package cli

import (
	"io"
	"os"
	"path/filepath"
	"sync/atomic"
	"time"

	"github.com/kardianos/service"
	"github.com/rs/zerolog"

	"github.com/Control-D-Inc/ctrld"
)

var (
	configPath        string
	configBase64      string
	daemon            bool
	listenAddress     string
	primaryUpstream   string
	secondaryUpstream string
	domains           []string
	logPath           string
	homedir           string
	cacheSize         int
	cfg               ctrld.Config
	verbose           int
	silent            bool
	cdUID             string
	cdOrg             string
	cdDev             bool
	iface             string
	ifaceStartStop    string

	mainLog       atomic.Pointer[zerolog.Logger]
	consoleWriter zerolog.ConsoleWriter
	noConfigStart bool
)

func init() {
	l := zerolog.New(io.Discard)
	mainLog.Store(&l)
}

func Main() {
	ctrld.InitConfig(v, "ctrld")
	initCLI()
	if err := rootCmd.Execute(); err != nil {
		mainLog.Load().Error().Msg(err.Error())
		os.Exit(1)
	}
}

func normalizeLogFilePath(logFilePath string) string {
	if logFilePath == "" || filepath.IsAbs(logFilePath) || service.Interactive() {
		return logFilePath
	}
	if homedir != "" {
		return filepath.Join(homedir, logFilePath)
	}
	dir, _ := userHomeDir()
	if dir == "" {
		return logFilePath
	}
	return filepath.Join(dir, logFilePath)
}

// initConsoleLogging initializes console logging, then storing to mainLog.
func initConsoleLogging() {
	consoleWriter = zerolog.NewConsoleWriter(func(w *zerolog.ConsoleWriter) {
		w.TimeFormat = time.StampMilli
	})
	multi := zerolog.MultiLevelWriter(consoleWriter)
	l := mainLog.Load().Output(multi).With().Timestamp().Logger()
	mainLog.Store(&l)
	switch {
	case silent:
		zerolog.SetGlobalLevel(zerolog.NoLevel)
	case verbose == 1:
		zerolog.SetGlobalLevel(zerolog.InfoLevel)
	case verbose > 1:
		zerolog.SetGlobalLevel(zerolog.DebugLevel)
	default:
		zerolog.SetGlobalLevel(zerolog.NoticeLevel)
	}
}

// initLogging initializes global logging setup.
func initLogging() {
	initLoggingWithBackup(true)
}

// initLoggingWithBackup initializes log setup base on current config.
// If doBackup is true, backup old log file with ".1" suffix.
//
// This is only used in runCmd for special handling in case of logging config
// change in cd mode. Without special reason, the caller should use initLogging
// wrapper instead of calling this function directly.
func initLoggingWithBackup(doBackup bool) {
	writers := []io.Writer{io.Discard}
	if logFilePath := normalizeLogFilePath(cfg.Service.LogPath); logFilePath != "" {
		// Create parent directory if necessary.
		if err := os.MkdirAll(filepath.Dir(logFilePath), 0750); err != nil {
			mainLog.Load().Error().Msgf("failed to create log path: %v", err)
			os.Exit(1)
		}

		// Default open log file in append mode.
		flags := os.O_CREATE | os.O_RDWR | os.O_APPEND
		if doBackup {
			// Backup old log file with .1 suffix.
			if err := os.Rename(logFilePath, logFilePath+".1"); err != nil && !os.IsNotExist(err) {
				mainLog.Load().Error().Msgf("could not backup old log file: %v", err)
			} else {
				// Backup was created, set flags for truncating old log file.
				flags = os.O_CREATE | os.O_RDWR
			}
		}
		logFile, err := os.OpenFile(logFilePath, flags, os.FileMode(0o600))
		if err != nil {
			mainLog.Load().Error().Msgf("failed to create log file: %v", err)
			os.Exit(1)
		}
		writers = append(writers, logFile)
	}
	writers = append(writers, consoleWriter)
	multi := zerolog.MultiLevelWriter(writers...)
	l := mainLog.Load().Output(multi).With().Timestamp().Logger()
	mainLog.Store(&l)
	// TODO: find a better way.
	ctrld.ProxyLogger.Store(&l)

	zerolog.SetGlobalLevel(zerolog.NoticeLevel)
	logLevel := cfg.Service.LogLevel
	switch {
	case silent:
		zerolog.SetGlobalLevel(zerolog.NoLevel)
		return
	case verbose == 1:
		logLevel = "info"
	case verbose > 1:
		logLevel = "debug"
	}
	if logLevel == "" {
		return
	}
	level, err := zerolog.ParseLevel(logLevel)
	if err != nil {
		mainLog.Load().Warn().Err(err).Msg("could not set log level")
		return
	}
	zerolog.SetGlobalLevel(level)
}

func initCache() {
	if !cfg.Service.CacheEnable {
		return
	}
	if cfg.Service.CacheSize == 0 {
		cfg.Service.CacheSize = 4096
	}
}