Add cli arg-parsing and usage message

mkdeck.sh

@@ -6,9 +6,38 @@
 # Date:
 #―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
 
+FRENCH_CARDS="♣♚ ♣♛ ♣♝ ♠♚ ♠♛ ♠♝ ♢♔ ♢♕ ♢♗ ♡♔ ♡♕ ♡♗ 🃏 🃏"
 FRENCH_SUITS="♣ ♢ ♡ ♠"
 FRENCH_SUIT_CARDS="A 2 3 4 5 6 7 8 9 10"
-FRENCH_ADDITIONAL_CARDS="♣♚ ♣♛ ♣♝ ♠♚ ♠♛ ♠♝ ♢♔ ♢♕ ♢♗ ♡♔ ♡♕ ♡♗ 🃏 🃏"
+
+
+usage() {
+	echo "usage: $(basename "$0") [-h] [-d DECK_PREFIX] DIRECTORY"
+	echo
+	echo "$(basename "$0") creates a directory representing a card-deck."
+	echo 'That is, it creates empty files representing the decks’ cards,'
+	echo 'with the files’ names corresponding to their card in the deck.'
+	echo
+	echo '  -d             specify the deck-prefix to use'
+	echo '  -h             print this message and exit'
+	echo
+	echo 'A deck-prefix is the name of the deck, and determines the'
+	echo 'variables that will be used to determine the deck’s cards.'
+	echo 'For instance, if the deck-prefix is FRENCH — the deck'
+	echo 'hard-coded echo "into $(basename "$0") — then the variables'
+	echo 'FRENCH_CARDS, FRENCH_SUITS, and FRENCH_SUIT_CARDS will be used.'
+	echo
+	echo '$NAME_CARDS contains a space-delimited list of strings of raw'
+	echo 'card-names, like: “♣♚ ♢♔ 🃏”'
+	echo '$NAME_SUITS contains a list of suits, like: “♣ ♡”'
+	echo '$NAME_SUIT_CARDS containts a list of cards each suit has, for'
+	echo 'example: “1 2 3 4”'
+    echo
+	echo 'You can define a deck simply using $NAME_CARDS, or you can use'
+    echo '$NAME_SUITS and $NAME_SUITS_CARDS to help reduce repetiton on'
+    echo 'your part. Substitute “NAME” with your preferred deck-name.'
+}
+
 
 shell_sanitize() {
 	local str="$1"
@@ -19,7 +48,7 @@ shell_sanitize() {
 
 suit_cards() {
 	local name="$(shell_sanitize "$1")"
-	local suits=n"$(eval "echo \$${name}_SUITS")"
+	local suits="$(eval "echo \$${name}_SUITS")"
 	local suit_cards="$(eval "echo \$${name}_SUIT_CARDS")"
 
 	for suit in $suits; do
@@ -28,7 +57,7 @@ suit_cards() {
 		done
 	done
 
-	eval "echo \$${name}_ADDITIONAL_CARDS"
+	eval "echo \$${name}_CARDS"
 }
 
 
@@ -52,7 +81,7 @@ mkdeck_cards() {
 
 	if test -z "$cards"; then
 		1>&2 echo "No cards found for deck $deck_name. Check your environment variables:"
-		1>&2 echo "${deck_name}_SUITS, ${deck_name}_SUIT_CARDS, and ${deck_name}_ADDITIONAL_CARDS."
+		1>&2 echo "${deck_name}_CARDS, ${deck_name}_SUITS, and ${deck_name}_SUIT_CARDS."
 		exit 3
 	fi
 
@@ -70,4 +99,26 @@ mkdeck() {
 }
 
 
-mkdeck "$1" "FRENCH"
+DECK="$FRENCH"
+while getopts 'hd:' arg; do
+	case $arg in
+		h)
+			usage
+			exit 0
+			;;
+		d)
+			DECK="$OPTARG"
+			;;
+	esac
+done
+
+shift $((OPTIND-1))
+
+CARD_DIR="$1"
+
+if test -z "$CARD_DIR"; then
+	usage 1>&2
+	exit 4
+fi
+
+mkdeck "$CARD_DIR" "$DECK"