packages/easyscan: allow overriding easyscan options

nix/packages/by-name/easyscan/easyscan.sh

@@ -1,11 +1,51 @@
+#!/usr/bin/env bash
 # This is here because scanimage's batch mode is broken for my scanner
 
-OUTPUT_FILE="${1:-./scan_"$(date)".pdf}"
+function help() {
+	cat <<EOF
+easyscan
 
+easyscan wraps scanimage and joins the resulting pdf.
+
+Usage:
+easyscan <target_file> [ -- args ]:
+	Scan a (multi-page) document to <target_file>, passing args to scanimage
+EOF
+}
+
+if [ $# -lt 1 ]; then
+	help
+	exit 1
+fi
+OUTPUT_FILE="$1.pdf"
 if [ -e "$OUTPUT_FILE" ]; then
 	echo "$OUTPUT_FILE" already exists, you are probably making a mistake!
 	exit 1
 fi
+shift
+
+scanimage_args=(
+	"-x" "210"
+	"-y" "297"
+	"--resolution" "300"
+)
+
+while [ $# -gt 0 ]; do
+	case $1 in
+	--help)
+		help
+		exit
+		;;
+	--)
+		shift
+		scanimage_args+=("$@")
+		break
+		;;
+	*)
+		shift
+		;;
+	esac
+done
 
 tempdir="$(mktemp -d)"
 filenames=()
@@ -26,11 +66,7 @@ while :; do
 
 	# If no size is set, the output will be wonky-sized
 	# 210,297 is the size of A4
-	scanimage -x 210 -y 297 --resolution 300 -o "$CUR_FNAME" >/dev/null 2>&1 ||
-		{
-			echo "Failed to scan page..."
-			ok="false"
-		}
+	scanimage "${scanimage_args[@]}" -o "$CUR_FNAME" || ok="false"
 
 	if $ok; then
 		counter=$((counter += 1))