#!/bin/sh
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | www.openfoam.com
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
#     Copyright (C) 2018-2022 OpenCFD Ltd.
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
#
# Script
#     tools/lib-dir [OPTION] DIR [LIBEXT]
#
# Description
#     Since csh/tcsh doesn't have functions, this script can be used to manage
#     slightly more complex logic.
#
#     Resolves for the existence of DIR/lib64 and DIR/lib, or uses the fallback
#     LIBEXT if these failed. A DIR ending in "-none" or "-system" is skipped.
#
#     output -csh:     setenv LD_LIBRARY_PATH dir/lib:$LD_LIBRARY_PATH
#     output -sh:      LD_LIBRARY_PATH=dir/lib:$LD_LIBRARY_PATH
#     output -make:    -Ldir/lib
#
# Note
#     LD_LIBRARY_PATH automatically changes to DYLD_LIBRARY_PATH for Darwin.
#
# Environment
#     WM_COMPILER_LIB_ARCH
#
#------------------------------------------------------------------------------
printHelp() {
    cat<<USAGE

Usage: ${0##*/} [OPTION] DIR [LIBEXT]

options:
  -sh               Emit POSIX shell syntax (default)
  -csh              Emit C-shell shell syntax
  -sh-verbose       Like -sh,  with additional verbosity
  -csh-verbose      Like -csh, with additional verbosity
  -make             Emit content for a Makefile
  -help             Print the usage

Resolves for the existence of DIR/lib64 and DIR/lib, or uses the fallback
LIBEXT if these failed. A DIR ending in "-none" or "-system" is skipped.

With -sh             LD_LIBRARY_PATH=dir/lib:\$LD_LIBRARY_PATH
With -csh            setenv LD_LIBRARY_PATH dir/lib:\$LD_LIBRARY_PATH
With -make           -Ldir/lib

Exit status is zero (success) or non-zero (failure)
USAGE
    exit 0  # A clean exit
}

# Report error and exit
die()
{
    exec 1>&2
    echo
    echo "Error encountered:"
    while [ "$#" -ge 1 ]; do echo "    $1"; shift; done
    echo
    echo "See '${0##*/} -help' for usage"
    echo
    exit 1
}


#------------------------------------------------------------------------------

optSyntax="sh"
unset verboseOutput

# Parse options
while [ "$#" -gt 0 ]
do
    case "$1" in
    -h | -help*)
        printHelp
        ;;
    -csh | -sh | -make)
        optSyntax="${1#-}"
        unset verboseOutput
        ;;
    -csh-verbose | -sh-verbose)
        optSyntax="${1#-}"
        verboseOutput="source "         # Report: "export/setenv ..."
        ;;
    --)
        shift
        break
        ;;
    -*)
        die "unknown option: '$1'"
        ;;
    *)
        break
        ;;
    esac
    shift
done

#------------------------------------------------------------------------------

dir="$1"   # $1 = base directory for 'lib' or 'lib64'
alt="$2"   # $2 = fallback libname ('lib' or 'lib64')

unset resolved

# 0)
# Skip entirely if directory ends in "-none" or "-system".
# These special cases (disabled, system directories) should not require
# adjustment of LD_LIBRARY_PATH

case "$dir" in
none |  system  | *-none | *-system)
    unset dir
    ;;
esac

if [ -z "$dir" ]
then
    exit 1
elif [ -d "$dir" ]
then
    # 1) Check for dir/lib64 and dir/lib
    for end in lib$WM_COMPILER_LIB_ARCH lib
    do
        if [ -d "$dir/$end" ]
        then
            resolved=$dir/$end
            break
        fi
    done
fi

# 2) Use fallback if the previous failed
if [ -z "$resolved" ] && [ -n "$alt" ]
then
    # Fallback
    case "$alt" in
    /*)
        resolved="$alt"
        ;;
    (*)
        resolved="$dir/$alt"
        ;;
    esac
    exit 0
fi


if [ -n "$resolved" ]
then
    case "$optSyntax-$(uname -s 2>/dev/null)" in
    make*)
        printf "%s\n" "-L$resolved"
        ;;
    csh-Darwin*)
        echo "setenv DYLD_LIBRARY_PATH $resolved:$DYLD_LIBRARY_PATH"
        if [ -n "$verboseOutput" ]
        then
            echo "setenv DYLD_LIBRARY_PATH $resolved:$DYLD_LIBRARY_PATH" 1>&2
        fi
        ;;
    csh*)
        echo "setenv LD_LIBRARY_PATH $resolved:$LD_LIBRARY_PATH"
        if [ -n "$verboseOutput" ]
        then
            echo "setenv LD_LIBRARY_PATH $resolved:$LD_LIBRARY_PATH" 1>&2
        fi
        ;;
    sh-Darwin*)
        echo "DYLD_LIBRARY_PATH=$resolved:$DYLD_LIBRARY_PATH"
        if [ -n "$verboseOutput" ]
        then
            echo "DYLD_LIBRARY_PATH=$resolved:$DYLD_LIBRARY_PATH" 1>&2
        fi
        ;;
    *)
        # Default is -sh
        echo "LD_LIBRARY_PATH=$resolved:$LD_LIBRARY_PATH"
        if [ -n "$verboseOutput" ]
        then
            echo "LD_LIBRARY_PATH=$resolved:$LD_LIBRARY_PATH" 1>&2
        fi
        ;;
    esac
    exit 0      # Good
else
    exit 1      # Error
fi


#------------------------------------------------------------------------------