package s5

import (
	"context"
	"crypto/ed25519"
	"errors"
	"fmt"
	"time"

	"git.lumeweb.com/LumeWeb/portal/metadata"

	"git.lumeweb.com/LumeWeb/portal/storage"

	s5config "git.lumeweb.com/LumeWeb/libs5-go/config"
	s5ed "git.lumeweb.com/LumeWeb/libs5-go/ed25519"
	"git.lumeweb.com/LumeWeb/libs5-go/encoding"
	s5fx "git.lumeweb.com/LumeWeb/libs5-go/fx"
	s5node "git.lumeweb.com/LumeWeb/libs5-go/node"
	s5storage "git.lumeweb.com/LumeWeb/libs5-go/storage"
	"git.lumeweb.com/LumeWeb/libs5-go/types"
	"git.lumeweb.com/LumeWeb/portal/protocols/registry"
	"github.com/spf13/viper"
	bolt "go.etcd.io/bbolt"
	"go.uber.org/fx"
	"go.uber.org/zap"
)

var (
	_ s5storage.ProviderStore = (*S5ProviderStore)(nil)
	_ registry.Protocol       = (*S5Protocol)(nil)
)

type S5Protocol struct {
	config     *viper.Viper
	logger     *zap.Logger
	storage    storage.StorageService
	identity   ed25519.PrivateKey
	node       *s5node.Node
	tusHandler *TusHandler
}

type S5ProtocolParams struct {
	fx.In
	Config        *viper.Viper
	Logger        *zap.Logger
	Storage       storage.StorageService
	Identity      ed25519.PrivateKey
	ProviderStore *S5ProviderStore
	TusHandler    *TusHandler
}

type S5ProtocolResult struct {
	fx.Out
	Protocol        registry.Protocol `group:"protocol"`
	S5Protocol      *S5Protocol
	S5NodeConfig    *s5config.NodeConfig
	Db              *bolt.DB
	StorageProtocol storage.StorageProtocol
}

type S5ProviderStoreParams struct {
	fx.In
	Config   *viper.Viper
	Metadata metadata.MetadataService
	Logger   *zap.Logger
	Tus      *TusHandler
}

var ProtocolModule = fx.Module("s5_api",
	fx.Provide(NewS5Protocol),
	fx.Provide(NewTusHandler),
	fx.Provide(NewS5ProviderStore),
	fx.Replace(func(cfg *s5config.NodeConfig) *zap.Logger {
		return cfg.Logger
	}),
	s5fx.Module,
)

func NewS5Protocol(
	params S5ProtocolParams,
) (S5ProtocolResult, error) {
	proto := &S5Protocol{
		config:     params.Config,
		logger:     params.Logger,
		storage:    params.Storage,
		identity:   params.Identity,
		tusHandler: params.TusHandler,
	}

	cfg, err := ConfigureS5Protocol(params)
	if err != nil {
		return S5ProtocolResult{}, err
	}

	return S5ProtocolResult{
		Protocol:        proto,
		S5Protocol:      proto,
		S5NodeConfig:    cfg,
		Db:              cfg.DB,
		StorageProtocol: GetStorageProtocol(proto),
	}, nil
}

func ConfigureS5Protocol(params S5ProtocolParams) (*s5config.NodeConfig, error) {
	cfg := &s5config.NodeConfig{
		P2P: s5config.P2PConfig{
			Network: "",
			Peers:   s5config.PeersConfig{Initial: []string{}},
		},
		KeyPair: s5ed.New(params.Identity),
		DB:      nil,
		Logger:  params.Logger.Named("s5"),
		HTTP:    s5config.HTTPConfig{},
	}

	pconfig := params.Config.Sub("protocol.s5")

	if pconfig == nil {
		params.Logger.Fatal("Missing protocol.s5 Config")
	}

	err := pconfig.Unmarshal(cfg)
	if err != nil {
		return nil, err
	}

	cfg.HTTP.API.Domain = fmt.Sprintf("s5.%s", params.Config.GetString("core.domain"))

	if params.Config.IsSet("core.externalPort") {
		cfg.HTTP.API.Port = params.Config.GetUint("core.externalPort")
	} else {
		cfg.HTTP.API.Port = params.Config.GetUint("core.port")
	}

	dbPath := pconfig.GetString("dbPath")

	if dbPath == "" {
		params.Logger.Fatal("protocol.s5.dbPath is required")
	}

	_, p, err := ed25519.GenerateKey(nil)
	if err != nil {
		params.Logger.Fatal("Failed to generate key", zap.Error(err))
	}

	cfg.KeyPair = s5ed.New(p)

	db, err := bolt.Open(dbPath, 0600, nil)
	if err != nil {
		params.Logger.Fatal("Failed to open db", zap.Error(err))
	}

	cfg.DB = db

	return cfg, nil
}

func NewS5ProviderStore(params S5ProviderStoreParams) *S5ProviderStore {
	return &S5ProviderStore{
		config:   params.Config,
		logger:   params.Logger,
		tus:      params.Tus,
		metadata: params.Metadata,
	}
}

func (s *S5Protocol) Init(args ...any) error {
	if node, ok := args[0].(*s5node.Node); !ok {
		s.logger.Fatal("Node is not a s5 node")
	} else {
		s.node = node
	}

	if store, ok := args[1].(*S5ProviderStore); !ok {
		s.logger.Fatal("Store is not a s5 store")
	} else {
		s.node.Services().Storage().SetProviderStore(store)
	}

	err := s.node.Init()
	if err != nil {
		return err
	}

	err = s.tusHandler.Init()
	if err != nil {
		return err
	}

	return nil
}
func (s *S5Protocol) Start(ctx context.Context) error {
	err := s.node.Start()
	if err != nil {
		return err
	}

	identity, err := s.node.NodeId().ToString()

	if err != nil {
		return err
	}

	s.logger.Info("S5 protocol started", zap.String("identity", identity), zap.String("network", s.node.NetworkId()), zap.String("domain", s.node.Config().HTTP.API.Domain))

	return nil
}

func (s *S5Protocol) Name() string {
	return "s5"
}

func (s *S5Protocol) Node() *s5node.Node {
	return s.node
}

func (s *S5Protocol) Stop(ctx context.Context) error {
	return nil
}

type S5ProviderStore struct {
	config   *viper.Viper
	logger   *zap.Logger
	tus      *TusHandler
	metadata metadata.MetadataService
}

func (s S5ProviderStore) CanProvide(hash *encoding.Multihash, kind []types.StorageLocationType) bool {
	ctx := context.Background()
	for _, t := range kind {
		switch t {
		case types.StorageLocationTypeArchive, types.StorageLocationTypeFile, types.StorageLocationTypeFull:
			rawHash := hash.HashBytes()

			if exists, upload := s.tus.UploadExists(ctx, rawHash); exists {
				if upload.Completed {
					return true
				}

			}
			if _, err := s.metadata.GetUpload(ctx, rawHash); errors.Is(err, metadata.ErrNotFound) {
				return true
			}
		}
	}
	return false
}

func (s S5ProviderStore) Provide(hash *encoding.Multihash, kind []types.StorageLocationType) (s5storage.StorageLocation, error) {
	for _, t := range kind {
		if !s.CanProvide(hash, []types.StorageLocationType{t}) {
			continue
		}

		switch t {
		case types.StorageLocationTypeArchive:
			return s5storage.NewStorageLocation(int(types.StorageLocationTypeArchive), []string{}, calculateExpiry(24*time.Hour)), nil
		case types.StorageLocationTypeFile, types.StorageLocationTypeFull:
			return s5storage.NewStorageLocation(int(types.StorageLocationTypeFull), []string{generateDownloadUrl(hash, s.config, s.logger), generateProofUrl(hash, s.config, s.logger)}, calculateExpiry(24*time.Hour)), nil
		}
	}

	hashStr, err := hash.ToString()
	if err != nil {
		return nil, err
	}

	return nil, fmt.Errorf("could not provide hash %s for types %v", hashStr, kind)
}
func calculateExpiry(duration time.Duration) int64 {
	return time.Now().Add(duration).Unix()
}

func generateDownloadUrl(hash *encoding.Multihash, config *viper.Viper, logger *zap.Logger) string {
	domain := config.GetString("core.domain")

	hashStr, err := hash.ToBase64Url()
	if err != nil {
		logger.Error("error encoding hash", zap.Error(err))
	}

	return fmt.Sprintf("https://s5.%s/s5/download/%s", domain, hashStr)
}

func generateProofUrl(hash *encoding.Multihash, config *viper.Viper, logger *zap.Logger) string {
	domain := config.GetString("core.domain")

	hashStr, err := hash.ToBase64Url()
	if err != nil {
		logger.Error("error encoding hash", zap.Error(err))
	}

	return fmt.Sprintf("https://s5.%s/s5/download/%s.obao", domain, hashStr)
}