package util

import (
	"errors"
	"fmt"

	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/morph/client/netmap"
	"github.com/nspcc-dev/neo-go/pkg/io"
	"github.com/nspcc-dev/neo-go/pkg/rpcclient/invoker"
	"github.com/nspcc-dev/neo-go/pkg/rpcclient/management"
	"github.com/nspcc-dev/neo-go/pkg/rpcclient/unwrap"
	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
	"github.com/nspcc-dev/neo-go/pkg/util"
	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
	"github.com/spf13/viper"
)

var NetmapConfigKeys = []string{
	netmap.EpochDurationConfig,
	netmap.MaxObjectSizeConfig,
	netmap.ContainerFeeConfig,
	netmap.ContainerAliasFeeConfig,
	netmap.IrCandidateFeeConfig,
	netmap.WithdrawFeeConfig,
	netmap.HomomorphicHashingDisabledKey,
	netmap.MaintenanceModeAllowedConfig,
}

func GetDefaultNetmapContractConfigMap() map[string]any {
	m := make(map[string]any)
	m[netmap.EpochDurationConfig] = viper.GetInt64(EpochDurationInitFlag)
	m[netmap.MaxObjectSizeConfig] = viper.GetInt64(MaxObjectSizeInitFlag)
	m[netmap.ContainerFeeConfig] = viper.GetInt64(ContainerFeeInitFlag)
	m[netmap.ContainerAliasFeeConfig] = viper.GetInt64(ContainerAliasFeeInitFlag)
	m[netmap.IrCandidateFeeConfig] = viper.GetInt64(CandidateFeeInitFlag)
	m[netmap.WithdrawFeeConfig] = viper.GetInt64(WithdrawFeeInitFlag)
	m[netmap.HomomorphicHashingDisabledKey] = viper.GetBool(HomomorphicHashDisabledInitFlag)
	m[netmap.MaintenanceModeAllowedConfig] = viper.GetBool(MaintenanceModeAllowedInitFlag)
	return m
}

func ParseConfigFromNetmapContract(arr []stackitem.Item) (map[string][]byte, error) {
	m := make(map[string][]byte, len(arr))
	for _, param := range arr {
		tuple, ok := param.Value().([]stackitem.Item)
		if !ok || len(tuple) != 2 {
			return nil, errors.New("invalid ListConfig response from netmap contract")
		}

		k, err := tuple[0].TryBytes()
		if err != nil {
			return nil, errors.New("invalid config key from netmap contract")
		}

		v, err := tuple[1].TryBytes()
		if err != nil {
			return nil, InvalidConfigValueErr(string(k))
		}
		m[string(k)] = v
	}
	return m, nil
}

func InvalidConfigValueErr(key string) error {
	return fmt.Errorf("invalid %s config value from netmap contract", key)
}

func EmitNewEpochCall(bw *io.BufBinWriter, wCtx *InitializeContext, nmHash util.Uint160) error {
	curr, err := unwrap.Int64(wCtx.ReadOnlyInvoker.Call(nmHash, "epoch"))
	if err != nil {
		return errors.New("can't fetch current epoch from the netmap contract")
	}

	newEpoch := curr + 1
	wCtx.Command.Printf("Current epoch: %d, increase to %d.\n", curr, newEpoch)

	// In NeoFS this is done via Notary contract. Here, however, we can form the
	// transaction locally.
	emit.AppCall(bw.BinWriter, nmHash, "newEpoch", callflag.All, newEpoch)
	return bw.Err
}

func GetNetConfigFromNetmapContract(roInvoker *invoker.Invoker) ([]stackitem.Item, error) {
	r := management.NewReader(roInvoker)
	cs, err := r.GetContractByID(1)
	if err != nil {
		return nil, fmt.Errorf("get nns contract: %w", err)
	}
	nmHash, err := NNSResolveHash(roInvoker, cs.Hash, DomainOf(NetmapContract))
	if err != nil {
		return nil, fmt.Errorf("can't get netmap contract hash: %w", err)
	}
	arr, err := unwrap.Array(roInvoker.Call(nmHash, "listConfig"))
	if err != nil {
		return nil, fmt.Errorf("can't fetch list of network config keys from the netmap contract")
	}
	return arr, err
}

func MergeNetmapConfig(roInvoker *invoker.Invoker, md map[string]any) error {
	arr, err := GetNetConfigFromNetmapContract(roInvoker)
	if err != nil {
		return err
	}
	m, err := ParseConfigFromNetmapContract(arr)
	if err != nil {
		return err
	}
	for k, v := range m {
		for _, key := range NetmapConfigKeys {
			if k == key {
				md[k] = v
				break
			}
		}
	}
	return nil
}