! Conformal Cubic Atmospheric Model
    
! Copyright 2015 Commonwealth Scientific Industrial Research Organisation (CSIRO)
    
! This file is part of the Conformal Cubic Atmospheric Model (CCAM)
!
! CCAM is free software: you can redistribute it and/or modify
! it under the terms of the GNU General Public License as published by
! the Free Software Foundation, either version 3 of the License, or
! (at your option) any later version.
!
! CCAM is distributed in the hope that it will be useful,
! but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
! GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License
! along with CCAM.  If not, see <http://www.gnu.org/licenses/>.

!------------------------------------------------------------------------------
    
module checkver_m

! This module provides a routine to check version numbers of library modules.
! The version number must be a public character parameter in the module
! for this to work.
! The assumption is that the major version number will be increased
! whenever there is a change in the interface.

   implicit none

contains

   subroutine checkver ( name, revision, major_req, minor_req )
      character(len=*), intent(in) :: name
      character(len=*), intent(in) :: revision
      integer, intent(in) :: major_req
      integer, intent(in), optional :: minor_req
      integer :: start, end, major, minor

!     Routine gives an error unless library module major version number 
!     is equal to the requested value. If the minor argument is given, the
!     library minor version number must be greater than or equal to the 
!     requested value.

!     Parse the module revision string      
!     Major number comes after :
      start=index(revision,"Revision:")
      if ( start == 0 ) then
         print*, " Error in checkver. Failed to parse argument ", &
                 trim(revision)
      end if
      end = index(revision,".")
      if ( end == 0 ) then
         print*, " Error in checkver. Failed to parse argument ", &
                 trim(revision)
      end if
      read ( revision(start+9:end-1),* ) major
      start = end+1
      read ( revision(start:len(revision)),* ) minor

      if ( major_req /= major ) then
         print*, " CHECKVER ERROR: ", trim(name), " ", trim(revision), &
                 " Requested major version", major_req
         stop
      end if
      if ( present(minor_req) ) then
         if ( minor_req > minor ) then
            print*, " CHECKVER ERROR: ", trim(name), " ", trim(revision), &
                    " Requested minor version", minor_req
            stop
         end if
      end if

   end subroutine checkver
end module checkver_m