package main

import (
	"context"
	"fmt"
	"os"
	"strings"

	"github.com/spf13/cobra"

	"github.com/fatedier/frp/pkg/config"
	v1 "github.com/fatedier/frp/pkg/config/v1"
	"github.com/fatedier/frp/pkg/config/v1/validation"
	"github.com/fatedier/frp/pkg/db"
	"github.com/fatedier/frp/pkg/policy/security"
	"github.com/fatedier/frp/pkg/util/log"
	"github.com/fatedier/frp/pkg/util/version"
	"github.com/fatedier/frp/server"
)

var (
	cfgFile          string
	showVersion      bool
	strictConfigMode bool
	allowUnsafe      []string

	serverCfg v1.ServerConfig
)

func init() {
	rootCmd.PersistentFlags().StringVarP(&cfgFile, "config", "c", "", "config file of frps")
	rootCmd.PersistentFlags().BoolVarP(&showVersion, "version", "v", false, "version of frps")
	rootCmd.PersistentFlags().BoolVarP(&strictConfigMode, "strict_config", "", true, "strict config parsing mode, unknown fields will cause errors")
	rootCmd.PersistentFlags().StringSliceVarP(&allowUnsafe, "allow-unsafe", "", []string{},
		fmt.Sprintf("allowed unsafe features, one or more of: %s", strings.Join(security.ServerUnsafeFeatures, ", ")))

	config.RegisterServerConfigFlags(rootCmd, &serverCfg)
}

var rootCmd = &cobra.Command{
	Use:   "frps",
	Short: "frps is the server of frp (https://github.com/fatedier/frp)",
	RunE: func(cmd *cobra.Command, args []string) error {
		if showVersion {
			fmt.Println(version.Full())
			return nil
		}

		if err := db.Init("sqlite", "admin.db"); err != nil {
			fmt.Printf("failed to initialize admin database: %v\n", err)
			os.Exit(1)
		}
		defer db.Close()

		var (
			svrCfg         *v1.ServerConfig
			isLegacyFormat bool
			err            error
		)
		if cfgFile != "" {
			svrCfg, isLegacyFormat, err = config.LoadServerConfig(cfgFile, strictConfigMode)
			if err != nil {
				fmt.Println(err)
				os.Exit(1)
			}
			if isLegacyFormat {
				fmt.Printf("WARNING: ini format is deprecated, please use yaml/json/toml instead!\n")
			}
		} else {
			svrCfg, err = loadConfigFromDB()
			if err != nil {
				fmt.Printf("failed to load server config: %v\n", err)
				os.Exit(1)
			}
		}

		unsafeFeatures := security.NewUnsafeFeatures(allowUnsafe)
		validator := validation.NewConfigValidator(unsafeFeatures)
		warning, err := validator.ValidateServerConfig(svrCfg)
		if warning != nil {
			fmt.Printf("WARNING: %v\n", warning)
		}
		if err != nil {
			fmt.Println(err)
			os.Exit(1)
		}

		if err := runServer(svrCfg); err != nil {
			fmt.Println(err)
			os.Exit(1)
		}
		return nil
	},
}

func Execute() {
	rootCmd.SetGlobalNormalizationFunc(config.WordSepNormalizeFunc)
	if err := rootCmd.Execute(); err != nil {
		os.Exit(1)
	}
}

func loadConfigFromDB() (*v1.ServerConfig, error) {
	hasConfig, err := db.HasServerConfig()
	if err != nil {
		return nil, fmt.Errorf("failed to check server config in db: %w", err)
	}

	if hasConfig {
		cfg, err := db.LoadServerConfig()
		if err != nil {
			return nil, fmt.Errorf("failed to load server config from db: %w", err)
		}
		if err := cfg.Complete(); err != nil {
			return nil, fmt.Errorf("failed to complete server config: %w", err)
		}
		log.Infof("frps uses database configuration")
		return cfg, nil
	}

	cfg := db.DefaultServerConfig()
	if err := cfg.Complete(); err != nil {
		return nil, fmt.Errorf("failed to complete server config: %w", err)
	}
	if err := db.SaveServerConfig(cfg); err != nil {
		log.Warnf("failed to save default config to db: %v", err)
	}
	log.Infof("frps started with default configuration (first run)")
	return cfg, nil
}

func runServer(cfg *v1.ServerConfig) (err error) {
	log.InitLogger(cfg.Log.To, cfg.Log.Level, int(cfg.Log.MaxDays), cfg.Log.DisablePrintColor)

	if cfgFile != "" {
		log.Infof("frps uses config file: %s", cfgFile)
	} else {
		log.Infof("frps uses database configuration")
	}

	svr, err := server.NewService(cfg)
	if err != nil {
		return err
	}
	log.Infof("frps started successfully")
	svr.Run(context.Background())
	return
}