1  package invoices
  2  
  3  import (
  4  	"time"
  5  
  6  	"github.com/lightningnetwork/lnd/lntypes"
  7  )
  8  
  9  // HtlcResolution describes how an htlc should be resolved.
 10  type HtlcResolution interface {
 11  	// CircuitKey returns the circuit key for the htlc that we have a
 12  	// resolution for.
 13  	CircuitKey() CircuitKey
 14  }
 15  
 16  // HtlcFailResolution is an implementation of the HtlcResolution interface
 17  // which is returned when a htlc is failed.
 18  type HtlcFailResolution struct {
 19  	// circuitKey is the key of the htlc for which we have a resolution.
 20  	circuitKey CircuitKey
 21  
 22  	// AcceptHeight is the original height at which the htlc was accepted.
 23  	AcceptHeight int32
 24  
 25  	// Outcome indicates the outcome of the invoice registry update.
 26  	Outcome FailResolutionResult
 27  }
 28  
 29  // NewFailResolution returns a htlc failure resolution.
 30  func NewFailResolution(key CircuitKey, acceptHeight int32,
 31  	outcome FailResolutionResult) *HtlcFailResolution {
 32  
 33  	return &HtlcFailResolution{
 34  		circuitKey:   key,
 35  		AcceptHeight: acceptHeight,
 36  		Outcome:      outcome,
 37  	}
 38  }
 39  
 40  // CircuitKey returns the circuit key for the htlc that we have a
 41  // resolution for.
 42  //
 43  // Note: it is part of the HtlcResolution interface.
 44  func (f *HtlcFailResolution) CircuitKey() CircuitKey {
 45  	return f.circuitKey
 46  }
 47  
 48  // HtlcSettleResolution is an implementation of the HtlcResolution interface
 49  // which is returned when a htlc is settled.
 50  type HtlcSettleResolution struct {
 51  	// Preimage is the htlc preimage. Its value is nil in case of a cancel.
 52  	Preimage lntypes.Preimage
 53  
 54  	// circuitKey is the key of the htlc for which we have a resolution.
 55  	circuitKey CircuitKey
 56  
 57  	// acceptHeight is the original height at which the htlc was accepted.
 58  	AcceptHeight int32
 59  
 60  	// Outcome indicates the outcome of the invoice registry update.
 61  	Outcome SettleResolutionResult
 62  }
 63  
 64  // NewSettleResolution returns a htlc resolution which is associated with a
 65  // settle.
 66  func NewSettleResolution(preimage lntypes.Preimage, key CircuitKey,
 67  	acceptHeight int32,
 68  	outcome SettleResolutionResult) *HtlcSettleResolution {
 69  
 70  	return &HtlcSettleResolution{
 71  		Preimage:     preimage,
 72  		circuitKey:   key,
 73  		AcceptHeight: acceptHeight,
 74  		Outcome:      outcome,
 75  	}
 76  }
 77  
 78  // CircuitKey returns the circuit key for the htlc that we have a
 79  // resolution for.
 80  //
 81  // Note: it is part of the HtlcResolution interface.
 82  func (s *HtlcSettleResolution) CircuitKey() CircuitKey {
 83  	return s.circuitKey
 84  }
 85  
 86  // htlcAcceptResolution is an implementation of the HtlcResolution interface
 87  // which is returned when a htlc is accepted. This struct is not exported
 88  // because the codebase uses a nil resolution to indicate that a htlc was
 89  // accepted. This struct is used internally in the invoice registry to
 90  // surface accept resolution results. When an invoice update returns an
 91  // acceptResolution, a nil resolution should be surfaced.
 92  type htlcAcceptResolution struct {
 93  	// circuitKey is the key of the htlc for which we have a resolution.
 94  	circuitKey CircuitKey
 95  
 96  	// autoRelease signals that the htlc should be automatically released
 97  	// after a timeout.
 98  	autoRelease bool
 99  
100  	// acceptTime is the time at which this htlc was accepted.
101  	acceptTime time.Time
102  
103  	// outcome indicates the outcome of the invoice registry update.
104  	outcome acceptResolutionResult
105  }
106  
107  // newAcceptResolution returns a htlc resolution which is associated with a
108  // htlc accept.
109  func newAcceptResolution(key CircuitKey,
110  	outcome acceptResolutionResult) *htlcAcceptResolution {
111  
112  	return &htlcAcceptResolution{
113  		circuitKey: key,
114  		outcome:    outcome,
115  	}
116  }
117  
118  // CircuitKey returns the circuit key for the htlc that we have a
119  // resolution for.
120  //
121  // Note: it is part of the HtlcResolution interface.
122  func (a *htlcAcceptResolution) CircuitKey() CircuitKey {
123  	return a.circuitKey
124  }