package types

import (
	"bytes"
	"crypto/ecdsa"
	"math/big"
	"testing"

	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/crypto"
	"github.com/ethereum/go-ethereum/rlp"
)

// The values in those tests are from the Transaction Tests
// at github.com/ethereum/tests.

var (
	emptyTx = NewTransactionMessage(
		common.HexToAddress("095e7baea6a6c7c4c2dfeb977efac326af552d87"),
		big.NewInt(0), big.NewInt(0), big.NewInt(0),
		nil,
	)

	rightvrsRecipient = common.HexToAddress("b94f5374fce5edbc8e2a8697c15331677e6ebf0b")
	rightvrsTx        = &Transaction{
		Recipient:    &rightvrsRecipient,
		AccountNonce: 3,
		Price:        big.NewInt(1),
		GasLimit:     big.NewInt(2000),
		Amount:       big.NewInt(10),
		Payload:      common.FromHex("5544"),
		V:            28,
		R:            common.String2Big("0x98ff921201554726367d2be8c804a7ff89ccf285ebc57dff8ae4c44b9c19ac4a"),
		S:            common.String2Big("0x8887321be575c8095f789dd4c743dfe42c1820f9231f98a962b210e3ac2452a3"),
	}
)

func TestTransactionHash(t *testing.T) {
	// "EmptyTransaction"
	if emptyTx.Hash() != common.HexToHash("c775b99e7ad12f50d819fcd602390467e28141316969f4b57f0626f74fe3b386") {
		t.Errorf("empty transaction hash mismatch, got %x", emptyTx.Hash())
	}

	// "RightVRSTest"
	if rightvrsTx.Hash() != common.HexToHash("fe7a79529ed5f7c3375d06b26b186a8644e0e16c373d7a12be41c62d6042b77a") {
		t.Errorf("RightVRS transaction hash mismatch, got %x", rightvrsTx.Hash())
	}
}

func TestTransactionEncode(t *testing.T) {
	// "RightVRSTest"
	txb, err := rlp.EncodeToBytes(rightvrsTx)
	if err != nil {
		t.Fatalf("encode error: %v", err)
	}
	should := common.FromHex("f86103018207d094b94f5374fce5edbc8e2a8697c15331677e6ebf0b0a8255441ca098ff921201554726367d2be8c804a7ff89ccf285ebc57dff8ae4c44b9c19ac4aa08887321be575c8095f789dd4c743dfe42c1820f9231f98a962b210e3ac2452a3")
	if !bytes.Equal(txb, should) {
		t.Errorf("encoded RLP mismatch, got %x", txb)
	}
}

func decodeTx(data []byte) (*Transaction, error) {
	var tx Transaction
	return &tx, rlp.Decode(bytes.NewReader(data), &tx)
}

func defaultTestKey() (*ecdsa.PrivateKey, []byte) {
	key := crypto.ToECDSA(common.Hex2Bytes("45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8"))
	addr := crypto.PubkeyToAddress(key.PublicKey)
	return key, addr
}

func TestRecipientEmpty(t *testing.T) {
	_, addr := defaultTestKey()

	tx, err := decodeTx(common.Hex2Bytes("f8498080808080011ca09b16de9d5bdee2cf56c28d16275a4da68cd30273e2525f3959f5d62557489921a0372ebd8fb3345f7db7b5a86d42e24d36e983e259b0664ceb8c227ec9af572f3d"))
	if err != nil {
		t.Error(err)
		t.FailNow()
	}

	from, err := tx.From()
	if err != nil {
		t.Error(err)
		t.FailNow()
	}

	if !bytes.Equal(addr, from.Bytes()) {
		t.Error("derived address doesn't match")
	}
}

func TestRecipientNormal(t *testing.T) {
	_, addr := defaultTestKey()

	tx, err := decodeTx(common.Hex2Bytes("f85d80808094000000000000000000000000000000000000000080011ca0527c0d8f5c63f7b9f41324a7c8a563ee1190bcbf0dac8ab446291bdbf32f5c79a0552c4ef0a09a04395074dab9ed34d3fbfb843c2f2546cc30fe89ec143ca94ca6"))
	if err != nil {
		t.Error(err)
		t.FailNow()
	}

	from, err := tx.From()
	if err != nil {
		t.Error(err)
		t.FailNow()
	}

	if !bytes.Equal(addr, from.Bytes()) {
		t.Error("derived address doesn't match")
	}
}