#! /bin/bash
#
# This collection of scripts aims to install a NOVIT cluster easily, with help of QEMU
#
#
#


## QEMU functions
#
prereqs_qemu() {
  for com in qemu-system-x86_64 truncate docker iptables ; do
    command -v $com 1>/dev/null || error Command $com not found, please install it. Aborting...
  done
}
setup_network_qemu() {
  if ! ip li show $QEMU_BR_NAME &>/dev/null ; then
    ip li add name $QEMU_BR_NAME type bridge
    ip li set $QEMU_BR_NAME up
  fi
  QEMU_BR_IP=$(extract_var clusters gateway)
  QEMU_BR_MASK=$(extract_var clusters netmask)
  if [ $(echo $QEMU_BR_IP | wc -w) -gt 1 ]; then
    perror "More than one cluster is configured, not compatible with our quick-start setup, exiting"
  fi
  pinfo "Using detected gateway IP $QEMU_BR_IP for bridge $QEMU_BR_NAME"
  if ! ip a show dev $QEMU_BR_NAME | grep $QEMU_BR_IP ; then
    ip a add $QEMU_BR_IP/$QEMU_BR_MASK dev $QEMU_BR_NAME
    iptables -t nat -I POSTROUTING -j MASQUERADE -s $QEMU_BR_IP/$QEMU_BR_MASK \! -o $QEMU_BR_NAME
    iptables -I FORWARD -o $QEMU_BR_NAME -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
    iptables -I FORWARD -j ACCEPT -i $QEMU_BR_NAME
  fi
  if ! test -d /etc/qemu; then
    mkdir -p /etc/qemu
  fi
  if ! grep -qs "allow $QEMU_BR_NAME" /etc/qemu/bridge.conf; then
    echo "allow $QEMU_BR_NAME" >> /etc/qemu/bridge.conf
  fi
}

run_qemu() {
  id=1
  for host in ${!hosts[*]}; do
    ip route show |grep "${hosts[$host]} dev $QEMU_BR_NAME" ||\
        ip route add ${hosts[$host]} dev $QEMU_BR_NAME
    pinfo "Starting host $host with ip ${hosts[$host]}"
    qemu-system-x86_64 -enable-kvm -smp $QEMU_VM_CPU -m $QEMU_VM_MEM \
      -nic bridge,br=$QEMU_BR_NAME,mac=42:42:42:42:42:0${id} \
      -kernel $ctxdir/data/$host/kernel -initrd $ctxdir/data/$host/initrd -vga qxl \
      -drive format=raw,file=$ctxdir/data/$host/disk &
    echo $! >$ctxdir/data/$host/pid
    ((++id))
  done
  pinfo "$(ls $ctxdir/data/*/pid|wc -w) host(s) have been started"
}
# # # # # # # #



source $(dirname $0)/.common
check_root
prereqs
check_conf
#fresh_start
trap clean SIGINT SIGTERM SIGKILL
declare -A hosts
setup_network_qemu
get_hosts
get_parts
destroyvms
run_qemu