Fantom-foundation/go-lachesis

// Copyright 2015 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 evmcore

import (
    "math"
    "math/big"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/trie"

    "github.com/Fantom-foundation/go-lachesis/inter"
)

type (
    EvmHeader struct {
        Number     *big.Int
        Hash       common.Hash
        ParentHash common.Hash
        Root       common.Hash
        TxHash     common.Hash
        Time       inter.Timestamp
        Coinbase   common.Address

        GasLimit uint64
        GasUsed  uint64
    }

    EvmBlock struct {
        EvmHeader

        Transactions types.Transactions
    }
)

// ToEvmHeader converts inter.Block to EvmHeader.
func ToEvmHeader(block *inter.Block) *EvmHeader {
    return &EvmHeader{
        Hash:       common.Hash(block.Atropos),
        ParentHash: common.Hash(block.PrevHash),
        Root:       common.Hash(block.Root),
        TxHash:     block.TxHash,
        Number:     big.NewInt(int64(block.Index)),
        Time:       block.Time,
        GasLimit:   math.MaxUint64,
        GasUsed:    block.GasUsed,
    }
}

// ConvertFromEthHeader converts ETH-formatted header to Lachesis EVM header
func ConvertFromEthHeader(h *types.Header) *EvmHeader {
    // NOTE: incomplete conversion
    return &EvmHeader{
        Number:     h.Number,
        Coinbase:   h.Coinbase,
        GasLimit:   math.MaxUint64,
        GasUsed:    h.GasUsed,
        Root:       h.Root,
        TxHash:     h.TxHash,
        ParentHash: h.ParentHash,
        Time:       inter.FromUnix(int64(h.Time)),
        Hash:       common.BytesToHash(h.Extra),
    }
}

// EthHeader returns header in ETH format
func (h *EvmHeader) EthHeader() *types.Header {
    // NOTE: incomplete conversion
    return &types.Header{
        Number:     h.Number,
        Coinbase:   h.Coinbase,
        GasLimit:   0xffffffffffff, // don't use h.GasLimit (too much bits) here to avoid parsing issues
        GasUsed:    h.GasUsed,
        Root:       h.Root,
        TxHash:     h.TxHash,
        ParentHash: h.ParentHash,
        Time:       uint64(h.Time.Unix()),
        Extra:      h.Hash.Bytes(),

        Difficulty: new(big.Int),
    }
}

// Header is a copy of EvmBlock.EvmHeader.
func (b *EvmBlock) Header() *EvmHeader {
    if b == nil {
        return nil
    }
    // copy values
    h := b.EvmHeader
    // copy refs
    h.Number = new(big.Int).Set(b.Number)

    return &h
}

func (b *EvmBlock) NumberU64() uint64 {
    return b.Number.Uint64()
}

func (b *EvmBlock) EthBlock() *types.Block {
    if b == nil {
        return nil
    }
    return types.NewBlock(b.EvmHeader.EthHeader(), b.Transactions, nil, nil, new(trie.Trie))
}