#!/bin/bash

CHARM="nova-cloud-controller"
CONF_DIR="/etc/nova"

NOVA_CONF="/etc/nova/nova.conf"
API_CONF="/etc/nova/api-paste.ini"
QUANTUM_CONF="/etc/quantum/quantum.conf"
QUANTUM_API_CONF="/etc/quantum/api-paste.ini"

NET_MANAGER=$(config-get network-manager)

if [[ -e $CHARM_DIR/lib/nova/nova-common ]] ; then
  . $CHARM_DIR/lib/nova/nova-common
else
  juju-log "Couldn't load $CHARM_DIR/lib/nova/nova-common" && exit 1
fi

function determine_services {
  # Sets the global $SERVICES which contains a list of all services
  # managed by the charm.  This changes based on OpenStack release.
  # Currently, the services also determines what ends up in $PACKAGES.

  # base c-c services supported across all os releases since essex.
  SERVICES="nova-api-ec2 nova-api-os-compute nova-objectstore nova-cert nova-scheduler"

  # determine additional services, dependent on what version of OS.
  local install_src="$(config-get openstack-origin)"
  install_src=$(get_os_codename_install_source "$install_src")
  local os_vers=$(get_os_codename_package "nova-common")
  if [[ "$os_vers" == "none" ]] ; then
    [[ "$install_src" == "unknown" ]] && echo "$SERVICES" && return 0
  fi

  os_vers="$install_src"
  if [[ "$os_vers" != "essex" ]] && [[ "$os_vers" != "folsom" ]] ; then
    # nova-conductor was introduced in grizzly.
    SERVICES="$SERVICES nova-conductor"
  else
      local n_vol=$(relation-ids nova-volume-service)
      if [[ -n "$n_vol" ]] ; then
        # nova-volume was dropped in G but may still be deployed for E + F,
        # but should only be managed when a relation to nova-volume exists.
        SERVICES="$SERVICES nova-api-os-volume"
        # need to also ensure the package gets installed here.  if the relation
        # is introduced during another hook, a call to 'service_ctl all' will
        # require it to be there.
        dpkg -l | grep -q nova-api-os-volume ||
          apt-get -y install nova-api-os-volume
      fi
  fi

  # quantum is really only supported for folsom and beyond.
  if [[ "$NET_MANAGER" == "Quantum" ]] ; then
    [[ "$os_vers" == "essex" ]] &&
      error_out "Quantum network manager only supported for Folsom + beyond."
    SERVICES="$SERVICES quantum-server"
  fi
}

function determine_packages {
  # Derive a list of packages based on what our service needs are.  This changes
  # depending on several factors.
  determine_services
  PACKAGES="$SERVICES python-mysqldb python-keystone uuid charm-helper-sh"

  if echo $PACKAGES | grep -q "quantum-server" ; then
    case "$(config-get quantum-plugin)" in
      "ovs") PACKAGES="$PACKAGES quantum-plugin-openvswitch" ;;
      "nvp") PACKAGES="$PACKAGES quantum-plugin-nicira" ;;
    esac
  fi
  juju-log "$CHARM: Determined required packages: $PACKAGES."
}

function determine_quantum_config {
  # Set QUANTUM_PLUGIN and point QUANTUM_CORE_PLUGIN and QUANTUM_PLUGIN_CONF
  # to the correct files based on configuration.
  QUANTUM_PLUGIN=${QUANTUM_PLUGIN:-$(config-get quantum-plugin)}
  case "$QUANTUM_PLUGIN" in
    "ovs")
      QUANTUM_CORE_PLUGIN="quantum.plugins.openvswitch.ovs_quantum_plugin.OVSQuantumPluginV2"
      QUANTUM_PLUGIN_CONF="/etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini"
      ;;
    "nvp")
      QUANTUM_CORE_PLUGIN="quantum.plugins.nicira.nicira_nvp_plugin.QuantumPlugin.NvpPluginV2"
      QUANTUM_PLUGIN_CONF="/etc/quantum/plugins/nicira/nvp.ini"
      ;;
  *)
    juju-log "Unrecognised plugin for quantum: $QUANTUM_PLUGIN" && exit 1
    ;;
  esac
}

function configure_quantum_networking {
  determine_quantum_config
  if [ "$(config-get conf-ext-net)" != "no" ] &&
     [ "$QUANTUM_PLUGIN" == "ovs" ] &&
     [ -f /etc/quantum/novarc ] &&
     [ -n "$(relation-ids shared-db)" ]; then
    juju-log "Configuring external networking for quantum"
    # Use helper to create external network gateway
    # and router using generated credentials
    . /etc/quantum/novarc
    quantum-ext-net -g $(config-get ext-net-gateway) \
                    -c $(config-get ext-net-cidr) \
                    -f $(config-get pool-floating-start):$(config-get pool-floating-end) \
                    $(config-get ext-net-name)
  fi
}

function ssh_authorized_keys {
  local key="$1"
  local action="$2"
  local exists=""

  local sunit=$(echo $JUJU_REMOTE_UNIT | cut -d/ -f1)
  mkdir -p /etc/nova/compute_ssh/$sunit
  local authorized_keys="/etc/nova/compute_ssh/$sunit/authorized_keys"

  [[ -e "$authorized_keys" ]] &&
    grep -q "^$key" $authorized_keys && exists="true"

  if [[ "$action" == "add" ]] ; then
    [[ -n "$exists" ]] &&
      juju-log "$CHARM: SSH key already authorized for $JUJU_REMOTE_UNIT." &&
        return 0

    echo "$key" >>$authorized_keys
    juju-log "$CHARM: Authorized new SSH key for $JUJU_REMOTE_UNIT."
    return 0
  elif [[ "$action" == "remove" ]] ; then
    # we have no way of getting to the relation state during a departed hook.
    # we only have the peer's unit name, so remove an authorized key based on
    # its comment, which should can be derived from the remote unit name and
    # gets passed in here from caller as key/$1
    local key_ln=$(sed -n "\, ${key}$,=" $authorized_keys)
    [[ -z "$key_ln" ]] &&
      juju-log "$CHARM: Cannot remove SSH key for $key, not authorized?" &&
        return 0

    for ln in $key_ln ; do
      sed -i "${ln}d" $authorized_keys
      juju-log "$CHARM: Removed existing SSH key ($key) from authorized_keys."
    done
    return 0
  else
    error_out "$CHARM: ssh_authorize_keys() invalid action specified: $action."
  fi
}

function ssh_known_hosts {
  # Keeps the system-wide SSH known hosts file up to date with compute
  # nodes host keys.
  local host="$1"
  local sunit=$(echo $JUJU_REMOTE_UNIT | cut -d/ -f1)
  mkdir -p /etc/nova/compute_ssh/$sunit
  local known_hosts="/etc/nova/compute_ssh/$sunit/known_hosts"
  juju-log "$CHARM: Ensuring host is included and up to date in $known_hosts."

  [[ ! -e $known_hosts ]] && touch $known_hosts

  local remote_key=""
  remote_key=$(ssh-keyscan -H -t rsa $host) ||
    error_out "$CHARM: Couldn't obtain SSH host key from $host."
  local existing=$(ssh-keygen -f $known_hosts -H -F $host | tail -n1)
  if [[ -n "$existing" ]] ; then
    juju-log "$CHARM: Found existing SSH known host key for $host."
    [[ "$existing" == "$remote_key" ]] && echo "HI"
    remote=$(echo $remote_key | awk '{ print $2" "$3 }')
    existing=$(echo $existing | awk '{ print $2" "$3 }')
    if [[ "$remote" == "$existing" ]] ; then
      juju-log "$CHARM: SSH known host key for $host is up to date."
      return 0
    fi
    juju-log "$CHARM: Removing outdated SSH host key for $host."
    ssh-keygen -f $known_hosts -R $host
  else
    juju-log "$CHARM: No known hosts entry for $host."
  fi
  juju-log "$CHARM: Adding new SSH known hosts entry for $host."
  echo $remote_key >>$known_hosts

}

function ssh_compute {
  if [[ "$1" == "add" ]] ; then
    local ssh_key=$(relation-get ssh_public_key)
    [[ -z "$ssh_key" ]] &&
      juju-log "$CHARM: ssh_compute peer not ready." && exit 0

    ssh_authorized_keys "$ssh_key" "add"

    # need to ensure known hosts entries for all possible addresses
    . /usr/share/charm-helper/sh/net.sh
    local known_hosts=""
    local private_address=$(relation-get private-address)
    known_hosts="$private_address"
    if ! ch_is_ip "$private_address" ; then
      known_hosts="$known_hosts $(get_ip $private_address)"
      known_hosts="$known_hosts $(echo $private_address | cut -d. -f1)"
    fi
    for host in $known_hosts ; do
      ssh_known_hosts "$host"
    done
  elif [[ "$1" == "remove" ]] ; then
    # remove key by referencing remote unit, not entire key.
    local remote_unit=$(echo $JUJU_REMOTE_UNIT | sed -e 's,/,-,g')
    ssh_authorized_keys "$remote_unit" remove
  else
    error_out "ssh_compute: Invalid parameter: $1."
  fi

  local sunit=$(echo $JUJU_REMOTE_UNIT | cut -d/ -f1)

  # base64 encodings should trigger new relation events as needed.
  relation-set \
    known_hosts="$(base64 /etc/nova/compute_ssh/$sunit/known_hosts)" \
    authorized_keys="$(base64 /etc/nova/compute_ssh/$sunit/authorized_keys)"
}