Fix ANSI escapes (on Windows) not being interpreted after using GPG pinentry

src/backend/2globalsUNIX.go

@@ -12,3 +12,9 @@ const (
 	PathSeparator = "/"
 	IsWindows     = false
 )
+
+// enableVirtualTerminalProcessing is a dummy function on UNIX-like systems (only needed on Windows)
+// TODO remove after migration off of GPG, as pinentry is responsible for disabling ANSI escape sequence interpretation
+func enableVirtualTerminalProcessing() {
+	return
+}

src/backend/2globalsWIN.go

@@ -2,6 +2,11 @@
 
 package backend
 
+import (
+	"os"
+	"syscall"
+)
+
 // EntryRoot path to libmutton entry directory
 var EntryRoot = Home + "\\AppData\\Local\\libmutton\\entries"
 var ConfigDir = Home + "\\AppData\\Local\\libmutton\\config"
@@ -12,3 +17,15 @@ const (
 	PathSeparator = "\\"
 	IsWindows     = true
 )
+
+// enableVirtualTerminalProcessing ensures ANSI escape sequences are interpreted properly on Windows
+// TODO remove after migration off of GPG, as pinentry is responsible for disabling ANSI escape sequence interpretation
+func enableVirtualTerminalProcessing() {
+	stdout := syscall.Handle(os.Stdout.Fd())
+
+	var originalMode uint32
+	syscall.GetConsoleMode(stdout, &originalMode)
+	originalMode |= 0x0004
+
+	syscall.MustLoadDLL("kernel32").MustFindProc("SetConsoleMode").Call(uintptr(stdout), uintptr(originalMode))
+}

src/backend/gpg.go

@@ -13,11 +13,16 @@ import (
 func DecryptGPG(targetLocation string) []string {
 	cmd := exec.Command("gpg", "--pinentry-mode", "loopback", "-q", "-d", targetLocation)
 	output, err := cmd.Output()
+
+	// ensure ANSI escape sequences are interpreted properly on Windows
+	enableVirtualTerminalProcessing()
+
 	if err != nil {
 		fmt.Println(AnsiError + "Failed to decrypt \"" + targetLocation + "\" - ensure it is a valid GPG-encrypted file and that you entered your passphrase correctly" + AnsiReset)
 		os.Exit(1)
 	}
 	outputSlice := strings.Split(string(output), "\n")
+
 	return outputSlice
 }