!-----------------------------------------------------------------------
!-
!       test program for the project "gravity field"
!-
!-----------------------------------------------------------------------
program essai
  use realfield
  use spitpgm               ! XXX

  implicit none

  type(massbody)          :: planet
  integer                 :: foo
  character(len=100)      :: filename

  planet%posx   = 337.314
  planet%posy   = 164.666
  planet%mass   = 1e8
  planet%serial = 42

  do foo=0, 48
    write (filename, "(a, i5.5, a)") 'WS/', foo, '.pgm'
    call build_and_write_a_field(800, 600, planet, filename)
    planet%posx = planet%posx + 6.99
    planet%posy = planet%posy + 2.55
  enddo

  STOP 'YOLO'

contains
!-----------------------------------------------------------------------
!-
!   compute a field with only one body; and write pic file
!-
subroutine build_and_write_a_field(szx, szy, moon, fname)
  integer, intent(in)                :: szx, szy
  type(massbody), intent(in)         :: moon
  character(len=*), intent(in)       :: fname

  real                               :: maxi, mini
  integer                            :: errcode
  real,    dimension(:,:), allocatable  :: field
  integer, dimension(:,:), allocatable  :: greymap

  allocate(field(szx, szy), stat=errcode)

  call compute_a_field(field, moon)
  maxi = maxval(field)
  mini = minval(field)
  print *, "field: ", mini, maxi, maxi-mini

  allocate(greymap(szx, szy), stat=errcode)
  greymap = 65535
  ! convert from real value to 16 bits int values
  where (field < 65530.0)
    greymap = int(field)
  end where

  call spit_as_pgm_16(greymap, trim(fname))

  ! make valgrind happy
  deallocate(field)
  deallocate(greymap)

end subroutine

!-----------------------------------------------------------------------
!-----------------------------------------------------------------------

end program