#/bin/bash

#
# little class about bash extension parametters.
#
# ${myvar#pattern} delete shortest occurence from the begining
# ${myvar##pattern} delete longuest occurence from begining
# ${myvar%pattern} delete shortest occurence from the end
# ${myvar%%pattern} delete longuest occurence from the end
#
# conclusion, use of # will delete the pattern at begining
# and % will delete the parameter at the end.


default_user="root"
default_hostname="localhost"
default_ssh_port="22"
default_rsp_port="3389"
default_vnc_port="5900"

Version="2.0.0"

Help_message="
$(basename $0) PROTOCOL [OPTION] [OPTION=VALUE]

script which permit to launch a remote connection protocol.

PROTOCOL available
    ssh                 A command line protocol which can be used to connect with tcp
    rsp                 The windows remote server protocol

PROTOCOL #TODO
    vnc                 Virtual Networking Computing, permit to have access to a graphical user interface.

OPTION available
    -v, --version               print the version and exit
    -h, --help                  print this help and exit
    -u <user>,--user=<user>     Select the user, by default root
    -p <port>,--port=<port>     Select the port, by default 10022
    -H <hostname>, --hostname=<hostname>    Select the host to connect #TODO
"


start_ssh() {
    if [ "${port}" == "" ]
    then
        port="${default_ssh_port}"
    fi
    echo "start ssh"
}

start_rsp() {
    if [ "${port}" == "" ]
    then
        port="${default_rsp_port}"
    fi
    echo "start rsp"
}


case "$1" in
    "ssh")
        protocol="ssh"
        ;;
    "rsp")
        protocol="rsp"
        ;;
    *)
        echo "protocol $1 uknown" >&2
        exit 1
esac

# looking for double parametters.

for (( arg=2; arg<$#; arg++)); do
    value="$((arg+1))"
    if [ "${!arg}" == "-u" ]
    then
        user="${!value}"
    elif [ "${!arg}" == "-p" ]
    then
        port="${!value}"
    elif [ "${!arg}" == "-H" ]
    then
        hostname="${!arg}"
    fi
done


# looking for all parametter alone

for i in "$@"; do
    if [ "${i%=*}" == "--user" ]
    then
        user="${i#*=}"
    elif [ "${i%=*}" == "--port" ]
    then
        port="${i#*=}"
    elif [ "${i#*=}" == "--hostname" ]
    then
        hostname="${i#*=}"
    elif [ "${i}" == "--version" ] || [ "${i}" == "-v" ]
    then
        echo "$(basename $0) v.${Version}"
        exit 0
    elif [ "${i}" == "--help" ] || [ "${i}" == "-h" ]
    then
        echo "$Help_message"
        exit 0
    fi
done

if [ "${user}" == "" ]
then
    user="${default_user}"
fi
if [ "${hostname}" == "" ]
then
    hostname="${default_hostname}"
fi



case "${protocol}" in
    "ssh")
        start_ssh
        ;;
    "rsp")
        start_rsp
        ;;
    *)
        echo "CRITICAL protocol ${protocol} uknown" >&2
        exit 1
        ;;
esac


echo try to connect with user=${user} and port=${port}
echo port=${port}

ssh -o "StrictHostKeyChecking no" -o "UserKnownHostsFile=/dev/null" -p ${port} ${user}@localhost


# add possibility for vnc and rsp
# rsp command to connect: xfreerdp /v:hostname /u:user /dynamic-resolution