#!/bin/bash

LOG_FILE="../merge.log"
build_host="sprygo"
build_dir="/scratch/sfr/next"
build_cmd="bin/build_next"

no_build=false
start_from=""

[ "$1" = "-n" ] && {
	shift
	no_build=true
}
[ "$1" = "-s" ] && {
	shift
	start_from="$1"
	[ -z "$start_from" ] && {
		echo "-s requires a start tree" 1>&2
		exit 1
	}
	shift
}
[ -n "$1" ] && build_host="$1"

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

execute()
{
	log "$" $@
	$@ 2>&1 | tee -a $LOG_FILE
	return ${PIPESTATUS[0]}
}

[ -n "$start_from" ] || {
	cp /dev/null $LOG_FILE
	execute git checkout master
	execute git reset --hard stable
}

heads=$(grep -v '^#' ../real_control | awk -F '	' '$2=="quilt" { printf("quilt/%s ", $3); } $2=="git" { printf("%s/%s ", $3, $5); }')

need_build=false

for h in $heads; do
	tree=${h%/*}
	[ "$tree" == "quilt" ] && tree=${h#quilt/}

	[ -n "$start_from" ] && {
		if [ "$tree" = "$start_from" ]; then
			start_from=""
		else
			continue
		fi
	}

	log Merging $h
	old_head=$(git rev-parse HEAD)
	execute git merge $h || {
		echo Merge failed 1>&2
		bash -i || exit
		GIT_EDITOR=: execute git commit -v -a
		execute git diff -M --stat --summary 'HEAD^..'
	}
	$no_build && continue
	$need_build || {
		# See if we need to build after merging this tree
		new_head=$(git rev-parse HEAD)
		[ "$old_head" = "$new_head" ] ||
			need_build=true
		$need_build || 
			[ "$(git diff ${old_head}.. | wc -c)" -eq 0 ] ||
			need_build=true
	}
	$need_build ||
		continue
	do_build=$(grep -v '^#' ../real_control | awk -F '	' '$3=="'$tree'" { print $6; }')
	[ "$do_build" = "yes" ] ||
		continue
	rsync -avH --exclude .git --delete . "$build_host":"$build_dir"/. || {
		echo Rsync failed 1>&2
		bash -i || exit
	}
	ssh "$build_host" "$build_cmd" || {
		echo Build failed 1>&2
		bash -i || exit
	}
	need_build=false
done

exit 0