#!/bin/sh

no_build=false
start_from=""

while getopts 'ns:' opt; do
	case "$opt" in
	n)
		no_build=true
		;;
	s)
		if [ -f "$SHA1_FILE" ]; then
			printf '%s: %s exists, so -s is invalid\n' "$0" "$SHA1_FILE" 1>&2
			exit 1
		fi
		start_from="$OPTARG"
		;;
	*)
		exit 1
		;;
	esac
done
shift $((OPTIND - 1))

tools_dir=$(dirname "$0")
. "$tools_dir/common.sh"

log()
{
	echo "$@" | tee -a "$LOG_FILE"
}

execute()
{
	log '$' "$@"
	_out="$( "$@" 2>&1 )"
	_err=$?
	echo "$_out" | tee -a "$LOG_FILE"
	return "$_err"
}

report()
{
	if [ -n "$1" ]; then
		linux-next-notify "$1"
	fi
	if [ -n "$2" ]; then
		printf '%s\n' "$2" 1>&2
	fi
}

fix_up()
{
	report "$@"
	if ! bash -i; then
		exit
	fi
}

if [ -f "$SHA1_FILE" ]; then
	previous_tree=$(tail -n1 "$SHA1_FILE" | cut -f1 -d"$_TAB")
elif [ -z "$start_from" ]; then
	cp /dev/null "$LOG_FILE"
	execute date -R
	execute git checkout master
	execute git reset --hard stable
	printf 'Name\t\tSHA1\n----\t\t----\n' > "$SHA1_FILE"
fi

heads=$(awk -F '\t' '
	/^#/ { next; }
	$2=="git" { printf("git/%s/%s ", $3, $5); }
	$2=="branch" { printf("branch/%s ", $1); }
	$2=="switch" { printf("switch/%s/%s ", $3, $4); }' "$CTRL_FILE")

need_build=false

for h in $heads; do
	op=${h%%/*}
	args=${h#*/}
	arg1=${args%%/*}
	arg2=${args#*/}

	if [ -n "$previous_tree" ]; then
		if [ "$op" = 'git' ] && [ "$arg1" = "$previous_tree" ]; then
			previous_tree=''
		fi
		continue
	elif [ -n "$start_from" ]; then
		if [ "$op" = 'git' ] && [ "$arg1" = "$start_from" ]; then
			start_from=""
		else
			continue
		fi
	fi

	if [ "$op" = "branch" ]; then
		git branch -f "$arg1"
		linux-next-notify "update branch $arg1"
		continue
	fi

	if [ "$op" = 'switch' ]; then
		new_branch=$arg1
		if [ "$new_branch" = 'master' ]; then
			old_branch=$(git branch --show-current)
			if ! [ "$old_branch" = 'master' ]; then
				if ! git checkout master; then
					fix_up 'git checkout master failed'
				fi
			fi
		else
			base=$arg2
			if ! git checkout -B "$new_branch" "$base"; then
				fix_up "git checkout $new_branch failed"
			fi
		fi
		continue
	fi

# $op == "git"

	tree=$arg1
	branch=$arg2
	h="$tree${branch:+/$branch}"
	hlog=$(git log -1 --oneline "$h") 2>/dev/null
	old_head=$(git rev-parse HEAD)
	if [ -f "../pre-merge/$tree" ]; then
		while read -r p <&7; do
			if ! "$bin_dir/do_patch" -n "$p"; then
				fix_up "premerge patch failed"
			fi 7<&-
		done 7<"../pre-merge/$tree"
	fi
	log Merging "$h" "($hlog)"
	check_dups "$tree" HEAD "$h" | tee -a "$LOG_FILE"
	msg=$(printf "Merge branch '%s' of %s" "${branch:-$tree}" "$(get_url "$tree")")
	if ! execute git merge -m "$msg" "$h"; then
		echo Merge failed 1>&2
		echo "$h" >>../merge.debug
		git diff >>../merge.debug 2>&1

		check_unmerged_files "$tree"

		if git diff 2>&1 | grep -E -q '<<<<<|^\*'; then
			if [ -f "../merge-fixes/$tree" ]; then
				echo "Merge fixes exist for this tree:"
				cat "../merge-fixes/$tree"
			fi
			fix_up "new conflict found merging $tree"
		fi
#		if [ "$(git status --porcelain)" ]; then
			if ! execute git commit --no-edit -v -a; then
				fix_up "next commit failed for $tree"
			fi
			execute git diff -M --stat --summary 'HEAD^..'
#		fi
	fi

	tab="$_TAB"
	if [ "${#tree}" -lt 8 ]; then
		tab="$_TAB$_TAB"
	fi
	printf '%s%s%s\n' "$tree" "$tab" "$(git rev-parse "$h^{}")" >> "$SHA1_FILE"

	if [ -f "../merge-fixes/$tree" ]; then
		while read -r p <&7; do
			if ! "$bin_dir/merge_fix" -n "$p"; then
				fix_up "merge fix failed for $tree"
			fi 7<&-
		done 7<"../merge-fixes/$tree"
	fi

	if $no_build; then
		continue
	fi

	if ! $need_build; then
		# See if we need to build after merging this tree
		if [ -n "$(git diff "$old_head"..)" ]; then
			need_build=true
		fi
	fi
	if ! $need_build; then
		continue
	fi

	if [ "$(get_build_flag "$tree")" != "yes" ]; then
		if ! [ -f "$top_dir/old-versions/$tree" ]; then
			continue
		fi
	fi

	repo="${build_host:+$build_host:}${build_dir}"
	if ! git push -f "$repo" HEAD:refs/heads/next; then
		fix_up "push failed for $tree" "git push failed"
	fi

	if [ -x "../pre-build/$tree" ] &&
	   ! "../pre-build/$tree"; then
		fix_up "pre-build script failed for $tree" "Prebuild script failed"
	fi
	if ! "$bin_dir/do_build" "$tree"; then
		report "build failed for $tree" "Build failed - run do_merge when fixed"
		exit 1
	fi

	rm -f "$top_dir/old-versions/$tree"

	need_build=false
done

exit 0