// Copyright (C) 2017 Marius Schellenberger

package main

import (
	"errors"
	"git.giftfish.de/ston1th/godrop"
	"github.com/urfave/cli"
	logger "log"
	"net"
	"os"
	"os/signal"
	"syscall"
	"time"
)

const (
	blevePath = "bleve"

	defDataDir = "/var/lib/gowiki"
	defListen  = "127.0.0.1:8090"
	defLogFile = "gowiki.log"

	defRunUser  = "wiki"
	defRunGroup = "wiki"
)

func server(conf serverConfig) (err error) {
	dropCfg := godrop.Config{
		User:       conf.User,
		Group:      conf.Group,
		Foreground: conf.Foreground,
	}
	err = godrop.Drop(dropCfg, func() (net.Listener, error) {
		return net.Listen("tcp", conf.ListenAddr)
	})
	if err != nil {
		return
	}
	if err = os.Chdir(conf.DataDir); err != nil {
		return
	}

	newLogger(conf.LogFile)

	l, err := godrop.GetListener()
	if err != nil {
		return
	}

	srv := NewHTTPServer(l, conf.Version, conf.SecureCookie)
	err = srv.Start()
	if err != nil {
		return
	}
	log.Println("gowiki started")
	sigs := make(chan os.Signal)
	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
	sig := <-sigs
	log.Println("caught " + sig.String())
	go func() {
		time.Sleep(time.Second * 20)
		log.Fatal(errors.New("stop timed out: killing"))
	}()
	err = srv.Stop()
	if err != nil {
		log.Println(err)
	}
	log.Println("gowiki stopped")
	return
}

var (
	verbose bool
	conf    serverConfig
)

func run(app *cli.App) {
	app.Commands = []cli.Command{
		{
			Name:  "server",
			Usage: "start gowiki server",
			Flags: defaultFlags(serverFlags()),
			Action: func(c *cli.Context) error {
				conf.Version = app.Version
				if err := server(conf); err != nil {
					logger.Fatal("server: ", err)
				}
				return nil
			},
		},
		{
			Name:  "dump",
			Usage: "create a json dump of all articles in the data directory (dump is written to stdout) gowiki needs to be stopped",
			Flags: defaultFlags(dumpRestoreFlags()),
			Action: func(c *cli.Context) error {
				if err := os.Chdir(conf.DataDir); err != nil {
					logger.Fatal("dump: ", err)
				}
				if err := dump(blevePath, verbose); err != nil {
					logger.Fatal("dump: ", err)
				}
				return nil
			},
		},
		{
			Name:  "restore",
			Usage: "restore a json dump to the data directory (dump is read from stdin) gowiki needs to be stopped",
			Flags: defaultFlags(dumpRestoreFlags()),
			Action: func(c *cli.Context) error {
				if err := os.Chdir(conf.DataDir); err != nil {
					logger.Fatal("restore: ", err)
				}
				if err := restore(blevePath, verbose); err != nil {
					logger.Fatal("restore: ", err)
				}
				return nil
			},
		},
	}
	app.Run(os.Args)
}

type serverConfig struct {
	DataDir      string
	User         string
	Group        string
	ListenAddr   string
	LogFile      string
	Version      string
	Foreground   bool
	SecureCookie bool
}

func serverFlags() []cli.Flag {
	return []cli.Flag{
		cli.StringFlag{
			Name:        "user, u",
			Value:       defRunUser,
			Usage:       "drop privileges to user",
			Destination: &conf.User,
		},
		cli.StringFlag{
			Name:        "group, g",
			Value:       defRunGroup,
			Usage:       "drop privileges to group",
			Destination: &conf.Group,
		},
		cli.StringFlag{
			Name:        "listen, l",
			Value:       defListen,
			Usage:       "listening <address>:<port>",
			Destination: &conf.ListenAddr,
		},
		cli.StringFlag{
			Name:        "log",
			Value:       defLogFile,
			Usage:       "log file (leave empty for stdout, this only works in combination with -f)",
			Destination: &conf.LogFile,
		},
		cli.BoolFlag{
			Name:        "foreground, f",
			Usage:       "do not fork into the background",
			Destination: &conf.Foreground,
		},
		cli.BoolFlag{
			Name:        "secure, s",
			Usage:       "enable secure cookie",
			Destination: &conf.SecureCookie,
		},
	}
}

func dumpRestoreFlags() []cli.Flag {
	return []cli.Flag{
		cli.BoolFlag{
			Name:        "verbose, v",
			Usage:       "enable verbose mode",
			Destination: &verbose,
		},
	}
}

func defaultFlags(f []cli.Flag) []cli.Flag {
	return append([]cli.Flag{
		cli.StringFlag{
			Name:        "data, d",
			Value:       defDataDir,
			Usage:       "data directory",
			Destination: &conf.DataDir,
		},
	}, f...)
}