complete rewrite in golang

README.md

@@ -1,34 +0,0 @@
-# brightness
-
-Simple python script to change display brightness on active display using xrandr and xdotool.
-
-## Setup Instructions
-
-### Requirements
-
-* python3
-* xrandr
-* xdotool
-
-### Setup
-
-```sh
-git clone git@0cd.xyz:michael/brightness.git
-```
-
-create settings file with your display IDs
-
-```json
-{
-    "display0" : "DP-2",
-    "display1" : "DP-1"
-}
-```
-
-run script with
-
-```sh
-Usage: ./brightness.py [+|-]
-brightness + # increases brightness
-brightness - # decreases brightness
-```

brightness.py

@@ -1,37 +0,0 @@
-#!/usr/bin/env python3
-
-import os, sys, string, subprocess, json
-
-def main():
-    cmd = "xrandr --verbose | grep {} -A 5 | grep Brightness | cut -f 2 -d ' '".format(display())
-    brightness = float(subprocess.getoutput(cmd))
-
-    if sys.argv[1] == "+" and brightness < 1:
-        brightness += .25
-    elif sys.argv[1] == "-" and brightness > 0:
-        brightness -= .25
-    os.system("xrandr --output {} --brightness {}".format(display(), brightness))
-
-def display():
-    cmd = "xdotool getmouselocation --shell | head -n -3 | cut -d'=' -f2-"
-    cmd = subprocess.getoutput(cmd)
-    
-    #print(getDisplay()['display0']);
-
-    if int(cmd) < 2560:
-        return getDisplay()['display1']
-    return getDisplay()['display0']
-
-def getDisplay():
-    root_dir = os.path.dirname(os.path.realpath(__file__))
-    json_path = os.path.join(root_dir, 'settings.json')
-    with open(json_path, 'r') as json_data:
-        settings = json.load(json_data)
-        json_data.close()
-    return settings
-
-if len(sys.argv) <= 1:
-    print("Usage: {} [+|-]".format(sys.argv[0]))
-    sys.exit(1)
-else:
-    main()

main.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	if len(os.Args) <= 1 {
+		fmt.Printf("Usage: %s [+|-]", os.Args[0])
+		return
+	}
+	brightness()
+}
+
+func brightness() {
+	cmd := fmt.Sprintf("xrandr --verbose | grep %s -A 5 | grep Brightness | cut -f 2 -d ' '", display())
+	brightness, err := exec.Command("sh", "-c", cmd).Output()
+	if err != nil {
+		log.Fatal(err)
+	}
+	f, err := strconv.ParseFloat(strings.TrimSpace(string(brightness)), 64)
+	if err != nil {
+		log.Fatal(err)
+	}
+	switch {
+	case os.Args[1] == "+" && f < 1:
+		f += .25
+	case os.Args[1] == "-" && f > 0:
+		f -= .25
+	}
+	exe := fmt.Sprintf("xrandr --output %s --brightness %s", display(), strconv.FormatFloat(f, 'f', 2, 64))
+	exec.Command("sh", "-c", exe).Output()
+}
+
+func display() string {
+	cmd, err := exec.Command("xdotool", "getmouselocation", "--shell").CombinedOutput()
+	if err != nil {
+		log.Fatal(err)
+	}
+	lines := strings.SplitAfter(string(cmd), "\n")
+	i, err := strconv.Atoi(strings.TrimSpace(lines[0][len(lines)-3:]))
+	if err != nil {
+		log.Fatal(err)
+	}
+	switch {
+	case i < 1920:
+		return "HDMI-1"
+	case i < 4480:
+		return "DP-1"
+	default:
+		return "DP-2"
+	}
+}