✨ Add support for enabling a monospace editor font via an environment variable or configuration file.

main.go

@@ -9,6 +9,7 @@ import (
 	"image/color"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"fyne.io/fyne/v2"
 	"fyne.io/fyne/v2/app"
@@ -89,6 +90,31 @@ func isReadonly() bool {
 	return os.Getenv("READONLY") == "true"
 }
 
+// fixedPitchEnabled reports whether the user opted into a monospace
+// (programmer) font. The value comes from the TINY_ENCRYPT_ENABLE_FIXED_PITCH
+// environment variable; when that is unset it falls back to the file at
+// ~/.config/envs/TINY_ENCRYPT_ENABLE_FIXED_PITCH (content trimmed). The values
+// true/on/yes/1 are accepted, case-insensitively.
+func fixedPitchEnabled() bool {
+	v := os.Getenv("TINY_ENCRYPT_ENABLE_FIXED_PITCH")
+	if v == "" {
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return false
+		}
+		data, err := os.ReadFile(filepath.Join(home, ".config", "envs", "TINY_ENCRYPT_ENABLE_FIXED_PITCH"))
+		if err != nil {
+			return false
+		}
+		v = strings.TrimSpace(string(data))
+	}
+	switch strings.ToLower(v) {
+	case "true", "on", "yes", "1":
+		return true
+	}
+	return false
+}
+
 // windowConfig is persisted to ~/.cache/secure-editor-go-config.json so the
 // editor remembers its window size across runs.
 type windowConfig struct {
@@ -246,6 +272,10 @@ func main() {
 
 	textEntry := widget.NewMultiLineEntry()
 	textEntry.Wrapping = fyne.TextWrapWord
+	if fixedPitchEnabled() {
+		// Use Fyne's bundled monospace font for a programmer-style editor.
+		textEntry.TextStyle = fyne.TextStyle{Monospace: true}
+	}
 
 	initialText := string(plaintext)
 	textEntry.SetText(initialText)