package depositcontract_test

import (
	"context"
	"encoding/binary"
	"math/big"
	"testing"

	"github.com/ethereum/go-ethereum"
	"github.com/ethereum/go-ethereum/common"
	depositcontract "github.com/prysmaticlabs/prysm/contracts/deposit-contract"
	"github.com/prysmaticlabs/prysm/shared/interop"
	"github.com/prysmaticlabs/prysm/shared/testutil/assert"
	"github.com/prysmaticlabs/prysm/shared/testutil/require"
)

func TestSetupRegistrationContract_OK(t *testing.T) {
	_, err := depositcontract.Setup()
	assert.NoError(t, err, "Can not deploy validator registration contract")
}

// negative test case, deposit with less than 1 ETH which is less than the top off amount.
func TestRegister_Below1ETH(t *testing.T) {
	testAccount, err := depositcontract.Setup()
	require.NoError(t, err)

	// Generate deposit data
	privKeys, pubKeys, err := interop.DeterministicallyGenerateKeys(0 /*startIndex*/, 1)
	require.NoError(t, err)
	depositDataItems, depositDataRoots, err := interop.DepositDataFromKeys(privKeys, pubKeys)
	require.NoError(t, err)

	var depositDataRoot [32]byte
	copy(depositDataRoot[:], depositDataRoots[0])
	testAccount.TxOpts.Value = depositcontract.LessThan1Eth()
	_, err = testAccount.Contract.Deposit(testAccount.TxOpts, pubKeys[0].Marshal(), depositDataItems[0].WithdrawalCredentials, depositDataItems[0].Signature, depositDataRoot)
	assert.ErrorContains(t, "execution reverted", err, "Validator registration should have failed with insufficient deposit")
}

// normal test case, test depositing 32 ETH and verify HashChainValue event is correctly emitted.
func TestValidatorRegister_OK(t *testing.T) {
	testAccount, err := depositcontract.Setup()
	require.NoError(t, err)
	testAccount.TxOpts.Value = depositcontract.Amount32Eth()

	// Generate deposit data
	privKeys, pubKeys, err := interop.DeterministicallyGenerateKeys(0 /*startIndex*/, 1)
	require.NoError(t, err)
	depositDataItems, depositDataRoots, err := interop.DepositDataFromKeys(privKeys, pubKeys)
	require.NoError(t, err)

	var depositDataRoot [32]byte
	copy(depositDataRoot[:], depositDataRoots[0])
	_, err = testAccount.Contract.Deposit(testAccount.TxOpts, pubKeys[0].Marshal(), depositDataItems[0].WithdrawalCredentials, depositDataItems[0].Signature, depositDataRoot)
	testAccount.Backend.Commit()
	require.NoError(t, err, "Validator registration failed")
	_, err = testAccount.Contract.Deposit(testAccount.TxOpts, pubKeys[0].Marshal(), depositDataItems[0].WithdrawalCredentials, depositDataItems[0].Signature, depositDataRoot)
	testAccount.Backend.Commit()
	assert.NoError(t, err, "Validator registration failed")
	_, err = testAccount.Contract.Deposit(testAccount.TxOpts, pubKeys[0].Marshal(), depositDataItems[0].WithdrawalCredentials, depositDataItems[0].Signature, depositDataRoot)
	testAccount.Backend.Commit()
	assert.NoError(t, err, "Validator registration failed")

	query := ethereum.FilterQuery{
		Addresses: []common.Address{
			testAccount.ContractAddr,
		},
	}

	logs, err := testAccount.Backend.FilterLogs(context.Background(), query)
	assert.NoError(t, err, "Unable to get logs of deposit contract")

	merkleTreeIndex := make([]uint64, 5)

	for i, log := range logs {
		_, _, _, _, idx, err := depositcontract.UnpackDepositLogData(log.Data)
		require.NoError(t, err, "Unable to unpack log data")
		merkleTreeIndex[i] = binary.LittleEndian.Uint64(idx)
	}

	assert.Equal(t, uint64(0), merkleTreeIndex[0], "Deposit event total desposit count miss matched")
	assert.Equal(t, uint64(1), merkleTreeIndex[1], "Deposit event total desposit count miss matched")
	assert.Equal(t, uint64(2), merkleTreeIndex[2], "Deposit event total desposit count miss matched")
}

func TestDrain(t *testing.T) {
	testAccount, err := depositcontract.Setup()
	require.NoError(t, err)
	testAccount.TxOpts.Value = depositcontract.Amount32Eth()

	// Generate deposit data
	privKeys, pubKeys, err := interop.DeterministicallyGenerateKeys(0 /*startIndex*/, 1)
	require.NoError(t, err)
	depositDataItems, depositDataRoots, err := interop.DepositDataFromKeys(privKeys, pubKeys)
	require.NoError(t, err)

	var depositDataRoot [32]byte
	copy(depositDataRoot[:], depositDataRoots[0])
	_, err = testAccount.Contract.Deposit(testAccount.TxOpts, pubKeys[0].Marshal(), depositDataItems[0].WithdrawalCredentials, depositDataItems[0].Signature, depositDataRoot)
	testAccount.Backend.Commit()
	require.NoError(t, err, "Validator registration failed")

	testAccount.Backend.Commit()

	ctx := context.Background()
	bal, err := testAccount.Backend.BalanceAt(ctx, testAccount.ContractAddr, nil)
	require.NoError(t, err)
	require.Equal(t, 0, bal.Cmp(depositcontract.Amount32Eth()), "Deposit did not work")

	testAccount.TxOpts.Value = big.NewInt(0)
	_, err = testAccount.Contract.Drain(testAccount.TxOpts)
	require.NoError(t, err)

	testAccount.Backend.Commit()

	bal, err = testAccount.Backend.BalanceAt(ctx, testAccount.ContractAddr, nil)
	require.NoError(t, err)
	assert.Equal(t, 0, big.NewInt(0).Cmp(bal), "Drain did not drain balance")
}