package pump_parser

import (
	"encoding/binary"

	"github.com/shopspring/decimal"
)

type setComputeData struct {
	Units uint64
}

func budgetParser(tx *Tx, instr Instruction, _ InnerInstructions, offset [2]uint) ([2]uint, error) {
	if offset[1] != 0 {
		return increaseOffset(offset), nil
	}
	decode := instr.Data
	discriminator := decode[0]

	switch discriminator {
	case setComputeUnitLimitDiscriminator:
		return computeUnitLimitParser(offset, tx, decode[1:])
	case setComputeUnitPriceDiscriminator:
		return computeUnitPriceParser(offset, tx, decode[1:])
	default:
		return increaseOffset(offset), nil
	}
}

func computeUnitLimitParser(offset [2]uint, tx *Tx, decodedData []byte) ([2]uint, error) {
	if len(decodedData) < 4 {
		return increaseOffset(offset), nil
	}
	tx.CuLimit = binary.LittleEndian.Uint32(decodedData[:4])
	return increaseOffset(offset), nil
}

func computeUnitPriceParser(offset [2]uint, tx *Tx, decodedData []byte) ([2]uint, error) {
	if len(decodedData) < 8 {
		return increaseOffset(offset), nil
	}

	cuPrice := binary.LittleEndian.Uint64(decodedData[:8])
	tx.CUPrice = decimal.NewFromInt(int64(cuPrice)).Div(decimal.NewFromInt(1000000)) // cu decimals

	return increaseOffset(offset), nil
}