#  OpenVPN 3 Linux client -- Next generation OpenVPN client
#
#  SPDX-License-Identifier: AGPL-3.0-only
#
#  Copyright (C) 2018 - 2023  OpenVPN Inc <sales@openvpn.net>
#  Copyright (C) 2018 - 2023  David Sommerseth <davids@openvpn.net>
#

##
# @file  bash_completion_openvpn3
#
# @brief  A bash_completion helper script for the openvpn3 command line
#         programs.  This script makes use of the shell-completion command
#         provided by openvpn3 or openvpn3-admin, which provides up-to-date
#         insight on the various commands, options and arguments.
#
#         Also works with zsh after loading bascomphinit
#         (autoload -U +X bashcompinit && bashcompinit)

_openvpn3_generic_completion()
{
    local cmd first cur prev opts base
    COMPREPLY=()
    cmd="$1"
    first=${COMP_WORDS[1]}
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    o3cmds=""
    if [ "${cur:0:2}" != "--" -a "${cur:0:1}" != "-" ]; then
       o3cmds="$($cmd shell-completion --list-commands)"
    fi

    selopts=""
    echo "$o3cmds" | tr ' ' '\n' | grep -v "version" | grep -qE "^$cur$"
    if [ $? -eq 0 ]; then
       # All commands except 'version' takes at least one option.
       # If the requested command is not "version", attach the '--' now
       COMPREPLY=( "$first --")
    elif [ $COMP_CWORD -eq 1 ]; then
        # The first argument is always an openvpn3 command
        # and it never starts with - or --
        COMPREPLY=( $( compgen -W "$o3cmds" $cur ) )
    elif [ $COMP_CWORD -gt 1 ]; then
        if [ "${cur:0:2}" == "--" -o "${cur:0:1}" == "-" ]; then
            # If the argument starts with '-' or '--' provide list of options
            comp_op="-W"
            selopts="$($cmd shell-completion --list-options $first)"
        else
            # Some options can get some extra help from bash
            case "${prev}" in
            "--config")  # Takes configuration profile names and file names
                # Prepare a simple filter, providing partial matching
                filter="cat" # by default everything passes
                if [ -n "$cur" ]; then
                    filter="grep -E ^$cur"
                fi
                comp_op="-W"
                if [ "config-import" = "${first}" -o "session-start" = "${first}" ]; then
                    # Only list files which most likely are OpenVPN configuration files
                    selopts="$(grep -sm1 -E '(client|remote |port |lport |rport |key |cert |ca )' ${cur}*.conf ${cur}*.ovpn | cut -d: -f1 | $filter | tr '\n' ' ')"

                    # Add directories too, but ignore those starting with '.{some-alpha-num-letters}'
                    selopts="$(compgen -d -- $cur | sed 's#$#/#' | grep -vE '^\.\w+' | tr '\n' ' ') $selopts"
                fi

                # In addition, extend with all pre-loaded configurations
                selopts="$($cmd shell-completion --list-options $first --arg-help $prev) $selopts"
                ;;

            "--grant"|"--revoke") # Takes username (or UID, which we don't tackle here)
                comp_op="-u"
                selopts=""
                ;;

            *)
                # Otherwise try to fill out with possible argument values for the
                # provided option
                comp_op="-W"
                arghelp="$prev"
                if [ "$cur" == "=" ]; then
                        arghelp="$prev$cur"
                fi
                if [ -n "$first" -a -z "${cur}" -a -z "${selopts}" ]; then
                   selopts="--"
                else
                   selopts="$($cmd shell-completion --list-options $first --arg-help $arghelp)"
                fi
                ;;
            esac
        fi
        if [ "$cur" == "=" ]; then
            cur=""
        fi
        COMPREPLY=( $( compgen ${comp_op} "${selopts}" -- $cur ) )
    fi
}

_openvpn3_completion()
{
    _openvpn3_generic_completion openvpn3
}
complete -F _openvpn3_completion -o nospace openvpn3


_openvpn3admin_completion()
{
    _openvpn3_generic_completion openvpn3-admin
}
complete -F _openvpn3admin_completion -o nospace openvpn3-admin