Add encryption support with GPG for Levelhead emails

check-levels

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-# Define RUMPUS_DELEGATION_KEY and SEND_ADDR
+# Define RUMPUS_DELEGATION_KEY, SEND_ADDR, and optionally USE_GPG
 RCFILE="$(dirname $0)/.checklevelsrc"
 
 if [ -f $RCFILE ]; then
@@ -30,5 +30,30 @@ LEVEL_TITLE=$(jq -r '.title' <<< $LEVEL)
 echo "Found new level: $LEVEL_TITLE ($LEVEL_ID) by $LEVEL_CREATOR!" >> $COMPOSE
 done <<< $LEVELS
 
-mail -s "New Levelhead Levels" $SEND_ADDR < $COMPOSE
+if [ ! -z "$USE_GPG" ]
+then
+gpg --refresh-keys
+sendmail $SEND_ADDR <<EOF
+Subject: New Levelhead Levels
+Content-Type: multipart/encrypted;
+  protocol="application/pgp-encrypted";
+  boundary="contentboundary"
+
+This message is encrypted with PGP/MIME.
+--contentboundary
+Content-Type: application/pgp-encrypted
+
+Version: 1
+
+--contentboundary
+Content-Type: application/octet-stream; name="encrypted.asc"
+
+$(gpg --batch --armor --recipient "$SEND_ADDR" -o- --encrypt "$COMPOSE")
+
+--contentboundary--
+EOF
+else
+mail -s "New Levelhead Levels" "$SEND_ADDR" < "$COMPOSE"
+fi
+
 rm $COMPOSE