// Copyright 2020 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package core

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

	"github.com/autonity/autonity/core/state"
	"github.com/autonity/autonity/log"

	"golang.org/x/crypto/sha3"

	"github.com/autonity/autonity/common"
	"github.com/autonity/autonity/common/math"
	"github.com/autonity/autonity/consensus"
	"github.com/autonity/autonity/consensus/ethash"
	"github.com/autonity/autonity/consensus/misc"
	"github.com/autonity/autonity/core/rawdb"
	"github.com/autonity/autonity/core/types"
	"github.com/autonity/autonity/core/vm"
	"github.com/autonity/autonity/crypto"
	"github.com/autonity/autonity/params"
	"github.com/autonity/autonity/trie"
)

// TestStateProcessorErrors tests the output from the 'core' errors
// as defined in core/error.go. These errors are generated when the
// blockchain imports bad blocks, meaning blocks which have valid headers but
// contain invalid transactions
func TestStateProcessorErrors(t *testing.T) {
	var (
		config = &params.ChainConfig{
			ChainID:                      big.NewInt(1),
			HomesteadBlock:               big.NewInt(0),
			EIP150Block:                  big.NewInt(0),
			EIP155Block:                  big.NewInt(0),
			EIP158Block:                  big.NewInt(0),
			ByzantiumBlock:               big.NewInt(0),
			ConstantinopleBlock:          big.NewInt(0),
			PetersburgBlock:              big.NewInt(0),
			IstanbulBlock:                big.NewInt(0),
			MuirGlacierBlock:             big.NewInt(0),
			BerlinBlock:                  big.NewInt(0),
			LondonBlock:                  big.NewInt(0),
			Ethash:                       new(params.EthashConfig),
			AutonityContractConfig:       params.TestAutonityContractConfig,
			AccountabilityConfig:         params.DefaultAccountabilityConfig,
			OracleContractConfig:         params.TestOracleConfig,
			OmissionAccountabilityConfig: params.DefaultOmissionAccountabilityConfig,
		}
		signer  = types.LatestSigner(config)
		key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
		key2, _ = crypto.HexToECDSA("0202020202020202020202020202020202020202020202020202002020202020")
	)
	var makeTx = func(key *ecdsa.PrivateKey, nonce uint64, to common.Address, amount *big.Int, gasLimit uint64, gasPrice *big.Int, data []byte) *types.Transaction {
		tx, _ := types.SignTx(types.NewTransaction(nonce, to, amount, gasLimit, gasPrice, data), signer, key)
		return tx
	}
	var mkDynamicTx = func(nonce uint64, to common.Address, gasLimit uint64, gasTipCap, gasFeeCap *big.Int) *types.Transaction {
		tx, _ := types.SignTx(types.NewTx(&types.DynamicFeeTx{
			Nonce:     nonce,
			GasTipCap: gasTipCap,
			GasFeeCap: gasFeeCap,
			Gas:       gasLimit,
			To:        &to,
			Value:     big.NewInt(0),
		}), signer, key1)
		return tx
	}
	{ // Tests against a 'recent' chain definition
		var (
			db    = rawdb.NewMemoryDatabase()
			gspec = &Genesis{
				Config: config,
				Alloc: GenesisAlloc{
					common.HexToAddress("0x71562b71999873DB5b286dF957af199Ec94617F7"): GenesisAccount{
						Balance: big.NewInt(1000000000000000000), // 1 ether
						Nonce:   0,
					},
					common.HexToAddress("0xfd0810DD14796680f72adf1a371963d0745BCc64"): GenesisAccount{
						Balance: big.NewInt(1000000000000000000), // 1 ether
						Nonce:   math.MaxUint64,
					},
				},
			}
			genesis       = gspec.MustCommit(db)
			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, NewTxSenderCacher(), nil, FakeContractBackendProvider(t), log.Root())
		)
		defer blockchain.Stop()
		bigNumber := new(big.Int).SetBytes(common.FromHex("0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"))
		tooBigNumber := new(big.Int).Set(bigNumber)
		tooBigNumber.Add(tooBigNumber, common.Big1)
		for i, tt := range []struct {
			txs  []*types.Transaction
			want string
		}{
			{ // ErrNonceTooLow
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(0), params.TxGas, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
					makeTx(key1, 0, common.Address{}, big.NewInt(0), params.TxGas, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 1 [0x139814609512652602d58019b0fd7cec56cabc054381b464ceea392de04fff66]: nonce too low: address 0x71562b71999873DB5b286dF957af199Ec94617F7, tx: 0 state: 1",
			},
			{ // ErrNonceTooHigh
				txs: []*types.Transaction{
					makeTx(key1, 100, common.Address{}, big.NewInt(0), params.TxGas, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0xd5a6292a8764a54fc5d5095e019490a7a98e780ccf3d7ab9f91027327aba1113]: nonce too high: address 0x71562b71999873DB5b286dF957af199Ec94617F7, tx: 100 state: 0",
			},
			{ // ErrNonceMax
				txs: []*types.Transaction{
					makeTx(key2, math.MaxUint64, common.Address{}, big.NewInt(0), params.TxGas, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0xc56df536af8fcb04eca110333862a1bf50ecad665334c8d8acf361d02085437b]: nonce has max value: address 0xfd0810DD14796680f72adf1a371963d0745BCc64, nonce: 18446744073709551615",
			},
			{ // ErrGasLimitReached
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(0), 21000000, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0xf5eb945992a696cd2af8b855cdf21799194288d28719443759adb38b05f43a80]: gas limit reached",
			},
			{ // ErrInsufficientFundsForTransfer
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(1000000000000000000), params.TxGas, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0xaf22e1319e448e77206a0b711a346381c43bad58d96187adb5189ddedbaf93d3]: insufficient funds for gas * price + value: address 0x71562b71999873DB5b286dF957af199Ec94617F7 have 1000000000000000000 want 1000021000000000000",
			},
			{ // ErrInsufficientFunds
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(0), params.TxGas, big.NewInt(900000000000000000), nil),
				},
				want: "could not apply tx 0 [0x4a69690c4b0cd85e64d0d9ea06302455b01e10a83db964d60281739752003440]: insufficient funds for gas * price + value: address 0x71562b71999873DB5b286dF957af199Ec94617F7 have 1000000000000000000 want 18900000000000000000000",
			},
			// ErrGasUintOverflow
			// One missing 'core' error is ErrGasUintOverflow: "gas uint64 overflow",
			// In order to trigger that one, we'd have to allocate a _huge_ chunk of data, such that the
			// multiplication len(data) +gas_per_byte overflows uint64. Not testable at the moment
			{ // ErrIntrinsicGas
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(0), params.TxGas-1000, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0x2efd3c0832587ab1657277efebe58f505bf1add79cb3ebb5ef354c80f7713676]: intrinsic gas too low: have 20000, want 21000",
			},
			{ // ErrGasLimitReached
				txs: []*types.Transaction{
					makeTx(key1, 0, common.Address{}, big.NewInt(0), params.TxGas*1000, new(big.Int).SetUint64(params.TestMinBaseFee), nil),
				},
				want: "could not apply tx 0 [0xf5eb945992a696cd2af8b855cdf21799194288d28719443759adb38b05f43a80]: gas limit reached",
			},
			{ // ErrFeeCapTooLow
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, big.NewInt(0), big.NewInt(0)),
				},
				want: "could not apply tx 0 [0xc4ab868fef0c82ae0387b742aee87907f2d0fc528fc6ea0a021459fb0fc4a4a8]: max fee per gas less than block base fee: address 0x71562b71999873DB5b286dF957af199Ec94617F7, maxFeePerGas: 0 baseFee: 1000000000",
			},
			{ // ErrTipVeryHigh
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, tooBigNumber, big.NewInt(1)),
				},
				want: "could not apply tx 0 [0x15b8391b9981f266b32f3ab7da564bbeb3d6c21628364ea9b32a21139f89f712]: max priority fee per gas higher than 2^256-1: address 0x71562b71999873DB5b286dF957af199Ec94617F7, maxPriorityFeePerGas bit length: 257",
			},
			{ // ErrFeeCapVeryHigh
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, big.NewInt(1), tooBigNumber),
				},
				want: "could not apply tx 0 [0x48bc299b83fdb345c57478f239e89814bb3063eb4e4b49f3b6057a69255c16bd]: max fee per gas higher than 2^256-1: address 0x71562b71999873DB5b286dF957af199Ec94617F7, maxFeePerGas bit length: 257",
			},
			{ // ErrTipAboveFeeCap
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, big.NewInt(2), big.NewInt(1)),
				},
				want: "could not apply tx 0 [0xf987a31ff0c71895780a7612f965a0c8b056deb54e020bb44fa478092f14c9b4]: max priority fee per gas higher than max fee per gas: address 0x71562b71999873DB5b286dF957af199Ec94617F7, maxPriorityFeePerGas: 2, maxFeePerGas: 1",
			},
			{ // ErrInsufficientFunds
				// Available balance:           1000000000000000000
				// Effective cost:                   18375000021000
				// FeeCap * gas:                1050000000000000000
				// This test is designed to have the effective cost be covered by the balance, but
				// the extended requirement on FeeCap*gas < balance to fail
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, big.NewInt(1), big.NewInt(50000000000000)),
				},
				want: "could not apply tx 0 [0x413603cd096a87f41b1660d3ed3e27d62e1da78eac138961c0a1314ed43bd129]: insufficient funds for gas * price + value: address 0x71562b71999873DB5b286dF957af199Ec94617F7 have 1000000000000000000 want 1050000000000000000",
			},
			{ // Another ErrInsufficientFunds, this one to ensure that feecap/tip of max u256 is allowed
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas, bigNumber, bigNumber),
				},
				want: "could not apply tx 0 [0xd82a0c2519acfeac9a948258c47e784acd20651d9d80f9a1c67b4137651c3a24]: insufficient funds for gas * price + value: address 0x71562b71999873DB5b286dF957af199Ec94617F7 have 1000000000000000000 want 2431633873983640103894990685182446064918669677978451844828609264166175722438635000",
			},
		} {
			block := GenerateBadBlock(genesis, ethash.NewFaker(), tt.txs, gspec.Config)
			_, err := blockchain.InsertChain(types.Blocks{block})
			if err == nil {
				t.Fatal("block imported without errors")
			}
			if have, want := err.Error(), tt.want; have != want {
				t.Errorf("test %d:\nhave \"%v\"\nwant \"%v\"\n", i, have, want)
			}
		}
	}

	// ErrTxTypeNotSupported, For this, we need an older chain
	{
		var (
			db    = rawdb.NewMemoryDatabase()
			gspec = &Genesis{
				Config: &params.ChainConfig{
					ChainID:                      big.NewInt(1),
					HomesteadBlock:               big.NewInt(0),
					EIP150Block:                  big.NewInt(0),
					EIP155Block:                  big.NewInt(0),
					EIP158Block:                  big.NewInt(0),
					ByzantiumBlock:               big.NewInt(0),
					ConstantinopleBlock:          big.NewInt(0),
					PetersburgBlock:              big.NewInt(0),
					IstanbulBlock:                big.NewInt(0),
					MuirGlacierBlock:             big.NewInt(0),
					BerlinBlock:                  big.NewInt(1000),
					LondonBlock:                  big.NewInt(1000),
					AutonityContractConfig:       params.TestAutonityContractConfig,
					AccountabilityConfig:         params.DefaultAccountabilityConfig,
					OracleContractConfig:         params.TestOracleConfig,
					OmissionAccountabilityConfig: params.DefaultOmissionAccountabilityConfig,
				},
				Alloc: GenesisAlloc{
					common.HexToAddress("0x71562b71999873DB5b286dF957af199Ec94617F7"): GenesisAccount{
						Balance: big.NewInt(1000000000000000000), // 1 ether
						Nonce:   0,
					},
				},
			}
			genesis       = gspec.MustCommit(db)
			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, NewTxSenderCacher(), nil, FakeContractBackendProvider(t), log.Root())
		)
		defer blockchain.Stop()
		for i, tt := range []struct {
			txs  []*types.Transaction
			want string
		}{
			{ // ErrTxTypeNotSupported
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas-1000, big.NewInt(0), big.NewInt(0)),
				},
				want: "could not apply tx 0 [0x88626ac0d53cb65308f2416103c62bb1f18b805573d4f96a3640bbbfff13c14f]: transaction type not supported",
			},
		} {
			block := GenerateBadBlock(genesis, ethash.NewFaker(), tt.txs, gspec.Config)
			_, err := blockchain.InsertChain(types.Blocks{block})
			if err == nil {
				t.Fatal("block imported without errors")
			}
			if have, want := err.Error(), tt.want; have != want {
				t.Errorf("test %d:\nhave \"%v\"\nwant \"%v\"\n", i, have, want)
			}
		}
	}

	// ErrSenderNoEOA, for this we need the sender to have contract code
	{
		var (
			db    = rawdb.NewMemoryDatabase()
			gspec = &Genesis{
				Config: config,
				Alloc: GenesisAlloc{
					common.HexToAddress("0x71562b71999873DB5b286dF957af199Ec94617F7"): GenesisAccount{
						Balance: big.NewInt(1000000000000000000), // 1 ether
						Nonce:   0,
						Code:    common.FromHex("0xB0B0FACE"),
					},
				},
			}
			genesis       = gspec.MustCommit(db)
			blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, NewTxSenderCacher(), nil, FakeContractBackendProvider(t), log.Root())
		)
		defer blockchain.Stop()
		for i, tt := range []struct {
			txs  []*types.Transaction
			want string
		}{
			{ // ErrSenderNoEOA
				txs: []*types.Transaction{
					mkDynamicTx(0, common.Address{}, params.TxGas-1000, big.NewInt(0), big.NewInt(0)),
				},
				want: "could not apply tx 0 [0x88626ac0d53cb65308f2416103c62bb1f18b805573d4f96a3640bbbfff13c14f]: sender not an eoa: address 0x71562b71999873DB5b286dF957af199Ec94617F7, codehash: 0x9280914443471259d4570a8661015ae4a5b80186dbc619658fb494bebc3da3d1",
			},
		} {
			block := GenerateBadBlock(genesis, ethash.NewFaker(), tt.txs, gspec.Config)
			_, err := blockchain.InsertChain(types.Blocks{block})
			if err == nil {
				t.Fatal("block imported without errors")
			}
			if have, want := err.Error(), tt.want; have != want {
				t.Errorf("test %d:\nhave \"%v\"\nwant \"%v\"\n", i, have, want)
			}
		}
	}
}

// GenerateBadBlock constructs a "block" which contains the transactions. The transactions are not expected to be
// valid, and no proper post-state can be made. But from the perspective of the blockchain, the block is sufficiently
// valid to be considered for import:
// - valid pow (fake), ancestry, difficulty, gaslimit etc
func GenerateBadBlock(parent *types.Block, engine consensus.Engine, txs types.Transactions, config *params.ChainConfig) *types.Block {

	chainReader := &fakeChainReader{config, nil}
	header := &types.Header{
		ParentHash: parent.Hash(),
		Coinbase:   parent.Coinbase(),
		Difficulty: engine.CalcDifficulty(chainReader, parent.Time()+10, &types.Header{
			Number:     parent.Number(),
			Time:       parent.Time(),
			Difficulty: parent.Difficulty(),
			UncleHash:  parent.UncleHash(),
		}),
		GasLimit:  parent.GasLimit(),
		Number:    new(big.Int).Add(parent.Number(), common.Big1),
		Time:      parent.Time() + 10,
		UncleHash: types.EmptyUncleHash,
	}
	if config.IsLondon(header.Number) {
		eip1559Params, err := chainReader.Eip1559ParamsByHeight(parent.NumberU64() + 1)
		if err != nil {
			panic("cannot fetch eip1559 params: " + err.Error())
		}
		header.BaseFee = misc.CalcBaseFee(config, parent.Header(), eip1559Params)
	}
	var receipts []*types.Receipt
	// The post-state result doesn't need to be correct (this is a bad block), but we do need something there
	// Preferably something unique. So let's use a combo of blocknum + txhash
	hasher := sha3.NewLegacyKeccak256()
	hasher.Write(header.Number.Bytes())
	var cumulativeGas uint64
	for _, tx := range txs {
		txh := tx.Hash()
		hasher.Write(txh[:])
		receipt := types.NewReceipt(nil, false, cumulativeGas+tx.Gas())
		receipt.TxHash = tx.Hash()
		receipt.GasUsed = tx.Gas()
		receipts = append(receipts, receipt)
		cumulativeGas += tx.Gas()
	}
	header.Root = common.BytesToHash(hasher.Sum(nil))
	// Assemble and return the final block for sealing
	return types.NewBlock(header, txs, nil, receipts, trie.NewStackTrie(nil))
}

func BenchmarkStateProcessor(b *testing.B) {
	// Step 1 : generate txs
	const txCount = 1000
	var (
		config  = params.TestChainConfig
		signer  = types.LatestSigner(config)
		key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
		//key2, _ = crypto.HexToECDSA("0202020202020202020202020202020202020202020202020202002020202020")
		db    = rawdb.NewMemoryDatabase()
		gspec = &Genesis{
			Config:   config,
			GasLimit: 1_000_000_000,
			Alloc: GenesisAlloc{
				common.HexToAddress("0x71562b71999873DB5b286dF957af199Ec94617F7"): GenesisAccount{
					Balance: big.NewInt(1000000000000000000), // 1 ether
					Nonce:   0,
				},
				common.HexToAddress("0xfd0810DD14796680f72adf1a371963d0745BCc64"): GenesisAccount{
					Balance: big.NewInt(1000000000000000000), // 1 ether
					Nonce:   math.MaxUint64,
				},
			},
		}
		genesis       = gspec.MustCommit(db)
		blockchain, _ = NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{}, nil, NewTxSenderCacher(), nil, FakeContractBackendProvider(b), log.Root())
	)
	mkDynamicTx := func(nonce uint64, to common.Address, gasLimit uint64, gasTipCap, gasFeeCap *big.Int) *types.Transaction {
		tx, _ := types.SignTx(types.NewTx(&types.DynamicFeeTx{
			Nonce:     nonce,
			GasTipCap: gasTipCap,
			GasFeeCap: gasFeeCap,
			Gas:       gasLimit,
			To:        &to,
			Value:     big.NewInt(1),
		}), signer, key1)
		return tx
	}
	var txs []*types.Transaction
	for i := 0; i < txCount; i++ {
		txs = append(txs, mkDynamicTx(uint64(i), common.Address{}, params.TxGas, big.NewInt(0), genesis.BaseFee()))
	}
	// We need to import a state here
	block := GenerateBadBlock(genesis, ethash.NewFaker(), txs, gspec.Config)
	header := block.Header()
	// Setup phase complere
	b.ResetTimer()
	// Step 2: process block

	// Create a new context to be used in the EVM environment
	for j := 0; j < b.N; j++ {
		blockContext := NewEVMBlockContext(block.Header(), blockchain, &header.Coinbase)
		usedGas := new(uint64)
		statedb, _ := state.New(genesis.Root(), blockchain.stateCache, blockchain.snaps)
		vmenv := vm.NewEVM(blockContext, vm.TxContext{}, statedb, config, vm.Config{})
		gp := new(GasPool).AddGas(block.GasLimit())
		for i, tx := range txs {
			msg, _ := tx.AsMessage(types.MakeSigner(config, header.Number), header.BaseFee)
			statedb.Prepare(tx.Hash(), i)
			if _, err := applyTransaction(msg, config, blockchain, nil, gp, statedb, header.Number, header.Hash(), tx, usedGas, vmenv); err != nil {
				b.Fatal(err)
			}
		}
		_ = statedb.IntermediateRoot(true)
	}
}
