package main

import (
	"context"
	"crypto/ecdsa"
	"net"
	"os"
	"path"
	"strconv"
	"strings"
	"sync"
	"time"

	"github.com/nspcc-dev/neo-go/pkg/util"
	"github.com/nspcc-dev/neofs-api-go/pkg"
	"github.com/nspcc-dev/neofs-api-go/pkg/netmap"
	crypto "github.com/nspcc-dev/neofs-crypto"
	"github.com/nspcc-dev/neofs-node/misc"
	"github.com/nspcc-dev/neofs-node/pkg/core/container"
	netmapCore "github.com/nspcc-dev/neofs-node/pkg/core/netmap"
	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor"
	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/bucket"
	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/bucket/fsbucket"
	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/engine"
	meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase/v2"
	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard"
	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
	"github.com/nspcc-dev/neofs-node/pkg/morph/client/container/wrapper"
	nmwrapper "github.com/nspcc-dev/neofs-node/pkg/morph/client/netmap/wrapper"
	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
	"github.com/nspcc-dev/neofs-node/pkg/network"
	tokenStorage "github.com/nspcc-dev/neofs-node/pkg/services/session/storage"
	"github.com/nspcc-dev/neofs-node/pkg/services/util/response"
	"github.com/nspcc-dev/neofs-node/pkg/util/logger"
	"github.com/nspcc-dev/neofs-node/pkg/util/profiler"
	"github.com/panjf2000/ants/v2"
	"github.com/pkg/errors"
	"github.com/spf13/viper"
	"go.uber.org/zap"
	"google.golang.org/grpc"
)

const (
	// logger keys
	cfgLogLevel              = "logger.level"
	cfgLogFormat             = "logger.format"
	cfgLogTrace              = "logger.trace_level"
	cfgLogInitSampling       = "logger.sampling.initial"
	cfgLogThereafterSampling = "logger.sampling.thereafter"

	// pprof keys
	cfgProfilerEnable = "pprof.enabled"
	cfgProfilerAddr   = "pprof.address"
	cfgProfilerTTL    = "pprof.shutdown_ttl"

	// config keys for cfgNodeInfo
	cfgNodeKey             = "node.key"
	cfgBootstrapAddress    = "node.address"
	cfgNodeAttributePrefix = "node.attribute"

	// config keys for cfgGRPC
	cfgListenAddress  = "grpc.endpoint"
	cfgMaxMsgSize     = "grpc.maxmessagesize"
	cfgReflectService = "grpc.enable_reflect_service"

	// config keys for cfgMorph
	cfgMorphRPCAddress = "morph.endpoint"

	cfgMorphNotifyRPCAddress  = "morph.notification.endpoint"
	cfgMorphNotifyDialTimeout = "morph.notification.dial_timeout"

	// config keys for cfgAccounting
	cfgAccountingContract = "accounting.scripthash"
	cfgAccountingFee      = "accounting.fee"

	// config keys for cfgNetmap
	cfgNetmapContract = "netmap.scripthash"
	cfgNetmapFee      = "netmap.fee"

	// config keys for cfgContainer
	cfgContainerContract = "container.scripthash"
	cfgContainerFee      = "container.fee"

	cfgGCQueueSize = "gc.queuesize"
	cfgGCQueueTick = "gc.duration.sleep"
	cfgGCTimeout   = "gc.duration.timeout"

	cfgPolicerWorkScope   = "policer.work_scope"
	cfgPolicerExpRate     = "policer.expansion_rate"
	cfgPolicerHeadTimeout = "policer.head_timeout"
	cfgPolicerDialTimeout = "policer.dial_timeout"

	cfgReplicatorPutTimeout  = "replicator.put_timeout"
	cfgReplicatorDialTimeout = "replicator.dial_timeout"

	cfgReBootstrapEnabled  = "bootstrap.periodic.enabled"
	cfgReBootstrapInterval = "bootstrap.periodic.interval"

	cfgObjectPutPoolSize       = "pool.object.put.size"
	cfgObjectGetPoolSize       = "pool.object.get.size"
	cfgObjectHeadPoolSize      = "pool.object.head.size"
	cfgObjectSearchPoolSize    = "pool.object.search.size"
	cfgObjectRangePoolSize     = "pool.object.range.size"
	cfgObjectRangeHashPoolSize = "pool.object.rangehash.size"

	cfgObjectPutDialTimeout       = "object.put.dial_timeout"
	cfgObjectHeadDialTimeout      = "object.head.dial_timeout"
	cfgObjectRangeDialTimeout     = "object.range.dial_timeout"
	cfgObjectRangeHashDialTimeout = "object.rangehash.dial_timeout"
	cfgObjectSearchDialTimeout    = "object.search.dial_timeout"
)

const (
	cfgLocalStorageSection = "storage"
	cfgStorageShardSection = "shard"

	cfgShardUseWriteCache = "use_write_cache"

	cfgBlobStorSection      = "blobstor"
	cfgWriteCacheSection    = "writecache"
	cfgBlobStorCompress     = "compress"
	cfgBlobStorShallowDepth = "shallow_depth"
	cfgBlobStorTreePath     = "path"
	cfgBlobStorTreePerm     = "perm"
	cfgBlobStorSmallSzLimit = "small_size_limit"

	cfgBlobStorBlzSection = "blobovnicza"
	cfgBlzSize            = "size"
	cfgBlzShallowDepth    = "shallow_depth"
	cfgBlzShallowWidth    = "shallow_width"
	cfgBlzOpenedCacheSize = "opened_cache_size"

	cfgMetaBaseSection = "metabase"
	cfgMetaBasePath    = "path"
	cfgMetaBasePerm    = "perm"
)

const (
	addressSize = 72 // 32 bytes oid, 32 bytes cid, 8 bytes protobuf encoding
)

type cfg struct {
	ctx context.Context

	viper *viper.Viper

	log *zap.Logger

	wg *sync.WaitGroup

	key *ecdsa.PrivateKey

	apiVersion *pkg.Version

	cfgGRPC cfgGRPC

	cfgMorph cfgMorph

	cfgAccounting cfgAccounting

	cfgContainer cfgContainer

	cfgNetmap cfgNetmap

	privateTokenStore *tokenStorage.TokenStore

	cfgNodeInfo cfgNodeInfo

	localAddr *network.Address

	cfgObject cfgObject

	profiler profiler.Profiler

	workers []worker

	respSvc *response.Service
}

type cfgGRPC struct {
	listener net.Listener

	server *grpc.Server

	maxChunkSize uint64

	maxAddrAmount uint64

	enableReflectService bool
}

type cfgMorph struct {
	client *client.Client
}

type cfgAccounting struct {
	scriptHash util.Uint160

	fee util.Fixed8
}

type cfgContainer struct {
	scriptHash util.Uint160

	fee util.Fixed8
}

type cfgNetmap struct {
	scriptHash util.Uint160
	wrapper    *nmwrapper.Wrapper

	fee util.Fixed8

	parsers map[event.Type]event.Parser

	subscribers map[event.Type][]event.Handler

	state *networkState

	reBootstrapEnabled  bool
	reBootstrapInterval uint64 // in epochs
}

type BootstrapType uint32

type cfgNodeInfo struct {
	// values from config
	bootType   BootstrapType
	attributes []*netmap.NodeAttribute

	// values at runtime
	info *netmap.NodeInfo
}

type cfgObject struct {
	netMapStorage netmapCore.Source

	cnrStorage container.Source

	cnrClient *wrapper.Wrapper

	pool cfgObjectRoutines

	cfgLocalStorage cfgLocalStorage
}

type cfgLocalStorage struct {
	localStorage *engine.StorageEngine

	shardOpts [][]shard.Option
}

type cfgObjectRoutines struct {
	get, head, put, search, rng, rngHash *ants.Pool
}

const (
	_ BootstrapType = iota
	StorageNode
	RelayNode
)

func initCfg(path string) *cfg {
	viperCfg := initViper(path)

	key, err := crypto.LoadPrivateKey(viperCfg.GetString(cfgNodeKey))
	fatalOnErr(err)

	u160Accounting, err := util.Uint160DecodeStringLE(
		viperCfg.GetString(cfgAccountingContract))
	fatalOnErr(err)

	u160Netmap, err := util.Uint160DecodeStringLE(
		viperCfg.GetString(cfgNetmapContract))
	fatalOnErr(err)

	u160Container, err := util.Uint160DecodeStringLE(
		viperCfg.GetString(cfgContainerContract))
	fatalOnErr(err)

	log, err := logger.NewLogger(viperCfg)
	fatalOnErr(err)

	netAddr, err := network.AddressFromString(viperCfg.GetString(cfgBootstrapAddress))
	fatalOnErr(err)

	maxChunkSize := viperCfg.GetUint64(cfgMaxMsgSize) * 3 / 4 // 25% to meta, 75% to payload
	maxAddrAmount := maxChunkSize / addressSize               // each address is about 72 bytes

	state := newNetworkState()

	c := &cfg{
		ctx:        context.Background(),
		viper:      viperCfg,
		log:        log,
		wg:         new(sync.WaitGroup),
		key:        key,
		apiVersion: pkg.SDKVersion(),
		cfgAccounting: cfgAccounting{
			scriptHash: u160Accounting,
			fee:        util.Fixed8(viperCfg.GetInt(cfgAccountingFee)),
		},
		cfgContainer: cfgContainer{
			scriptHash: u160Container,
			fee:        util.Fixed8(viperCfg.GetInt(cfgContainerFee)),
		},
		cfgNetmap: cfgNetmap{
			scriptHash:          u160Netmap,
			fee:                 util.Fixed8(viperCfg.GetInt(cfgNetmapFee)),
			state:               state,
			reBootstrapInterval: viperCfg.GetUint64(cfgReBootstrapInterval),
			reBootstrapEnabled:  viperCfg.GetBool(cfgReBootstrapEnabled),
		},
		cfgNodeInfo: cfgNodeInfo{
			bootType:   StorageNode,
			attributes: parseAttributes(viperCfg),
		},
		cfgGRPC: cfgGRPC{
			maxChunkSize:         maxChunkSize,
			maxAddrAmount:        maxAddrAmount,
			enableReflectService: viperCfg.GetBool(cfgReflectService),
		},
		localAddr: netAddr,
		respSvc: response.NewService(
			response.WithNetworkState(state),
		),
		cfgObject: cfgObject{
			pool: initObjectPool(viperCfg),
		},
	}

	initLocalStorage(c)

	return c
}

func initViper(path string) *viper.Viper {
	v := viper.New()

	v.SetEnvPrefix(misc.Prefix)
	v.AutomaticEnv()
	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))

	v.SetDefault("app.name", misc.NodeName)
	v.SetDefault("app.version", misc.Version)

	defaultConfiguration(v)

	if path != "" {
		v.SetConfigFile(path)
		v.SetConfigType("yml")
		fatalOnErr(v.ReadInConfig())
	}

	return v
}

func defaultConfiguration(v *viper.Viper) {
	// fixme: all hardcoded private keys must be removed
	v.SetDefault(cfgNodeKey, "Kwk6k2eC3L3QuPvD8aiaNyoSXgQ2YL1bwS5CP1oKoA9waeAze97s")
	v.SetDefault(cfgBootstrapAddress, "") // address to bootstrap with

	v.SetDefault(cfgMorphRPCAddress, "http://morph_chain.localtest.nspcc.ru:30333/")
	v.SetDefault(cfgMorphNotifyRPCAddress, "ws://morph_chain:30333/ws")
	v.SetDefault(cfgMorphNotifyDialTimeout, 5*time.Second)
	v.SetDefault(cfgListenAddress, "127.0.0.1:50501") // listen address
	v.SetDefault(cfgMaxMsgSize, 4<<20)                // transport msg limit 4 MiB

	v.SetDefault(cfgAccountingContract, "1aeefe1d0dfade49740fff779c02cd4a0538ffb1")
	v.SetDefault(cfgAccountingFee, "1")

	v.SetDefault(cfgContainerContract, "9d2ca84d7fb88213c4baced5a6ed4dc402309039")
	v.SetDefault(cfgContainerFee, "1")

	v.SetDefault(cfgNetmapContract, "75194459637323ea8837d2afe8225ec74a5658c3")
	v.SetDefault(cfgNetmapFee, "1")

	v.SetDefault(cfgLogLevel, "info")
	v.SetDefault(cfgLogFormat, "console")
	v.SetDefault(cfgLogTrace, "fatal")
	v.SetDefault(cfgLogInitSampling, 1000)
	v.SetDefault(cfgLogThereafterSampling, 1000)

	v.SetDefault(cfgProfilerEnable, false)
	v.SetDefault(cfgProfilerAddr, ":6060")
	v.SetDefault(cfgProfilerTTL, "30s")

	v.SetDefault(cfgGCQueueSize, 1000)
	v.SetDefault(cfgGCQueueTick, "5s")
	v.SetDefault(cfgGCTimeout, "5s")

	v.SetDefault(cfgPolicerWorkScope, 100)
	v.SetDefault(cfgPolicerExpRate, 10) // in %
	v.SetDefault(cfgPolicerHeadTimeout, 5*time.Second)

	v.SetDefault(cfgReplicatorPutTimeout, 5*time.Second)

	v.SetDefault(cfgReBootstrapEnabled, false) // in epochs
	v.SetDefault(cfgReBootstrapInterval, 2)    // in epochs

	v.SetDefault(cfgObjectGetPoolSize, 10)
	v.SetDefault(cfgObjectHeadPoolSize, 10)
	v.SetDefault(cfgObjectPutPoolSize, 10)
	v.SetDefault(cfgObjectSearchPoolSize, 10)
	v.SetDefault(cfgObjectRangePoolSize, 10)
	v.SetDefault(cfgObjectRangeHashPoolSize, 10)
}

func (c *cfg) LocalAddress() *network.Address {
	return c.localAddr
}

func initLocalStorage(c *cfg) {
	initShardOptions(c)

	ls := engine.New(
		engine.WithLogger(c.log),
	)

	for _, opts := range c.cfgObject.cfgLocalStorage.shardOpts {
		id, err := ls.AddShard(opts...)
		fatalOnErr(err)

		c.log.Info("shard attached to engine",
			zap.Stringer("id", id),
		)
	}

	c.cfgObject.cfgLocalStorage.localStorage = ls
}

func initShardOptions(c *cfg) {
	var opts [][]shard.Option

	for i := 0; ; i++ {
		prefix := configPath(
			cfgLocalStorageSection,
			cfgStorageShardSection,
			strconv.Itoa(i),
		)

		useCache := c.viper.GetBool(
			configPath(prefix, cfgShardUseWriteCache),
		)

		writeCachePrefix := configPath(prefix, cfgWriteCacheSection)

		writeCachePath := c.viper.GetString(
			configPath(writeCachePrefix, cfgBlobStorTreePath),
		)
		if useCache && writeCachePath == "" {
			c.log.Warn("incorrect writeCache path, ignore shard")
			break
		}

		blobPrefix := configPath(prefix, cfgBlobStorSection)

		blobPath := c.viper.GetString(
			configPath(blobPrefix, cfgBlobStorTreePath),
		)
		if blobPath == "" {
			c.log.Warn("incorrect blobStor path, ignore shard")
			break
		}

		compressObjects := c.viper.GetBool(
			configPath(blobPrefix, cfgBlobStorCompress),
		)

		blobPerm := os.FileMode(c.viper.GetInt(
			configPath(blobPrefix, cfgBlobStorTreePerm),
		))

		shallowDepth := c.viper.GetInt(
			configPath(blobPrefix, cfgBlobStorShallowDepth),
		)

		smallSzLimit := c.viper.GetUint64(
			configPath(blobPrefix, cfgBlobStorSmallSzLimit),
		)

		blzPrefix := configPath(blobPrefix, cfgBlobStorBlzSection)

		blzSize := c.viper.GetUint64(
			configPath(blzPrefix, cfgBlzSize),
		)

		blzShallowDepth := c.viper.GetUint64(
			configPath(blzPrefix, cfgBlzShallowDepth),
		)

		blzShallowWidth := c.viper.GetUint64(
			configPath(blzPrefix, cfgBlzShallowWidth),
		)

		blzCacheSize := c.viper.GetInt(
			configPath(blzPrefix, cfgBlzOpenedCacheSize),
		)

		metaPrefix := configPath(prefix, cfgMetaBaseSection)

		metaPath := c.viper.GetString(
			configPath(metaPrefix, cfgMetaBasePath),
		)

		metaPerm := os.FileMode(c.viper.GetUint32(
			configPath(metaPrefix, cfgMetaBasePerm),
		))

		fatalOnErr(os.MkdirAll(path.Dir(metaPath), metaPerm))

		opts = append(opts, []shard.Option{
			shard.WithLogger(c.log),
			shard.WithBlobStorOptions(
				blobstor.WithRootPath(blobPath),
				blobstor.WithCompressObjects(compressObjects, c.log),
				blobstor.WithRootPerm(blobPerm),
				blobstor.WithShallowDepth(shallowDepth),
				blobstor.WithSmallSizeLimit(smallSzLimit),
				blobstor.WithBlobovniczaSize(blzSize),
				blobstor.WithBlobovniczaShallowDepth(blzShallowDepth),
				blobstor.WithBlobovniczaShallowWidth(blzShallowWidth),
				blobstor.WithBlobovniczaOpenedCacheSize(blzCacheSize),
				blobstor.WithLogger(c.log),
			),
			shard.WithMetaBaseOptions(
				meta.WithLogger(c.log),
				meta.WithPath(metaPath),
				meta.WithPermissions(metaPerm),
			),
			shard.WithWriteCache(useCache),
			shard.WithWriteCacheOptions(
				blobstor.WithRootPath(writeCachePath),
				blobstor.WithBlobovniczaShallowDepth(0),
				blobstor.WithBlobovniczaShallowWidth(1),
			),
		})

		c.log.Info("storage shard options",
			zap.Bool("with write cache", useCache),
			zap.String("with write cache path", writeCachePath),
			zap.String("BLOB path", blobPath),
			zap.Stringer("BLOB permissions", blobPerm),
			zap.Bool("BLOB compress", compressObjects),
			zap.Int("BLOB shallow depth", shallowDepth),
			zap.Uint64("BLOB small size limit", smallSzLimit),
			zap.String("metabase path", metaPath),
			zap.Stringer("metabase permissions", metaPerm),
		)
	}

	if len(opts) == 0 {
		fatalOnErr(errors.New("no correctly set up shards, exit"))
	}

	c.cfgObject.cfgLocalStorage.shardOpts = opts
}

func configPath(sections ...string) string {
	return strings.Join(sections, ".")
}

func initBucket(prefix string, c *cfg) (bucket bucket.Bucket, err error) {
	const inmemory = "inmemory"

	switch c.viper.GetString(prefix + ".type") {
	case inmemory:
		bucket = newBucket()
		c.log.Info("using in-memory bucket", zap.String("storage", prefix))
	case fsbucket.Name:
		bucket, err = fsbucket.NewBucket(prefix, c.viper)
		if err != nil {
			return nil, errors.Wrap(err, "can't create fs bucket")
		}
		c.log.Info("using filesystem bucket", zap.String("storage", prefix))
	default:
		return nil, errors.New("unknown storage type")
	}

	return bucket, nil
}

func initObjectPool(cfg *viper.Viper) (pool cfgObjectRoutines) {
	var err error

	optNonBlocking := ants.WithNonblocking(true)

	pool.get, err = ants.NewPool(cfg.GetInt(cfgObjectGetPoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	pool.head, err = ants.NewPool(cfg.GetInt(cfgObjectHeadPoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	pool.search, err = ants.NewPool(cfg.GetInt(cfgObjectSearchPoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	pool.put, err = ants.NewPool(cfg.GetInt(cfgObjectPutPoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	pool.rng, err = ants.NewPool(cfg.GetInt(cfgObjectRangePoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	pool.rngHash, err = ants.NewPool(cfg.GetInt(cfgObjectRangeHashPoolSize), optNonBlocking)
	if err != nil {
		fatalOnErr(err)
	}

	return pool
}