//go:generate mockgen -destination mock_commonspace/mock_commonspace.go github.com/anyproto/any-sync/commonspace Space
package commonspace

import (
	"context"
	"errors"
	"sync/atomic"
	"time"

	"go.uber.org/zap"

	"storj.io/drpc"

	"github.com/anyproto/any-sync/commonspace/acl/aclclient"
	"github.com/anyproto/any-sync/commonspace/deletionmanager"
	"github.com/anyproto/any-sync/commonspace/object/acl/list"
	"github.com/anyproto/any-sync/commonspace/object/acl/recordverifier"
	"github.com/anyproto/any-sync/commonspace/object/keyvalue"
	"github.com/anyproto/any-sync/commonspace/object/keyvalue/keyvaluestorage"
	"github.com/anyproto/any-sync/commonspace/object/treesyncer"
	"github.com/anyproto/any-sync/commonspace/spacepayloads"
	"github.com/anyproto/any-sync/commonspace/sync"
	"github.com/anyproto/any-sync/commonspace/sync/objectsync"
	"github.com/anyproto/any-sync/net"
	"github.com/anyproto/any-sync/net/peer"
	"github.com/anyproto/any-sync/net/pool"

	"github.com/anyproto/any-sync/accountservice"
	"github.com/anyproto/any-sync/app"
	"github.com/anyproto/any-sync/app/logger"
	"github.com/anyproto/any-sync/commonspace/config"
	"github.com/anyproto/any-sync/commonspace/credentialprovider"
	"github.com/anyproto/any-sync/commonspace/deletionstate"
	"github.com/anyproto/any-sync/commonspace/headsync"
	"github.com/anyproto/any-sync/commonspace/object/acl/syncacl"
	"github.com/anyproto/any-sync/commonspace/object/tree/objecttree"
	"github.com/anyproto/any-sync/commonspace/object/tree/treechangeproto"
	"github.com/anyproto/any-sync/commonspace/object/treemanager"
	"github.com/anyproto/any-sync/commonspace/objectmanager"
	"github.com/anyproto/any-sync/commonspace/objecttreebuilder"
	"github.com/anyproto/any-sync/commonspace/peermanager"
	"github.com/anyproto/any-sync/commonspace/settings"
	"github.com/anyproto/any-sync/commonspace/spacestate"
	"github.com/anyproto/any-sync/commonspace/spacestorage"
	"github.com/anyproto/any-sync/commonspace/spacesyncproto"
	"github.com/anyproto/any-sync/commonspace/syncstatus"
	"github.com/anyproto/any-sync/consensus/consensusproto"
	"github.com/anyproto/any-sync/metric"
	"github.com/anyproto/any-sync/net/rpc/rpcerr"
	"github.com/anyproto/any-sync/nodeconf"
)

const CName = "common.commonspace"

var log = logger.NewNamed(CName)

func New() SpaceService {
	return &spaceService{}
}

type ctxKey int

const AddSpaceCtxKey ctxKey = 0

type SpaceService interface {
	DeriveSpace(ctx context.Context, payload spacepayloads.SpaceDerivePayload) (string, error)
	DeriveId(ctx context.Context, payload spacepayloads.SpaceDerivePayload) (string, error)
	CreateSpace(ctx context.Context, payload spacepayloads.SpaceCreatePayload) (string, error)
	NewSpace(ctx context.Context, id string, deps Deps) (sp Space, err error)
	app.Component
}

type Deps struct {
	SyncStatus     syncstatus.StatusUpdater
	TreeSyncer     treesyncer.TreeSyncer
	AccountService accountservice.Service
	recordVerifier recordverifier.RecordVerifier
	Indexer        keyvaluestorage.Indexer
}

type spaceService struct {
	config               config.Config
	account              accountservice.Service
	configurationService nodeconf.Service
	storageProvider      spacestorage.SpaceStorageProvider
	peerManagerProvider  peermanager.PeerManagerProvider
	credentialProvider   credentialprovider.CredentialProvider
	treeManager          treemanager.TreeManager
	metric               metric.Metric
	app                  *app.App
	pool                 pool.Pool
}

func (s *spaceService) Init(a *app.App) (err error) {
	s.config = a.MustComponent("config").(config.ConfigGetter).GetSpace()
	s.account = a.MustComponent(accountservice.CName).(accountservice.Service)
	s.storageProvider = a.MustComponent(spacestorage.CName).(spacestorage.SpaceStorageProvider)
	s.configurationService = a.MustComponent(nodeconf.CName).(nodeconf.Service)
	s.treeManager = a.MustComponent(treemanager.CName).(treemanager.TreeManager)
	s.peerManagerProvider = a.MustComponent(peermanager.CName).(peermanager.PeerManagerProvider)
	s.pool = a.MustComponent(pool.CName).(pool.Pool)
	s.metric, _ = a.Component(metric.CName).(metric.Metric)
	s.app = a
	return nil
}

func (s *spaceService) Name() (name string) {
	return CName
}

func (s *spaceService) CreateSpace(ctx context.Context, payload spacepayloads.SpaceCreatePayload) (id string, err error) {
	storageCreate, err := spacepayloads.StoragePayloadForSpaceCreate(payload)
	if err != nil {
		return
	}
	store, err := s.createSpaceStorage(ctx, storageCreate)
	if err != nil {
		if errors.Is(err, spacestorage.ErrSpaceStorageExists) {
			return storageCreate.SpaceHeaderWithId.Id, nil
		}
		return
	}

	return store.Id(), store.Close(ctx)
}

func (s *spaceService) DeriveId(ctx context.Context, payload spacepayloads.SpaceDerivePayload) (id string, err error) {
	storageCreate, err := spacepayloads.StoragePayloadForSpaceDerive(payload)
	if err != nil {
		return
	}
	id = storageCreate.SpaceHeaderWithId.Id
	return
}

func (s *spaceService) DeriveSpace(ctx context.Context, payload spacepayloads.SpaceDerivePayload) (id string, err error) {
	storageCreate, err := spacepayloads.StoragePayloadForSpaceDerive(payload)
	if err != nil {
		return
	}
	store, err := s.createSpaceStorage(ctx, storageCreate)
	if err != nil {
		if errors.Is(err, spacestorage.ErrSpaceStorageExists) {
			return storageCreate.SpaceHeaderWithId.Id, nil
		}
		return
	}

	return store.Id(), store.Close(ctx)
}

func (s *spaceService) NewSpace(ctx context.Context, id string, deps Deps) (Space, error) {
	st, err := s.storageProvider.WaitSpaceStorage(ctx, id)
	if err != nil {
		if !errors.Is(err, spacestorage.ErrSpaceStorageMissing) {
			return nil, err
		}

		if description, ok := ctx.Value(AddSpaceCtxKey).(SpaceDescription); ok {
			st, err = s.addSpaceStorage(ctx, description)
			if err != nil {
				return nil, err
			}
		} else {
			st, err = s.getSpaceStorageFromRemote(ctx, id, deps)
			if err != nil {
				return nil, err
			}
		}
	}
	spaceIsClosed := &atomic.Bool{}
	state := &spacestate.SpaceState{
		SpaceId:       st.Id(),
		SpaceIsClosed: spaceIsClosed,
		TreesUsed:     &atomic.Int32{},
	}
	if s.config.KeepTreeDataInMemory {
		state.TreeBuilderFunc = objecttree.BuildObjectTree
	} else {
		state.TreeBuilderFunc = objecttree.BuildEmptyDataObjectTree
	}
	peerManager, err := s.peerManagerProvider.NewPeerManager(ctx, id)
	if err != nil {
		return nil, err
	}
	spaceApp := s.app.ChildApp()
	if deps.AccountService != nil {
		spaceApp.Register(deps.AccountService)
	}
	var keyValueIndexer keyvaluestorage.Indexer = keyvaluestorage.NoOpIndexer{}
	if deps.Indexer != nil {
		keyValueIndexer = deps.Indexer
	}
	recordVerifier := recordverifier.New()
	if deps.recordVerifier != nil {
		recordVerifier = deps.recordVerifier
	}
	spaceApp.Register(state).
		Register(deps.SyncStatus).
		Register(recordVerifier).
		Register(peerManager).
		Register(st).
		Register(keyValueIndexer).
		Register(objectsync.New()).
		Register(sync.NewSyncService()).
		Register(syncacl.New()).
		Register(keyvalue.New()).
		Register(deletionstate.New()).
		Register(deletionmanager.New()).
		Register(settings.New()).
		Register(objectmanager.New(s.treeManager)).
		Register(deps.TreeSyncer).
		Register(objecttreebuilder.New()).
		Register(aclclient.NewAclSpaceClient()).
		Register(headsync.New())
	sp := &space{
		state:   state,
		app:     spaceApp,
		storage: st,
	}
	return sp, nil
}

func (s *spaceService) addSpaceStorage(ctx context.Context, spaceDescription SpaceDescription) (st spacestorage.SpaceStorage, err error) {
	payload := spacestorage.SpaceStorageCreatePayload{
		AclWithId: &consensusproto.RawRecordWithId{
			Payload: spaceDescription.AclPayload,
			Id:      spaceDescription.AclId,
		},
		SpaceHeaderWithId: spaceDescription.SpaceHeader,
		SpaceSettingsWithId: &treechangeproto.RawTreeChangeWithId{
			RawChange: spaceDescription.SpaceSettingsPayload,
			Id:        spaceDescription.SpaceSettingsId,
		},
	}
	st, err = s.createSpaceStorage(ctx, payload)
	if err != nil {
		err = spacesyncproto.ErrUnexpected
		if errors.Is(err, spacestorage.ErrSpaceStorageExists) {
			err = spacesyncproto.ErrSpaceExists
		}
		return
	}
	return
}

func (s *spaceService) getSpaceStorageFromRemote(ctx context.Context, id string, deps Deps) (st spacestorage.SpaceStorage, err error) {
	// we can't connect to client if it is a node
	if s.configurationService.IsResponsible(id) {
		err = spacesyncproto.ErrSpaceMissing
		return
	}

	pm, err := s.peerManagerProvider.NewPeerManager(ctx, id)
	if err != nil {
		return nil, err
	}
	peerApp := s.app.ChildApp().Register(pm)
	err = peerApp.Start(ctx)
	if err != nil {
		return
	}
	defer func() {
		err := peerApp.Close(ctx)
		if err != nil {
			log.Warn("failed to close peer manager")
		}
	}()
	var peers []peer.Peer
	for {
		peers, err = pm.GetResponsiblePeers(ctx)
		if err != nil && !errors.Is(err, net.ErrUnableToConnect) {
			return nil, err
		}
		if len(peers) == 0 {
			select {
			case <-time.After(time.Second):
			case <-ctx.Done():
				return nil, ctx.Err()
			}
		} else {
			break
		}
	}
	for i, p := range peers {
		if st, err = s.spacePullWithPeer(ctx, p, id, deps); err != nil {
			if i+1 == len(peers) {
				return
			} else {
				log.InfoCtx(ctx, "unable to pull space", zap.String("spaceId", id), zap.String("peerId", p.Id()))
			}
		} else {
			return
		}
	}
	return nil, net.ErrUnableToConnect
}

func (s *spaceService) spacePullWithPeer(ctx context.Context, p peer.Peer, id string, deps Deps) (st spacestorage.SpaceStorage, err error) {
	var res *spacesyncproto.SpacePullResponse
	err = p.DoDrpc(ctx, func(conn drpc.Conn) error {
		cl := spacesyncproto.NewDRPCSpaceSyncClient(conn)
		res, err = cl.SpacePull(ctx, &spacesyncproto.SpacePullRequest{Id: id})
		return err
	})
	if err != nil {
		err = rpcerr.Unwrap(err)
		return
	}

	st, err = s.createSpaceStorage(ctx, spacestorage.SpaceStorageCreatePayload{
		AclWithId: &consensusproto.RawRecordWithId{
			Payload: res.Payload.AclPayload,
			Id:      res.Payload.AclPayloadId,
		},
		SpaceSettingsWithId: &treechangeproto.RawTreeChangeWithId{
			RawChange: res.Payload.SpaceSettingsPayload,
			Id:        res.Payload.SpaceSettingsPayloadId,
		},
		SpaceHeaderWithId: res.Payload.SpaceHeader,
	})
	if err != nil {
		return
	}
	if res.AclRecords != nil {
		aclSt, err := st.AclStorage()
		if err != nil {
			return nil, err
		}
		recordVerifier := recordverifier.New()
		if deps.recordVerifier != nil {
			recordVerifier = deps.recordVerifier
		}
		acl, err := list.BuildAclListWithIdentity(s.account.Account(), aclSt, recordVerifier)
		if err != nil {
			return nil, err
		}
		consRecs := make([]*consensusproto.RawRecordWithId, 0, len(res.AclRecords))
		for _, rec := range res.AclRecords {
			consRecs = append(consRecs, &consensusproto.RawRecordWithId{
				Id:      rec.Id,
				Payload: rec.AclPayload,
			})
		}
		err = acl.AddRawRecords(consRecs)
		if err != nil {
			return nil, err
		}
	}
	return st, nil
}

func (s *spaceService) createSpaceStorage(ctx context.Context, payload spacestorage.SpaceStorageCreatePayload) (spacestorage.SpaceStorage, error) {
	err := spacepayloads.ValidateSpaceStorageCreatePayload(payload)
	if err != nil {
		return nil, err
	}
	return s.storageProvider.CreateSpaceStorage(ctx, payload)
}