package api

import (
	"encoding/json"
	"fmt"

	datatransfer "github.com/filecoin-project/go-data-transfer"
	"github.com/filecoin-project/go-state-types/abi"
	"github.com/filecoin-project/lotus/build"
	"github.com/ipfs/go-cid"

	"github.com/libp2p/go-libp2p-core/peer"
	pubsub "github.com/libp2p/go-libp2p-pubsub"
	ma "github.com/multiformats/go-multiaddr"
)

// TODO: check if this exists anywhere else

type MultiaddrSlice []ma.Multiaddr

func (m *MultiaddrSlice) UnmarshalJSON(raw []byte) (err error) {
	var temp []string
	if err := json.Unmarshal(raw, &temp); err != nil {
		return err
	}

	res := make([]ma.Multiaddr, len(temp))
	for i, str := range temp {
		res[i], err = ma.NewMultiaddr(str)
		if err != nil {
			return err
		}
	}
	*m = res
	return nil
}

var _ json.Unmarshaler = new(MultiaddrSlice)

type ObjStat struct {
	Size  uint64
	Links uint64
}

type PubsubScore struct {
	ID    peer.ID
	Score *pubsub.PeerScoreSnapshot
}

type MessageSendSpec struct {
	MaxFee abi.TokenAmount
}

var DefaultMessageSendSpec = MessageSendSpec{
	// MaxFee of 0.1FIL
	MaxFee: abi.NewTokenAmount(int64(build.FilecoinPrecision) / 10),
}

func (ms *MessageSendSpec) Get() MessageSendSpec {
	if ms == nil {
		return DefaultMessageSendSpec
	}

	return *ms
}

type DataTransferChannel struct {
	TransferID  datatransfer.TransferID
	Status      datatransfer.Status
	BaseCID     cid.Cid
	IsInitiator bool
	IsSender    bool
	Voucher     string
	Message     string
	OtherPeer   peer.ID
	Transferred uint64
}

// NewDataTransferChannel constructs an API DataTransferChannel type from full channel state snapshot and a host id
func NewDataTransferChannel(hostID peer.ID, channelState datatransfer.ChannelState) DataTransferChannel {
	channel := DataTransferChannel{
		TransferID: channelState.TransferID(),
		Status:     channelState.Status(),
		BaseCID:    channelState.BaseCID(),
		IsSender:   channelState.Sender() == hostID,
		Message:    channelState.Message(),
	}
	stringer, ok := channelState.Voucher().(fmt.Stringer)
	if ok {
		channel.Voucher = stringer.String()
	} else {
		voucherJSON, err := json.Marshal(channelState.Voucher())
		if err != nil {
			channel.Voucher = fmt.Errorf("Voucher Serialization: %w", err).Error()
		} else {
			channel.Voucher = string(voucherJSON)
		}
	}
	if channel.IsSender {
		channel.IsInitiator = !channelState.IsPull()
		channel.Transferred = channelState.Sent()
		channel.OtherPeer = channelState.Recipient()
	} else {
		channel.IsInitiator = channelState.IsPull()
		channel.Transferred = channelState.Received()
		channel.OtherPeer = channelState.Sender()
	}
	return channel
}