package settings

import (
	"encoding/json"
	"io"
	"io/fs"
	"path/filepath"
	"strings"

	"server/log"
)

type BTSets struct {
	// Cache
	CacheSize       int64 // in byte, def 96 MB
	ReaderReadAHead int   // in percent, 5%-100%, [...S__X__E...] [S-E] not clean
	PreloadCache    int   // in percent

	// Disk
	UseDisk           bool
	TorrentsSavePath  string
	RemoveCacheOnDrop bool

	// Torrent
	ForceEncrypt             bool
	RetrackersMode           int  // 0 - don`t add, 1 - add retrackers (def), 2 - remove retrackers 3 - replace retrackers
	TorrentDisconnectTimeout int  // in seconds
	EnableDebug              bool // print logs

	// BT Config
	AcceptPeerCon     bool `default:"true"`
	AnnTorrentsToDht  bool `default:"true"`
	EnableIPv6        bool
	DisableTCP        bool
	DisableUTP        bool
	DisableUPNP       bool
	DisableDHT        bool
	DisablePEX        bool
	DisableUpload     bool
	DownloadRateLimit int // in kb, 0 - inf
	UploadRateLimit   int // in kb, 0 - inf
	ConnectionsLimit  int
	//DhtConnectionLimit int // 0 - inf
	PeersListenPort int
	//Strategy           int // 0 - RequestStrategyDuplicateRequestTimeout, 1 - RequestStrategyFuzzing, 2 - RequestStrategyFastest
}

func (v *BTSets) String() string {
	buf, _ := json.Marshal(v)
	return string(buf)
}

var (
	BTsets *BTSets
)

func SetBTSets(sets *BTSets) {
	if ReadOnly {
		return
	}

	if sets.ReaderReadAHead < 5 {
		sets.ReaderReadAHead = 5
	}
	if sets.ReaderReadAHead > 100 {
		sets.ReaderReadAHead = 100
	}

	if sets.PreloadCache < 0 {
		sets.PreloadCache = 0
	}
	if sets.PreloadCache > 100 {
		sets.PreloadCache = 100
	}

	if sets.TorrentsSavePath == "" {
		sets.UseDisk = false
	} else if sets.UseDisk {
		BTsets = sets

		go filepath.WalkDir(sets.TorrentsSavePath, func(path string, d fs.DirEntry, err error) error {
			if err != nil {
				return err
			}
			if d.IsDir() && strings.ToLower(d.Name()) == ".tsc" {
				BTsets.TorrentsSavePath = path
				log.TLogln("Find directory \"" + BTsets.TorrentsSavePath + "\", use as cache dir")
				return io.EOF
			}
			if d.IsDir() && strings.HasPrefix(d.Name(), ".") {
				return filepath.SkipDir
			}
			return nil
		})
	}

	BTsets = sets
	buf, err := json.Marshal(BTsets)
	if err != nil {
		log.TLogln("Error marshal btsets", err)
		return
	}
	tdb.Set("Settings", "BitTorr", buf)
}

func loadBTSets() {
	buf := tdb.Get("Settings", "BitTorr")
	if len(buf) > 0 {
		err := json.Unmarshal(buf, &BTsets)
		if err == nil {
			if BTsets.ReaderReadAHead < 5 {
				BTsets.ReaderReadAHead = 5
			}
			return
		}
		log.TLogln("Error unmarshal btsets", err)
	}

	SetDefault()
}

func SetDefault() {
	sets := new(BTSets)
	sets.AcceptPeerCon = true
	sets.AnnTorrentsToDht = true
	sets.EnableDebug = false
	sets.DisableUTP = true
	sets.CacheSize = 96 * 1024 * 1024 // 96 MB
	sets.PreloadCache = 0
	sets.ConnectionsLimit = 23
	//sets.DhtConnectionLimit = 500
	sets.RetrackersMode = 1
	sets.TorrentDisconnectTimeout = 30
	sets.ReaderReadAHead = 95 // 95% preload
	BTsets = sets
}