# https://github.com/SimpleITK/SimpleITK/blob/master/CMake/FindMono.cmake

#
# A CMake Module for finding Mono.
#
# The following variables are set:
#   CSHARP_MONO_FOUND
#   CSHARP_MONO_COMPILER_${version} eg. "CSHARP_MONO_COMPILER_2.10.2"
#   CSHARP_MONO_INTERPRETOR_${version} eg. "CSHARP_MONO_INTERPRETOR_2.10.2"
#   CSHARP_MONO_VERSION eg. "2.10.2"
#   CSHARP_MONO_VERSIONS eg. "2.10.2, 2.6.7"
#
# Additional references can be found here:
#   http://www.mono-project.com/Main_Page
#   http://www.mono-project.com/CSharp_Compiler
#   http://mono-project.com/FAQ:_Technical (How can I tell where the Mono runtime is installed)
#
# This file is based on the work of GDCM:
#   http://gdcm.svn.sf.net/viewvc/gdcm/trunk/CMake/FindMono.cmake
# Copyright (c) 2006-2010 Mathieu Malaterre <mathieu.malaterre@gmail.com>
#

set( csharp_mono_valid 1 )
if( DEFINED CSHARP_MONO_FOUND )
  # The Mono compiler has already been found
  # It may have been reset by the user, verify it is correct
  if( NOT DEFINED CSHARP_MONO_COMPILER_${CSHARP_MONO_VERSION} )
    set( csharp_mono_version_user ${CSHARP_MONO_VERSION} )
    set( csharp_mono_valid 0 )
    set( CSHARP_MONO_FOUND 0 )
    set( CSHARP_MONO_VERSION "CSHARP_MONO_VERSION-NOTVALID" CACHE STRING "C# Mono compiler version, choices: ${CSHARP_MONO_VERSIONS}" FORCE )
    message( FATAL_ERROR "The C# Mono version '${csharp_mono_version_user}' is not valid. Please enter one of the following: ${CSHARP_MONO_VERSIONS}" )
  endif( NOT DEFINED CSHARP_MONO_COMPILER_${CSHARP_MONO_VERSION} )
endif( DEFINED CSHARP_MONO_FOUND )

unset( CSHARP_MONO_VERSIONS CACHE ) # Clear versions
if( WIN32 )
  # Search for Mono on Win32 systems
  # See http://mono-project.com/OldReleases and http://www.go-mono.com/mono-downloads/download.html
  set( csharp_mono_bin_dirs )
  set( csharp_mono_search_hints
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.11.2;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.9;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.8;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.7;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.6;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.5;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.4;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.3;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.2;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10.1;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.10;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.8;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.6.7;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.6.4;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.6.3;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.6.1;SdkInstallRoot]/bin"
    "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono\\2.6;SdkInstallRoot]/bin"
  )
  foreach( csharp_mono_search_hint ${csharp_mono_search_hints} )
    get_filename_component( csharp_mono_bin_dir "${csharp_mono_search_hint}" ABSOLUTE )
    if ( EXISTS "${csharp_mono_bin_dir}" )
      set( csharp_mono_bin_dirs ${csharp_mono_bin_dirs} ${csharp_mono_bin_dir} )
    endif ( EXISTS "${csharp_mono_bin_dir}" )
  endforeach( csharp_mono_search_hint )
  # TODO: Use HKLM_LOCAL_MACHINE\Software\Novell\Mono\DefaultCLR to specify default version
  # get_filename_component( test "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Novell\\Mono;DefaultCLR]" NAME )

  foreach ( csharp_mono_bin_dir ${csharp_mono_bin_dirs} )
    string( REPLACE "\\" "/" csharp_mono_bin_dir ${csharp_mono_bin_dir} )
    if (EXISTS "${csharp_mono_bin_dir}/dmcs.bat")
      set( csharp_mono_executable "${csharp_mono_bin_dir}/dmcs.bat")
    elseif (EXISTS "${csharp_mono_bin_dir}/gmcs.bat")
      set( csharp_mono_executable "${csharp_mono_bin_dir}/gmcs.bat")
    elseif (EXISTS "${csharp_mono_bin_dir}/mcs.bat")
      set( csharp_mono_executable "${csharp_mono_bin_dir}/mcs.bat")
    endif (EXISTS "${csharp_mono_bin_dir}/dmcs.bat")

    if( csharp_mono_valid )
      # Extract version number (eg. 2.10.2)
      string(REGEX MATCH "([0-9]*)([.])([0-9]*)([.]*)([0-9]*)" csharp_mono_version_temp ${csharp_mono_bin_dir})
      set( CSHARP_MONO_VERSION ${csharp_mono_version_temp} CACHE STRING "C# Mono compiler version" )
      mark_as_advanced( CSHARP_MONO_VERSION )

      # Add variable holding executable
      set( CSHARP_MONO_COMPILER_${csharp_mono_version_temp} ${csharp_mono_executable} CACHE STRING "C# Mono compiler ${csharp_mono_version_temp}" FORCE )
      mark_as_advanced( CSHARP_MONO_COMPILER_${csharp_mono_version_temp} )

      # Set interpreter
      if (EXISTS "${csharp_mono_bin_dir}/mono.exe")
        set( CSHARP_MONO_INTERPRETER_${csharp_mono_version_temp} "${csharp_mono_bin_dir}/mono.exe" CACHE STRING "C# Mono interpreter ${csharp_mono_version_temp}" FORCE )
        mark_as_advanced( CSHARP_MONO_INTERPRETER_${csharp_mono_version_temp} )
      endif (EXISTS "${csharp_mono_bin_dir}/mono.exe")
    endif( csharp_mono_valid )

    # Create a list of supported compiler versions
    if( NOT DEFINED CSHARP_MONO_VERSIONS )
      set( CSHARP_MONO_VERSIONS "${csharp_mono_version_temp}" CACHE STRING "Available C# Mono compiler versions" FORCE )
    else( NOT DEFINED CSHARP_MONO_VERSIONS )
      set( CSHARP_MONO_VERSIONS "${CSHARP_MONO_VERSIONS}, ${csharp_mono_version_temp}"  CACHE STRING "Available C# Mono versions" FORCE )
    endif( NOT DEFINED CSHARP_MONO_VERSIONS )
    mark_as_advanced( CSHARP_MONO_VERSIONS )

    # We found at least one Mono compiler version
    set( CSHARP_MONO_FOUND 1 CACHE INTERNAL "Boolean indicating if C# Mono was found" )
  endforeach( csharp_mono_bin_dir )

else( UNIX )
  # Search for Mono on non-Win32 systems
  set( chsarp_mono_names "mcs" "mcs.exe" "dmcs" "dmcs.exe" "smcs" "smcs.exe" "gmcs" "gmcs.exe" )
  set(
    csharp_mono_paths
    "/usr/bin/"
    "/usr/local/bin/"
    "/usr/lib/mono/2.0"
    "/opt/novell/mono/bin"
  )
  find_program(
    csharp_mono_compiler # variable is added to the cache, we removed it below
    NAMES ${chsarp_mono_names}
    PATHS ${csharp_mono_paths}
  )

  if( EXISTS ${csharp_mono_compiler} )
    # Determine version
    find_program(
      csharp_mono_interpreter # variable is added to the cache, we removed it below
      NAMES mono
      PATHS ${csharp_mono_paths}
    )
    if ( EXISTS ${csharp_mono_interpreter} )
      execute_process(
        COMMAND ${csharp_mono_interpreter} -V
        OUTPUT_VARIABLE csharp_mono_version_string
      )
      string( REGEX MATCH "([0-9]*)([.])([0-9]*)([.]*)([0-9]*)" csharp_mono_version_temp ${csharp_mono_version_string} )
      set( CSHARP_MONO_INTERPRETER_${CSHARP_MONO_VERSION} ${csharp_mono_interpreter} CACHE STRING "C# Mono interpreter ${csharp_mono_version_temp}" FORCE )
      mark_as_advanced( CSHARP_MONO_INTERPRETER_${CSHARP_MONO_VERSION} )
    endif ( EXISTS ${csharp_mono_interpreter} )
    unset( csharp_mono_interpreter CACHE )

    # We found Mono compiler
    set( CSHARP_MONO_VERSION ${csharp_mono_version_temp} CACHE STRING "C# Mono compiler version" )
    mark_as_advanced( CSHARP_MONO_VERSION )
    set( CSHARP_MONO_COMPILER_${CSHARP_MONO_VERSION} ${csharp_mono_compiler} CACHE STRING "C# Mono compiler ${CSHARP_MONO_VERSION}" FORCE )
    mark_as_advanced( CSHARP_MONO_COMPILER_${CSHARP_MONO_VERSION} )
    set( CSHARP_MONO_VERSIONS ${CSHARP_MONO_VERSION} CACHE STRING "Available C# Mono compiler versions" FORCE )
    mark_as_advanced( CSHARP_MONO_VERSIONS )
    set( CSHARP_MONO_FOUND 1 CACHE INTERNAL "Boolean indicating if C# Mono was found" )
  endif( EXISTS ${csharp_mono_compiler} )

  # Remove temp variable from cache
  unset( csharp_mono_compiler CACHE )

endif( WIN32 )

if( CSHARP_MONO_FOUND )
  # Report the found versions
  message( STATUS "Found the following C# Mono versions: ${CSHARP_MONO_VERSIONS}" )
endif( CSHARP_MONO_FOUND )

# Set USE_FILE
get_filename_component( current_list_path ${CMAKE_CURRENT_LIST_FILE} PATH )
set( Mono_USE_FILE ${current_list_path}/UseMono.cmake )
