multi: move FeeSchedule to terms package

As a preparation to avoid package import cycles when introducing more
generic terms, we move the FeeSchedule interface and its
LinearFeeSchedule implementation to the terms package.

auctioneer/client.go

@@ -18,6 +18,7 @@ import (
 	"github.com/lightninglabs/llm/account"
 	"github.com/lightninglabs/llm/clmrpc"
 	"github.com/lightninglabs/llm/order"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightninglabs/lndclient"
 	"github.com/lightningnetwork/lnd/keychain"
 	"google.golang.org/grpc"
@@ -1090,13 +1091,13 @@ func unmarshallServerAccount(keyDesc *keychain.KeyDescriptor,
 }
 
 // FeeQuote returns the current fee schedule for the auction.
-func (c *Client) FeeQuote(ctx context.Context) (*order.LinearFeeSchedule, error) {
+func (c *Client) FeeQuote(ctx context.Context) (*terms.LinearFeeSchedule, error) {
 	resp, err := c.client.FeeQuote(ctx, &clmrpc.FeeQuoteRequest{})
 	if err != nil {
 		return nil, err
 	}
 
-	return order.NewLinearFeeSchedule(
+	return terms.NewLinearFeeSchedule(
 		btcutil.Amount(resp.ExecutionFee.BaseFee),
 		btcutil.Amount(resp.ExecutionFee.FeeRate),
 	), nil

cmd/llm/order.go

@@ -11,6 +11,7 @@ import (
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/llm/clmrpc"
 	"github.com/lightninglabs/llm/order"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 	"github.com/urfave/cli"
 )
@@ -263,7 +264,7 @@ func printOrderDetails(client clmrpc.TraderClient, amt btcutil.Amount,
 		return err
 	}
 
-	feeSchedule := order.NewLinearFeeSchedule(
+	feeSchedule := terms.NewLinearFeeSchedule(
 		btcutil.Amount(auctionFee.ExecutionFee.BaseFee),
 		btcutil.Amount(auctionFee.ExecutionFee.FeeRate),
 	)

order/batch.go

@@ -11,6 +11,7 @@ import (
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/llm/account"
 	"github.com/lightninglabs/llm/clmrpc"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 )
@@ -157,7 +158,7 @@ type Batch struct {
 
 	// ExecutionFee is the FeeSchedule that was used by the server to
 	// calculate the execution fee.
-	ExecutionFee FeeSchedule
+	ExecutionFee terms.FeeSchedule
 
 	// ClearingPrice is the fixed rate the orders were cleared at.
 	ClearingPrice FixedRatePremium

order/batch_verifier.go

@@ -10,6 +10,7 @@ import (
 	"github.com/btcsuite/btcd/btcec"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightninglabs/llm/account"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightninglabs/lndclient"
 	"github.com/lightningnetwork/lnd/input"
 )
@@ -213,7 +214,7 @@ func (v *batchVerifier) Verify(batch *Batch) error {
 // validateMatchedOrder validates our order against another trader's order and
 // tallies up our order's account balance.
 func (v *batchVerifier) validateMatchedOrder(tally *AccountTally,
-	ourOrder Order, otherOrder *MatchedOrder, executionFee FeeSchedule,
+	ourOrder Order, otherOrder *MatchedOrder, executionFee terms.FeeSchedule,
 	clearingPrice FixedRatePremium) error {
 
 	// Order type must be opposite.

order/batch_verifier_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/lightninglabs/llm/account"
 	"github.com/lightninglabs/llm/clmrpc"
 	"github.com/lightninglabs/llm/internal/test"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -198,7 +199,7 @@ func TestBatchVerifier(t *testing.T) {
 			doVerify: func(v BatchVerifier, a *Ask, b1, b2 *Bid,
 				b *Batch) error {
 
-				b.ExecutionFee = NewLinearFeeSchedule(1, 1)
+				b.ExecutionFee = terms.NewLinearFeeSchedule(1, 1)
 				return v.Verify(b)
 			},
 		},
@@ -208,7 +209,7 @@ func TestBatchVerifier(t *testing.T) {
 			doVerify: func(v BatchVerifier, a *Ask, b1, b2 *Bid,
 				b *Batch) error {
 
-				b.ExecutionFee = NewLinearFeeSchedule(0, 0)
+				b.ExecutionFee = terms.NewLinearFeeSchedule(0, 0)
 				b.BatchTX.TxOut[2].Value += 2220
 				b.AccountDiffs[0].EndingBalance += 2220
 				b.AccountDiffs[1].EndingBalance += 2220
@@ -221,7 +222,7 @@ func TestBatchVerifier(t *testing.T) {
 			doVerify: func(v BatchVerifier, a *Ask, b1, b2 *Bid,
 				b *Batch) error {
 
-				b.ExecutionFee = NewLinearFeeSchedule(0, 0)
+				b.ExecutionFee = terms.NewLinearFeeSchedule(0, 0)
 				b.BatchTX.TxOut[2].Value += 2220
 				b.AccountDiffs[0].EndingBalance += 2220
 				b.AccountDiffs[1].EndingBalance += 2220
@@ -401,7 +402,7 @@ func TestBatchVerifier(t *testing.T) {
 			Version:       DefaultVersion,
 			MatchedOrders: matchedOrders,
 			AccountDiffs:  accountDiffs,
-			ExecutionFee: NewLinearFeeSchedule(
+			ExecutionFee: terms.NewLinearFeeSchedule(
 				execFeeBase, execFeeRate,
 			),
 			ClearingPrice:  clearingPrice,

order/interface.go

@@ -12,6 +12,7 @@ import (
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/llm/account"
 	"github.com/lightninglabs/llm/clmrpc"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -168,7 +169,7 @@ type Order interface {
 	// ReservedValue returns the maximum value that could be deducted from
 	// the account if the order is is matched, and therefore has to be
 	// reserved to ensure the trader can afford it.
-	ReservedValue(feeSchedule FeeSchedule) btcutil.Amount
+	ReservedValue(feeSchedule terms.FeeSchedule) btcutil.Amount
 }
 
 // Kit stores all the common fields that are used to express the decision to
@@ -347,7 +348,7 @@ func reservedValue(o Order,
 
 // ReservedValue returns the maximum value that could be deducted from a single
 // account if the ask is is matched under the worst case fee conditions.
-func (a *Ask) ReservedValue(feeSchedule FeeSchedule) btcutil.Amount {
+func (a *Ask) ReservedValue(feeSchedule terms.FeeSchedule) btcutil.Amount {
 	// For an ask the clearing price will be no lower than the ask's fixed
 	// rate, resulting in the smallest gain for the asker.
 	clearingPrice := FixedRatePremium(a.FixedRate)
@@ -410,7 +411,7 @@ func (b *Bid) Digest() ([sha256.Size]byte, error) {
 
 // ReservedValue returns the maximum value that could be deducted from a single
 // account if the bid is is matched under the worst case fee conditions.
-func (b *Bid) ReservedValue(feeSchedule FeeSchedule) btcutil.Amount {
+func (b *Bid) ReservedValue(feeSchedule terms.FeeSchedule) btcutil.Amount {
 	// For a bid, the final clearing price is never higher
 	// that the bid's fixed rate, resulting in the highest possible
 	// premium paid bu the bidder.

order/interface_test.go

@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/btcsuite/btcutil"
+	"github.com/lightninglabs/llm/terms"
 )
 
 // TestOrderReservedValue checks orders' ReservedValue merhod returning the
@@ -11,7 +12,7 @@ import (
 func TestOrderReservedValue(t *testing.T) {
 	t.Parallel()
 
-	simpleFeeSchedule := NewLinearFeeSchedule(1, 100)
+	simpleFeeSchedule := terms.NewLinearFeeSchedule(1, 100)
 
 	testCases := []struct {
 		name  string

order/manager.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/lightninglabs/llm/account"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightninglabs/lndclient"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -122,7 +123,7 @@ func (m *Manager) Stop() {
 
 // PrepareOrder validates an order, signs it and then stores it locally.
 func (m *Manager) PrepareOrder(ctx context.Context, order Order,
-	acct *account.Account, feeSchedule FeeSchedule) (
+	acct *account.Account, feeSchedule terms.FeeSchedule) (
 	*ServerOrderParams, error) {
 
 	// Verify incoming request for formal validity.
@@ -195,7 +196,7 @@ func (m *Manager) PrepareOrder(ctx context.Context, order Order,
 // validateOrder makes sure an order is formally correct and that the associated
 // account contains enough balance to execute the order.
 func (m *Manager) validateOrder(order Order, acct *account.Account,
-	feeSchedule FeeSchedule) error {
+	feeSchedule terms.FeeSchedule) error {
 
 	// First parse order type specific fields.
 	switch o := order.(type) {

order/manager_test.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/llm/account"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/keychain"
 )
 
@@ -49,7 +50,7 @@ func TestValidateOrderAccountIsolation(t *testing.T) {
 		MaxDuration: 144,
 	}
 
-	simpleFeeSchedule := NewLinearFeeSchedule(1, 100)
+	simpleFeeSchedule := terms.NewLinearFeeSchedule(1, 100)
 
 	// Submitting this order for account B should pass validation.
 	err := orderManager.validateOrder(

order/rpc_parse.go

@@ -11,6 +11,7 @@ import (
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
 	"github.com/lightninglabs/llm/clmrpc"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 )
@@ -218,7 +219,7 @@ func ParseRPCBatch(prepareMsg *clmrpc.OrderMatchPrepare) (*Batch,
 	if prepareMsg.ExecutionFee == nil {
 		return nil, fmt.Errorf("execution fee missing")
 	}
-	b.ExecutionFee = NewLinearFeeSchedule(
+	b.ExecutionFee = terms.NewLinearFeeSchedule(
 		btcutil.Amount(prepareMsg.ExecutionFee.BaseFee),
 		btcutil.Amount(prepareMsg.ExecutionFee.FeeRate),
 	)

order/tradingfees.go

@@ -5,6 +5,7 @@ import (
 	"github.com/btcsuite/btcutil"
 	"github.com/btcsuite/btcwallet/wallet/txrules"
 	"github.com/lightninglabs/llm/clmscript"
+	"github.com/lightninglabs/llm/terms"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
 )
@@ -54,60 +55,6 @@ func (f FixedRatePremium) LumpSumPremium(amt btcutil.Amount,
 	return btcutil.Amount(premiumPerBlock * float64(durationBlocks))
 }
 
-// FeeSchedule is an interface that represents the configuration source that
-// the auctioneer will use to determine how much to charge in fees for each
-// trader.
-type FeeSchedule interface {
-	// BaseFee is the base fee the auctioneer will charge the traders for
-	// each executed order.
-	BaseFee() btcutil.Amount
-
-	// ExecutionFee computes the execution fee (usually based off of a
-	// rate) for the target amount.
-	ExecutionFee(amt btcutil.Amount) btcutil.Amount
-}
-
-// LinearFeeSchedule is a FeeSchedule that calculates the execution fee based
-// upon a static base fee and a variable fee rate in parts per million.
-type LinearFeeSchedule struct {
-	baseFee btcutil.Amount
-	feeRate btcutil.Amount
-}
-
-// BaseFee is the base fee the auctioneer will charge the traders for each
-// executed order.
-//
-// NOTE: This method is part of the orderT.FeeSchedule interface.
-func (s *LinearFeeSchedule) BaseFee() btcutil.Amount {
-	return s.baseFee
-}
-
-// FeeRate is the variable fee rate in parts per million.
-func (s *LinearFeeSchedule) FeeRate() btcutil.Amount {
-	return s.feeRate
-}
-
-// ExecutionFee computes the execution fee (usually based off of a rate) for
-// the target amount.
-//
-// NOTE: This method is part of the orderT.FeeSchedule interface.
-func (s *LinearFeeSchedule) ExecutionFee(amt btcutil.Amount) btcutil.Amount {
-	return amt * s.feeRate / 1_000_000
-}
-
-// NewLinearFeeSchedule creates a new linear fee schedule based upon a static
-// base fee and a relative fee rate in parts per million.
-func NewLinearFeeSchedule(baseFee, feeRate btcutil.Amount) *LinearFeeSchedule {
-	return &LinearFeeSchedule{
-		baseFee: baseFee,
-		feeRate: feeRate,
-	}
-}
-
-// This is a compile time check to make certain that LinearFeeSchedule
-// implements the orderT.FeeSchedule interface.
-var _ FeeSchedule = (*LinearFeeSchedule)(nil)
-
 // PerBlockPremium calculates the absolute premium in fractions of satoshis for
 // a one block duration from the amount and the specified fee rate in parts per
 // million.
@@ -175,7 +122,7 @@ type AccountTally struct {
 // makerDelta calculates an account's balance and fee difference for a single
 // order where the account is involved on the maker side. It returns the
 // balance delta, fees accrued, and execution fee paid.
-func makerDelta(feeSchedule FeeSchedule, price FixedRatePremium,
+func makerDelta(feeSchedule terms.FeeSchedule, price FixedRatePremium,
 	totalSats btcutil.Amount, duration uint32) (btcutil.Amount,
 	btcutil.Amount, btcutil.Amount) {
 
@@ -201,7 +148,7 @@ func makerDelta(feeSchedule FeeSchedule, price FixedRatePremium,
 // CalcMakerDelta calculates an account's balance and fee difference for a
 // single order where the account is involved on the maker side. It returns the
 // execution fee that is collected by the auctioneer.
-func (t *AccountTally) CalcMakerDelta(feeSchedule FeeSchedule,
+func (t *AccountTally) CalcMakerDelta(feeSchedule terms.FeeSchedule,
 	price FixedRatePremium, totalSats btcutil.Amount,
 	duration uint32) btcutil.Amount {
 
@@ -220,7 +167,7 @@ func (t *AccountTally) CalcMakerDelta(feeSchedule FeeSchedule,
 // takerDelta calculates an account's balance and fee difference for a single
 // order where the account is involved on the taker side. It returns the
 // balance delta, taker fees paid, and execution fee paid.
-func takerDelta(feeSchedule FeeSchedule,
+func takerDelta(feeSchedule terms.FeeSchedule,
 	price FixedRatePremium, totalSats btcutil.Amount,
 	duration uint32) (btcutil.Amount, btcutil.Amount, btcutil.Amount) {
 
@@ -242,7 +189,7 @@ func takerDelta(feeSchedule FeeSchedule,
 // CalcTakerDelta calculates an account's balance and fee difference for a
 // single order where the account is involved on the taker side. It returns the
 // execution fee that is collected by the auctioneer.
-func (t *AccountTally) CalcTakerDelta(feeSchedule FeeSchedule,
+func (t *AccountTally) CalcTakerDelta(feeSchedule terms.FeeSchedule,
 	price FixedRatePremium, totalSats btcutil.Amount,
 	duration uint32) btcutil.Amount {
 
@@ -286,6 +233,8 @@ func minNoDustAccountSize() btcutil.Amount {
 
 // executionFee calculates the execution fee which is the base fee plus the
 // execution fee which scales based on the order size.
-func executionFee(amount btcutil.Amount, schedule FeeSchedule) btcutil.Amount {
+func executionFee(amount btcutil.Amount,
+	schedule terms.FeeSchedule) btcutil.Amount {
+
 	return schedule.BaseFee() + schedule.ExecutionFee(amount)
 }

terms/fees.go

@@ -0,0 +1,57 @@
+package terms
+
+import "github.com/btcsuite/btcutil"
+
+// FeeSchedule is an interface that represents the configuration source that
+// the auctioneer will use to determine how much to charge in fees for each
+// trader.
+type FeeSchedule interface {
+	// BaseFee is the base fee the auctioneer will charge the traders for
+	// each executed order.
+	BaseFee() btcutil.Amount
+
+	// ExecutionFee computes the execution fee (usually based off of a
+	// rate) for the target amount.
+	ExecutionFee(amt btcutil.Amount) btcutil.Amount
+}
+
+// LinearFeeSchedule is a FeeSchedule that calculates the execution fee based
+// upon a static base fee and a variable fee rate in parts per million.
+type LinearFeeSchedule struct {
+	baseFee btcutil.Amount
+	feeRate btcutil.Amount
+}
+
+// BaseFee is the base fee the auctioneer will charge the traders for each
+// executed order.
+//
+// NOTE: This method is part of the orderT.FeeSchedule interface.
+func (s *LinearFeeSchedule) BaseFee() btcutil.Amount {
+	return s.baseFee
+}
+
+// FeeRate is the variable fee rate in parts per million.
+func (s *LinearFeeSchedule) FeeRate() btcutil.Amount {
+	return s.feeRate
+}
+
+// ExecutionFee computes the execution fee (usually based off of a rate) for
+// the target amount.
+//
+// NOTE: This method is part of the orderT.FeeSchedule interface.
+func (s *LinearFeeSchedule) ExecutionFee(amt btcutil.Amount) btcutil.Amount {
+	return amt * s.feeRate / 1_000_000
+}
+
+// NewLinearFeeSchedule creates a new linear fee schedule based upon a static
+// base fee and a relative fee rate in parts per million.
+func NewLinearFeeSchedule(baseFee, feeRate btcutil.Amount) *LinearFeeSchedule {
+	return &LinearFeeSchedule{
+		baseFee: baseFee,
+		feeRate: feeRate,
+	}
+}
+
+// This is a compile time check to make certain that LinearFeeSchedule
+// implements the orderT.FeeSchedule interface.
+var _ FeeSchedule = (*LinearFeeSchedule)(nil)