[IMM32] Rewrite ImmSetActiveContext (#3982)

- Re-implement ImmSetActiveContext function.
- Modify NtUserNotifyIMEStatus prototype.
- Improve ImmSetConversionStatus and ImmSetOpenStatus functions.
CORE-11700

dll/win32/imm32/ime.c

@@ -911,7 +911,7 @@ BOOL WINAPI ImmSetOpenStatus(HIMC hIMC, BOOL fOpen)
     {
         Imm32NotifyAction(hIMC, hWnd, NI_CONTEXTUPDATED, 0,
                           IMC_SETOPENSTATUS, IMN_SETOPENSTATUS, 0);
-        NtUserNotifyIMEStatus(hWnd, hIMC, dwConversion);
+        NtUserNotifyIMEStatus(hWnd, fOpen, dwConversion);
     }
 
     return TRUE;
@@ -1346,7 +1346,7 @@ BOOL WINAPI ImmSetConversionStatus(HIMC hIMC, DWORD fdwConversion, DWORD fdwSent
     HKL hKL;
     LPINPUTCONTEXT pIC;
     DWORD dwOldConversion, dwOldSentence;
-    BOOL fConversionChange = FALSE, fSentenceChange = FALSE, fUseCicero = FALSE;
+    BOOL fOpen = FALSE, fConversionChange = FALSE, fSentenceChange = FALSE, fUseCicero = FALSE;
     HWND hWnd;
 
     TRACE("(%p, 0x%lX, 0x%lX)\n", hIMC, fdwConversion, fdwSentence);
@@ -1377,6 +1377,7 @@ BOOL WINAPI ImmSetConversionStatus(HIMC hIMC, DWORD fdwConversion, DWORD fdwSent
     }
 
     hWnd = pIC->hWnd;
+    fOpen = pIC->fOpen;
     ImmUnlockIMC(hIMC);
 
     if (fConversionChange || fUseCicero)
@@ -1384,7 +1385,7 @@ BOOL WINAPI ImmSetConversionStatus(HIMC hIMC, DWORD fdwConversion, DWORD fdwSent
         Imm32NotifyAction(hIMC, hWnd, NI_CONTEXTUPDATED, dwOldConversion,
                           IMC_SETCONVERSIONMODE, IMN_SETCONVERSIONMODE, 0);
         if (fConversionChange)
-            NtUserNotifyIMEStatus(hWnd, hIMC, fdwConversion);
+            NtUserNotifyIMEStatus(hWnd, fOpen, fdwConversion);
     }
 
     if (fSentenceChange || fUseCicero)

dll/win32/imm32/imm.c

@@ -169,6 +169,11 @@ static InputContextData* get_imc_data(HIMC hIMC)
     return data;
 }
 
+static VOID APIENTRY Imm32CiceroSetActiveContext(HIMC hIMC, BOOL fActive, HWND hWnd, HKL hKL)
+{
+    FIXME("We have to do something\n");
+}
+
 /***********************************************************************
  *		ImmAssociateContext (IMM32.@)
  */
@@ -1314,10 +1319,96 @@ BOOL WINAPI ImmEnumInputContext(DWORD dwThreadId, IMCENUMPROC lpfn, LPARAM lPara
 /***********************************************************************
  *              ImmSetActiveContext(IMM32.@)
  */
-BOOL WINAPI ImmSetActiveContext(HWND hwnd, HIMC hIMC, BOOL fFlag)
+BOOL WINAPI ImmSetActiveContext(HWND hWnd, HIMC hIMC, BOOL fActive)
 {
-    FIXME("(%p, %p, %d): stub\n", hwnd, hIMC, fFlag);
+    PCLIENTIMC pClientImc;
-    return FALSE;
+    LPINPUTCONTEXTDX pIC;
+    PIMEDPI pImeDpi;
+    HKL hKL;
+    BOOL fOpen = FALSE;
+    DWORD dwConversion = 0, iShow = ISC_SHOWUIALL;
+    HWND hwndDefIME;
+
+    TRACE("(%p, %p, %d)\n", hWnd, hIMC, fActive);
+
+    if (!Imm32IsImmMode())
+        return FALSE;
+
+    pClientImc = ImmLockClientImc(hIMC);
+
+    if (!fActive)
+    {
+        if (pClientImc)
+            pClientImc->dwFlags &= ~CLIENTIMC_UNKNOWN4;
+    }
+    else if (hIMC)
+    {
+        if (!pClientImc)
+            return FALSE;
+
+        pIC = (LPINPUTCONTEXTDX)ImmLockIMC(hIMC);
+        if (!pIC)
+        {
+            ImmUnlockClientImc(pClientImc);
+            return FALSE;
+        }
+
+        pIC->hWnd = hWnd;
+        pClientImc->dwFlags |= CLIENTIMC_UNKNOWN5;
+
+        if (pIC->dwUIFlags & 2)
+            iShow = (ISC_SHOWUIGUIDELINE | ISC_SHOWUIALLCANDIDATEWINDOW);
+
+        fOpen = pIC->fOpen;
+        dwConversion = pIC->fdwConversion;
+
+        ImmUnlockIMC(hIMC);
+    }
+    else
+    {
+        hIMC = Imm32GetContextEx(hWnd, TRUE);
+        pIC = (LPINPUTCONTEXTDX)ImmLockIMC(hIMC);
+        if (pIC)
+        {
+            pIC->hWnd = hWnd;
+            ImmUnlockIMC(hIMC);
+        }
+        hIMC = NULL;
+    }
+
+    hKL = GetKeyboardLayout(0);
+
+    if (Imm32IsCiceroMode() && !Imm32Is16BitMode())
+    {
+        Imm32CiceroSetActiveContext(hIMC, fActive, hWnd, hKL);
+        hKL = GetKeyboardLayout(0);
+    }
+
+    pImeDpi = ImmLockImeDpi(hKL);
+    if (pImeDpi)
+    {
+        if (IS_IME_HKL(hKL))
+            pImeDpi->ImeSetActiveContext(hIMC, fActive);
+        ImmUnlockImeDpi(pImeDpi);
+    }
+
+    if (IsWindow(hWnd))
+    {
+        SendMessageW(hWnd, WM_IME_SETCONTEXT, fActive, iShow);
+        if (fActive)
+            NtUserNotifyIMEStatus(hWnd, fOpen, dwConversion);
+    }
+    else if (!fActive)
+    {
+        hwndDefIME = ImmGetDefaultIMEWnd(NULL);
+        if (hwndDefIME)
+            SendMessageW(hwndDefIME, WM_IME_SETCONTEXT, 0, iShow);
+    }
+
+    if (pClientImc)
+        ImmUnlockClientImc(pClientImc);
+
+    return TRUE;
 }
 
 /***********************************************************************

win32ss/include/ntuser.h

@@ -1312,6 +1312,8 @@ C_ASSERT(sizeof(CLIENTIMC) == 0x34);
 
 /* flags for CLIENTIMC */
 #define CLIENTIMC_WIDE 0x1
+#define CLIENTIMC_UNKNOWN5 0x2
+#define CLIENTIMC_UNKNOWN4 0x20
 #define CLIENTIMC_UNKNOWN1 0x40
 #define CLIENTIMC_UNKNOWN3 0x80
 #define CLIENTIMC_UNKNOWN2 0x100
@@ -2769,10 +2771,7 @@ NtUserMoveWindow(
 
 DWORD
 NTAPI
-NtUserNotifyIMEStatus(
+NtUserNotifyIMEStatus(HWND hwnd, BOOL fOpen, DWORD dwConversion);
-    HWND hwnd,
-    HIMC hIMC,
-    DWORD dwConversion);
 
 BOOL
 NTAPI

win32ss/user/ntuser/ime.c

@@ -49,16 +49,12 @@ NtUserGetImeHotKey(IN DWORD dwHotKey,
 
 DWORD
 APIENTRY
-NtUserNotifyIMEStatus(
+NtUserNotifyIMEStatus(HWND hwnd, BOOL fOpen, DWORD dwConversion)
-    HWND hwnd,
-    HIMC hIMC,
-    DWORD dwConversion)
 {
-    TRACE("NtUserNotifyIMEStatus(%p, %p, 0x%lX)\n", hwnd, hIMC, dwConversion);
+    TRACE("NtUserNotifyIMEStatus(%p, %d, 0x%lX)\n", hwnd, fOpen, dwConversion);
     return 0;
 }
 
-
 DWORD
 APIENTRY
 NtUserSetImeHotKey(