api.go

package lightning

import (
	"context"
	"encoding/json"
	"fmt"
	"math"
	"strings"
	"time"

	entities "github.com/bolt-observer/go_common/entities"
	"github.com/getsentry/sentry-go"
	"github.com/golang/glog"
)

// APIType enum.
type APIType int

// ApiTypes.
const (
	LndGrpc APIType = iota
	LndRest
	ClnSocket
	ClnCommando
)

// GetAPIType from integer.
func GetAPIType(t *int) (*APIType, error) {
	if t == nil {
		return nil, fmt.Errorf("no api type specified")
	}
	if *t != int(LndGrpc) && *t != int(LndRest) && *t != int(ClnSocket) && *t != int(ClnCommando) {
		return nil, fmt.Errorf("invalid api type specified")
	}

	ret := APIType(*t)
	return &ret, nil
}

// InfoAPI struct.
type InfoAPI struct {
	IdentityPubkey  string
	Alias           string
	Chain           string
	Network         string
	Version         string
	IsSyncedToGraph bool
	IsSyncedToChain bool
	BlockHeight     int
}

// ChannelsAPI struct.
type ChannelsAPI struct {
	Channels []ChannelAPI
}

// ChannelAPI struct.
type ChannelAPI struct {
	Private               bool
	Active                bool
	RemotePubkey          string
	Initiator             bool
	CommitFee             uint64
	ChanID                uint64
	RemoteBalance         uint64
	LocalBalance          uint64
	Capacity              uint64
	PendingHtlcs          []HtlcAPI
	TotalSatoshisSent     uint64
	TotalSatoshisReceived uint64
	NumUpdates            uint64
}

// HtlcAPI struct.
type HtlcAPI struct {
	Amount              uint64
	Incoming            bool
	ForwardingChannel   uint64
	ForwardingHtlcIndex uint64
}

// DescribeGraphAPI struct.
type DescribeGraphAPI struct {
	Nodes    []DescribeGraphNodeAPI
	Channels []NodeChannelAPI
}

// DescribeGraphNodeAPI struct.
type DescribeGraphNodeAPI struct {
	PubKey     string                    `json:"pub_key,omitempty"`
	Alias      string                    `json:"alias,omitempty"`
	Color      string                    `json:"color,omitempty"`
	Addresses  []NodeAddressAPI          `json:"addresses,omitempty"`
	Features   map[string]NodeFeatureAPI `json:"features,omitempty"`
	LastUpdate entities.JsonTime         `json:"last_update,omitempty"`
}

// NodeAddressAPI struct.
type NodeAddressAPI struct {
	Network string `json:"network,omitempty"`
	Addr    string `json:"addr,omitempty"`
}

// NodeFeatureAPI struct.
type NodeFeatureAPI struct {
	Name       string `json:"name,omitempty"`
	IsRequired bool   `json:"is_required,omitempty"`
	IsKnown    bool   `json:"is_known,omitempty"`
}

// NodeChannelAPI struct.
type NodeChannelAPI struct {
	ChannelID   uint64            `json:"channel_id,omitempty"`
	ChanPoint   string            `json:"chan_point"`
	Node1Pub    string            `json:"node1_pub,omitempty"`
	Node2Pub    string            `json:"node2_pub,omitempty"`
	Capacity    uint64            `json:"capacity,omitempty"`
	Node1Policy *RoutingPolicyAPI `json:"node1_policy,omitempty"`
	Node2Policy *RoutingPolicyAPI `json:"node2_policy,omitempty"`
	LastUpdate  entities.JsonTime `json:"last_update,omitempty"`
}

// RoutingPolicyAPI struct.
type RoutingPolicyAPI struct {
	TimeLockDelta uint32            `json:"time_lock_delta"`
	MinHtlc       uint64            `json:"min_htlc"`
	BaseFee       uint64            `json:"fee_base_msat"`
	FeeRate       uint64            `json:"fee_rate_milli_msat"`
	Disabled      bool              `json:"disabled,omitempty"`
	LastUpdate    entities.JsonTime `json:"last_update,omitempty"`
	MaxHtlc       uint64            `json:"max_htlc_msat"`
}

// NodeInfoAPI struct.
type NodeInfoAPI struct {
	Node          DescribeGraphNodeAPI `json:"node,omitempty"`
	Channels      []NodeChannelAPI     `json:"channels"`
	NumChannels   uint32               `json:"num_channels"`
	TotalCapacity uint64               `json:"total_capacity"`
}

// NodeChannelAPIExtended struct.
type NodeChannelAPIExtended struct {
	Private bool `json:"private,omitempty"`
	NodeChannelAPI
}

// NodeInfoAPIExtended struct.
type NodeInfoAPIExtended struct {
	NodeInfoAPI
	Channels []NodeChannelAPIExtended `json:"channels"`
}

////////////////////////////////////////////////////////////////

// Pagination struct.
type Pagination struct {
	Offset    uint64 // Exclusive thus 1 means start from 2 (0 will start from beginning)
	BatchSize uint64 // limit is 10k or so
	Reversed  bool
	From      *time.Time
	To        *time.Time
}

// PaymentStatus enum.
type PaymentStatus int

// PaymentStatus values.
const (
	PaymentUnknown PaymentStatus = iota
	PaymentInFlight
	PaymentSucceeded
	PaymentFailed
)

// StringToPaymentStatus creates PaymentStatus based on a string.
func StringToPaymentStatus(in string) PaymentStatus {
	switch strings.ToLower(in) {
	case "unknown":
		return PaymentUnknown
	case "in_flight":
		return PaymentInFlight
	case "succeeded":
		return PaymentSucceeded
	case "failed":
		return PaymentFailed
	}

	return PaymentUnknown
}

// PaymentFailureReason enum.
type PaymentFailureReason int

// PaymentFailureReason values.
const (
	FailureReasonNone PaymentFailureReason = 0
	FailureReasonTimeout
	FailureReasonNoRoute
	FailureReasonError
	FailureReasonIncorrectPaymentDetails
	FailureReasonInsufficientBalance
)

// HTLCStatus enum.
type HTLCStatus int

// HTLCStatus values.
const (
	HTLCInFlight HTLCStatus = 0
	HTLCSucceeded
	HTLCFailed
)

// Payment struct.
type Payment struct {
	PaymentHash     string
	ValueMsat       int64
	FeeMsat         int64
	PaymentPreimage string
	PaymentRequest  string
	PaymentStatus   PaymentStatus
	CreationTime    time.Time
	Index           uint64
	FailureReason   PaymentFailureReason
	HTLCAttempts    []HTLCAttempt
}

// HTLCAttempt struct.
type HTLCAttempt struct {
	ID      uint64
	Status  HTLCStatus
	Attempt time.Time
	Resolve time.Time

	Route Route
}

// Route struct.
type Route struct {
	TotalTimeLock uint32
	TotalFeesMsat int64
	TotalAmtMsat  int64

	Hops []Hop
}

// Hop struct.
type Hop struct {
	ChanID           uint64
	Expiry           uint32
	AmtToForwardMsat int64
	FeeMsat          int64
}

// ForwardingEvent struct.
type ForwardingEvent struct {
	Timestamp     time.Time
	ChanIDIn      uint64
	ChanIDOut     uint64
	AmountInMsat  uint64
	AmountOutMsat uint64
	FeeMsat       uint64
	IsSuccess     bool
	FailureString string
}

// ResponseForwardPagination struct.
type ResponseForwardPagination struct {
	LastOffsetIndex uint64
}

// ResponsePagination struct.
type ResponsePagination struct {
	ResponseForwardPagination
	FirstOffsetIndex uint64
}

// InvoicesResponse struct.
type InvoicesResponse struct {
	Invoices []Invoice
	ResponsePagination
}

// Invoice struct.
type Invoice struct {
	Memo            string
	ValueMsat       int64
	PaidMsat        int64
	CreationDate    time.Time
	SettleDate      time.Time
	PaymentRequest  string
	DescriptionHash string
	Expiry          int64
	FallbackAddr    string
	CltvExpiry      uint64
	Private         bool
	IsKeySend       bool
	IsAmp           bool
	State           InvoiceHTLCState
	AddIndex        uint64
	SettleIndex     uint64
}

// InvoiceHTLCState enum.
type InvoiceHTLCState int

// StringToInvoiceHTLCState creates InvoiceHTLCState based on a string.
func StringToInvoiceHTLCState(in string) InvoiceHTLCState {
	switch strings.ToLower(in) {
	case "accepted":
		return InvoiceAccepted
	case "settled":
		return InvoiceSettled
	case "cacelled":
		return InvoiceCancelled
	}

	return InvoiceCancelled
}

// InvoiceHTLCState values.
const (
	InvoiceAccepted InvoiceHTLCState = 0
	InvoiceSettled
	InvoiceCancelled
)

// PaymentsResponse struct.
type PaymentsResponse struct {
	Payments []Payment
	ResponsePagination
}

// RawMessage struct.
type RawMessage struct {
	Timestamp      time.Time       `json:"timestamp"`
	Implementation string          `json:"implementation,omitempty"`
	Message        json.RawMessage `json:"message,omitempty"`
}

// ResponseRawPagination struct.
type ResponseRawPagination struct {
	UseTimestamp bool
	FirstTime    time.Time
	LastTime     time.Time
	ResponsePagination
}

// RawPagination struct.
type RawPagination struct {
	UseTimestamp bool
	FirstTime    time.Time
	LastTime     time.Time
	Pagination
}

// Funds struct.
type Funds struct {
	TotalBalance     int64
	ConfirmedBalance int64
	LockedBalance    int64
}

// PaymentStatusEnum basic enum.
type PaymentStatusEnum int

// PaymentStatusEnum enum.
const (
	Failed PaymentStatusEnum = iota
	Pending
	Success
)

// PaymentResp struct.
type PaymentResp struct {
	Hash     string
	Preimage string
	Status   PaymentStatusEnum
}

// InvoiceResp struct.
type InvoiceResp struct {
	Hash           string
	PaymentRequest string
}

// Urgency of the on-chain sending
type Urgency int

// Urgency enum.
const (
	Low Urgency = iota
	Normal
	Urgent
)

// CommonInitiator enum.
type CommonInitiator string

const (
	Unknown CommonInitiator = "unknown"
	Local   CommonInitiator = "local"
	Remote  CommonInitiator = "remote"
)

// Close type enum.
type CommonCloseType string

const (
	UnknownType     CommonCloseType = "unknown"
	CooperativeType CommonCloseType = "cooperative"
	ForceType       CommonCloseType = "force"
)

// Close info struct.
type CloseInfo struct {
	ChanID    uint64          `json:"channel_id,omitempty"`
	Opener    CommonInitiator `json:"opener"`
	Closer    CommonInitiator `json:"closer"`
	CloseType CommonCloseType `json:"close_type"`
}

var UnknownCloseInfo = CloseInfo{ChanID: 0, Opener: Unknown, Closer: Unknown, CloseType: UnknownType}

////////////////////////////////////////////////////////////////

// API - generic API settings.
type API struct {
	Name                                  string
	GetNodeInfoFullThreshUseDescribeGraph int // If node has more than that number of channels use DescribeGraph else do GetChanInfo for each one
}

// GetDefaultBatchSize returns the default batch size.
func (a *API) GetDefaultBatchSize() uint16 {
	return 50
}

// GetNodeInfoFull - GetNodeInfoFull API (GRPC interface).
func (l *LndGrpcLightningAPI) GetNodeInfoFull(ctx context.Context, channels, unnanounced bool) (*NodeInfoAPIExtended, error) {
	return getNodeInfoFullTemplate(ctx, l, l.GetNodeInfoFullThreshUseDescribeGraph, channels, unnanounced)
}

// GetNodeInfoFull - GetNodeInfoFull API (REST interface).
func (l *LndRestLightningAPI) GetNodeInfoFull(ctx context.Context, channels, unnanounced bool) (*NodeInfoAPIExtended, error) {
	return getNodeInfoFullTemplate(ctx, l, l.GetNodeInfoFullThreshUseDescribeGraph, channels, unnanounced)
}

// getNodeInfoFullTemplate returns info for local node possibly including unnanounced channels (as soon as that can be obtained via GetNodeInfo this method is useless).
func getNodeInfoFullTemplate(ctx context.Context, l LightingAPICalls, threshUseDescribeGraph int, channels, unnanounced bool) (*NodeInfoAPIExtended, error) {
	info, err := l.GetInfo(ctx)
	if err != nil {
		return nil, err
	}

	nodeInfo, err := l.GetNodeInfo(ctx, info.IdentityPubkey, channels)
	if err != nil {
		return nil, err
	}

	extendedNodeInfo := &NodeInfoAPIExtended{NodeInfoAPI: *nodeInfo}

	if !unnanounced {
		// We have full info already (fast bailout)

		capacity := uint64(0)
		all := make([]NodeChannelAPIExtended, 0)
		for _, ch := range nodeInfo.Channels {
			all = append(all, NodeChannelAPIExtended{NodeChannelAPI: ch, Private: false})
			capacity += ch.Capacity
		}

		extendedNodeInfo.Channels = all
		extendedNodeInfo.NumChannels = uint32(len(all))
		extendedNodeInfo.TotalCapacity = capacity

		return extendedNodeInfo, err
	}

	// Else the channel stats are wrong (unnanounced channels did not count)
	chans, err := l.GetChannels(ctx)
	if err != nil {
		// TODO: Bit of a hack but nodeInfo is pretty much correct
		return extendedNodeInfo, err
	}

	numChans := 0
	totalCapacity := uint64(0)

	privateMapping := make(map[uint64]bool)

	for _, ch := range chans.Channels {
		if ch.Private && !unnanounced {
			continue
		}

		privateMapping[ch.ChanID] = ch.Private
		totalCapacity += ch.Capacity
		numChans++
	}

	extendedNodeInfo.NumChannels = uint32(numChans)
	extendedNodeInfo.TotalCapacity = totalCapacity

	if !channels {
		return extendedNodeInfo, nil
	}

	extendedNodeInfo.Channels = make([]NodeChannelAPIExtended, 0)

	if len(chans.Channels) <= threshUseDescribeGraph {
		for _, ch := range chans.Channels {
			if ch.Private && !unnanounced {
				continue
			}
			c, err := l.GetChanInfo(ctx, ch.ChanID)
			if err != nil {
				glog.Warningf("Could not get channel info for %v (%v): %v", ch.ChanID, info.IdentityPubkey, err)
				extendedNodeInfo.NumChannels--
				continue
			}
			private, ok := privateMapping[ch.ChanID]
			extendedNodeInfo.Channels = append(extendedNodeInfo.Channels, NodeChannelAPIExtended{NodeChannelAPI: *c, Private: ok && private})
		}
	} else {
		graph, err := l.DescribeGraph(ctx, unnanounced)
		if err != nil {
			// This could happen due to too big response (btcpay example with limited nginx), retry with other mode
			return getNodeInfoFullTemplate(ctx, l, math.MaxInt, channels, unnanounced)
		}
		for _, one := range graph.Channels {
			if one.Node1Pub != info.IdentityPubkey && one.Node2Pub != info.IdentityPubkey {
				continue
			}
			// No need to filter private channels (since we used unnanounced in DescribeGraph)
			private, ok := privateMapping[one.ChannelID]
			extendedNodeInfo.Channels = append(extendedNodeInfo.Channels, NodeChannelAPIExtended{NodeChannelAPI: one, Private: ok && private})
		}
	}

	return extendedNodeInfo, nil
}

// ErrorData struct.
type ErrorData struct {
	Error          error
	IsStillRunning bool
}

// RouteElement struct.
type RouteElement struct {
	PubKey            string
	OutgoingChannelId uint64
}

// Route alias.
type DeterminedRoute []RouteElement

// ExclusionBase struct.
type ExclusionBase struct {
}

// ExcludedNode struct.
type ExcludedNode struct {
	PubKey string
	ExclusionBase
}

// ExcludedEdge struct.
type ExcludedEdge struct {
	ChannelId uint64
	ExclusionBase
}

// Exclusion interface.
type Exclusion interface {
	IsNodeExclusion() bool
}

// IsNodeExclusion for edge
func (e ExcludedEdge) IsNodeExclusion() bool {
	return false
}

// IsNodeExclusion for node
func (e ExcludedNode) IsNodeExclusion() bool {
	return true
}

// OptimizeRouteFor enum.
type OptimizeRouteFor int

// OptimizeRouteFor values.
const (
	Reliability OptimizeRouteFor = iota
	Price
	None
)

// LightingAPICalls is the interface for lightning API.
type LightingAPICalls interface {
	Cleanup()
	GetAPIType() APIType
	GetInfo(ctx context.Context) (*InfoAPI, error)
	GetChannels(ctx context.Context) (*ChannelsAPI, error)
	DescribeGraph(ctx context.Context, unannounced bool) (*DescribeGraphAPI, error)
	GetNodeInfoFull(ctx context.Context, channels, unannounced bool) (*NodeInfoAPIExtended, error)
	GetNodeInfo(ctx context.Context, pubKey string, channels bool) (*NodeInfoAPI, error)
	GetChanInfo(ctx context.Context, chanID uint64) (*NodeChannelAPI, error)

	GetInvoices(ctx context.Context, pendingOnly bool, pagination Pagination) (*InvoicesResponse, error)
	GetPayments(ctx context.Context, includeIncomplete bool, pagination Pagination) (*PaymentsResponse, error)

	SubscribeForwards(ctx context.Context, since time.Time, batchSize uint16, maxErrors uint16) (<-chan []ForwardingEvent, <-chan ErrorData)

	GetInvoicesRaw(ctx context.Context, pendingOnly bool, pagination RawPagination) ([]RawMessage, *ResponseRawPagination, error)
	GetPaymentsRaw(ctx context.Context, includeIncomplete bool, pagination RawPagination) ([]RawMessage, *ResponseRawPagination, error)
	GetForwardsRaw(ctx context.Context, pagination RawPagination) ([]RawMessage, *ResponseRawPagination, error)

	ConnectPeer(ctx context.Context, id string) error
	GetOnChainAddress(ctx context.Context) (string, error)
	GetOnChainFunds(ctx context.Context) (*Funds, error)
	SendToOnChainAddress(ctx context.Context, address string, sats int64, useUnconfirmed bool, urgency Urgency) (string, error)
	PayInvoice(ctx context.Context, paymentRequest string, sats int64, outgoingChanIds []uint64) (*PaymentResp, error)
	GetPaymentStatus(ctx context.Context, paymentRequest string) (*PaymentResp, error)
	CreateInvoice(ctx context.Context, sats int64, preimage string, memo string, expiry time.Duration) (*InvoiceResp, error)
	IsInvoicePaid(ctx context.Context, paymentHash string) (bool, error)

	GetChannelCloseInfo(ctx context.Context, chanIDs []uint64) ([]CloseInfo, error)

	// Includes source but NOT destination addreses in response
	GetRoute(ctx context.Context, source string, destination string, exclusions []Exclusion, optimizeFor OptimizeRouteFor, msats int64) (DeterminedRoute, error)
	GetRoutes(ctx context.Context, source string, destination string, exclusions []Exclusion, optimizeFor OptimizeRouteFor, msats int64) (<-chan DeterminedRoute, error)
}

// GetDataCall - signature of function for retrieving data.
type GetDataCall func() (*entities.Data, error)

// NewAPI - gets new lightning API.
func NewAPI(apiType APIType, getData GetDataCall) (LightingAPICalls, error) {
	if getData == nil {
		sentry.CaptureMessage("getData was nil")
		return nil, fmt.Errorf("getData error")
	}

	data, err := getData()
	if err != nil {
		sentry.CaptureException(err)
		return nil, err
	}

	t := LndGrpc

	if data.ApiType != nil {
		foo, err := GetAPIType(data.ApiType)
		if err != nil {
			t = LndGrpc
		} else {
			t = *foo
		}
	} else {
		t = apiType
	}

	switch t {
	case LndGrpc:
		return NewLndGrpcLightningAPI(getData), nil
	case LndRest:
		return NewLndRestLightningAPI(getData), nil
	case ClnSocket:
		return NewClnSocketLightningAPI(getData), nil
	case ClnCommando:
		return NewClnCommandoLightningAPI(getData), nil
	}

	sentry.CaptureMessage("Invalid api type")
	return nil, fmt.Errorf("invalid API type")
}