package wrapper

import (
	"fmt"
	"strconv"

	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
	"github.com/nspcc-dev/neofs-node/pkg/morph/client/netmap"
)

const (
	maxObjectSizeConfig     = "MaxObjectSize"
	basicIncomeRateConfig   = "BasicIncomeRate"
	auditFeeConfig          = "AuditFee"
	epochDurationConfig     = "EpochDuration"
	containerFeeConfig      = "ContainerFee"
	containerAliasFeeConfig = "ContainerAliasFee"
	etIterationsConfig      = "EigenTrustIterations"
	etAlphaConfig           = "EigenTrustAlpha"
	irCandidateFeeConfig    = "InnerRingCandidateFee"
	withdrawFeeConfig       = "WithdrawFee"
)

// MaxObjectSize receives max object size configuration
// value through the Netmap contract call.
func (w *Wrapper) MaxObjectSize() (uint64, error) {
	objectSize, err := w.readUInt64Config(maxObjectSizeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get epoch number: %w", w, err)
	}

	return objectSize, nil
}

// BasicIncomeRate returns basic income rate configuration value from network
// config in netmap contract.
func (w *Wrapper) BasicIncomeRate() (uint64, error) {
	rate, err := w.readUInt64Config(basicIncomeRateConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get basic income rate: %w", w, err)
	}

	return rate, nil
}

// AuditFee returns audit fee configuration value from network
// config in netmap contract.
func (w *Wrapper) AuditFee() (uint64, error) {
	fee, err := w.readUInt64Config(auditFeeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get audit fee: %w", w, err)
	}

	return fee, nil
}

// EpochDuration returns number of sidechain blocks per one NeoFS epoch.
func (w *Wrapper) EpochDuration() (uint64, error) {
	epochDuration, err := w.readUInt64Config(epochDurationConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get epoch duration: %w", w, err)
	}

	return epochDuration, nil
}

// ContainerFee returns fee paid by container owner to each alphabet node
// for container registration.
func (w *Wrapper) ContainerFee() (uint64, error) {
	fee, err := w.readUInt64Config(containerFeeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get container fee: %w", w, err)
	}

	return fee, nil
}

// ContainerAliasFee returns additional fee paid by container owner to each
// alphabet node for container nice name registration.
func (w *Wrapper) ContainerAliasFee() (uint64, error) {
	fee, err := w.readUInt64Config(containerAliasFeeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get container alias fee: %w", w, err)
	}

	return fee, nil
}

// EigenTrustIterations returns global configuration value of iteration cycles
// for EigenTrust algorithm per epoch.
func (w *Wrapper) EigenTrustIterations() (uint64, error) {
	iterations, err := w.readUInt64Config(etIterationsConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get eigen trust iterations: %w", w, err)
	}

	return iterations, nil
}

// EigenTrustAlpha returns global configuration value of alpha parameter.
// It receives the alpha as a string and tries to convert it to float.
func (w *Wrapper) EigenTrustAlpha() (float64, error) {
	strAlpha, err := w.readStringConfig(etAlphaConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get eigen trust alpha: %w", w, err)
	}

	return strconv.ParseFloat(strAlpha, 64)
}

// InnerRingCandidateFee returns global configuration value of fee paid by
// node to be in inner ring candidates list.
func (w *Wrapper) InnerRingCandidateFee() (uint64, error) {
	fee, err := w.readUInt64Config(irCandidateFeeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get inner ring candidate fee: %w", w, err)
	}

	return fee, nil
}

// WithdrawFee returns global configuration value of fee paid by user to
// withdraw assets from NeoFS contract.
func (w *Wrapper) WithdrawFee() (uint64, error) {
	fee, err := w.readUInt64Config(withdrawFeeConfig)
	if err != nil {
		return 0, fmt.Errorf("(%T) could not get withdraw fee: %w", w, err)
	}

	return fee, nil
}

func (w *Wrapper) readUInt64Config(key string) (uint64, error) {
	args := netmap.ConfigArgs{}
	args.SetKey([]byte(key))

	vals, err := w.client.Config(args, netmap.IntegerAssert)
	if err != nil {
		return 0, err
	}

	v := vals.Value()

	numeric, ok := v.(int64)
	if !ok {
		return 0, fmt.Errorf("(%T) invalid value type %T", w, v)
	}

	return uint64(numeric), nil
}

func (w *Wrapper) readStringConfig(key string) (string, error) {
	args := netmap.ConfigArgs{}
	args.SetKey([]byte(key))

	vals, err := w.client.Config(args, netmap.StringAssert)
	if err != nil {
		return "", err
	}

	v := vals.Value()

	str, ok := v.(string)
	if !ok {
		return "", fmt.Errorf("(%T) invalid value type %T", w, v)
	}

	return str, nil
}

// SetConfig sets config field.
func (w *Wrapper) SetConfig(id, key []byte, value interface{}) error {
	return w.client.SetConfig(id, key, value)
}

// IterateConfigParameters iterates over configuration parameters stored in Netmap contract and passes them to f.
//
// Returns f's errors directly.
func (w *Wrapper) IterateConfigParameters(f func(key, value []byte) error) error {
	var args netmap.ListConfigArgs

	v, err := w.client.ListConfig(args)
	if err != nil {
		return fmt.Errorf("client error: %w", err)
	}

	return v.IterateRecords(func(key, value []byte) error {
		return f(key, value)
	})
}

// ConfigWriter is an interface of NeoFS network config writer.
type ConfigWriter interface {
	UnknownParameter(string, []byte)
	MaxObjectSize(uint64)
	BasicIncomeRate(uint64)
	AuditFee(uint64)
	EpochDuration(uint64)
	ContainerFee(uint64)
	ContainerAliasFee(uint64)
	EigenTrustIterations(uint64)
	EigenTrustAlpha(float64)
	InnerRingCandidateFee(uint64)
	WithdrawFee(uint64)
}

// WriteConfig writes NeoFS network configuration received via iterator.
//
// Returns iterator's errors directly.
func WriteConfig(dst ConfigWriter, iterator func(func(key, val []byte) error) error) error {
	return iterator(func(key, val []byte) error {
		switch k := string(key); k {
		default:
			dst.UnknownParameter(k, val)
		case maxObjectSizeConfig:
			dst.MaxObjectSize(bigint.FromBytes(val).Uint64())
		case basicIncomeRateConfig:
			dst.BasicIncomeRate(bigint.FromBytes(val).Uint64())
		case auditFeeConfig:
			dst.AuditFee(bigint.FromBytes(val).Uint64())
		case epochDurationConfig:
			dst.EpochDuration(bigint.FromBytes(val).Uint64())
		case containerFeeConfig:
			dst.ContainerFee(bigint.FromBytes(val).Uint64())
		case containerAliasFeeConfig:
			dst.ContainerAliasFee(bigint.FromBytes(val).Uint64())
		case etIterationsConfig:
			dst.EigenTrustIterations(bigint.FromBytes(val).Uint64())
		case etAlphaConfig:
			v, err := strconv.ParseFloat(string(val), 64)
			if err != nil {
				return fmt.Errorf("prm %s: %v", etAlphaConfig, err)
			}

			dst.EigenTrustAlpha(v)
		case irCandidateFeeConfig:
			dst.InnerRingCandidateFee(bigint.FromBytes(val).Uint64())
		case withdrawFeeConfig:
			dst.WithdrawFee(bigint.FromBytes(val).Uint64())
		}

		return nil
	})
}