# bpftool(8) bash completion                               -*- shell-script -*-
#
# Copyright (C) 2017 Netronome Systems, Inc.
#
# This software is dual licensed under the GNU General License
# Version 2, June 1991 as shown in the file COPYING in the top-level
# directory of this source tree or the BSD 2-Clause License provided
# below.  You have the option to license this software under the
# complete terms of either license.
#
# The BSD 2-Clause License:
#
#     Redistribution and use in source and binary forms, with or
#     without modification, are permitted provided that the following
#     conditions are met:
#
#      1. Redistributions of source code must retain the above
#         copyright notice, this list of conditions and the following
#         disclaimer.
#
#      2. Redistributions in binary form must reproduce the above
#         copyright notice, this list of conditions and the following
#         disclaimer in the documentation and/or other materials
#         provided with the distribution.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#
# Author: Quentin Monnet <quentin.monnet@netronome.com>

# Takes a list of words in argument; each one of them is added to COMPREPLY if
# it is not already present on the command line. Returns no value.
_bpftool_once_attr()
{
    local w idx found
    for w in $*; do
        found=0
        for (( idx=3; idx < ${#words[@]}-1; idx++ )); do
            if [[ $w == ${words[idx]} ]]; then
                found=1
                break
            fi
        done
        [[ $found -eq 0 ]] && \
            COMPREPLY+=( $( compgen -W "$w" -- "$cur" ) )
    done
}

# Takes a list of words in argument; adds them all to COMPREPLY if none of them
# is already present on the command line. Returns no value.
_bpftool_one_of_list()
{
    local w idx
    for w in $*; do
        for (( idx=3; idx < ${#words[@]}-1; idx++ )); do
            [[ $w == ${words[idx]} ]] && return 1
        done
    done
    COMPREPLY+=( $( compgen -W "$*" -- "$cur" ) )
}

_bpftool_get_map_ids()
{
    COMPREPLY+=( $( compgen -W "$( bpftool -jp map  2>&1 | \
        command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ) )
}

_bpftool_get_prog_ids()
{
    COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \
        command sed -n 's/.*"id": \(.*\),$/\1/p' )" -- "$cur" ) )
}

_bpftool_get_prog_tags()
{
    COMPREPLY+=( $( compgen -W "$( bpftool -jp prog 2>&1 | \
        command sed -n 's/.*"tag": "\(.*\)",$/\1/p' )" -- "$cur" ) )
}

# For bpftool map update: retrieve type of the map to update.
_bpftool_map_update_map_type()
{
    local keyword ref
    for (( idx=3; idx < ${#words[@]}-1; idx++ )); do
        if [[ ${words[$((idx-2))]} == "update" ]]; then
            keyword=${words[$((idx-1))]}
            ref=${words[$((idx))]}
        fi
    done
    [[ -z $ref ]] && return 0

    local type
    type=$(bpftool -jp map show $keyword $ref | \
        command sed -n 's/.*"type": "\(.*\)",$/\1/p')
    printf $type
}

_bpftool_map_update_get_id()
{
    # Is it the map to update, or a map to insert into the map to update?
    # Search for "value" keyword.
    local idx value
    for (( idx=7; idx < ${#words[@]}-1; idx++ )); do
        if [[ ${words[idx]} == "value" ]]; then
            value=1
            break
        fi
    done
    [[ $value -eq 0 ]] && _bpftool_get_map_ids && return 0

    # Id to complete is for a value. It can be either prog id or map id. This
    # depends on the type of the map to update.
    local type=$(_bpftool_map_update_map_type)
    case $type in
        array_of_maps|hash_of_maps)
            _bpftool_get_map_ids
            return 0
            ;;
        prog_array)
            _bpftool_get_prog_ids
            return 0
            ;;
        *)
            return 0
            ;;
    esac
}

_bpftool()
{
    local cur prev words objword
    _init_completion || return

    # Deal with simplest keywords
    case $prev in
        help|key|opcodes)
            return 0
            ;;
        tag)
            _bpftool_get_prog_tags
            return 0
            ;;
        file|pinned)
            _filedir
            return 0
            ;;
        batch)
            COMPREPLY=( $( compgen -W 'file' -- "$cur" ) )
            return 0
            ;;
    esac

    # Search for object and command
    local object command cmdword
    for (( cmdword=1; cmdword < ${#words[@]}-1; cmdword++ )); do
        [[ -n $object ]] && command=${words[cmdword]} && break
        [[ ${words[cmdword]} != -* ]] && object=${words[cmdword]}
    done

    if [[ -z $object ]]; then
        case $cur in
            -*)
                local c='--version --json --pretty'
                COMPREPLY=( $( compgen -W "$c" -- "$cur" ) )
                return 0
                ;;
            *)
                COMPREPLY=( $( compgen -W "$( bpftool help 2>&1 | \
                    command sed \
                    -e '/OBJECT := /!d' \
                    -e 's/.*{//' \
                    -e 's/}.*//' \
                    -e 's/|//g' )" -- "$cur" ) )
                COMPREPLY+=( $( compgen -W 'batch help' -- "$cur" ) )
                return 0
                ;;
        esac
    fi

    [[ $command == help ]] && return 0

    # Completion depends on object and command in use
    case $object in
        prog)
            case $prev in
                id)
                    _bpftool_get_prog_ids
                    return 0
                    ;;
            esac

            local PROG_TYPE='id pinned tag'
            case $command in
                show)
                    [[ $prev != "$command" ]] && return 0
                    COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )
                    return 0
                    ;;
                dump)
                    case $prev in
                        $command)
                            COMPREPLY+=( $( compgen -W "xlated jited" -- \
                                "$cur" ) )
                            return 0
                            ;;
                        xlated|jited)
                            COMPREPLY=( $( compgen -W "$PROG_TYPE" -- \
                                "$cur" ) )
                            return 0
                            ;;
                    *)
                            _bpftool_once_attr 'file'
                            COMPREPLY+=( $( compgen -W 'opcodes' -- \
                                "$cur" ) )
                            return 0
                            ;;
                    esac
                    ;;
                pin)
                    if [[ $prev == "$command" ]]; then
                        COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )
                    else
                        _filedir
                    fi
                    return 0
                    ;;
                *)
                    [[ $prev == $object ]] && \
                        COMPREPLY=( $( compgen -W 'dump help pin show' -- \
                            "$cur" ) )
                    ;;
            esac
            ;;
        map)
            local MAP_TYPE='id pinned'
            case $command in
                show|dump)
                    case $prev in
                        $command)
                            COMPREPLY=( $( compgen -W "$MAP_TYPE" -- "$cur" ) )
                            return 0
                            ;;
                        id)
                            _bpftool_get_map_ids
                            return 0
                            ;;
                        *)
                            return 0
                            ;;
                    esac
                    ;;
                lookup|getnext|delete)
                    case $prev in
                        $command)
                            COMPREPLY=( $( compgen -W "$MAP_TYPE" -- "$cur" ) )
                            return 0
                            ;;
                        id)
                            _bpftool_get_map_ids
                            return 0
                            ;;
                        key)
                            return 0
                            ;;
                        *)
                            _bpftool_once_attr 'key'
                            return 0
                            ;;
                    esac
                    ;;
                update)
                    case $prev in
                        $command)
                            COMPREPLY=( $( compgen -W "$MAP_TYPE" -- "$cur" ) )
                            return 0
                            ;;
                        id)
                            _bpftool_map_update_get_id
                            return 0
                            ;;
                        key)
                            return 0
                            ;;
                        value)
                            # We can have bytes, or references to a prog or a
                            # map, depending on the type of the map to update.
                            case $(_bpftool_map_update_map_type) in
                                array_of_maps|hash_of_maps)
                                    local MAP_TYPE='id pinned'
                                    COMPREPLY+=( $( compgen -W "$MAP_TYPE" \
                                        -- "$cur" ) )
                                    return 0
                                    ;;
                                prog_array)
                                    local PROG_TYPE='id pinned tag'
                                    COMPREPLY+=( $( compgen -W "$PROG_TYPE" \
                                        -- "$cur" ) )
                                    return 0
                                    ;;
                                *)
                                    return 0
                                    ;;
                            esac
                            return 0
                            ;;
                        *)
                            _bpftool_once_attr 'key'
                            local UPDATE_FLAGS='any exist noexist'
                            for (( idx=3; idx < ${#words[@]}-1; idx++ )); do
                                if [[ ${words[idx]} == 'value' ]]; then
                                    # 'value' is present, but is not the last
                                    # word i.e. we can now have UPDATE_FLAGS.
                                    _bpftool_one_of_list "$UPDATE_FLAGS"
                                    return 0
                                fi
                            done
                            for (( idx=3; idx < ${#words[@]}-1; idx++ )); do
                                if [[ ${words[idx]} == 'key' ]]; then
                                    # 'key' is present, but is not the last
                                    # word i.e. we can now have 'value'.
                                    _bpftool_once_attr 'value'
                                    return 0
                                fi
                            done
                            return 0
                            ;;
                    esac
                    ;;
                pin)
                    if [[ $prev == "$command" ]]; then
                        COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )
                    else
                        _filedir
                    fi
                    return 0
                    ;;
                *)
                    [[ $prev == $object ]] && \
                        COMPREPLY=( $( compgen -W 'delete dump getnext help \
                            lookup pin show update' -- "$cur" ) )
                    ;;
            esac
            ;;
    esac
} &&
complete -F _bpftool bpftool

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