package main

import (
	"fmt"
	"os"

	"github.com/spf13/cobra"

	"git.wxccs.org/iceking2nd/winauth-go/internal/config"
	"git.wxccs.org/iceking2nd/winauth-go/internal/global"
	"git.wxccs.org/iceking2nd/winauth-go/internal/i18n"
	"git.wxccs.org/iceking2nd/winauth-go/internal/logging"
	"git.wxccs.org/iceking2nd/winauth-go/internal/ui"
	"git.wxccs.org/iceking2nd/winauth-go/internal/version"
	"git.wxccs.org/iceking2nd/winauth-go/internal/win32"
)

const (
	// singleInstanceMutex is the name used by AcquireInstanceLock. The
	// "Global\" prefix would make the lock cross-session; without it
	// each Windows user sees their own copy, which is what we want
	// (config.yaml is per-user anyway).
	singleInstanceMutex = "winauth-go-single-instance-mutex"
	// windowTitle is what AcquireInstanceLock's duplicate path tries to
	// foreground. Must stay in sync with ui.Run's app.Title option.
	windowTitle = "WinAuth"
)

func main() {
	var (
		console    bool
		logLevel   string
		logFile    string
		configPath string
	)

	root := &cobra.Command{
		Use:   "winauth-go",
		Short: "WinAuth (Go port) — TOTP/HOTP authenticator",
		RunE: func(cmd *cobra.Command, args []string) error {
			if console {
				logging.AttachConsole()
			}

			closer, err := logging.Init(logging.Options{
				Level:   logLevel,
				File:    logFile,
				Console: console,
			})
			if err != nil {
				return err
			}
			if closer != nil {
				defer func() { _ = closer.Close() }()
			}

			const fn = "cmd.winauth.main"
			global.Log.WithField("func", fn).
				WithField("version", version.String()).Info("winauth-go starting")

			release, alreadyRunning, err := win32.AcquireInstanceLock(singleInstanceMutex)
			if err != nil {
				global.Log.WithField("func", fn).WithError(err).Warn("instance lock failed; continuing without it")
			}
			if alreadyRunning {
				global.Log.WithField("func", fn).Info("another instance already running; activating it")
				if err := win32.ActivateOtherInstance(windowTitle); err != nil {
					global.Log.WithField("func", fn).WithError(err).Warn("could not activate existing window")
				}
				return nil
			}
			if release != nil {
				defer release()
			}

			// Peek the config (without password) to recover the user's
			// last language choice before initialising i18n. Encrypted
			// configs still expose Language at the YAML top level so we
			// can localise the password prompt itself.
			lang := preferredLanguage(configPath)
			if err := i18n.Init(lang); err != nil {
				global.Log.WithField("func", fn).WithError(err).Warn("i18n init failed; falling back to keys")
			}

			return ui.Run(configPath)
		},
	}

	root.Flags().BoolVar(&console, "console", false, "Show console window (Windows GUI builds)")
	root.Flags().StringVar(&logLevel, "log-level", "info",
		"Log level: panic|fatal|error|warn|info|debug|trace (or 0..6)")
	root.Flags().StringVar(&logFile, "log-file", "",
		"If set, also write logs to this file in addition to the console")
	root.Flags().StringVar(&configPath, "config", "",
		"Path to the YAML config file (default: %APPDATA%\\winauth-go\\config.yaml or $XDG_CONFIG_HOME/winauth-go/config.yaml)")

	if err := root.Execute(); err != nil {
		fmt.Fprintln(os.Stderr, "error:", err)
		os.Exit(1)
	}
}

// preferredLanguage reads the user's saved language tag out of the YAML
// config without requiring a passphrase. We resolve the default config
// path when configPath is blank and silently return "" on any failure;
// callers fall back to the i18n default in that case. Encrypted configs
// still expose the top-level Language field so this works for them too.
func preferredLanguage(configPath string) string {
	if configPath == "" {
		configPath = config.DefaultPath()
	}
	cfg, _ := config.LoadYAML(configPath, nil)
	if cfg == nil {
		return ""
	}
	return cfg.Language
}