# busctl(1) completion                               -*- shell-script -*-
# SPDX-License-Identifier: LGPL-2.1+
#
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# systemd 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 Lesser General Public License
# along with systemd; If not, see <http://www.gnu.org/licenses/>.

__contains_word () {
    local w word=$1; shift
    for w in "$@"; do
        [[ $w = "$word" ]] && return
    done
}

__get_machines() {
    local a b
    machinectl list --full --no-legend --no-pager 2>/dev/null |
        { while read a b; do echo " $a"; done; };
}

__get_busnames() {
    local mode=$1
    local a b
    busctl $mode list --no-legend --no-pager --full 2>/dev/null |
        { while read a b; do echo " $a"; done; };
}

__get_objects() {
    local mode=$1
    local busname=$2
    local a b
    busctl $mode tree --list --no-legend --no-pager $busname 2>/dev/null |
        { while read a b; do echo " $a"; done; };
}

__get_interfaces() {
    local mode=$1
    local busname=$2
    local path=$3
    local a b c
    busctl $mode introspect --list --no-legend --no-pager $busname $path 2>/dev/null |
        { while read a b c; do [[ "$b" == "interface" ]] && echo " $a"; done; };
}

__get_members() {
    local mode=$1
    local busname=$2
    local path=$3
    local interface=$4
    local type=$5
    local flags=$6
    local a b c d e
    busctl $mode introspect --list --no-legend --no-pager $busname $path $interface 2>/dev/null |
        sed -e 's/^\.//' |
        { while read a b c d e; do [[ "$b" == "$type" && ( -z $flags || "$e" == "$flags" ) ]] && echo " $a"; done; };
}

__get_signature() {
    local mode=$1
    local busname=$2
    local path=$3
    local interface=$4
    local member=$5
    local a b c d
    busctl $mode introspect --list --no-legend --no-pager $busname $path $interface 2>/dev/null |
        sed -e 's/^\.//' | { while read a b c d; do [[ "$a" == "$member" && "$c" != '-' ]] && echo " \"$c\""; done; };
}

_busctl() {
    local i n verb comps mode
    local cur=${COMP_WORDS[COMP_CWORD]} prev=${COMP_WORDS[COMP_CWORD-1]}
    local -A OPTS=(
        [STANDALONE]='-h --help --version --no-pager --no-legend --system --user
                      --show-machine --unique --acquired --activatable --list
                      -q --quiet --verbose --expect-reply=no --auto-start=no
                      --allow-interactive-authorization=no --augment-creds=no
                      --watch-bind=yes -j -l --full'
        [ARG]='--address -H --host -M --machine --match --timeout --size --json
                      --destination'
    )

    if __contains_word "--user" ${COMP_WORDS[*]}; then
        mode=--user
    else
        mode=--system
    fi

    if __contains_word "$prev" ${OPTS[ARG]}; then
        case $prev in
            --host|-H)
                comps=$(compgen -A hostname)
                ;;
            --machine|-M)
                comps=$( __get_machines )
                ;;
            --json)
                comps=$( busctl --json=help 2>/dev/null )
                ;;
            --destination)
                comps=$( __get_busnames $mode )
                ;;
        esac
        COMPREPLY=( $(compgen -W '$comps' -- "$cur") )
        return 0
    fi

    if [[ "$cur" = -* ]]; then
        COMPREPLY=( $(compgen -W '${OPTS[*]}' -- "$cur") )
        return 0
    fi

    local -A VERBS=(
        [STANDALONE]='list help'
        [BUSNAME]='status monitor capture tree'
        [OBJECT]='introspect'
        [METHOD]='call'
        [EMIT]='emit'
        [PROPERTY_GET]='get-property'
        [PROPERTY_SET]='set-property'
    )

    for ((i=0; i < COMP_CWORD; i++)); do
        if __contains_word "${COMP_WORDS[i]}" ${VERBS[*]} &&
                ! __contains_word "${COMP_WORDS[i-1]}" ${OPTS[ARG]}; then
            verb=${COMP_WORDS[i]}
            break
        fi
    done

    n=$(($COMP_CWORD - $i))

    if [[ -z $verb ]]; then
        comps=${VERBS[*]}
    elif __contains_word "$verb" ${VERBS[STANDALONE]}; then
        comps=''
    elif __contains_word "$verb" ${VERBS[BUSNAME]}; then
        comps=$( __get_busnames $mode)
    elif __contains_word "$verb" ${VERBS[OBJECT]}; then
        if [[ $n -eq 1 ]] ; then
            comps=$( __get_busnames $mode)
        elif [[ $n -eq 2 ]] ; then
            comps=$( __get_objects $mode ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 3 ]] ; then
            comps=$( __get_interfaces $mode ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        else
            comps=''
        fi
    elif __contains_word "$verb" ${VERBS[METHOD]}; then
        if [[ $n -eq 1 ]] ; then
            comps=$( __get_busnames $mode)
        elif [[ $n -eq 2 ]] ; then
            comps=$( __get_objects $mode ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 3 ]] ; then
            comps=$( __get_interfaces $mode ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 4 ]] ; then
            comps=$( __get_members $mode ${COMP_WORDS[COMP_CWORD-3]} ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]} method)
        elif [[ $n -eq 5 ]] ; then
            comps=$( __get_signature $mode ${COMP_WORDS[COMP_CWORD-4]} ${COMP_WORDS[COMP_CWORD-3]} ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        else
            comps=''
        fi
    elif __contains_word "$verb" ${VERBS[EMIT]}; then
        comps=''
    elif __contains_word "$verb" ${VERBS[PROPERTY_GET]}; then
        if [[ $n -eq 1 ]] ; then
            comps=$( __get_busnames $mode)
        elif [[ $n -eq 2 ]] ; then
            comps=$( __get_objects $mode ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 3 ]] ; then
            comps=$( __get_interfaces $mode ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 4 ]] ; then
            comps=$( __get_members $mode ${COMP_WORDS[COMP_CWORD-3]} ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]} property)
        else
            comps=''
        fi
    elif __contains_word "$verb" ${VERBS[PROPERTY_SET]}; then
        if [[ $n -eq 1 ]] ; then
            comps=$( __get_busnames $mode)
        elif [[ $n -eq 2 ]] ; then
            comps=$( __get_objects $mode ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 3 ]] ; then
            comps=$( __get_interfaces $mode ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        elif [[ $n -eq 4 ]] ; then
            comps=$( __get_members $mode ${COMP_WORDS[COMP_CWORD-3]} ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]} property writable)
        elif [[ $n -eq 5 ]] ; then
            comps=$( __get_signature $mode ${COMP_WORDS[COMP_CWORD-4]} ${COMP_WORDS[COMP_CWORD-3]} ${COMP_WORDS[COMP_CWORD-2]} ${COMP_WORDS[COMP_CWORD-1]})
        else
            comps=''
        fi
    fi

    COMPREPLY=( $(compgen -W '$comps' -- "$cur") )
    return 0
}

complete -F _busctl busctl
