package server

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"time"

	log "github.com/sirupsen/logrus"

	nbpeer "github.com/netbirdio/netbird/management/server/peer"
	"github.com/netbirdio/netbird/management/server/telemetry"
)

type Store interface {
	GetAllAccounts() []*Account
	GetAccount(accountID string) (*Account, error)
	DeleteAccount(account *Account) error
	GetAccountByUser(userID string) (*Account, error)
	GetAccountByPeerPubKey(peerKey string) (*Account, error)
	GetAccountIDByPeerPubKey(peerKey string) (string, error)
	GetAccountByPeerID(peerID string) (*Account, error)
	GetAccountBySetupKey(setupKey string) (*Account, error) // todo use key hash later
	GetAccountByPrivateDomain(domain string) (*Account, error)
	GetTokenIDByHashedToken(secret string) (string, error)
	GetUserByTokenID(tokenID string) (*User, error)
	SaveAccount(account *Account) error
	DeleteHashedPAT2TokenIDIndex(hashedToken string) error
	DeleteTokenID2UserIDIndex(tokenID string) error
	GetInstallationID() string
	SaveInstallationID(ID string) error
	// AcquireAccountWriteLock should attempt to acquire account lock for write purposes and return a function that releases the lock
	AcquireAccountWriteLock(accountID string) func()
	// AcquireAccountReadLock should attempt to acquire account lock for read purposes and return a function that releases the lock
	AcquireAccountReadLock(accountID string) func()
	// AcquireGlobalLock should attempt to acquire a global lock and return a function that releases the lock
	AcquireGlobalLock() func()
	SavePeerStatus(accountID, peerID string, status nbpeer.PeerStatus) error
	SavePeerLocation(accountID string, peer *nbpeer.Peer) error
	SaveUserLastLogin(accountID, userID string, lastLogin time.Time) error
	// Close should close the store persisting all unsaved data.
	Close() error
	// GetStoreEngine should return StoreEngine of the current store implementation.
	// This is also a method of metrics.DataSource interface.
	GetStoreEngine() StoreEngine
}

type StoreEngine string

const (
	FileStoreEngine   StoreEngine = "jsonfile"
	SqliteStoreEngine StoreEngine = "sqlite"
)

func getStoreEngineFromEnv() StoreEngine {
	// NETBIRD_STORE_ENGINE supposed to be used in tests. Otherwise, rely on the config file.
	kind, ok := os.LookupEnv("NETBIRD_STORE_ENGINE")
	if !ok {
		return ""
	}

	value := StoreEngine(strings.ToLower(kind))

	if value == FileStoreEngine || value == SqliteStoreEngine {
		return value
	}

	return SqliteStoreEngine
}

func getStoreEngineFromDatadir(dataDir string) StoreEngine {
	storeFile := filepath.Join(dataDir, storeFileName)
	if _, err := os.Stat(storeFile); err != nil {
		// json file not found then use sqlite as default
		return SqliteStoreEngine
	}
	return FileStoreEngine
}

func NewStore(kind StoreEngine, dataDir string, metrics telemetry.AppMetrics) (Store, error) {
	if kind == "" {
		// if store engine is not set in the config we first try to evaluate NETBIRD_STORE_ENGINE
		kind = getStoreEngineFromEnv()
		if kind == "" {
			// NETBIRD_STORE_ENGINE is not set we evaluate default based on dataDir
			kind = getStoreEngineFromDatadir(dataDir)
		}
	}
	switch kind {
	case FileStoreEngine:
		log.Info("using JSON file store engine")
		return NewFileStore(dataDir, metrics)
	case SqliteStoreEngine:
		log.Info("using SQLite store engine")
		return NewSqliteStore(dataDir, metrics)
	default:
		return nil, fmt.Errorf("unsupported kind of store %s", kind)
	}
}

// NewStoreFromJson is only used in tests
func NewStoreFromJson(dataDir string, metrics telemetry.AppMetrics) (Store, error) {
	fstore, err := NewFileStore(dataDir, nil)
	if err != nil {
		return nil, err
	}

	// if store engine is not set in the config we first try to evaluate NETBIRD_STORE_ENGINE
	kind := getStoreEngineFromEnv()
	if kind == "" {
		// NETBIRD_STORE_ENGINE is not set we evaluate default based on dataDir
		kind = getStoreEngineFromDatadir(dataDir)
	}

	switch kind {
	case FileStoreEngine:
		return fstore, nil
	case SqliteStoreEngine:
		return NewSqliteStoreFromFileStore(fstore, dataDir, metrics)
	default:
		return NewSqliteStoreFromFileStore(fstore, dataDir, metrics)
	}
}