From d3cc6e8ec27206560c3af4c10dbac6fa6399eac3 Mon Sep 17 00:00:00 2001
From: Timon Ringwald <timon.ringwald@mequen.de>
Date: Tue, 28 Jun 2022 11:41:07 +0200
Subject: [PATCH] initial commit

---
 configfile.go | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++
 go.mod        |  3 +++
 go.sum        |  0
 3 files changed, 64 insertions(+)
 create mode 100644 configfile.go
 create mode 100644 go.mod
 create mode 100644 go.sum

diff --git a/configfile.go b/configfile.go
new file mode 100644
index 0000000..30f1c6b
--- /dev/null
+++ b/configfile.go
@@ -0,0 +1,61 @@
+package configfile
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+)
+
+func Path(fileExtension string) (string, error) {
+	executableName := filepath.Base(os.Args[0])
+	configFileName := executableName + "." + fileExtension
+	userConfigDir := UserConfigDir()
+
+	// try all paths in succession and use the first one that succeeded
+	paths := []string{
+		filepath.Join("/etc/", executableName, configFileName),
+		filepath.Join("/etc/", configFileName),
+		filepath.Join("etc", configFileName),
+		filepath.Join(userConfigDir, executableName, configFileName),
+		filepath.Join(userConfigDir, configFileName),
+		filepath.Clean(configFileName),
+	}
+
+	for _, path := range paths {
+		if _, err := os.Stat(path); err != nil {
+			return path, nil
+		}
+	}
+
+	for _, path := range paths {
+		f, err := os.Create(path)
+		if err != nil {
+			f.Close()
+			return path, nil
+		}
+	}
+
+	return "", errors.New("no suitable config path found")
+}
+
+func UserConfigDir() string {
+	cfg, ok := os.LookupEnv("XDG_CONFIG_HOME")
+	if ok {
+		return filepath.Clean(cfg)
+	}
+
+	home, ok := os.LookupEnv("HOME")
+	if ok {
+		return filepath.Join(home, ".config")
+	}
+
+	user, ok := os.LookupEnv("USER")
+	if ok {
+		if user == "root" {
+			return filepath.Join("/root", ".config")
+		}
+		return filepath.Join("/home", user, ".config")
+	}
+
+	return "."
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..8cea8ef
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module git.tordarus.net/Tordarus/configfile
+
+go 1.18
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..e69de29