module wavmetrics

  ! new: Thu Jan  4 00:08:04 UTC 2024

  use mathstuff2
  implicit none

  type wavmetric
    integer             :: nbre             ! number of slices/samples
    real                :: freql, freqr     ! zero-crossing estimation
    integer             :: maxl,  maxr      ! maximum of abs values
    real                :: meanl, meanr
  end type

  type intsample
    integer             :: left, right
  end type

  contains
!-------------------------------------------------------------
!-
!        main computation routine, still full buggy
!-
subroutine compute_wavmetric(samples, size, metrics)
  type(intsample), intent(in)       :: samples(:)
  integer, intent(in)               :: size
  type(wavmetric), intent(out)      :: metrics

  integer                           :: Lmax, Rmax
  integer                           :: Lval, Rval
  integer                           :: idx
  integer                           :: Lfreq, Rfreq

  real                              :: Lsum, Rsum

  Lmax  = 0     ;   Rmax  = 0
  Lfreq = 1     ;   Rfreq = 1
  Lsum  = 0.0   ;   Rsum  = 0.0

  do idx=1, size
    Lval = samples(idx)%left
    Rval = samples(idx)%right

    ! print *, Rval, Lval
    if (abs(Lval) .GT. Lmax)   Lmax = abs(Lval)
    if (abs(Rval) .GT. Rmax)   Rmax = abs(Rval)

    if (idx .GT. 1) then
      if (diff_sign(samples(idx-1)%left,  Lval))  Lfreq = Lfreq + 1
      if (diff_sign(samples(idx-1)%right, Lval))  Rfreq = Rfreq + 1
    endif

    Lsum = Lsum + Lval
    Rsum = Rsum + Rval

  enddo

  metrics%num   = size
  metrics%maxl  = Lmax   ;  metrics%maxr = Rmax
  metrics%freql = 1.0 / (Lfreq / real(size))
  metrics%freqr = 1.0 / (Rfreq / real(size))
  metrics%meanl = Lsum / real(size)
  metrics%meanr = Rsum / real(size)

end subroutine

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

subroutine display_wavmetrics(metrics)
  type(wavmetric), intent(in)      :: metrics

  ! print '(1X, "metrics are :")'

  print '(1X, "    | num          ", I0)',     metrics%num
  print '(1X, "    | freq         ", 2F12.2)', metrics%freql, metrics%freqr
  print '(1X, "    | mean         ", 2F12.2)', metrics%meanl, metrics%meanr
  print '(1X, "    | maxi         ", 2I8)',    metrics%maxl, metrics%maxr

end subroutine

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

end module