# bash completion for GNU tar                              -*- shell-script -*-

_tar()
{
    local cur prev words cword split
    _init_completion -s || return

    local ext regex tar untar

    if [[ $cword -eq 1 ]]; then
        COMPREPLY=( $( compgen -W 'c t x u r d A' -- "$cur" ) )
        return 0
    fi

    local tars='@(@(tar|gem|spkg)?(.@(Z|[gx]z|bz?(2)|lzma))|t@([glx]z|bz?(2)))'

    case ${words[1]} in
        --*)
            ;;
        ?(-)*[cr]*f)
            if [[ $cword -eq 2 ]]; then
                ext='@(tar|gem|spkg)'
                case ${words[1]} in
                    *a*)    ext="$tars"         ;;
                    *z*)    ext='t?(ar.)gz'     ;;
                    *Z*)    ext='tar.Z'         ;;
                    *[jy]*) ext='t?(ar.)bz?(2)' ;;
                    *J*)    ext='t?(ar.)xz'     ;;
                esac
                _filedir $ext
            else
                _filedir
            fi
            return 0
            ;;
        +([^IZzJjy])f)
            ext="$tars"
            regex='\(\(tar\|gem\|spkg\)\(\.\(Z\|[gx]z\|bz2\?\|lzma\)\)\?\|t\([glx]z\|bz2\?\)\)'
            ;;
        *[Zz]*f)
            ext='@(t?(ar.)|gem.|spkg.)@(gz|Z)'
            regex='\(t\(ar\.\)\?\|gem\.\|spkg\.\)\(gz\|Z\)'
            ;;
        *[Ijy]*f)
            ext='@(@(t?(ar.)|gem.)bz?(2)|spkg)'
            regex='\(\(t\(ar\.\)\?\|gem\.\)bz2\?\|spkg\)'
            ;;
        *[J]*f)
            ext='@(t?(ar.)|gem.|spkg.)@(lz?(ma)|xz)'
            regex='\(t\(ar\.\)\?\|gem\.\|spkg\.\)\(lzma\|xz\)\?'
            ;;
        *)
            _filedir
            return 0
            ;;
    esac

    case $prev in
        *$ext)
            # complete on files in tar file
            #
            # get name of tar file from command line
            tar=$( sed -e 's/^.* \([^ ]*'$regex'\) .*$/\1/' <<<"${words[@]}" )
            # devise how to untar and list it
            untar=t${words[1]//[^IJzjyf]/}

            local IFS=$'\n'
            COMPREPLY=( $( compgen -W "$( printf '%s\n' $( tar $untar $tar \
                2>/dev/null ) )" -- "$cur" ) )
            return 0
            ;;
        -C|--directory)
            _filedir -d
            return 0
            ;;
        --atime-preserve)
            COMPREPLY=( $( compgen -W 'replace system' -- "$cur" ) )
            return 0
            ;;
        --group)
            COMPREPLY=( $( compgen -g -- "$cur" ) )
            return 0
            ;;
        --owner)
            COMPREPLY=( $( compgen -u -- "$cur" ) )
            return 0
            ;;
        -F|--info-script|--new-volume-script|--rmt-command|--rsh-command|\
        -I|--use-compress-program)
            compopt -o filenames
            COMPREPLY=( $( compgen -c -- "$cur" ) )
            return 0
            ;;
        --volno-file|--add-file|-T|--files-from|-X|--exclude-from|--index-file)
            _filedir
            return 0
            ;;
        -H|--format)
            COMPREPLY=( $( compgen -W 'gnu oldgnu pax posix ustar v7' \
                -- "$cur" ) )
            return 0
            ;;
        --quoting-style)
            COMPREPLY=( $( compgen -W 'literal shell shell-always c c-maybe
                escape locale clocale' -- "$cur" ) )
            return 0
            ;;
        --totals)
            COMPREPLY=( $( compgen -W 'SIGHUP SIGQUIT SIGINT SIGUSR1 SIGUSR2' \
                -- "$cur" ) )
            return 0
            ;;
        --occurrence|--sparse-version|--to-command|--mode|--mtime|\
        --tape-length|-b|--blocking-factor|--record-size|-V|--text|--backup|\
        --exclude|--exclude-tag*|-K|--starting-file|-N|--newer|--after-date|\
        --suffix|--strip-components|--transform|--xform|--checkpoint|\
        --checkpoint-action|--no-quote-chars|--quote-chars|--warnings)
            return 0
            ;;
    esac

    $split && return 0

    # file completion on relevant files
    _filedir "$ext"

    return 0
}
[ -n "${COMP_TAR_INTERNAL_PATHS:-}" ] && complete -F _tar -o dirnames tar ||
    complete -F _tar tar

# ex: ts=4 sw=4 et filetype=sh