#! /bin/sh
# Start Open vSwitch guests
# 
# Written by Ewen McNeill <ewen@naos.co.nz>, 2014-10-06
# Updated by Ewen McNeill <ewen@naos.co.nz>, 2014-10-07
#---------------------------------------------------------------------------

set -e

PATH=/usr/bin:/bin
export PATH

BIN_DIR=$(dirname $0)
if [ -z "${BIN_DIR}" ]; then BIN_DIR="."; fi
case "${BIN_DIR}" in
  .)  BIN_DIR="$(pwd)";            ;;
  /*)                              ;; 
  *)  BIN_DIR="$(pwd)/${BIN_DIR}"; ;;
esac

NETSETUP="${NETSETUP:-${BIN_DIR}/dockerovs}"
OVS_SWITCH="${OVS_SWITCH:-kiwipycon}"
IP4_PREFIX="${IP4_PREFIX:-172.31.1}"
RYU_MANAGER="${RYU_MANAGER:-/usr/local/bin/ryu-manager}"
RYU_APP="${RYU_APP:-/home/ryu/kiwipycon3.py}"
GUEST_IMAGE="${GUEST_IMAGE:-kiwipycon-guest}"

ensure_guest_running() {
    NAME="$1"
    IP="$2"
    EXISTING_GUEST=$(docker ps -a | 
                     awk 'substr($0,139) ~ '"/${NAME}"'/ { print $1;}')
    if [ -n "${EXISTING_GUEST}" ]; then
      if docker ps | grep -q "^${EXISTING_GUEST}" >/dev/null; then
        #echo "Found container: ${EXISTING_GUEST}" >&2
        CONTAINER="${EXISTING_GUEST}"        # Already running
      else
        #echo "Restarting container ${NAME} (${EXISTING_GUEST})" >&2
        CONTAINER=$(docker start "${EXISTING_GUEST}")  # Restart container
      fi
    else
      CONTAINER=$(docker run -d -i -t --net=none --name="${NAME}" \
                  "${GUEST_IMAGE}" /bin/bash)
    fi
    sudo "${NETSETUP}" "${OVS_SWITCH}" "${CONTAINER}" "${IP}"
    echo "${CONTAINER}"
}

# Remove the Open vSwitch, so that we get a clean-start on port allocations
sudo ovs-vsctl --if-exists del-br "${OVS_SWITCH}"

# Start first guest, if not already running
GUEST_1=$(ensure_guest_running kiwipycon_h1 "${IP4_PREFIX}.1/24")

# Start second guest
GUEST_2=$(ensure_guest_running kiwipycon_h2 "${IP4_PREFIX}.2/24")

# Start the controller Ryu instance, auto-running ryu
CONTROLLER=$(docker run -d -i -t -p 6633:6633 -p 6653:6653 ryu-kiwipycon su -c "${RYU_MANAGER} ${RYU_APP}" ryu)
docker attach "${CONTROLLER}"