/*
_____________________________________________________________________________

                       File Association
_____________________________________________________________________________

 Based on code taken from http://nsis.sourceforge.net/File_Association

 Usage in script:
 1. !include "FileAssociation.nsh"
 2. [Section|Function]
      ${FileAssociationFunction} "Param1" "Param2" "..." $var
    [SectionEnd|FunctionEnd]

 FileAssociationFunction=[RegisterExtension|UnRegisterExtension]

_____________________________________________________________________________

 ${RegisterExtension} "[executable]" "[extension]" "[description]"

"[executable]"     ; executable which opens the file format
                   ;
"[extension]"      ; extension, which represents the file format to open
                   ;
"[description]"    ; description for the extension. This will be display in Windows Explorer.
                   ;


 ${UnRegisterExtension} "[extension]" "[description]"

"[extension]"      ; extension, which represents the file format to open
                   ;
"[description]"    ; description for the extension. This will be display in Windows Explorer.
                   ;

_____________________________________________________________________________

                         Macros
_____________________________________________________________________________

 Change log window verbosity (default: 3=no script)

 Example:
 !include "FileAssociation.nsh"
 !insertmacro RegisterExtension
 ${FileAssociation_VERBOSE} 4   # all verbosity
 !insertmacro UnRegisterExtension
 ${FileAssociation_VERBOSE} 3   # no script
*/


!ifndef FileAssociation_INCLUDED
!define FileAssociation_INCLUDED

!include Util.nsh

!verbose push
!verbose 3
!ifndef _FileAssociation_VERBOSE
  !define _FileAssociation_VERBOSE 3
!endif
!verbose ${_FileAssociation_VERBOSE}
!define FileAssociation_VERBOSE `!insertmacro FileAssociation_VERBOSE`
!verbose pop

!macro FileAssociation_VERBOSE _VERBOSE
  !verbose push
  !verbose 3
  !undef _FileAssociation_VERBOSE
  !define _FileAssociation_VERBOSE ${_VERBOSE}
  !verbose pop
!macroend



!macro RegisterExtensionCall _EXECUTABLE _EXTENSION _DESCRIPTION
  !verbose push
  !verbose ${_FileAssociation_VERBOSE}
  Push `${_DESCRIPTION}`
  Push `${_EXTENSION}`
  Push `${_EXECUTABLE}`
  ${CallArtificialFunction} RegisterExtension_
  !verbose pop
!macroend

!macro UnRegisterExtensionCall _EXTENSION _DESCRIPTION
  !verbose push
  !verbose ${_FileAssociation_VERBOSE}
  Push `${_EXTENSION}`
  Push `${_DESCRIPTION}`
  ${CallArtificialFunction} UnRegisterExtension_
  !verbose pop
!macroend



!define RegisterExtension `!insertmacro RegisterExtensionCall`
!define un.RegisterExtension `!insertmacro RegisterExtensionCall`

!macro RegisterExtension
!macroend

!macro un.RegisterExtension
!macroend

!macro RegisterExtension_
  !verbose push
  !verbose ${_FileAssociation_VERBOSE}

  Exch $R2 ;exe
  Exch
  Exch $R1 ;ext
  Exch
  Exch 2
  Exch $R0 ;desc
  Exch 2
  Push $0
  Push $1

  ReadRegStr $1 HKCR $R1 ""  ; read current file association
  StrCmp "$1" "" NoBackup  ; is it empty
  StrCmp "$1" "$R0" NoBackup  ; is it our own
    WriteRegStr HKCR $R1 "backup_val" "$1"  ; backup current value
NoBackup:
  WriteRegStr HKCR $R1 "" "$R0"  ; set our file association

  ReadRegStr $0 HKCR $R0 ""
  StrCmp $0 "" 0 Skip
    WriteRegStr HKCR "$R0" "" "$R0"
    WriteRegStr HKCR "$R0\shell" "" "open"
    WriteRegStr HKCR "$R0\DefaultIcon" "" "$R2,0"
Skip:
  WriteRegStr HKCR "$R0\shell\open\command" "" '"$R2" "%1"'
  WriteRegStr HKCR "$R0\shell\edit" "" "Edit $R0"
  WriteRegStr HKCR "$R0\shell\edit\command" "" '"$R2" "%1"'

  Pop $1
  Pop $0
  Pop $R2
  Pop $R1
  Pop $R0

  !verbose pop
!macroend



!define UnRegisterExtension `!insertmacro UnRegisterExtensionCall`
!define un.UnRegisterExtension `!insertmacro UnRegisterExtensionCall`

!macro UnRegisterExtension
!macroend

!macro un.UnRegisterExtension
!macroend

!macro UnRegisterExtension_
  !verbose push
  !verbose ${_FileAssociation_VERBOSE}

  Exch $R1 ;desc
  Exch
  Exch $R0 ;ext
  Exch
  Push $0
  Push $1

  ReadRegStr $1 HKCR $R0 ""
  StrCmp $1 $R1 0 NoOwn ; only do this if we own it
  ReadRegStr $1 HKCR $R0 "backup_val"
  StrCmp $1 "" 0 Restore ; if backup="" then delete the whole key
  DeleteRegKey HKCR $R0
  Goto NoOwn

Restore:
  WriteRegStr HKCR $R0 "" $1
  DeleteRegValue HKCR $R0 "backup_val"
  DeleteRegKey HKCR $R1 ;Delete key with association name settings

NoOwn:

  Pop $1
  Pop $0
  Pop $R1
  Pop $R0

  !verbose pop
!macroend

!endif # !FileAssociation_INCLUDED
