Unicode True
!include "LogicLib.nsh"

Var defaultInstallDir

!macro preInit

    IfFileExists "D:\*.*" DDriveExists CDriveDefault
    
    CDriveDefault:
        StrCpy $defaultInstallDir "$PROGRAMFILES\${APP_ID}"
        Goto doneDetect
    
    DDriveExists:
        StrCpy $defaultInstallDir "D:\${APP_ID}"
    
    doneDetect:

    StrCpy $INSTDIR "$defaultInstallDir"

!macroend

!macro init
    ${If} $INSTDIR == ""
        StrCpy $INSTDIR "$defaultInstallDir"
    ${EndIf}
!macroend


!insertmacro preInit
!insertmacro init

Section "MainSection" SEC01
    CreateDirectory "$INSTDIR"
    SetRegView 64
    WriteRegStr HKLM "${INSTALL_REGISTRY_KEY}" "InstallLocation" "$INSTDIR"
    WriteRegStr HKCU "${INSTALL_REGISTRY_KEY}" "InstallLocation" "$INSTDIR"
    SetRegView 32
    WriteRegStr HKLM "${INSTALL_REGISTRY_KEY}" "InstallLocation" "$INSTDIR"
    WriteRegStr HKCU "${INSTALL_REGISTRY_KEY}" "InstallLocation" "$INSTDIR"
SectionEnd

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