swap amount input

swap_amounts.go

@@ -0,0 +1,213 @@
+package pump_parser
+
+import (
+	"encoding/json"
+
+	"github.com/gagliardetto/solana-go"
+	"github.com/shopspring/decimal"
+)
+
+var maxSlippageBps = decimal.NewFromInt(10000)
+
+type SwapMode uint8
+type SwapAmountSide uint8
+type SwapLimitType uint8
+
+const (
+	SwapModeUnknown SwapMode = iota
+	SwapModeExactIn
+	SwapModeExactOut
+)
+
+const (
+	SwapAmountSideUnknown SwapAmountSide = iota
+	SwapAmountSideBase
+	SwapAmountSideQuote
+)
+
+const (
+	SwapLimitTypeUnknown SwapLimitType = iota
+	SwapLimitTypeMinOut
+	SwapLimitTypeMaxIn
+)
+
+func (m SwapMode) String() string {
+	switch m {
+	case SwapModeExactIn:
+		return "exact_in"
+	case SwapModeExactOut:
+		return "exact_out"
+	default:
+		return ""
+	}
+}
+
+func (m SwapMode) MarshalJSON() ([]byte, error) {
+	return json.Marshal(m.String())
+}
+
+func (s SwapAmountSide) String() string {
+	switch s {
+	case SwapAmountSideBase:
+		return "base"
+	case SwapAmountSideQuote:
+		return "quote"
+	default:
+		return ""
+	}
+}
+
+func (s SwapAmountSide) MarshalJSON() ([]byte, error) {
+	return json.Marshal(s.String())
+}
+
+func (t SwapLimitType) String() string {
+	switch t {
+	case SwapLimitTypeMinOut:
+		return "min_out"
+	case SwapLimitTypeMaxIn:
+		return "max_in"
+	default:
+		return ""
+	}
+}
+
+func (t SwapLimitType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(t.String())
+}
+
+func swapAmountForSide(baseAmount, quoteAmount decimal.Decimal, side SwapAmountSide) decimal.Decimal {
+	switch side {
+	case SwapAmountSideBase:
+		return baseAmount
+	case SwapAmountSideQuote:
+		return quoteAmount
+	default:
+		return decimal.Zero
+	}
+}
+
+func swapMintForSide(baseMint, quoteMint solana.PublicKey, side SwapAmountSide) solana.PublicKey {
+	switch side {
+	case SwapAmountSideBase:
+		return baseMint
+	case SwapAmountSideQuote:
+		return quoteMint
+	default:
+		return solana.PublicKey{}
+	}
+}
+
+func oppositeSwapAmountSide(side SwapAmountSide) SwapAmountSide {
+	switch side {
+	case SwapAmountSideBase:
+		return SwapAmountSideQuote
+	case SwapAmountSideQuote:
+		return SwapAmountSideBase
+	default:
+		return SwapAmountSideUnknown
+	}
+}
+
+func fixedSwapAmountSide(event string, swapMode SwapMode) SwapAmountSide {
+	switch swapMode {
+	case SwapModeExactIn:
+		switch event {
+		case TxEventBuy:
+			return SwapAmountSideQuote
+		case TxEventSell:
+			return SwapAmountSideBase
+		}
+	case SwapModeExactOut:
+		switch event {
+		case TxEventBuy:
+			return SwapAmountSideBase
+		case TxEventSell:
+			return SwapAmountSideQuote
+		}
+	}
+	return SwapAmountSideUnknown
+}
+
+func limitSwapAmountType(swapMode SwapMode) SwapLimitType {
+	switch swapMode {
+	case SwapModeExactIn:
+		return SwapLimitTypeMinOut
+	case SwapModeExactOut:
+		return SwapLimitTypeMaxIn
+	default:
+		return SwapLimitTypeUnknown
+	}
+}
+
+func calculateLimitSlippageBps(limitType SwapLimitType, limitAmount, actualAmount decimal.Decimal) decimal.Decimal {
+	switch limitType {
+	case SwapLimitTypeMinOut:
+		if !actualAmount.IsPositive() {
+			if !limitAmount.IsPositive() {
+				return maxSlippageBps
+			}
+			return maxSlippageBps.Neg()
+		}
+		if !limitAmount.IsPositive() {
+			return maxSlippageBps
+		}
+		return actualAmount.Sub(limitAmount).Mul(maxSlippageBps).Div(actualAmount)
+	case SwapLimitTypeMaxIn:
+		if !limitAmount.IsPositive() {
+			if !actualAmount.IsPositive() {
+				return maxSlippageBps
+			}
+			return maxSlippageBps.Neg()
+		}
+		return limitAmount.Sub(actualAmount).Mul(maxSlippageBps).Div(limitAmount)
+	default:
+		return decimal.Zero
+	}
+}
+
+func (s *Swap) SetSwapAmountInfoDetailed(
+	swapMode SwapMode,
+	fixedAmount decimal.Decimal,
+	fixedSide SwapAmountSide,
+	fixedMint solana.PublicKey,
+	limitType SwapLimitType,
+	limitAmount decimal.Decimal,
+	limitSide SwapAmountSide,
+	limitMint solana.PublicKey,
+	actualLimitAmount decimal.Decimal,
+) {
+	s.SwapMode = swapMode
+	s.FixedAmount = fixedAmount
+	s.FixedAmountSide = fixedSide
+	s.FixedMint = fixedMint
+	s.LimitAmountType = limitType
+	s.LimitAmount = limitAmount
+	s.LimitAmountSide = limitSide
+	s.LimitMint = limitMint
+	s.ActualLimitAmount = actualLimitAmount
+	s.ActualLimitAmountSide = limitSide
+	s.SlippageBps = calculateLimitSlippageBps(limitType, limitAmount, actualLimitAmount)
+}
+
+func (s *Swap) SetSwapAmountInfo(swapMode SwapMode, fixedAmount, limitAmount decimal.Decimal) {
+	fixedSide := fixedSwapAmountSide(s.Event, swapMode)
+	if fixedSide == SwapAmountSideUnknown {
+		return
+	}
+
+	limitType := limitSwapAmountType(swapMode)
+	limitSide := oppositeSwapAmountSide(fixedSide)
+	actualLimitAmount := swapAmountForSide(s.BaseAmount, s.QuoteAmount, limitSide)
+	s.SetSwapAmountInfoDetailed(
+		swapMode,
+		fixedAmount,
+		fixedSide,
+		swapMintForSide(s.BaseMint, s.QuoteMint, fixedSide),
+		limitType,
+		limitAmount,
+		limitSide,
+		swapMintForSide(s.BaseMint, s.QuoteMint, limitSide),
+		actualLimitAmount,
+	)
+}