#!/bin/sh

GIT_DIR=.git
dotest="$GIT_DIR/rebase-apply"

prec=4 &&
this=$(cat 2>/dev/null "$dotest/next") &&
msgnum=$(printf "%0${prec}d" $this) &&
test -f "$dotest/$msgnum" &&
message_id=$(sed -ne '
	/^[ 	]/{
		# Append continuation line
		H
		x
		s/\n//
		x
		n
	}
	# Hold this new line, and look at what is in the hold space
	x
	# Is it the Message-ID line?  If so, spit out and finish.
	/^[Mm][Ee][Ss][Ss][Aa][Gg][Ee]-[Ii][Dd]:[ 	]*/{
		s///p
		q
	}
	# Otherwise, check if this new line is empty
	x
	# Is it?  Then we are done with the header
	/^$/b end
	# Otherwise we need to hold onto this header line
	x
	# And start the next cycle
	b
: end
	q
' "$dotest/$msgnum") &&

test -n "$message_id" &&
head=$(git rev-parse --verify HEAD 2>/dev/null) &&

echo "$head $message_id" >>"$GIT_DIR"/am.log &&
GIT_NOTES_REF=refs/notes/amlog \
	git notes add -f -m "Message-Id: $message_id" "$head"