#!/bin/bash
#
# Copyright (c) 2018 Intel Corporation
#
# SPDX-License-Identifier: Apache-2.0

set -e

die()
{
	local msg="$*"
	echo "ERROR: ${msg}" >&2
	exit 1
}

OK()
{
	local msg="$*"
	echo "[OK] ${msg}" >&2
}

info()
{
	local msg="$*"
	echo "INFO: ${msg}"
}

warning()
{
	local msg="$*"
	echo "WARNING: ${msg}"
}

check_program()
{
	type "$1" >/dev/null 2>&1
}

check_root()
{
	if [ "$(id -u)" != "0" ]; then
		echo "Root is needed"
		exit 1
	fi
}

generate_dnf_config()
{
	REPO_NAME=${REPO_NAME:-"base"}
	CACHE_DIR=${CACHE_DIR:-"/var/cache/dnf-${OS_NAME}"}
	cat > "${DNF_CONF}" << EOF
[main]
cachedir=${CACHE_DIR}
logfile=${LOG_FILE}
keepcache=0
debuglevel=2
exactarch=1
obsoletes=1
plugins=0
installonly_limit=3
reposdir=/root/mash
retries=5
EOF
	if [ "$BASE_URL" != "" ]; then
		cat >> "${DNF_CONF}" << EOF

[base]
name=${OS_NAME}-${OS_VERSION} ${REPO_NAME}
failovermethod=priority
baseurl=${BASE_URL}
enabled=1
EOF
	elif [ "$MIRROR_LIST" != "" ]; then
		cat >> "${DNF_CONF}" << EOF

[base]
name=${OS_NAME}-${OS_VERSION} ${REPO_NAME}
mirrorlist=${MIRROR_LIST}
enabled=1
EOF
	fi

	if [ -n "$GPG_KEY_URL" ]; then
		if [ ! -f "${CONFIG_DIR}/${GPG_KEY_FILE}" ]; then
			curl -L ${GPG_KEY_URL} -o ${CONFIG_DIR}/${GPG_KEY_FILE}
		fi
		cat >> "${DNF_CONF}" << EOF
gpgcheck=1
gpgkey=file://${CONFIG_DIR}/${GPG_KEY_FILE}
EOF
	fi

	if [ -n "$GPG_KEY_ARCH_URL" ]; then
		if [ ! -f "${CONFIG_DIR}/${GPG_KEY_ARCH_FILE}" ]; then
			 curl -L ${GPG_KEY_ARCH_URL} -o ${CONFIG_DIR}/${GPG_KEY_ARCH_FILE}
		fi
		cat >> "${DNF_CONF}" << EOF
       file://${CONFIG_DIR}/${GPG_KEY_ARCH_FILE}
EOF
	fi

}

build_rootfs()
{
	# Mandatory
	local ROOTFS_DIR="$1"

	[ -z "$ROOTFS_DIR" ] && die "need rootfs"

	# In case of support EXTRA packages, use it to allow
	# users add more packages to the base rootfs
	local EXTRA_PKGS=${EXTRA_PKGS:-""}

	#PATH where files this script is placed
	#Use it to refer to files in the same directory
	#Exmaple: ${CONFIG_DIR}/foo
	#local CONFIG_DIR=${CONFIG_DIR}

	check_root
	if [ ! -f "${DNF_CONF}" ]; then
		DNF_CONF="./kata-${OS_NAME}-dnf.conf"
		generate_dnf_config
	fi
	mkdir -p "${ROOTFS_DIR}"
	if [ -n "${PKG_MANAGER}" ]; then
		info "DNF path provided by user: ${PKG_MANAGER}"
	elif check_program "dnf"; then
		PKG_MANAGER="dnf"
	elif check_program "yum" ; then
		PKG_MANAGER="yum"
	else
		die "neither yum nor dnf is installed"
	fi

	DNF="${PKG_MANAGER} --config=$DNF_CONF -y --installroot=${ROOTFS_DIR} --noplugins"
	$DNF install ${EXTRA_PKGS} ${PACKAGES}

	[ -n "${ROOTFS_DIR}" ]  && rm -r "${ROOTFS_DIR}${CACHE_DIR}"
}

# Create a YAML metadata file inside the rootfs.
#
# This provides useful information about the rootfs than can be interrogated
# once the rootfs has been converted into a image/initrd.
create_summary_file()
{
	local -r rootfs_dir="$1"

	[ -z "$rootfs_dir" ] && die "need rootfs"

	local -r file_dir="/var/lib/osbuilder"
	local -r dir="${rootfs_dir}${file_dir}"

	local -r filename="osbuilder.yaml"
	local file="${dir}/${filename}"

	local -r now=$(date '+%Y-%m-%dT%T.%N%zZ')

	# sanitise package lists
	PACKAGES=$(echo "$PACKAGES"|tr ' ' '\n'|sort -u|tr '\n' ' ')
	EXTRA_PKGS=$(echo "$EXTRA_PKGS"|tr ' ' '\n'|sort -u|tr '\n' ' ')

	local -r packages=$(for pkg in ${PACKAGES}; do echo "      - \"${pkg}\""; done)
	local -r extra=$(for pkg in ${EXTRA_PKGS}; do echo "      - \"${pkg}\""; done)

	mkdir -p "$dir"

	# Semantic version of the summary file format.
	#
	# XXX: Increment every time the format of the summary file changes!
	local -r format_version="0.0.2"

	local -r osbuilder_url="https://github.com/kata-containers/osbuilder"

	local agent="${AGENT_DEST}"
	[ "$AGENT_INIT" = yes ] && agent="${init}"

	local -r agent_version=$("$agent" --version|awk '{print $NF}')

	cat >"$file"<<-EOT
	---
	osbuilder:
	  url: "${osbuilder_url}"
	  version: "${OSBUILDER_VERSION}"
	rootfs-creation-time: "${now}"
	description: "osbuilder rootfs"
	file-format-version: "${format_version}"
	architecture: "${ARCH}"
	base-distro:
	  name: "${OS_NAME}"
	  version: "${OS_VERSION}"
	  packages:
	    default:
${packages}
	    extra:
${extra}
	agent:
	  url: "https://${GO_AGENT_PKG}"
	  name: "${AGENT_BIN}"
	  version: "${agent_version}"
	  agent-is-init-daemon: "${AGENT_INIT}"
EOT

	local rootfs_file="${file_dir}/$(basename "${file}")"
	info "Created summary file '${rootfs_file}' inside rootfs"
}