module config

use, intrinsic :: iso_fortran_env, only : stderr=>error_unit, compiler_version

use pathlib, only : expanduser, get_suffix, make_absolute

use phys_consts, only : wp

implicit none (type, external)

private

public :: read_configfile, gemini_cfg, get_compiler_vendor

type :: gemini_cfg

!> basic simulation information (base)

integer, dimension(3) :: ymd0

real(wp) :: UTsec0, tdur, dtout

real(wp) :: activ(3)

real(wp) :: tcfl

real(wp) :: Teinf

integer :: potsolve,flagperiodic,flagoutput

logical :: nooutput = .false.

logical :: dryrun = .false.

!> file information (files)

character(:), allocatable :: infile,outdir,indatsize,indatgrid,indatfile,out_format, &

fieldpointfile

character(:), allocatable :: git_revision

!> neutral atmospheric perturbations

integer :: flagdneu ! whether or not to include neutral perturbations from input files

character(:), allocatable :: sourcedir ! where the neutral input files are located

integer :: interptype=0 ! assumptions to be used when interpolating neutrals: 0-cartesian 2D, 1-axisymmetric 2D, 3 - cartesian 3D

real(wp) :: sourcemlat=0,sourcemlon=0 ! source latitude and longitude

real(wp) :: dtneu=0 ! time step between neutral inputs

real(wp) :: dxn=0,drhon=0,dzn=0 ! dx,dy (or drho),dz for neutral inputs

!> preciptiation file inputs

integer :: flagprecfile ! whether or not we have precipitation input from a file

character(:), allocatable :: precdir ! location of precipitation input data

real(wp) :: dtprec=0 ! time step between precipitation inputs

!> electric field file inputs

integer :: flagE0file ! whether or not to have electric field file input

character(:), allocatable :: E0dir ! location of electric field input data

real(wp) :: dtE0=0 ! time step between electric field inputs

!> GLOW parameters

integer :: flagglow ! whether or not to use glow to compute impact ionization

real(wp) :: dtglow, dtglowout ! time step between GLOW updates and outputs for GLOW emissions

integer :: flag_fang=2008 !< configure Fang ionization model

!! parameters below this line can only be changed via the .nml input format

!> equatorial ionization anomaly

logical :: flagEIA=.false. ! whether or not to include and equatorial ionization anomaly in simulation

real(wp) :: v0equator=10._wp ! max vertical drift of plasma at equator for EIA

!> varying neutral atmosphere background

logical :: flagneuBG=.false. ! whether or not to allow MSIS to be called to update neutral background

real(wp) :: dtneuBG=900._wp ! approximate time between MSIS calls

integer :: msis_version

!> background preciptation

real(wp) :: PhiWBG=1e-3_wp ! background total energy flux in mW/m^2

real(wp) :: W0BG=3e3_wp ! background characteristic energy for precipitation

!> parallel current calculations

logical :: flagJpar=.true. ! whether or not to compute parallel current (some simulation setups will give really poor results); code ignores this if potential is resolved along the field line since computing Jpar will not be prone to artifacts as it is in th EFL cases...

!> inertial capacitance

integer :: flagcap = 0 ! use inertial capacitance? 0 - set all to zero, 1 - use ionosphere to compute, 2 - add a magnetospheric part

real(wp) :: magcap=5._wp ! value of integrated magnetospheric capacitance to use

!> type of diffusion solver to sue

integer :: diffsolvetype=2 ! 1 - first order backward Euler time stepping; 2 - 2nd order TRBDF2 diffusion solver

!> milestone output information (default to none, i.e. zero value)

integer :: mcadence=-1 ! value less than zero switches this off, > zero gives the cadence at which to perform milestone outputs (in terms of number of outputs per milestone)

!> gravitational drift terms

logical :: flaggravdrift=.false.

!> flag for lagrangian grid (assume drifting at E x B/B**2)

logical :: flaglagrangian=.false.

!> do we consider pressure terms in perp momentum equations

logical :: flagdiamagnetic=.false.

end type gemini_cfg

interface

module subroutine read_nml(cfg, verbose)

class(gemini_cfg), intent(inout) :: cfg

logical, intent(in), optional :: verbose

end subroutine read_nml

module subroutine read_ini(cfg)

class(gemini_cfg), intent(inout) :: cfg

end subroutine read_ini

end interface

contains

subroutine read_configfile(cfg, verbose)

!! READS THE INPUT CONFIGURAITON FILE, ASSIGNS VARIABLES FOR FILENAMES, SIZES, ETC.

class(gemini_cfg), intent(inout) :: cfg

logical, intent(in), optional :: verbose

integer :: i, realbits, lxp, lyp

real(wp) :: NaN, glat, glon, xdist, ydist, alt_min, alt_max, alt_scale(4), Bincl, nmf, nme

character(:), allocatable :: suffix

!> READ CONFIG FILE FOR THIS SIMULATION

!! NOTE: Namelist file groups must be read in order they appear in the Namelist file, or End of File error occurs

suffix = get_suffix(cfg%infile)

select case (suffix)

case ('.nml')

call read_nml(cfg, verbose)

case ('.ini')

call read_ini(cfg)

case default

error stop 'not sure how to read config file ' // cfg%infile

end select

end subroutine read_configfile

character(5) function get_compiler_vendor() result(vendor)

character(80) :: cvers

integer :: i, j

character(*), parameter :: vendors(2) = [character(5) :: "Intel", "GCC"]

cvers = compiler_version()

do j = 1,size(vendors)

vendor = vendors(j)

i = index(cvers, vendor)

if (i > 0) exit

end do

if(vendor=="GCC") then

vendor = "GNU"

elseif(i == 0) then

vendor = ""

write(stderr,'(A,/,A)') "could not determine compiler vendor from",cvers

end if

end function get_compiler_vendor

end module config