SendKeyboardText(s);

    SDL_free(s);

    videodata->ime_composition[0] = 0;

    videodata->ime_readingstring[0] = 0;

    videodata->ime_cursor = 0;

}

static void

IME_SendEditingEvent(SDL_VideoData *videodata)

{

    char *s = 0;

    WCHAR buffer[SDL_TEXTEDITINGEVENT_TEXT_SIZE];

    buffer[0] = 0;

    if (videodata->ime_readingstring[0]) {

        size_t len = SDL_min(SDL_wcslen(videodata->ime_composition), (size_t)videodata->ime_cursor);

        SDL_wcslcpy(buffer, videodata->ime_composition, len + 1);

        SDL_wcslcat(buffer, videodata->ime_readingstring, sizeof(buffer));

        SDL_wcslcat(buffer, &videodata->ime_composition[len], sizeof(buffer) - len);

    }

    else {

        SDL_wcslcpy(buffer, videodata->ime_composition, sizeof(videodata->ime_composition));

    }

    s = WIN_StringToUTF8(buffer);

    SDL_SendEditingText(s, videodata->ime_cursor + SDL_wcslen(videodata->ime_readingstring), 0);

    SDL_free(s);

}

static void

IME_AddCandidate(SDL_VideoData *videodata, UINT i, LPCWSTR candidate)

{

    LPWSTR dst = videodata->ime_candidates[i];

    *dst++ = (WCHAR)(TEXT('0') + ((i + videodata->ime_candlistindexbase) % 10));

    if (videodata->ime_candvertical)

        *dst++ = TEXT(' ');

    while (*candidate && (SDL_arraysize(videodata->ime_candidates[i]) > (dst - videodata->ime_candidates[i])))

        *dst++ = *candidate++;

    *dst = (WCHAR)'\0';

}

static void

IME_GetCandidateList(HIMC himc, SDL_VideoData *videodata)

{

    LPCANDIDATELIST cand_list = 0;

    DWORD size = ImmGetCandidateListW(himc, 0, 0, 0);

    if (size) {

        cand_list = (LPCANDIDATELIST)SDL_malloc(size);

        if (cand_list) {

            size = ImmGetCandidateListW(himc, 0, cand_list, size);

            if (size) {

                int i = 0;

                int j = 0;

                int page_start = 0;

                videodata->ime_candsel = cand_list->dwSelection;

                videodata->ime_candcount = cand_list->dwCount;

                if (LANG() == LANG_CHS && IME_GetId(videodata, 0)) {

                    const UINT maxcandchar = 18;

                    UINT i = 0;

                    UINT cchars = 0;

                    for (; i < videodata->ime_candcount; ++i) {

                        UINT len = SDL_wcslen((LPWSTR)((DWORD_PTR)cand_list + cand_list->dwOffset[i])) + 1;

                        if (len + cchars > maxcandchar) {

                            if (i > cand_list->dwSelection)

                                break;

                            page_start = i;

                            cchars = len;

                        }

                        else {

                            cchars += len;

                        }

                    }

                    videodata->ime_candpgsize = i - page_start;

                }

                else {

                    videodata->ime_candpgsize = SDL_min(cand_list->dwPageSize, MAX_CANDLIST);

                    page_start = (cand_list->dwSelection / videodata->ime_candpgsize) * videodata->ime_candpgsize;

                }

                SDL_memset(&videodata->ime_candidates, 0, sizeof(videodata->ime_candidates));

                for (i = page_start, j = 0; (DWORD)i < cand_list->dwCount && j < (int)videodata->ime_candpgsize; i++, j++) {

                    LPCWSTR candidate = (LPCWSTR)((DWORD_PTR)cand_list + cand_list->dwOffset[i]);

                    IME_AddCandidate(videodata, j, candidate);

                }

                if (PRIMLANG() == LANG_KOREAN || (PRIMLANG() == LANG_CHT && !IME_GetId(videodata, 0)))

                    videodata->ime_candsel = -1;

            }

            SDL_free(cand_list);

        }

    }

}

static void

IME_ShowCandidateList(SDL_VideoData *videodata)

{

    videodata->ime_dirty = SDL_TRUE;

    videodata->ime_candlist = SDL_TRUE;

    IME_DestroyTextures(videodata);

    IME_SendEditingEvent(videodata);

}

static void

IME_HideCandidateList(SDL_VideoData *videodata)

{

    videodata->ime_dirty = SDL_FALSE;

    videodata->ime_candlist = SDL_FALSE;

    IME_DestroyTextures(videodata);

    IME_SendEditingEvent(videodata);

}

SDL_bool

IME_HandleMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM *lParam, SDL_VideoData *videodata)

{

    SDL_bool trap = SDL_FALSE;

    HIMC himc = 0;

    if (!videodata->ime_initialized || !videodata->ime_available || !videodata->ime_enabled)

        return SDL_FALSE;

    switch (msg) {

    case WM_INPUTLANGCHANGE:

        IME_InputLangChanged(videodata);

        break;

    case WM_IME_SETCONTEXT:

        *lParam = 0;

        break;

    case WM_IME_STARTCOMPOSITION:

        trap = SDL_TRUE;

        break;

    case WM_IME_COMPOSITION:

        trap = SDL_TRUE;

        himc = ImmGetContext(hwnd);

        if (*lParam & GCS_RESULTSTR) {

            IME_GetCompositionString(videodata, himc, GCS_RESULTSTR);

            IME_SendInputEvent(videodata);

        }

        if (*lParam & GCS_COMPSTR) {

            if (!videodata->ime_uiless)

                videodata->ime_readingstring[0] = 0;

            IME_GetCompositionString(videodata, himc, GCS_COMPSTR);

            IME_SendEditingEvent(videodata);

        }

        ImmReleaseContext(hwnd, himc);

        break;

    case WM_IME_ENDCOMPOSITION:

        videodata->ime_composition[0] = 0;

        videodata->ime_readingstring[0] = 0;

        videodata->ime_cursor = 0;

        SDL_SendEditingText("", 0, 0);

        break;

    case WM_IME_NOTIFY:

        switch (wParam) {

        case IMN_SETCONVERSIONMODE:

        case IMN_SETOPENSTATUS:

            IME_UpdateInputLocale(videodata);

            break;

        case IMN_OPENCANDIDATE:

        case IMN_CHANGECANDIDATE:

            if (videodata->ime_uiless)

                break;

            trap = SDL_TRUE;

            IME_ShowCandidateList(videodata);

            himc = ImmGetContext(hwnd);

            if (!himc)

                break;

            IME_GetCandidateList(himc, videodata);

            ImmReleaseContext(hwnd, himc);

            break;

        case IMN_CLOSECANDIDATE:

            trap = SDL_TRUE;

            IME_HideCandidateList(videodata);

            break;

        case IMN_PRIVATE:

            {

                DWORD dwId = IME_GetId(videodata, 0);

                IME_GetReadingString(videodata, hwnd);

                switch (dwId)

                {

                case IMEID_CHT_VER42:

                case IMEID_CHT_VER43:

                case IMEID_CHT_VER44:

                case IMEID_CHS_VER41:

                case IMEID_CHS_VER42:

                    if (*lParam == 1 || *lParam == 2)

                        trap = SDL_TRUE;

                    break;

                case IMEID_CHT_VER50:

                case IMEID_CHT_VER51:

                case IMEID_CHT_VER52:

                case IMEID_CHT_VER60:

                case IMEID_CHS_VER53:

                    if (*lParam == 16

                        || *lParam == 17

                        || *lParam == 26

                        || *lParam == 27

                        || *lParam == 28)

                        trap = SDL_TRUE;

                    break;

                }

            }

            break;

        default:

            trap = SDL_TRUE;

            break;

        }

        break;

    }

    return trap;

}

static void

IME_CloseCandidateList(SDL_VideoData *videodata)

{

    IME_HideCandidateList(videodata);

    videodata->ime_candcount = 0;

    SDL_memset(videodata->ime_candidates, 0, sizeof(videodata->ime_candidates));

}

static void

UILess_GetCandidateList(SDL_VideoData *videodata, ITfCandidateListUIElement *pcandlist)

{

    UINT selection = 0;

    UINT count = 0;

    UINT page = 0;

    UINT pgcount = 0;

    DWORD pgstart = 0;

    DWORD pgsize = 0;

    UINT i, j;

    pcandlist->lpVtbl->GetSelection(pcandlist, &selection);

    pcandlist->lpVtbl->GetCount(pcandlist, &count);

    pcandlist->lpVtbl->GetCurrentPage(pcandlist, &page);

    videodata->ime_candsel = selection;

    videodata->ime_candcount = count;

    IME_ShowCandidateList(videodata);

    pcandlist->lpVtbl->GetPageIndex(pcandlist, 0, 0, &pgcount);

    if (pgcount > 0) {

        UINT *idxlist = SDL_malloc(sizeof(UINT) * pgcount);

        if (idxlist) {

            pcandlist->lpVtbl->GetPageIndex(pcandlist, idxlist, pgcount, &pgcount);

            pgstart = idxlist[page];

            if (page < pgcount - 1)

                pgsize = SDL_min(count, idxlist[page + 1]) - pgstart;