fix: load config on macOS

On macOS, `os.UserConfigDir` returns `$HOME/Library/Application Support`
and not `~/.config`. This patch uses a module that works across OSes.

Fixes mattn#3

go.mod

@@ -4,6 +4,7 @@ go 1.20
 
 require (
 	github.com/fatih/color v1.15.0
+	github.com/mitchellh/go-homedir v1.1.0
 	github.com/nbd-wtf/go-nostr v0.15.1
 	github.com/urfave/cli/v2 v2.25.0
 )

go.sum

@@ -20,6 +20,8 @@ github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovk
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.18 h1:DOKFKCQ7FNG2L1rbrmstDN4QVRdS89Nkh85u68Uwp98=
 github.com/mattn/go-isatty v0.0.18/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
+github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/nbd-wtf/go-nostr v0.15.1 h1:a3lGlEVNOtXpxv8VA3+rdtX5PCoYKXKAOpcr4cQFgO8=
 github.com/nbd-wtf/go-nostr v0.15.1/go.mod h1:qFFTIxh15H5GGN0WsBI/P73DteqsevnhSEW/yk8nEf4=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=

main.go

@@ -9,12 +9,14 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"runtime"
 	"sort"
 	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
 
+	"github.com/mitchellh/go-homedir"
 	"github.com/urfave/cli/v2"
 
 	"github.com/fatih/color"
@@ -60,8 +62,22 @@ type Profile struct {
 	Name        string `json:"name"`
 }
 
+func configDir() (string, error) {
+	switch runtime.GOOS {
+	case "darwin":
+		dir, err := homedir.Dir()
+		if err != nil {
+			return "", err
+		}
+		return filepath.Join(dir, ".config"), nil
+	default:
+		return os.UserConfigDir()
+
+	}
+}
+
 func loadConfig(profile string) (*Config, error) {
-	dir, err := os.UserConfigDir()
+	dir, err := configDir()
 	if err != nil {
 		return nil, err
 	}