From fc75db49d370249537354138f16d82b94b5aa996 Mon Sep 17 00:00:00 2001
From: Matt Brubeck <mbrubeck@mozilla.com>
Date: Fri, 6 Dec 2013 13:09:31 -0800
Subject: [PATCH] Bug 946990 - Remember whether Metro or desktop Firefox was
 last used [r=bbondy]

---
 .../shell/commandexecutehandler/CEHHelper.cpp | 18 ++++
 .../shell/commandexecutehandler/CEHHelper.h   |  3 +
 .../CommandExecuteHandler.cpp                 | 91 +++++++------------
 3 files changed, 52 insertions(+), 60 deletions(-)

diff --git a/browser/metro/shell/commandexecutehandler/CEHHelper.cpp b/browser/metro/shell/commandexecutehandler/CEHHelper.cpp
index 163ca084af9..be7f0ac2377 100644
--- a/browser/metro/shell/commandexecutehandler/CEHHelper.cpp
+++ b/browser/metro/shell/commandexecutehandler/CEHHelper.cpp
@@ -12,6 +12,7 @@
 
 HANDLE sCon;
 LPCWSTR metroDX10Available = L"MetroD3DAvailable";
+LPCWSTR metroLastAHE = L"MetroLastAHE";
 
 typedef HRESULT (WINAPI*D3D10CreateDevice1Func)
   (IDXGIAdapter *, D3D10_DRIVER_TYPE, HMODULE, UINT,
@@ -107,6 +108,23 @@ IsProcessRunning(const wchar_t *processName, bool bCheckIfMetro)
   return exists;
 }
 
+
+AHE_TYPE
+GetLastAHE()
+{
+  DWORD ahe;
+  if (GetDWORDRegKey(metroLastAHE, ahe)) {
+    return (AHE_TYPE) ahe;
+  }
+  return AHE_DESKTOP;
+}
+
+bool
+SetLastAHE(AHE_TYPE ahe)
+{
+  return SetDWORDRegKey(metroLastAHE, (DWORD) ahe);
+}
+
 bool
 IsDX10Available()
 {
diff --git a/browser/metro/shell/commandexecutehandler/CEHHelper.h b/browser/metro/shell/commandexecutehandler/CEHHelper.h
index e30f1c5c210..3bd7bf8fef2 100644
--- a/browser/metro/shell/commandexecutehandler/CEHHelper.h
+++ b/browser/metro/shell/commandexecutehandler/CEHHelper.h
@@ -13,6 +13,7 @@
 #include <dxgi.h>
 #include <d3d10misc.h>
 #include <atlbase.h>
+#include <shlobj.h>
 
 //#define SHOW_CONSOLE 1
 extern HANDLE sCon;
@@ -24,6 +25,8 @@ void Log(const wchar_t *fmt, ...);
 void SetupConsole();
 #endif
 
+AHE_TYPE GetLastAHE();
+bool SetLastAHE(AHE_TYPE ahe);
 bool IsDX10Available();
 bool GetDWORDRegKey(LPCWSTR name, DWORD &value);
 bool SetDWORDRegKey(LPCWSTR name, DWORD value);
diff --git a/browser/metro/shell/commandexecutehandler/CommandExecuteHandler.cpp b/browser/metro/shell/commandexecutehandler/CommandExecuteHandler.cpp
index 910a0b124b2..d79ac85daff 100644
--- a/browser/metro/shell/commandexecutehandler/CommandExecuteHandler.cpp
+++ b/browser/metro/shell/commandexecutehandler/CommandExecuteHandler.cpp
@@ -262,79 +262,50 @@ public:
   IFACEMETHODIMP GetValue(AHE_TYPE *aLaunchType)
   {
     Log(L"IExecuteCommandApplicationHostEnvironment::GetValue()");
-    *aLaunchType = AHE_DESKTOP;
-    mIsDesktopRequest = true;
+    *aLaunchType = GetLaunchType();
+    mIsDesktopRequest = (*aLaunchType == AHE_DESKTOP);
+    SetLastAHE(*aLaunchType);
+    return S_OK;
+  }
+
+  /**
+   * Choose the appropriate launch type based on the user's previously chosen
+   * host environment, along with system constraints.
+   */
+  AHE_TYPE GetLaunchType() {
+    AHE_TYPE ahe = GetLastAHE();
+    Log(L"Previous AHE: %d", ahe);
 
     if (!mIsRestartMetroRequest && IsProcessRunning(kFirefoxExe, false)) {
-      return S_OK;
+      Log(L"Returning AHE_DESKTOP because desktop is already running");
+      return AHE_DESKTOP;
     } else if (!mIsRestartDesktopRequest && IsProcessRunning(kMetroFirefoxExe, true)) {
-      *aLaunchType = AHE_IMMERSIVE;
-      mIsDesktopRequest = false;
-      return S_OK;
-    }
-
-    if (!mUnkSite) {
-      Log(L"No mUnkSite.");
-      return S_OK;
+      Log(L"Returning AHE_IMMERSIVE because Metro is already running");
+      return AHE_IMMERSIVE;
     }
 
     if (mIsRestartDesktopRequest) {
       Log(L"Restarting in desktop host environment.");
-      return S_OK;
+      return AHE_DESKTOP;
     }
 
-    HRESULT hr;
-    IServiceProvider* pSvcProvider = nullptr;
-    hr = mUnkSite->QueryInterface(IID_IServiceProvider, (void**)&pSvcProvider);
-    if (!pSvcProvider) {
-      Log(L"Couldn't get IServiceProvider service from explorer. (%X)", hr);
-      return S_OK;
+    if (mIsRestartMetroRequest) {
+      Log(L"Restarting in metro host environment.");
+      ahe = AHE_IMMERSIVE;
     }
 
-    IExecuteCommandHost* pHost = nullptr;
-    // If we can't get this it's a conventional desktop launch
-    hr = pSvcProvider->QueryService(SID_ExecuteCommandHost,
-                                    IID_IExecuteCommandHost, (void**)&pHost);
-    if (!pHost) {
-      Log(L"Couldn't get IExecuteCommandHost service from explorer. (%X)", hr);
-      SafeRelease(&pSvcProvider);
-      return S_OK;
-    }
-    SafeRelease(&pSvcProvider);
+    if (ahe == AHE_IMMERSIVE) {
+      if (!IsDefaultBrowser()) {
+        Log(L"returning AHE_DESKTOP because we are not the default browser");
+        return AHE_DESKTOP;
+      }
 
-    EC_HOST_UI_MODE mode;
-    if (FAILED(pHost->GetUIMode(&mode))) {
-      Log(L"GetUIMode failed.");
-      SafeRelease(&pHost);
-      return S_OK;
+      if (!IsDX10Available()) {
+        Log(L"returning AHE_DESKTOP because DX10 is not available");
+        return AHE_DESKTOP;
+      }
     }
-
-    // 0 - launched from desktop
-    // 1 - ?
-    // 2 - launched from tile interface
-    Log(L"GetUIMode: %d", mode);
-
-    if (!IsDefaultBrowser()) {
-      mode = ECHUIM_DESKTOP;
-    }
-
-    if (mode == ECHUIM_DESKTOP) {
-      Log(L"returning AHE_DESKTOP");
-      SafeRelease(&pHost);
-      return S_OK;
-    }
-    SafeRelease(&pHost);
-
-    if (!IsDX10Available()) {
-      Log(L"returning AHE_DESKTOP because DX10 is not available");
-      *aLaunchType = AHE_DESKTOP;
-      mIsDesktopRequest = true;
-    } else {
-      Log(L"returning AHE_IMMERSIVE");
-      *aLaunchType = AHE_IMMERSIVE;
-      mIsDesktopRequest = false;
-    }
-    return S_OK;
+    return ahe;
   }
 
   /*