INSTALL

#!/bin/bash
#
# FILE: INSTALL
#
# ABSTRACT: Install files to $HOME and $HOME/bin
#
# AUTHOR: Ralf Schandl
#

script_dir="$(cd "$(dirname "$0")" && pwd)"
script_name="$(basename "$0")"

cd "$script_dir" || exit 1

ts=$(date "+%Y-%m-%dT%H.%M.%S")
bin_target_dir="$HOME/bin"
completion_target_dir="$HOME/.local/share/bash-completion/completions"

execute()
{
    if [ "$execute" == "true" ]; then
        "$@"
    else
        echo "$@"
    fi
}

do_install()
{
    local fqfn="$1"
    local tgt="$2"

    if [ -e "$tgt" ]; then
        if [ "$mode" = "symlink" ] && [ -L "$tgt" ]; then
            tgtln="$(realpath "$tgt")"
            if [ "$fqfn" = "$tgtln" ]; then
                echo "Up-to-date: $tgt"
                return 0
            fi
        fi
        case "$exit_handling" in
            backup)
                # create backup copy
                echo "Backing up existing file: $tgt"
                execute mv "$tgt" "$tgt.$ts"
                ;;
            overwrite)
                # do nothing
                ;;
            *)
                echo >&2 "ERROR: File exists: $tgt"
                echo >&2 "       Use either '-b' or '-f'."
                echo >&2 ""
                usage
                ;;
        esac
    fi

    if [ "$mode" == "copy" ]; then
        echo "Copying $fqfn -> $tgt"
        execute cp -f "$fqfn" "$tgt"
    else
        echo "Linking $tgt -> $fqfn"
        execute ln -fs "$fqfn" "$tgt"
    fi
}



install_file()
{
    typeset fn="$1"
    typeset tgt_dir="$2"
    # shellcheck disable=SC2155
    typeset fqfn="$(realpath "$fn")"
    typeset tgt="$tgt_dir/$fn"

    do_install "$fqfn" "$tgt"
}

usage()
{
    echo >&2 "Usage: $script_name [-nfb] <copy|symlink>"
    echo >&2 "   -n  Just print what would be done."
    echo >&2 "   -f  force - overwrite existing files"
    echo >&2 "   -b  backup - backup existing files (with time stamp)"
    exit 1
}

#---------[ MAIN ]-------------------------------------------------------------

execute="true"
exit_handling=""
while getopts "nfb" o "$@"; do
    case $o in
        n) execute="false"
            ;;
        f) exit_handling="overwrite"
            ;;
        b) exit_handling="backup"
            ;;
        *)
            usage
            ;;
    esac
done
shift $((OPTIND-1))

if [ $# -ne 1 ]; then
    echo >&2 "ERROR: one argument needed"
    usage
fi

case "$1" in
    copy) mode="copy"
        ;;
    symlink) mode="symlink"
        ;;
    *) echo >&2 "Unknown mode: $1"
        usage
        ;;
esac

do_install "$script_dir/_maven-completion.bash" "$completion_target_dir/mvn"

if [ ! -d "$bin_target_dir" ]; then
    execute mkdir -p "$bin_target_dir"
fi

cd bin || exit 1
for fn in [!_]*[!~]; do
    if [ -f "$fn" ]; then
        install_file "$fn" "$bin_target_dir"
    fi
done