Refactor and add cache

Makefile

@@ -13,7 +13,7 @@ $(INSTALL_PATH): cbattery
 
 uninstall:
 	@echo "Removing cbattery from $(DESTDIR)"
-	@$(DESTDIR)/cbattery revert || (echo "Reverting cbattery configurations failed"; exit 1)
+	@su $(USER) -c '$(DESTDIR)/cbattery revert' || (echo "Reverting cbattery configurations failed"; exit 1)
 	@rm -f $(INSTALL_PATH)
 
 help:

cbattery

@@ -2,7 +2,9 @@
 
 set -e
 
-function usage() {
+CACHE_FILE="${XDG_CACHE_HOME:-$HOME/.cache}/cbattery.status"
+
+usage() {
     cat << EOF
 usage: ${0##*/} [command]
     charging [on|off]		- Toggle charging
@@ -14,48 +16,53 @@ usage: ${0##*/} [command]
 EOF
 }
 
-function enable_discharging() {
+write_cache() {
+    echo "$1" > "$CACHE_FILE"
+}
+
+read_cache() {
+    cat "$CACHE_FILE" 2> /dev/null
+}
+
+enable_discharging() {
     echo "Enabling battery discharging"
     sudo smc -k CH0I -w 01
 }
 
-function disable_discharging() {
+disable_discharging() {
     echo "Disabling battery discharging"
     sudo smc -k CH0I -w 00
 }
 
-function enable_charging() {
+enable_charging() {
     echo "Enabling battery charging"
     sudo smc -k CH0B -w 00
     sudo smc -k CH0C -w 00
     disable_discharging
+    write_cache "enabled"
 }
 
-function disable_charging() {
+disable_charging() {
     echo "Disabling battery charging"
     sudo smc -k CH0B -w 02
     sudo smc -k CH0C -w 02
+    write_cache "disabled"
 }
 
-function get_smc_charging_hex() {
+get_smc_charging_hex() {
     smc -k CH0B -r | awk '{print $4}' | sed s:\)::
 }
 
-function get_smc_charging_status() {
+get_smc_charging_status() {
     hex_status=$(get_smc_charging_hex)
-	if [[ "$hex_status" == "00" ]]; then
-		echo "enabled"
-	else
-		echo "disabled"
-	fi
+    [[ "$hex_status" == "00" ]] && echo "enabled" || echo "disabled"
 }
 
-function get_battery_percentage() {
-	battery_percentage=$(pmset -g batt | tail -n1 | awk '{print $3}' | sed s:%\;::)
-	echo "$battery_percentage"
+get_battery_percentage() {
+    pmset -g batt | awk 'END {print $3}' | sed 's/%;//'
 }
 
-function install_visudo_file() {
+install_visudo_file() {
     sudoers_file="/private/etc/sudoers.d/cbattery"
     if ! smc_loc="$(command -v smc)"; then
 	echo "'smc' is required but not found."
@@ -70,51 +77,64 @@ function install_visudo_file() {
     sudo chmod 440 "$sudoers_file"
 }
 
-action=$1
-setting=$2
-
-if [ -z "$action" ] || [[ "$action" == "help" ]]; then
-	usage
-	exit 0
-fi
-
-if [[ "$action" == "revert" ]]; then
-	enable_charging
-	disable_discharging
-	exit 0
-fi
-
-if [[ "$action" == "charging" ]]; then
-	echo "Setting $action to $setting"
-	if [[ "$setting" == "on" ]]; then
-		enable_charging
-	elif [[ "$setting" == "off" ]]; then
-		disable_charging
-	fi
-	exit 0
-fi
-
-if [[ "$action" == "adapter" ]]; then
-	echo "Setting $action to $setting"
-	if [[ "$setting" == "on" ]]; then
-		enable_discharging
-	elif [[ "$setting" == "off" ]]; then
-		disable_discharging
-	fi
-	exit 0
-fi
-
-if [[ "$action" == "status" ]]; then
-	if [[ "$setting" == "charging" ]]; then
-		exit "$(get_smc_charging_hex)"
+get_cached_status() {
+    set +e
+    read_cache_result=$(read_cache)
+    read_cache_error=$?
+    set -e
+    if [ $read_cache_error -ne 0 ]; then
+        status=$(get_smc_charging_status)
+        write_cache "$status"
+        echo "$status"
     else
-		echo "Battery at $(get_battery_percentage)%, smc charging $(get_smc_charging_status)"
+        echo "$read_cache_result"
     fi
-	exit 0
-fi
+}
 
-if [[ "$action" == "visudo" ]]; then
+runScript() {
+    action=$1
+    setting=$2
+
+    case "$action" in
+        "help" | "")
+            usage
+            ;;
+        "revert")
+            enable_charging
+            disable_discharging
+            ;;
+        "charging")
+            echo "Setting $action to $setting"
+            case "$setting" in
+                "on") enable_charging ;;
+                "off") disable_charging ;;
+                *) echo "Invalid option: $setting" ;;
+            esac
+            ;;
+        "adapter")
+            echo "Setting $action to $setting"
+            case "$setting" in
+                "on") enable_discharging ;;
+                "off") disable_discharging ;;
+                *) echo "Invalid option: $setting" ;;
+            esac
+            ;;
+        "status")
+            case "$setting" in
+                "charging") exit "$(get_smc_charging_hex)" ;;
+                "cache") echo "$(get_cached_status)" ;;
+                *) echo "Battery at $(get_battery_percentage)%, smc charging $(get_smc_charging_status)" ;;
+            esac
+            ;;
+        "visudo")
             install_visudo_file
-	exit 0
-fi
+            ;;
+        *)
+            echo "Invalid command: $action"
+            usage
+            ;;
+    esac
+}
+
+runScript "$@"