#!/bin/bash
#
# lxc-create wrapper by Roberto Puzzanghera https://www.sagredo.eu
#
# Usage: my_lxc-create -h
#

# Default variables. You can overwrite them passing options to the command
MIRROR=https://mirrors.slackware.com/slackware
GW=10.0.0.1                  # gateway
SLACKPKG_TEMPLATE=current    # slackpkg template (pkg list). Alternative: my_minimal
LXC_TEMPLATE=my_template     # lxc template. Use "slackware" to load /usr/share/lxc/templates/lxc-slackware
                             #               Use "download" to download an image (net config and other options ignored in that case)
RELEASE=current              # Release
DHCP=no	                     # Put yes if you want DHCP

############################################################################# do not touch below this line

. my_lxc-common

function usage() {
  echo "Usage: $0 script takes the following options:
  -n  <name>              Set container name to use. **Required**
  -r  <release>           Set Slackware release to use. Default: 15.0
  -s  <slackpkg-template> slackpkg template (pkg list). Default: \"15.0\". Alternative: \"my_minimal\"
  -t  <lxc-template>      Set lxc template to use. Default: \"my_template\".
                          Use \"slackware\" to load /usr/share/lxc/templates/lxc-slackware
                          Use \"download\" to load /usr/share/lxc/templates/lxc-download (no net configuration will be done in this case)
  -m  <mirror>            Set mirror to use. If not set the one specified in the lxc template will be used
  -o  <domain>            Domain
  -d                      Use DHCP. Ignored if -i <ip> is passed
  -i  <ip>                IP address of the container
  -g  <gw>                Gateway
  -u  <user>              Set the system user that will own the container. If not declared the container will be privileged
  -h                      Print help options and exit"
}

# Define the flags the user can pass to the script
while getopts :n:r:s:t:m:o:di:g:u:h option
do
  case "${option}" in
  n) NAME=${OPTARG};;
  r) RELEASE=${OPTARG};;
  s) SLACKPKG_TEMPLATE=${OPTARG};;
  t) LXC_TEMPLATE=${OPTARG};;
  m) MIRROR=${OPTARG};;
  o) DOMAIN=${OPTARG};;
  d) DHCP=yes;;
  i) IP=${OPTARG};;
  g) GW=${OPTARG};;
  u) OWNER=${OPTARG};;
  h) usage;;
  :) echo
     echo "Please provide all required options."
     echo
     usage;;
  *) usage;;
esac
done

################################################################################ sanity check

# Container name must be provided
if [ -z "$NAME" ]; then
  echo
  echo "Container name is required (-n <name>)"
  echo
  usage
  exit 1
fi

# Exit if container already exist
container_exists $NAME
if [ $? -ne 0 ]; then
  echo "Container $NAME already exists. Exiting..."
  exit 0
fi

# LXC template check
if [ ! -x "/usr/share/lxc/templates/lxc-${LXC_TEMPLATE}" ]; then
  echo
  echo "LXC template /usr/share/lxc/templates/lxc-$LXC_TEMPLATE not found (-t template_name)"
  echo
  usage
  exit 1
fi

# slackpkg template check
if [ ! -e "/etc/slackpkg/templates/${SLACKPKG_TEMPLATE}.template" ]; then
  if [ "${LXC_TEMPLATE}" != "download" ] && [ "${LXC_TEMPLATE}" != "busybox" ] && [ "${LXC_TEMPLATE}" != "local" ] && [ "${LXC_TEMPLATE}" != "oci" ]; then
    echo
    echo "slackpkg template /etc/slackpkg/templates/${SLACKPKG_TEMPLATE}.template does not exist (-s template_name)"
    echo
    usage
    exit 1
  fi
fi

################################################################################

create_container() {
  release=$RELEASE \
  MIRROR=$MIRROR \
  TEMPLATE=$SLACKPKG_TEMPLATE \
  DOMAIN=$DOMAIN \
  lxc-create \
  -n $NAME \
  -t $LXC_TEMPLATE \
  --lxcpath=$LXC_PATH
}

# create the container
create_container
if [ $? -ne 0 ]; then
  echo "Failed in creating the container $NAME. Exiting..."
  exit 1
fi

# do not setup the net if it's not a slackware template
if [ "${LXC_TEMPLATE}" != "download" ] && [ "${LXC_TEMPLATE}" != "busybox" ] && [ "${LXC_TEMPLATE}" != "local" ] && [ "${LXC_TEMPLATE}" != "oci" ]; then
  # setup the net
  if [ -n "$IP" ]; then
    sed -i "s/IPADDRS\[0\]=\"\"/IPADDRS\[0\]=\"${IP}\/24\"/g" $LXC_PATH/$NAME/rootfs/etc/rc.d/rc.inet1.conf
  elif [ "$DHCP" = "yes" ]; then
    sed -i "s/USE_DHCP\[0\]=\"\"/USE_DHCP\[0\]=\"yes\"/g" $LXC_PATH/$NAME/rootfs/etc/rc.d/rc.inet1.conf
    sed -i "s/DHCP_HOSTNAME\[0\]=\"\"/DHCP_HOSTNAME\[0\]=\"${NAME}\.${DOMAIN}\"/g" $LXC_PATH/$NAME/rootfs/etc/rc.d/rc.inet1.conf
  fi
  sed -i "s/GATEWAY=\"\"/GATEWAY=\"${GW}\"/g" $LXC_PATH/$NAME/rootfs/etc/rc.d/rc.inet1.conf

  # Update CA certificates, followed by some bash in case we do not have perl:
  chroot $LXC_PATH/$NAME/rootfs /usr/sbin/update-ca-certificates -f 2>/dev/null
  cd $LXC_PATH/$NAME/rootfs/etc/ssl/certs
  for file in *.pem; do
    ln -sf "$file" "$(openssl x509 -hash -noout -in "$file")".0
  done
  cd - 1>/dev/null
# setup the net in systemd downloaded OS where a file /etc/systemd/network/eth0.network exists
elif [ "${LXC_TEMPLATE}" = "download" ] && [ -n "$IP" ] && [ -r $LXC_PATH/$NAME/rootfs/etc/systemd/network/eth0.network ]; then
  # grab the dns from host's resolv.conf
  DNS=$(sed -n "/#/! s/^nameserver \(.*\)/\1/p" /etc/resolv.conf | head -1)
  cat > $LXC_PATH/$NAME/rootfs/etc/systemd/network/eth0.network << __EOF__
[Match]
Name=eth0

[Network]
DHCP=false
Address=${IP}/24
Gateway=${GW}
DNS=${DNS}

[DHCPv4]
UseDomains=true

[DHCP]
ClientIdentifier=mac
__EOF__
  chmod +x $LXC_PATH/$NAME/rootfs/etc/systemd/network/eth0.network

  # append shared config file
  cat >> $LXC_PATH/$NAME/config << EOF

lxc.include = /etc/lxc/lxc-common.conf
EOF
fi

if [ -n "$OWNER" ]; then
  # If -u OWNER was passed then go for turning into unprivileged. $OWNER is the user who owns the container
  my_lxc-turn_into_unprivileged $NAME $OWNER
fi

exit 0