module moduleTableTtoZne
  use constantParameters, only: dp

  type:: tableTtoZne
    real(dp) :: Z_min, Z_max
    real(dp) :: Temp_min, Temp_max
    real(dp), allocatable, dimension(:):: Temp
    real(dp), allocatable, dimension(:,:):: Z
    real(dp), allocatable, dimension(:,:):: Z_k
    real(dp), allocatable, dimension(:):: ne
    contains
      procedure, pass:: init    => initTableTtoZne
      procedure, pass:: get     => getValueTableTtoZne

  end type tableTtoZne

  contains
    subroutine initTableTtoZne(self, tableFile)
      use constantParameters, only: eV_to_K
      use referenceValues, only: Temp_ref, n_ref
      implicit none

      class(tableTtoZne), intent(inout):: self
      character(:), allocatable, intent(in):: tableFile
      character(100):: dummy
      character(len=512) :: line
      character(len=20), allocatable :: ne_headers(:)
      integer:: amount, num_ne
      integer:: i,j
      integer:: stat
      integer:: id = 20
      num_ne = 0

      open(id, file = tableFile)
      amount = -1 ! Remove header
      do
        read(id, '(A)', iostat = stat) dummy
        !If EOF or error, exit file
        if (stat /= 0) EXIT
        ! !Skip comment
        ! if (index(dummy,'#') /= 0) CYCLE
        !Add row
        amount = amount + 1

      end do

      !Go bback to initial point
      rewind(id)
      read(id, '(A)', iostat = stat) dummy
      do i = 1, len_trim(dummy)
        if (dummy(i:i) ==  ",") num_ne = num_ne + 1
      end do
      allocate(ne_headers(num_ne))
      allocate(self%ne(num_ne))
      
      rewind(id)
      read(id, '(A)') line

      ! Read values while skipping the first entry
      read(line, *) dummy, (self%ne(i), i=1, num_ne)


      ! read(id, *)  ! Skip 'x'
      ! do i = 1, num_ne
      !   read(dummy, *) ne_headers(i)
      !   read(ne_headers(i), *) self%ne(i)
      !   print *, self%ne(i)
      ! end do
      rewind(id)
      

      !Allocate table arrays
      allocate(self%Temp(1:amount))
      allocate(self%Z(1:amount, 1:num_ne))
      allocate(self%Z_k(1:amount, 1:num_ne))
      self%Temp   = 0.0_dp
      self%Z      = 0.0_dp
      self%Z_k    = 0.0_dp

      i = 0
      read(id, *) ! Skip header
      do 
        read(id, '(A)', iostat = stat) dummy
        !TOdo: Make this a function
        if (stat /= 0) EXIT
        !Add data
        !TODO: substitute with extracting information from dummy
        backspace(id)
        i = i + 1
        read(id, *, iostat= stat) self%Temp(i), (self%Z(i, j), j = 1, num_ne)

      end do
      self%Temp = self%Temp * eV_to_K / Temp_ref
      self%ne = self%ne / n_ref

      close(id)

      self%Temp_min    = self%Temp(1)
      self%Temp_max    = self%Temp(amount)
      self%Z_min    = self%Z(1,1)
      self%Z_max    = self%Z(amount,num_ne)
      do i = 1, amount - 1
        do j = 1, num_ne 
          self%Z_k(i,j)    = (   self%Z(i+1,j) -    self%Z(i,j))/(self%Temp(i+1) - self%Temp(i))
        end do
      end do

    end subroutine initTableTtoZne

    subroutine getValueTableTtoZne(self, Temp, ne, Z)
      implicit none

      class(tableTtoZne), intent(in):: self
      real(dp), intent(in):: Temp, ne
      real(dp), intent(out):: Z
      real(dp):: delta_Temp
      integer:: i, j

      j = minloc(abs(ne - self%ne), 1)
      ! print *, "ne : ", ne
      !  print *, "Temp : ", Temp


      if     (Temp <= self%Temp_min) THEN
        Z   = self%Z_min

      elseif (Temp >= self%Temp_max) THEN
        Z    = self%Z_max

      else
        i = minloc(abs(Temp - self%Temp), 1)
        delta_Temp = Temp - self%Temp(i)
        if (delta_Temp < 0 ) THEN 
          i = i - 1
          delta_Temp = Temp - self%Temp(i)
          
        end if

        Z    =    self%Z(i,j) +    self%Z_k(i,j)*delta_Temp

      end if

    end subroutine getValueTableTtoZne



end module moduleTableTtoZne