#!/bin/bash
# Copyright 1999-2014 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

# First let's get our own namespaces to avoid leaking crap.
if [[ -z ${UNSHARE} ]] ; then
  if type -P unshare >&/dev/null ; then
    uargs=()
    # Probe the namespaces as some can be disabled (or we are not root).
    unshare -m -- true >&/dev/null && uargs+=( -m )
    unshare -u -- true >&/dev/null && uargs+=( -u )
    unshare -i -- true >&/dev/null && uargs+=( -i )
    unshare -p -- true >&/dev/null && uargs+=( -p -f --mount-proc )
    # Re-exec ourselves in the new namespace.
    UNSHARE=true exec unshare "${uargs[@]}" -- "$0" "$@"
  fi
fi
unset UNSHARE

CATALYST_CONFIG=/etc/catalyst/catalyst.conf

# Probe the default source dir from this script name.
REPO_DIR=$(dirname "$(dirname "$(realpath "$0")")")

# Set up defaults that config files can override if they want.
SUBARCH=$(uname -m)
EMAIL_TO="releng@gentoo.org,gentoo-releng-autobuilds@lists.gentoo.org"
# Use full hostname by default as Gentoo servers will reject short names.
EMAIL_FROM="catalyst@$(hostname -f)"
EMAIL_SUBJECT_PREPEND="[${SUBARCH}-auto]"

# Variables updated by command line arguments.
declare -a config_files
config_files=()
verbose=0
keep_tmpdir=0
testing=0
preclean=0
lastrun=0
lock_file=

usage() {
  local msg=$1

  if [ -n "${msg}" ]; then
    printf "%b\n\n" "${msg}"
  fi

  cat <<EOH
Usage:
  catalyst-auto [-c|--config <config>] [-v|--verbose] [-h|--help]

Options:
  -c|--config         Specifies the config file to use (required)
  -C|--preclean       Clean up loose artifacts from previous runs
  -v|--verbose        Send output of commands to console as well as log
  -k|--keep-tmpdir    Don't remove temp dir when build finishes
  -t|--test           Stop after mangling specs and copying files
  --interval <days>   Exit if last successful run was less than <days> ago
  -l|--lock <file>    File to grab a lock on to prevent multiple invocations
  -h|--help           Show this message and quit

EOH
}

send_email() {
  local subject="${EMAIL_SUBJECT_PREPEND} $1"
  local message=$2
  local logfile=$3
  local body

  if [ -n "${logfile}" ]; then
    body=$(printf '%b\n\n\n' "${message}"; tail -n 200 "${logfile}"; printf '\n\n\nFull build log at %s\n' "${logfile}")
  else
    body=${message}
  fi

  printf 'From: %s\r\nTo: %s\r\nSubject: %s\r\n\r\n%b' \
    "${EMAIL_FROM}" "${EMAIL_TO}" "${subject}" "${body}" | \
    /usr/sbin/sendmail -f "${EMAIL_FROM}" ${EMAIL_TO//,/ }
}

# Usage: run_cmd <logfile> <command to run>
run_cmd() {
  local logfile="$1"
  shift

  if [ $verbose = 2 ]; then
    echo "*** Running command: $*"
    "$@" 2>&1 | tee -a "${logfile}"
  elif [ $verbose = 1 ]; then
    echo "*** Running command: $*"
    "$@" &>> "${logfile}"
  else
    "$@" &>> "${logfile}"
  fi

  # If we used tee above, make sure we pass back up the command's error.
  return ${PIPESTATUS[0]}
}

update_symlinks() {
  # This is a skeleton function that you can override from the config file.
  # It will be called by pre_build and after completing the build of a set
  # to ensure the symlinks point to the latest built stages.
  :
}

pre_build() {
  # This is a skeleton function that you can override from the config file.
  # It will be executed before the build is started. You can use this to
  # update the checkout of the releng repo
  :
}

post_build() {
  # This is a skeleton function that you can override from the config file.
  # It will be executed after the build is successfully completed. You can
  # use this to rsync the builds to another box
  :
}

catalyst_var() {
  # Extract a setting from the catalyst.conf.
  local var=$1
  (. "${CATALYST_CONFIG}"; echo "${!var}")
}

trigger_post_build() {
  if ! run_cmd "${TMPDIR}/log/post_build.log" post_build; then
    send_email "Catalyst build error - post_build" "The post_build function failed" "${TMPDIR}/log/post_build.log"
    exit 1
  fi
}

parse_args() {
	local a
	while [[ $# -gt 0 ]] ; do
		a=$1
		shift
		case "${a}" in
		-h|--help)
			usage
			exit 0
			;;
		-c|--config)
			config_files+=("$1")
			shift
			;;
		-v|--verbose)
			verbose=$(($verbose+1))
			;;
		-k|--keep-tmpdir)
			keep_tmpdir=1
			;;
		-t|--test)
			testing=1
			;;
		-C|--preclean)
			preclean=1
			;;
		--interval)
			lastrun=$1
			shift
			;;
		-l|--lock)
			lock_file=$1
			shift
			;;
		-*)
			usage "ERROR: You have specified an invalid option: ${a}"
			exit 1
			;;
		*)
			usage "ERROR: This script takes no arguments: ${a}"
			exit 1
			;;
		esac
	done
}

run_catalyst_commands() {
	doneconfig=0
	for config_file in "${config_files[@]}"; do
		# Make sure all required values were specified.
		if [[ -z "${config_file}" || ! -e "${config_file}" ]]; then
			usage "ERROR: You must specify a valid config file to use: '$config_file' is not valid"
			exit 1
		fi
		source "${config_file}"
		doneconfig=1
	done
	if [[ ${doneconfig} == 0 ]]; then
		usage "ERROR: You must specify at least one valid config file to use"
		exit 1
	fi

	# Some configs will set this explicitly, so don't clobber it.
	: ${BUILD_SRCDIR_BASE:=$(catalyst_var storedir)}

	# See if we had a recent success.
	if [[ ${lastrun} != 0 ]]; then
		last_success_file="${BUILD_SRCDIR_BASE}/.last_success"
		delay=$(( lastrun * 24 * 60 * 60 ))
		last_success=$(head -1 "${last_success_file}" 2>/dev/null || echo 0)
		if [[ $(date +%s) -lt $(( last_success + delay )) ]]; then
			exit 0
		fi
	fi

	DATESTAMP=$(date -u +%Y%m%d)
	TIMESTAMP=$(date -u +%Y%m%dT%H%M%SZ)
	TMPDIR=$(mktemp -d --tmpdir="${TMP_PATH:-/tmp}" "catalyst-auto.${TIMESTAMP}.XXXXXX")

	# Nuke any previous tmpdirs to keep them from accumulating.
	if [[ ${preclean} == 1 ]]; then
		rm -rf "${TMPDIR%.??????}".*
		mkdir "${TMPDIR}"
	fi

	if [[ ${verbose} -ge 1 ]]; then
		echo "TMPDIR = ${TMPDIR}"
		echo "DATESTAMP = ${DATESTAMP}"
		echo "TIMESTAMP = ${TIMESTAMP}"
	fi

	if ! mkdir -p "${TMPDIR}"/{specs,kconfig,log}; then
		echo "Couldn't create tempdirs!"
		exit 1
	fi

	if ! run_cmd "${TMPDIR}/log/pre_build.log" pre_build; then
		send_email "Catalyst build error - pre_build" "The pre_build function failed" "${TMPDIR}/log/pre_build.log"
		exit 1
	fi

	cd "${SPECS_DIR}" || exit 1

	for a in "" ${SETS}; do
		if [[ -z "${a}" ]]; then
			specs_var="SPECS"
			optional_specs_var="OPTIONAL_SPECS"
		else
			specs_var="SET_${a}_SPECS"
			optional_specs_var="SET_${a}_OPTIONAL_SPECS"
		fi

		for i in ${!specs_var} ${!optional_specs_var}; do
			cp --parents "${i}" "${TMPDIR}"/specs/
		done
	done

	find "${KCONFIG_DIR}" -type f -exec cp {} "${TMPDIR}"/kconfig \;

	cd "${TMPDIR}/specs" || exit 1

	# Fix up specs with datestamp
	for i in $(find -name '*.spec'); do
		# Grab current version_stamp and source_subpath
		old_version_stamp=$(grep version_stamp "${i}" | sed -e 's|^version_stamp: *||')
		old_source_subpath=$(grep source_subpath "${i}" | sed -e 's|^source_subpath: *||')

		new_version_stamp=$(echo "${old_version_stamp}" | sed -e "s|^\(.*-\)\?.*$|\1${TIMESTAMP}|")
		new_source_subpath=$(echo "${old_source_subpath}" | sed -e "s|${old_version_stamp}|${new_version_stamp}|")

		sed -i "s|^version_stamp:.*$|version_stamp: ${new_version_stamp}|" "${i}"
		sed -i "s|^snapshot:.*$|snapshot: ${TIMESTAMP}|" "${i}"

		# We don't want to mangle the source_subpath for our stage1 spec
		if ! grep -q '^target: *stage[14]$' "${i}"; then
			sed -i "s|^source_subpath:.*$|source_subpath: ${new_source_subpath}|" "${i}"
		fi

		sed -i "/^livecd\/iso/s|${old_version_stamp}|${new_version_stamp}|" "${i}"
		sed -i "/^livecd\/volid/s|${old_version_stamp}|${new_version_stamp}|" "${i}"

		kconfig_lines=$(grep '^boot/kernel/[^/]\+/config:' "${i}")
		if [[ -n ${kconfig_lines} ]]; then
			echo "${kconfig_lines}" | while read line; do
				key=$(echo "${line}" | cut -d: -f1)
				filename=$(basename $(echo "${line}" | cut -d: -f2))
				sed -i "s|^${key}:.*\$|${key}: ${TMPDIR}/kconfig/${filename}|" "${i}"
			done
		fi

		# Expand vars that the spec expects us to.
		sed -i \
			-e "s:@DATESTAMP@:${DATESTAMP}:g" \
			-e "s:@TIMESTAMP@:${TIMESTAMP}:g" \
			-e "s:@REPO_DIR@:${REPO_DIR}:g" \
			"${i}"
	done

	if [[ ${testing} == 1 ]]; then
		echo "Exiting due to --test"
		exit
	fi

	if [[ ${preclean} == 1 ]]; then
		snapshot_cache=$(catalyst_var snapshot_cache)
		if [[ -z ${snapshot_cache} ]]; then
			echo "error: snapshot_cache not set in config file"
			exit 1
		fi
		pushd "${BUILD_SRCDIR_BASE}" >/dev/null || exit 1
		rm -rf --one-file-system \
			kerncache packages snapshots tmp "${snapshot_cache}"/*
		popd >/dev/null
	fi

	# Create snapshot
	if ! run_cmd "${TMPDIR}/log/snapshot.log" catalyst -c "${CATALYST_CONFIG}" -s "${TIMESTAMP}"; then
		send_email "Catalyst build error - snapshot" "" "${TMPDIR}/log/snapshot.log"
		exit 1
	fi

	build_failure=0

	timeprefix=()
	which time >/dev/null && timeprefix=( "time" )

	for a in "" ${SETS}; do
		if [[ -z ${a} ]]; then
			specs_var="SPECS"
			optional_specs_var="OPTIONAL_SPECS"
		else
			specs_var="SET_${a}_SPECS"
			optional_specs_var="SET_${a}_OPTIONAL_SPECS"
		fi

		for i in ${!specs_var}; do
			LOGFILE="${TMPDIR}/log/$(echo "${i}" | sed -e 's:/:_:' -e 's:\.spec$::').log"
			run_cmd "${LOGFILE}" "${timeprefix[@]}" catalyst -a -c "${CATALYST_CONFIG}" -f "${i}"
			if [[ $? != 0 ]]; then
				build_failure=1
				send_email "Catalyst fatal build error - ${i}" "" "${LOGFILE}"
				continue 2
			else
				trigger_post_build
			fi
		done

		for i in ${!optional_specs_var}; do
			LOGFILE="${TMPDIR}/log/$(echo "${i}" | sed -e 's:/:_:' -e 's:\.spec$::').log"
			run_cmd "${LOGFILE}" "${timeprefix[@]}" catalyst -a -c "${CATALYST_CONFIG}" -f "${i}"
			if [[ $? != 0 ]]; then
				build_failure=1
				send_email "Catalyst non-fatal build error - ${i}" "" "${LOGFILE}"
				break
			else
				trigger_post_build
			fi
		done

		for i in ${!specs_var} ${!optional_specs_var}; do
			LOGFILE="${TMPDIR}/log/$(echo "${i}" | sed -e 's:/:_:' -e 's:\.spec$::')_purge.log"
			run_cmd "${LOGFILE}" "${timeprefix[@]}" catalyst --purgetmponly -c "${CATALYST_CONFIG}" -f "${i}"
		done

		update_symlinks
	done

	trigger_post_build

	if [[ ${build_failure} == 0 ]]; then
		if [[ ${lastrun} != 0 ]]; then
			stamp=$(date)
			(date -d"${stamp}" +%s; echo "${stamp}") >"${last_success_file}"
		fi

		send_email "Catalyst build success" "Build process complete."

		if [[ ${keep_tmpdir} == 0 ]]; then
			if ! rm -rf "${TMPDIR}"; then
				echo "Could not remove tmpdir ${TMPDIR}!"
				exit 1
			fi
		fi
	else
		send_email "Catalyst build complete, but with errors" "Build process has completed, but there were errors. Please consult previous emails to determine the problem."
	fi
}

main() {
	# Set pipefail so that run_cmd returns the right value in $?.
	set -o pipefail

	# Parse user arguments before we try doing container logic.
	parse_args "$@"

	(
	if [[ -n ${lock_file} ]]; then
		if ! flock -n 9; then
			echo "catalyst-auto already running"
			exit 1
		fi
	fi

	run_catalyst_commands
	) 9>"${lock_file:-/dev/null}"
}

main "$@"