package neofsid

import (
	"github.com/nspcc-dev/neo-go/pkg/interop"
	"github.com/nspcc-dev/neo-go/pkg/interop/contract"
	"github.com/nspcc-dev/neo-go/pkg/interop/iterator"
	"github.com/nspcc-dev/neo-go/pkg/interop/native/crypto"
	"github.com/nspcc-dev/neo-go/pkg/interop/native/management"
	"github.com/nspcc-dev/neo-go/pkg/interop/runtime"
	"github.com/nspcc-dev/neo-go/pkg/interop/storage"
	"github.com/nspcc-dev/neofs-contract/common"
)

type (
	UserInfo struct {
		Keys [][]byte
	}
)

const (
	ownerSize = 1 + interop.Hash160Len + 4
)

const (
	netmapContractKey    = "netmapScriptHash"
	containerContractKey = "containerScriptHash"
	notaryDisabledKey    = "notary"
	ownerKeysPrefix      = 'o'
)

func _deploy(data interface{}, isUpdate bool) {
	ctx := storage.GetContext()

	if isUpdate {
		storage.Delete(ctx, common.LegacyOwnerKey)
		return
	}

	args := data.(struct {
		notaryDisabled bool
		addrNetmap     interop.Hash160
		addrContainer  interop.Hash160
	})

	if len(args.addrNetmap) != interop.Hash160Len || len(args.addrContainer) != interop.Hash160Len {
		panic("incorrect length of contract script hash")
	}

	storage.Put(ctx, netmapContractKey, args.addrNetmap)
	storage.Put(ctx, containerContractKey, args.addrContainer)

	// initialize the way to collect signatures
	storage.Put(ctx, notaryDisabledKey, args.notaryDisabled)
	if args.notaryDisabled {
		common.InitVote(ctx)
		runtime.Log("neofsid contract notary disabled")
	}

	runtime.Log("neofsid contract initialized")
}

// Update method updates contract source code and manifest. Can be invoked
// only by committee.
func Update(script []byte, manifest []byte, data interface{}) {
	if !common.HasUpdateAccess() {
		panic("only committee can update contract")
	}

	contract.Call(interop.Hash160(management.Hash), "update",
		contract.All, script, manifest, common.AppendVersion(data))
	runtime.Log("neofsid contract updated")
}

// AddKey binds list of provided public keys to OwnerID. Can be invoked only by
// Alphabet nodes.
//
// This method panics if OwnerID is not ownerSize byte or public key is not 33 byte long.
// If key is already bound, ignores it.
func AddKey(owner []byte, keys []interop.PublicKey) {
	// V2 format
	if len(owner) != ownerSize {
		panic("incorrect owner")
	}

	for i := range keys {
		if len(keys[i]) != interop.PublicKeyCompressedLen {
			panic("incorrect public key")
		}
	}

	ctx := storage.GetContext()
	notaryDisabled := storage.Get(ctx, notaryDisabledKey).(bool)

	var ( // for invocation collection without notary
		alphabet     []common.IRNode
		nodeKey      []byte
		indirectCall bool
	)

	if notaryDisabled {
		alphabet = common.AlphabetNodes()
		nodeKey = common.InnerRingInvoker(alphabet)
		if len(nodeKey) == 0 {
			panic("invocation from non inner ring node")
		}

		indirectCall = common.FromKnownContract(
			ctx,
			runtime.GetCallingScriptHash(),
			containerContractKey)

		if indirectCall {
			threshold := len(alphabet)*2/3 + 1
			id := invokeIDKeys(owner, keys, []byte("add"))

			n := common.Vote(ctx, id, nodeKey)
			if n < threshold {
				return
			}

			common.RemoveVotes(ctx, id)
		}
	} else {
		multiaddr := common.AlphabetAddress()
		common.CheckAlphabetWitness(multiaddr)
	}

	ownerKey := append([]byte{ownerKeysPrefix}, owner...)
	for i := range keys {
		stKey := append(ownerKey, keys[i]...)
		storage.Put(ctx, stKey, []byte{1})
	}

	runtime.Log("key bound to the owner")
}

// RemoveKey unbinds provided public keys from OwnerID. Can be invoked only by
// Alphabet nodes.
//
// This method panics if OwnerID is not ownerSize byte or public key is not 33 byte long.
// If key is already unbound, ignores it.
func RemoveKey(owner []byte, keys []interop.PublicKey) {
	// V2 format
	if len(owner) != ownerSize {
		panic("incorrect owner")
	}

	for i := range keys {
		if len(keys[i]) != interop.PublicKeyCompressedLen {
			panic("incorrect public key")
		}
	}

	ctx := storage.GetContext()
	notaryDisabled := storage.Get(ctx, notaryDisabledKey).(bool)

	var ( // for invocation collection without notary
		alphabet []common.IRNode
		nodeKey  []byte
	)

	if notaryDisabled {
		alphabet = common.AlphabetNodes()
		nodeKey = common.InnerRingInvoker(alphabet)
		if len(nodeKey) == 0 {
			panic("invocation from non inner ring node")
		}

		threshold := len(alphabet)*2/3 + 1
		id := invokeIDKeys(owner, keys, []byte("remove"))

		n := common.Vote(ctx, id, nodeKey)
		if n < threshold {
			return
		}

		common.RemoveVotes(ctx, id)
	} else {
		multiaddr := common.AlphabetAddress()
		if !runtime.CheckWitness(multiaddr) {
			panic("invocation from non inner ring node")
		}
	}

	ownerKey := append([]byte{ownerKeysPrefix}, owner...)
	for i := range keys {
		stKey := append(ownerKey, keys[i]...)
		storage.Delete(ctx, stKey)
	}
}

// Key method returns list of 33-byte public keys bound with OwnerID.
//
// This method panics if owner is not ownerSize byte long.
func Key(owner []byte) [][]byte {
	// V2 format
	if len(owner) != ownerSize {
		panic("incorrect owner")
	}

	ctx := storage.GetReadOnlyContext()

	ownerKey := append([]byte{ownerKeysPrefix}, owner...)
	info := getUserInfo(ctx, ownerKey)

	return info.Keys
}

// Version returns version of the contract.
func Version() int {
	return common.Version
}

func getUserInfo(ctx storage.Context, key interface{}) UserInfo {
	it := storage.Find(ctx, key, storage.KeysOnly|storage.RemovePrefix)
	pubs := [][]byte{}
	for iterator.Next(it) {
		pub := iterator.Value(it).([]byte)
		pubs = append(pubs, pub)
	}

	return UserInfo{Keys: pubs}
}

func invokeIDKeys(owner []byte, keys []interop.PublicKey, prefix []byte) []byte {
	prefix = append(prefix, owner...)
	for i := range keys {
		prefix = append(prefix, keys[i]...)
	}

	return crypto.Sha256(prefix)
}