Work around a common installation problem: the uninstaller window

takes a second to come up, and during that time it's possible to accidentally
start the new installation.  Wait for the uninstaller to finish, and check whether
it succeeded.

Now using NSIS 2.  The script assumes all previous versions are released
with 1.x, and all versions from here on in are 2.x.  This is extremely important,
since we have to work around an incompatible uninstaller change.

stepmania/stepmania.nsi

@@ -28,7 +28,7 @@ AutoCloseWindow true ; (can be true for the window go away automatically at end)
 SetDateSave on ; (can be on to have files restored to their orginal date)
 InstallDir "$PROGRAMFILES\${PRODUCT_ID}"
 InstallDirRegKey HKEY_LOCAL_MACHINE "SOFTWARE\StepMania\${PRODUCT_ID}" ""
-DirShow show ; (make this hide to not let the user change it)
+; DirShow show ; (make this hide to not let the user change it)
 DirText "${PRODUCT_NAME_VER}"
 
 
@@ -43,16 +43,52 @@ prompt_uninstall_vise:
 MessageBox MB_YESNO|MB_ICONINFORMATION "The previous version of StepMania must be uninstalled before continuing.$\nDo you wish to continue?" IDYES do_uninstall_vise
 Abort
 do_uninstall_vise:
-Exec '$WINDIR\unvise32.exe $INSTDIR\uninstal.log'	; don't use quotes here, or unvise32 will fail
+ExecWait '$WINDIR\unvise32.exe $INSTDIR\uninstal.log' $R1	; don't use quotes here, or unvise32 will fail
+
+; unvise32.exe doesn't return a useful exit code.  See if uninstal.log still exists.
+IfFileExists "$INSTDIR\uninstal.log" vise_still_exists old_vise_not_installed
+vise_still_exists:
+MessageBox MB_OK|MB_ICONINFORMATION "Uninstallation failed."
+Abort
+
 old_vise_not_installed:
 
 ; force uninstall of previous version using NSIS
-IfFileExists "$INSTDIR\uninst.exe" prompt_uninstall_nsis old_nsis_not_installed
+; We need to wait until the uninstaller finishes before continuing, since it's possible
+; to click the next button again before the uninstaller's window appears and takes focus.
+; This is tricky: we can't just ExecWait the uninstaller, since it copies off the uninstaller
+; EXE and exec's that (otherwise it couldn't delete itself), so it appears to exit immediately.
+; We need to copy it off ourself, run it with the hidden parameter to tell it it's a copy,
+; and then delete the copy ourself.  There's one more trick: the hidden parameter changed
+; between NSIS 1 and 2: in 1.x it was _=C:\Foo, in 2.x it's _?=C:\Foo.  Rename the installer
+; for newer versions, so we can tell the difference: "uninst.exe" is the old 1.x uninstaller,
+; "uninstall.exe" is 2.x.
+StrCpy $R1 "$INSTDIR\uninst.exe"
+StrCpy $R2 "_="
+IfFileExists "$R1" prompt_uninstall_nsis
+StrCpy $R1 "$INSTDIR\uninstall.exe"
+StrCpy $R2 "_?="
+IfFileExists "$R1" prompt_uninstall_nsis old_nsis_not_installed
+
 prompt_uninstall_nsis:
 MessageBox MB_YESNO|MB_ICONINFORMATION "The previous version of StepMania must be uninstalled before continuing.$\nDo you wish to continue?" IDYES do_uninstall_nsis
 Abort
+
 do_uninstall_nsis:
-Exec "$INSTDIR\uninst.exe"
+GetTempFileName $R3
+CopyFiles /SILENT $R1 $R3
+ExecWait '$R3 $R2$INSTDIR' $R4
+; Delete the copy of the installer.
+Delete $R3
+
+; $R4 is the exit value of the uninstaller.  0 means success, anything else is
+; failure (eg. aborted).
+IntCmp $R4 0 old_nsis_not_installed ; jump if 0
+
+MessageBox MB_OK|MB_ICONINFORMATION "Uninstallation failed."
+Abort
+
+
 old_nsis_not_installed:
 
 ; Check for DirectX 8.0 (to be moved to the right section later)
@@ -90,12 +126,12 @@ Section ""
 ; write out uninstaller
 SetOutPath "$INSTDIR"
 SetOverwrite on
-WriteUninstaller "$INSTDIR\uninst.exe"
+WriteUninstaller "$INSTDIR\uninstall.exe"
 
 ; add registry entries
 WriteRegStr HKEY_LOCAL_MACHINE "SOFTWARE\StepMania\${PRODUCT_ID}" "" "$INSTDIR"
 WriteRegStr HKEY_LOCAL_MACHINE "Software\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_ID}" "DisplayName" "${PRODUCT_ID} (remove only)"
-WriteRegStr HKEY_LOCAL_MACHINE "Software\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_ID}" "UninstallString" '"$INSTDIR\uninst.exe"'
+WriteRegStr HKEY_LOCAL_MACHINE "Software\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_ID}" "UninstallString" '"$INSTDIR\uninstall.exe"'
 
 WriteRegStr HKEY_LOCAL_MACHINE "SOFTWARE\Classes\Applications\smpackage.exe\shell\open\command" "" '"$INSTDIR\Program\smpackage.exe" "%1"'
 WriteRegStr HKEY_LOCAL_MACHINE "SOFTWARE\Classes\smzipfile" "" "SMZIP package"
@@ -238,7 +274,7 @@ CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\Open StepMania Program Folder.lnk" "$W
 CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\View Statistics.lnk" "$INSTDIR\Data\MachineProfile\stats.html"
 CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\StepMania Tools and Package Exporter.lnk" "$INSTDIR\Program\smpackage.exe"
 CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\README-FIRST.lnk" "$INSTDIR\README-FIRST.html"
-CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\Uninstall ${PRODUCT_NAME_VER}.lnk" "$INSTDIR\uninst.exe"
+CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\Uninstall ${PRODUCT_NAME_VER}.lnk" "$INSTDIR\uninstall.exe"
 CreateShortCut "$SMPROGRAMS\${PRODUCT_ID}\Go To StepMania web site.lnk" "http://www.stepmania.com"
 
 CreateShortCut "$INSTDIR\StepMania.lnk" "$INSTDIR\Program\stepmania.exe"
@@ -267,7 +303,7 @@ UninstallText "This will uninstall StepMania from your system.$\nAny add-on pack
 Section Uninstall
 
 ; add delete commands to delete whatever files/registry keys/etc you installed here.
-Delete "$INSTDIR\uninst.exe"
+Delete "$INSTDIR\uninstall.exe"
 DeleteRegKey HKEY_LOCAL_MACHINE "SOFTWARE\StepMania\${PRODUCT_ID}"
 DeleteRegKey HKEY_LOCAL_MACHINE "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_ID}"