reconstruct_imin Subroutine

    subroutine reconstruct_imin(qp, scheme, bc)
      !< Reconstruct state at the IMIN boundary face with MUSCL scheme

      implicit none
      real(wp), dimension(-2:imx+2, -2:jmx+2, -2:kmx+2, 1:n_var), intent(in) :: qp
      type(schemetype), intent(in) :: scheme
      type(boundarytype), intent(in) :: bc
      integer :: i, j, k, l
      real(wp) :: psi1, psi2, fd, bd, r
      real(wp) :: kappa, phi

      phi = 1.0
      kappa = 1./3.
      switch_L=scheme%ilimiter_switch

      if (ppm_flag==1) then
        do l = 1, n_var
          if(l>=6) switch_L=scheme%itlimiter_switch
         do k = 1, kmx - 1
          do j = 1, jmx - 1
           do i = 1, 1 

            ! reconstruct first cell faces for ppm scheme
              fd = qp(i+1, j, k, l) - qp(i  , j, k, l)
              bd = qp(i  , j, k, l) - qp(i-1, j, k, l)

              r = fd / bd
              psi1 = max(0., min(2*r, (2 + r)/3., 2.))
              psi1 = (1 - (1 - psi1)*switch_L )
              r = bd / fd
              psi2 = max(0., min(2*r, (2 + r)/3., 2.))
              psi2 = (1 - (1 - psi2)*switch_L )

              ! right state of firsrt interior cell
              x_qp_left(i+1, j, k, l) = qp(i, j, k, l) + 0.25*phi* &
                  (((1.-kappa) * psi1 * bd) + ((1.+kappa) * psi2 * fd))

              ! left face of first interior cell
              x_qp_right(i, j, k, l) = qp(i, j, k, l) - 0.25*phi* &
                  (((1.+kappa) * psi1 * bd) + ((1.-kappa) * psi2 * fd))
              
           end do
          end do
         end do
        end do
      end if
      if(bc%imin_id==-8 .or. bc%imin_id==-9)then
         x_qp_left(1,1:jmx-1,1:kmx-1,1:n_var) = qp(0,1:jmx-1,1:kmx-1,1:n_var) 
        x_qp_right(1,1:jmx-1,1:kmx-1,1:n_var) = qp(0,1:jmx-1,1:kmx-1,1:n_var) 
      else
        ! right face of first ghost cell
        x_qp_left(1,1:jmx-1,1:kmx-1,1:n_var) = 0.5*(qp(0,1:jmx-1,1:kmx-1,1:n_var)&
                                                   +qp(1,1:jmx-1,1:kmx-1,1:n_var))
      end if

    end subroutine reconstruct_imin