Rewrite brightness script

home/.config/xmonad/xmonad.hs

@@ -197,13 +197,13 @@ myKeys =
     , ("<XF86AudioMute>",           spawn "pulsemixer --toggle-mute")
     , ("<XF86AudioLowerVolume>",    spawn "pulsemixer --change-volume -5")
     , ("<XF86AudioRaiseVolume>",    spawn "pulsemixer --change-volume +5")
-    , ("<XF86MonBrightnessUp>",     spawn "brightness + 5 %")
+    , ("<XF86MonBrightnessUp>",     spawn "brightness -i 5%")
-    , ("<XF86MonBrightnessDown>",   spawn "brightness - 5 %")
+    , ("<XF86MonBrightnessDown>",   spawn "brightness -d 5%")
     -- Map media keys to meta + arrows for keyboards without special keys
     , ("M-<Down>",                  spawn "pulsemixer --change-volume -5")
     , ("M-<Up>",                    spawn "pulsemixer --change-volume +5")
-    , ("M-<Right>",                 spawn "brightness + 5 %")
+    , ("M-<Right>",                 spawn "brightness -i 5%")
-    , ("M-<Left>",                  spawn "brightness - 5 %")
+    , ("M-<Left>",                  spawn "brightness -d 5%")
     ]
         where nonNSP            = WSIs (return (\ws -> W.tag ws /= "NSP"))
               nonEmptyNonNSP    = WSIs (return (\ws -> isJust (W.stack ws) && W.tag ws /= "NSP"))

home/.local/bin/scripts/brightness

@@ -1,63 +1,153 @@
 #!/bin/sh
 
-BRIGHTNESS_FILE="/sys/class/backlight/intel_backlight/brightness"
-BRIGHTNESS_MAX=937
 
-function change_brightness() {
+# Parse arguments
-    BRIGHTNESS=$(cat $BRIGHTNESS_FILE)
+# ------------------------------------------------------------------------------------
+BRIGHTNESS_DIR="/sys/class/backlight/*"
+SEND_NOTIFICATION=0
+URGENCY="normal"
+INCREASE=0
+DECREASE=0
+SET=0
+BRIGHTNESS=0
 
-    change_value=$2
+while [ "$1" ]; do
+    case "$1" in
+        -h | --help)
+            cat << EOF
+brightness is a cli tool that for displaying or modifying screen brightness.
 
-    # If we're dealing with percentages, convert to absolutes
+Options:
-    if [ $3 == "%" ]; then
+-h | --help: Display this message
-        change_value=$((($BRIGHTNESS_MAX / 100) * $change_value))
+-n | --notification: Produce a desktop notification with brightness info
-    elif [ $3 == "#" ]; then
+-N | --no-notification: Don't produce a desktop notification with brightness info
-        change_value=$change_value
+-u | --urgency [URGENCY]: Pass over notify-send urgency attribute (default: normal)
-    else
+-i | --increase [BRIGHTNESS]: Increase the brightness by given amount
-        echo "Invalid unit, options: [% - percent, # - absolute], default: %"
+-d | --decrease [BRIGHTNESS]: Decrease the brightness by given amount
+-s | --set [BRIGHTNESS]: Set new brightness level
+-p | --path [DIR_PATH]: Path to brightness directory (default: /sys/class/backlight/*)
+
+Valid values:
+    URGENCY: low, normal, critical
+    DIR_PATH: Valid path to a directory
+    BRIGHTNESS:
+        specific value - Example: 10
+        percentage value - Example: 10%
+EOF
+            exit 0
+            ;;
+        -n | --notification)
+            SEND_NOTIFICATION=1
+            ;;
+        -N | --no-notification)
+            SEND_NOTIFICATION=0
+            ;;
+        -u | --urgency)
+            URGENCY="$2"
+            shift
+            ;;
+        -i | --increase)
+            INCREASE=1
+            BRIGHTNESS="$2"
+            shift
+            ;;
+        -d | --decrease)
+            DECREASE=1
+            BRIGHTNESS="$2"
+            shift
+            ;;
+        -s | --set)
+            SET=1
+            BRIGHTNESS="$2"
+            shift
+            ;;
+        -p | --path)
+            BRIGHTNESS_DIR="$2"
+            shift
+            ;;
+        * ) 
+            echo "Unknown argument '$1', use -h or --help for help" 
             exit 1
+            ;;
+    esac
+    shift
+done
+
+# Define constants based on parsed arguments
+# ------------------------------------------------------------------------------------
+BRIGHTNESS_FILE="$BRIGHTNESS_DIR/brightness"
+BRIGHTNESS_MAX="$(cat $BRIGHTNESS_DIR/max_brightness)"
+
+
+# Helper functins
+# ------------------------------------------------------------------------------------
+
+# Send brightness level desktop notification, showing the given brightness level
+# as progress bar, along with given message.
+# $1 - brightness level (number 0-100)
+# $2 - message (notification body)
+send_brightness_notify() {
+    percent_brightness="$1"
+    msg="$2"
+
+    notify-send \
+        --app-name=brightness \
+        --urgency="$URGENCY" \
+        -h int:value:$percent_brightness \
+        -h string:synchronous:brightness \
+        "brightness" "$msg"
+}
+
+
+# Set brightness to given absolute value
+# $1 - brightness absolute value
+set_brightness() {
+    # there should be sudo config allowing this command without password
+    echo "$1" | sudo tee $BRIGHTNESS_FILE >/dev/null
+}
+
+
+# Main Logic
+# ------------------------------------------------------------------------------------
+
+# Determine the absolute new brightness level
+if [ $INCREASE -eq 1 ] || [ $DECREASE -eq 1 ] || [ $SET -eq 1 ]; then
+    # If we're dealing with percentages, change to absolutes
+    if echo "$BRIGHTNESS" | grep -qE '%$'; then
+        numeric=$(echo "$BRIGHTNESS" | sed 's/.$//')
+        absolute=$(echo "($BRIGHTNESS_MAX / 100) * $numeric" | bc -l)
+        BRIGHTNESS=$(printf "%.0f" $absolute)
     fi
 
-    # Increment or decrement based on first arg
+    # Get the new requested absolute brightness
-    if [ $1 == "+" ]; then
+    if [ $SET -eq 1 ]; then
-        new_brightness=$(($BRIGHTNESS + $change_value))
+        new_brightness=$BRIGHTNESS
-    elif [ $1 == "-" ]; then
+    elif [ $DECREASE -eq 1 ]; then
-        new_brightness=$(($BRIGHTNESS - $change_value))
+        cur_brightness=$(cat $BRIGHTNESS_FILE)
+        new_brightness=$(($cur_brightness - $BRIGHTNESS))
     else
-        echo "Invalid operator, options: [+, -]"
+        cur_brightness=$(cat $BRIGHTNESS_FILE)
-        exit 1
+        new_brightness=$(($cur_brightness + $BRIGHTNESS))
     fi
 
-    # Make sure we respect min/max boundaries
+    # Ensure we respect max/min boundaries
     if [ $new_brightness -lt 0 ]; then
         new_brightness=0
     elif [ $new_brightness -gt $BRIGHTNESS_MAX ]; then
         new_brightness=$BRIGHTNESS_MAX
     fi
 
-    # Write the brightness (sudo shouldn't require password here)
+    # Update the brightness
-    echo $new_brightness | sudo tee $BRIGHTNESS_FILE
+    set_brightness $new_brightness
-}
-
-if [ $# -ge 1 ] && [ "$1" == "+" ] || [ "$1" == "-" ]; then
-    if [ $# -lt 2 ]; then
-        change_value=5 # Default to 5%
-    else
-        change_value=$2
 fi
 
-    if [ $# -lt 3 ]; then
+cur_brightness=$(cat $BRIGHTNESS_FILE)
-        unit="%"
+percent_brightness=$(echo "($cur_brightness / $BRIGHTNESS_MAX) * 100" | bc -l)
-    else
+percent_brightness_2f=$(printf "%.2f" $percent_brightness)
-        unit=$3
+percent_brightness_rounded=$(printf "%.0f" $percent_brightness)
-    fi
+
-    change_brightness $1 $change_value $unit > /dev/null
+if [ $SEND_NOTIFICATION -eq 1 ]; then
+    send_brightness_notify "$percent_brightness_rounded" "Level: $percent_brightness_rounded"
 fi
 
-# Display new brightness
+echo "Brightness: ${percent_brightness_2f}% (absolute: $cur_brightness)"
-
-BRIGHTNESS=$(cat $BRIGHTNESS_FILE)
-BRIGHTNESS_PERCENT=$(echo "($BRIGHTNESS / $BRIGHTNESS_MAX) * 100" | bc -l)
-BRIGHTNESS_PERCENT=$(printf "%.2f" $BRIGHTNESS_PERCENT)
-
-echo "Brightness: ${BRIGHTNESS_PERCENT}% (absolute: $BRIGHTNESS)"