#!/bin/sh
# mencrypt PLAINMSG - generate a PGP/MIME signed and encrypted message

[ -f "$1" ] || exit 1

IFS='
'
FLAGS=$(maddr -a -h from:to:cc:bcc: "$1" |sort -u |sed 's/^/--recipient=/')

FROM=$(maddr -a -h from "$1" | sed 1q)
[ "$FROM" ] && key="--default-key=$FROM"

if command -v gpg2 >/dev/null; then
	GPG=gpg2
else
	GPG=gpg
fi

TMPD=$(mktemp -d -t mencrypt.XXXXXX)
trap "rm -rf '$TMPD'" INT TERM EXIT

awk '/^$/,0' "$1" |
	mmime |
	$GPG "$key" --armor --encrypt --sign $FLAGS -o "$TMPD/msg.asc" ||
	exit $?

printf 'Version: 1\n' >"$TMPD/version"

{
	sed '/^$/q' "$1"
	printf '#application/pgp-encrypted %s/version\n' "$TMPD"
	printf '#application/octet-stream %s/msg.asc\n' "$TMPD"
} |
	mmime -t 'multipart/encrypted; protocol="application/pgp-encrypted"'