package shreder

import (
	"encoding/binary"
	"fmt"

	"github.com/gagliardetto/solana-go"
	"github.com/near/borsh-go"
	"github.com/shopspring/decimal"
)

var qtkvProgramID = solana.MustPublicKeyFromBase58("qtkvapJEvRWWrB7i5K6RaA1kvq5x3qmMKZ98ad71XQ7")
var (
	qtkvBuyTokensIX     = []byte{0x02}
	qtkvSellTokensIX    = []byte{0x03}
	qtkvAmmSellTokensIX = []byte{0x05}
)

type qtkvBuyArgs struct {
	Placeholder uint64
	TokenNumber uint64
	SolAmount   uint64
}

func parseQtkvInstruction(tx VersionedTransaction, instructionIndex int) (TxSignalBatch, error) {
	if instructionIndex >= len(tx.Instructions) {
		return nil, fmt.Errorf("instruction index out of bounds")
	}

	instruction := tx.Instructions[instructionIndex]
	if len(instruction.Data) == 0 {
		return nil, fmt.Errorf("data is empty")
	}

	var (
		err      error
		txSignal *TxSignal
	)
	if matchMethod(instruction.Data, qtkvBuyTokensIX) {
		txSignal, err = parseQtkvBuy(tx, instructionIndex)
	} else if matchMethod(instruction.Data, qtkvAmmSellTokensIX) {
		txSignal, err = parseQtkvAmmSell(tx, instructionIndex)
	} else if matchMethod(instruction.Data, qtkvSellTokensIX) {
		txSignal, err = parseQtkvSell(tx, instructionIndex)
	}

	if txSignal != nil {
		return TxSignalBatch{txSignal}, err
	}

	return nil, err
}

func parseQtkvSell(tx VersionedTransaction, instructionIndex int) (*TxSignal, error) {
	instruction := tx.Instructions[instructionIndex]
	if len(instruction.Accounts) < 11 {
		return nil, fmt.Errorf("accounts too short")
	}
	if len(instruction.Data) < 24 {
		return nil, fmt.Errorf("data too short for qtkv sell args, len=%d", len(instruction.Data))
	}

	mint, err := tx.GetAccount(int(instruction.Accounts[10]))
	if err != nil {
		return nil, err
	}
	user, err := tx.GetAccount(int(instruction.Accounts[0]))
	if err != nil {
		return nil, err
	}

	// in sell, sol amount is not directly provided, so we set it to 0
	tokenAmount := binary.LittleEndian.Uint64(instruction.Data[19:25])
	return &TxSignal{
		TxHash:             tx.Signatures[0].String(),
		Label:              "qtkv",
		Maker:              user.String(),
		Token0Address:      mint.String(),
		Token1Address:      wsolMint,
		Token0Amount:       formatTokenAmount(tokenAmount),
		Token1Amount:       decimal.Zero,
		Program:            "Pump",
		Event:              "sell",
		IsToken2022:        false,
		IsMayhemMode:       false,
		Block:              tx.Block,
		Token0AmountUint64: tokenAmount,
		Token1AmountUint64: 0,
	}, nil
}

func parseQtkvAmmSell(tx VersionedTransaction, instructionIndex int) (*TxSignal, error) {
	instruction := tx.Instructions[instructionIndex]
	if len(instruction.Accounts) < 11 {
		return nil, fmt.Errorf("accounts too short")
	}
	if len(instruction.Data) < 24 {
		return nil, fmt.Errorf("data too short for qtkv amm sell args, len=%d", len(instruction.Data))
	}

	mint, err := tx.GetAccount(int(instruction.Accounts[10]))
	if err != nil {
		return nil, err
	}
	user, err := tx.GetAccount(int(instruction.Accounts[0]))
	if err != nil {
		return nil, err
	}

	// in sell, sol amount is not directly provided, so we set it to 0
	tokenAmount := binary.LittleEndian.Uint64(instruction.Data[19:25])
	return &TxSignal{
		TxHash:             tx.Signatures[0].String(),
		Label:              "qtkv",
		Maker:              user.String(),
		Token0Address:      mint.String(),
		Token1Address:      wsolMint,
		Token0Amount:       formatTokenAmount(tokenAmount),
		Token1Amount:       decimal.Zero,
		Program:            "PumpAMM",
		Event:              "sell",
		IsToken2022:        false,
		IsMayhemMode:       false,
		Block:              tx.Block,
		Token0AmountUint64: tokenAmount,
		Token1AmountUint64: 0,
	}, nil
}

func parseQtkvBuy(tx VersionedTransaction, instructionIndex int) (*TxSignal, error) {
	instruction := tx.Instructions[instructionIndex]
	if len(instruction.Accounts) < 8 {
		return nil, fmt.Errorf("accounts too short")
	}

	mint, err := tx.GetAccount(int(instruction.Accounts[3]))
	if err != nil {
		return nil, err
	}
	user, err := tx.GetAccount(int(instruction.Accounts[0]))
	if err != nil {
		return nil, err
	}

	var args qtkvBuyArgs
	if err := borsh.Deserialize(&args, instruction.Data[1:]); err != nil {
		return nil, fmt.Errorf("failed to parse buy tokens args: %w", err)
	}

	return &TxSignal{
		TxHash:             tx.Signatures[0].String(),
		Label:              "qtkv",
		Maker:              user.String(),
		Token0Address:      mint.String(),
		Token1Address:      wsolMint,
		Token0Amount:       formatTokenAmount(args.TokenNumber),
		Token1Amount:       formatSolAmount(args.SolAmount),
		Program:            "Pump",
		Event:              "buy",
		IsToken2022:        false,
		IsMayhemMode:       false,
		Block:              tx.Block,
		Token0AmountUint64: args.TokenNumber,
		Token1AmountUint64: args.SolAmount,
	}, nil
}