#!/bin/bash
#
# Copyright 2012 Hewlett-Packard Development Company, L.P.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

set -e

# Prevent perl from complaining a lot, but also remove any unexpected side-effects
# of $LANG varying between build hosts
export LANG=C

SCRIPTNAME=$(basename $0)
SCRIPT_HOME=$(dirname $0)
export _LIB=$(dirname $0)/../lib
source $_LIB/die

function show_options () {
    echo "Options:"
    echo "    -a i386|amd64 -- set the architecture of the image"
    echo "    -o filename -- set the name of the output file"
    echo "    -x -- turn on tracing"
    echo "    -u -- uncompressed; do not compress the image - larger but faster"
    echo "    -c -- clear environment before starting work"
    echo "    -n skip the default inclusion of the 'base' element"
    echo "    -p package[,package,package] -- list of packages to install in the image"
    echo
    echo "ELEMENTS_PATH will allow you to specify multiple locations for the elements."
    exit 0
}

INSTALL_PACKAGES=""
COMPRESS_IMAGE="true"
TEMP=`getopt -o a:ho:xucnp: -n $SCRIPTNAME -- "$@"`
if [ $? != 0 ] ; then echo "Terminating..." >&2 ; exit 1 ; fi

# Note the quotes around `$TEMP': they are essential!
eval set -- "$TEMP"

while true ; do
    case "$1" in
        -a) export ARCH=$2; shift 2 ;;
        -o) export IMAGE_NAME=$2; shift 2 ;;
        -h) show_options;;
        -x) shift; set -x;;
        -u) shift; export COMPRESS_IMAGE="";;
        -c) shift ; export CLEAR_ENV=1;;
        -n) shift; export SKIP_BASE="1";;
        -p) IFS="," read -a INSTALL_PACKAGES <<< "$2"; export INSTALL_PACKAGES ; shift 2 ;;
        --) shift ; break ;;
        *) echo "Internal error!" ; exit 1 ;;
    esac
done

if [ "$CLEAR_ENV" = "1" -a "$HOME" != "" ]; then
  echo "Re-execing to clear environment."
  echo "(note this will prevent much of the local_config element from working)"
  exec -c $0 "$@"
fi

for arg do IMAGE_ELEMENT="$IMAGE_ELEMENT $arg" ; done

if [ "$SKIP_BASE" != "1" ]; then
  IMAGE_ELEMENT="base $IMAGE_ELEMENT"
fi

source $_LIB/img-defaults
source $_LIB/common-functions
source $_LIB/img-functions

IMAGE_ELEMENT=$($SCRIPT_HOME/element-info --expand-dependencies $IMAGE_ELEMENT)

echo "Building elements: $IMAGE_ELEMENT"
echo "If prompted for sudo, install sudoers.d/img-build-sudoers into /etc/sudoers.d and restart the build."

# TODO: make into an element.
ensure_nbd

mk_build_dir
eval_run_d block-device-size "IMAGE_SIZE="

qemu-img create -f qcow2 -o preallocation=metadata $TMP_IMAGE_PATH ${IMAGE_SIZE}G

# Should have a grab-next-dev helper ?
NBD_DEV=/dev/nbd0
if [[ $(qemu-nbd --help | grep cache) == *writeback* ]] ; then
  CACHE="--cache=writeback"
else
  echo "Warning: qemu-nbd without --cache=writeback is /slow/."
  CACHE=""
fi
sudo qemu-nbd -c $NBD_DEV $CACHE $TMP_IMAGE_PATH
export EXTRA_UNMOUNT="sudo qemu-nbd -d $NBD_DEV"
export IMAGE_BLOCK_DEVICE=$NBD_DEV
eval_run_d block-device "IMAGE_BLOCK_DEVICE="

sudo mkfs -F -t $FS_TYPE -L cloudimg-rootfs ${IMAGE_BLOCK_DEVICE}

mount_tmp_image ${IMAGE_BLOCK_DEVICE}

create_base
run_d extra-data
# Run pre-install scripts. These do things that prepare the chroot for package installs
run_d_in_target pre-install
do_extra_package_install
# Call install scripts to pull in the software users want.
run_d_in_target install
prepare_first_boot
finalise_base
unmount_image
compress_image
save_image $IMAGE_NAME.$IMAGE_TYPE