#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     | Website:  https://openfoam.org
#   \\  /    A nd           | Copyright (C) 2015-2026 OpenFOAM Foundation
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM.
#
#     OpenFOAM is free software: you can redistribute it and/or modify it
#     under the terms of the GNU General Public License as published by
#     the Free Software Foundation, either version 3 of the License, or
#     (at your option) any later version.
#
#     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
#     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
#     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
#     for more details.
#
#     You should have received a copy of the GNU General Public License
#     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
#
# Script
#     foamNewSolver
#
# Description
#     Create directory of source and compilation files for a new solver
#
#------------------------------------------------------------------------------
Script=${0##*/}
dir="$FOAM_ETC/codeTemplates/solver"

usage() {
    cat<<USAGE

Usage: $Script [OPTIONS] <parentSolverName> <solverName>
options:
  -help  | -h         print the usage

Create directory of source and compilation files for a new solver
<solverName>, derived from <parentSolverName>
  - .C and .H source files
  - Make (dir)
    - files
    - options
  Compiles a library named lib<solverName>.so in \$FOAM_USER_LIBBIN:
  $FOAM_USER_LIBBIN

Example:
   foamNewSolver fluid myFluid

USAGE
    exit 1
}

error() {
    while [ "$#" -ge 1 ]; do echo "Error: $1"; shift; done
    usage
    exit 1
}

while [ "$#" -gt 0 ]
do
   case "$1" in
   -h | -help)
      usage && exit 0
      ;;
   -*)
      error "invalid option '$1'"
      ;;
   *)
      break
      ;;
    esac
done

[ "$#" -eq 2 ] || error "Wrong number of arguments"

parent=$1
name=$2
year=$(date +%Y)

solvers="$(foamToC -table solver \
             | sed '1,/Contents/d' \
             | awk '{print $1}' \
             | xargs)"

# Check parent solver exists
echo "${solvers}" \
    | grep -q "${parent}" \
    || error "Parent solver '${parent}' not found"

# Check name is different to parent
[ "$name" = "$parent" ] \
    && error "Solver name: '${name}' already exists"

# Prevent over-writing of existing directory
[ -d "$name" ] && error "$name directory already exists, aborting..."
echo "Creating $name directory" && mkdir "$name"

# Establish solver template files to copy
files=$(find "${dir}" -name "*.*" -type f -exec basename {} \;)

# Make substitutions in solver template files
for f in $files
do
    fName="${f%%.*}"
    ext=".${f##*.}"
    [ "${f}" = SOLVER.C ] || [ "${f}" = SOLVER.H ] && fName="${name}"

    echo "   Adding file ${fName}${ext}..."

    file="${name}"/"${fName}${ext}"

    sed -e "s#NAME#${name}#g" \
        -e "s#PARENT#${parent}#g" \
        -e "s#YEAR#${year}#g" \
        "${dir}"/"${f}" > "$file"

    tmpfile="$(mktemp "/tmp/${0##*/}.XXXXXX")"

    while read -r line
    do
        [ "${#line}" -gt 80 ] && echo "$line" >> "$tmpfile"
    done < "$file"

    while read -r line
    do
        comment=""
        [ "$(echo "$line" | cut -c1-2)" = // ] && comment=//
        sed -i "s@\(${line%::*}::\)\(${line##*::}\)@\1\n$comment\2@" "$file"
    done < "$tmpfile"
done

# Make substitutions in Make/files
echo "Creating Make subdirectory" && mkdir "${name}/Make"
sed -e "s#NAME#${name}#g" \
    -e "s#PARENT#${parent}#g" \
    "${dir}/Make/files" > "${name}/Make/files"

# Add parent header to Make/options
sed -e "/EXE_INC/a\    -I\$(FOAM_MODULES)/${parent}/lnInclude \\\\" \
    "${FOAM_MODULES}/${parent}/Make/options" \
    > "${name}/Make/options"

# Change local paths to global paths
# shellcheck disable=SC2016
sed -i '/-I/{/-I\$/!s/-I/-I\$(FOAM_MODULES)\/'"${parent}"'\//g}' \
    "${name}/Make/options"

# Add parent lib to Make/options
lib="${parent}"
echo "${lib}" | grep -q "Solver$" || lib="${lib}Solver"
sed -i "/LIB_LIBS/a\    -l${lib} \\\\" \
    "${name}/Make/options"