package policy

import (
	"git.frostfs.info/TrueCloudLab/frostfs-contract/common"
	"github.com/nspcc-dev/neo-go/pkg/interop/iterator"
	"github.com/nspcc-dev/neo-go/pkg/interop/storage"
)

// Kind represents the object the chain is attached to.
// Currently only namespace and container are supported.
type Kind byte

const (
	Namespace = 'n'
	Container = 'c'
	IAM       = 'i'
)

// _deploy function sets up initial list of inner ring public keys.
func _deploy(data any, isUpdate bool) {
}

func storageKey(prefix Kind, entityName, name string) []byte {
	ln := len(entityName)
	key := append([]byte{byte(prefix)}, byte(ln&0xFF), byte(ln>>8))
	key = append(key, entityName...)
	return append(key, name...)
}

func AddChain(entity Kind, entityName, name string, chain []byte) {
	common.CheckAlphabetWitness() // TODO: Allow to work with chain directly for everyone?

	ctx := storage.GetContext()
	key := storageKey(entity, entityName, name)
	storage.Put(ctx, key, chain)
}

func GetChain(entity Kind, entityName, name string) []byte {
	ctx := storage.GetReadOnlyContext()
	key := storageKey(entity, entityName, name)
	data := storage.Get(ctx, key).([]byte)
	if data == nil {
		panic("not found")
	}

	return data
}

func RemoveChain(entity Kind, entityName string, name string) {
	common.CheckAlphabetWitness()

	ctx := storage.GetContext()
	key := storageKey(entity, entityName, name)
	storage.Delete(ctx, key)
}

func RemoveChainsByPrefix(entity Kind, entityName string, name string) {
	common.CheckAlphabetWitness()

	ctx := storage.GetContext()
	key := storageKey(entity, entityName, name)
	it := storage.Find(ctx, key, storage.KeysOnly)
	for iterator.Next(it) {
		storage.Delete(ctx, iterator.Value(it).([]byte))
	}
}

// ListChains lists all chains for the namespace by prefix.
// container may be empty.
func ListChains(namespace, container, name string) [][]byte {
	ctx := storage.GetReadOnlyContext()

	var result [][]byte

	prefixNs := storageKey(Namespace, namespace, name)
	it := storage.Find(ctx, prefixNs, storage.ValuesOnly)
	for iterator.Next(it) {
		result = append(result, iterator.Value(it).([]byte))
	}

	if container != "" {
		prefixCnr := storageKey(Container, container, name)
		it = storage.Find(ctx, prefixCnr, storage.ValuesOnly)
		for iterator.Next(it) {
			result = append(result, iterator.Value(it).([]byte))
		}
	}

	return result
}

// ListChainsByPrefix list all chains for the provided kind and entity by prefix.
func ListChainsByPrefix(entity Kind, entityName, prefix string) [][]byte {
	ctx := storage.GetReadOnlyContext()

	result := [][]byte{}

	keyPrefix := storageKey(entity, entityName, prefix)
	it := storage.Find(ctx, keyPrefix, storage.ValuesOnly)
	for iterator.Next(it) {
		result = append(result, iterator.Value(it).([]byte))
	}

	return result
}