package cat

import (
	"log"
	"os"
	"path/filepath"
)

// debugLog writes CAT debug events to %APPDATA%/HamLog/cat.log so users can
// diagnose mode/freq mismatches without rebuilding with -windowsconsole.
//
// Initialised lazily on first use. Falls back to the standard library
// default logger (stderr, usually invisible in a Wails GUI build) if the
// log file can't be opened.
var debugLog = openDebugLog()

func openDebugLog() *log.Logger {
	base, err := os.UserConfigDir()
	if err != nil {
		return log.Default()
	}
	dir := filepath.Join(base, "HamLog")
	if err := os.MkdirAll(dir, 0o755); err != nil {
		return log.Default()
	}
	f, err := os.OpenFile(filepath.Join(dir, "cat.log"),
		os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
	if err != nil {
		return log.Default()
	}
	return log.New(f, "", log.LstdFlags|log.Lmicroseconds)
}

// DebugLogPath returns the path the cat.log file would be opened at, for
// surfacing in the UI / docs.
func DebugLogPath() string {
	base, err := os.UserConfigDir()
	if err != nil {
		return ""
	}
	return filepath.Join(base, "HamLog", "cat.log")
}