// 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 core

import (
	"fmt"
	"math/big"
	"testing"

	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/core/state"
	"github.com/ethereum/go-ethereum/core/types"
	"github.com/ethereum/go-ethereum/core/vm"
	"github.com/ethereum/go-ethereum/ethdb"
	"github.com/ethereum/go-ethereum/event"
	"github.com/ethereum/go-ethereum/params"
	"github.com/ethereum/go-ethereum/pow/ezp"
)

func testChainConfig() *ChainConfig {
	return &ChainConfig{HomesteadBlock: big.NewInt(0)}
}

func proc() (Validator, *BlockChain) {
	db, _ := ethdb.NewMemDatabase()
	var mux event.TypeMux

	WriteTestNetGenesisBlock(db)
	blockchain, err := NewBlockChain(db, testChainConfig(), thePow(), &mux)
	if err != nil {
		fmt.Println(err)
	}
	return blockchain.validator, blockchain
}

func TestNumber(t *testing.T) {
	pow := ezp.New()
	_, chain := proc()

	statedb, _ := state.New(chain.Genesis().Root(), chain.chainDb)
	header := makeHeader(chain.Genesis(), statedb)
	header.Number = big.NewInt(3)
	cfg := testChainConfig()
	err := ValidateHeader(cfg, pow, header, chain.Genesis().Header(), false, false)
	if err != BlockNumberErr {
		t.Errorf("expected block number error, got %q", err)
	}

	header = makeHeader(chain.Genesis(), statedb)
	err = ValidateHeader(cfg, pow, header, chain.Genesis().Header(), false, false)
	if err == BlockNumberErr {
		t.Errorf("didn't expect block number error")
	}
}

func TestPutReceipt(t *testing.T) {
	db, _ := ethdb.NewMemDatabase()

	var addr common.Address
	addr[0] = 1
	var hash common.Hash
	hash[0] = 2

	receipt := new(types.Receipt)
	receipt.Logs = vm.Logs{&vm.Log{
		Address:     addr,
		Topics:      []common.Hash{hash},
		Data:        []byte("hi"),
		BlockNumber: 42,
		TxHash:      hash,
		TxIndex:     0,
		BlockHash:   hash,
		Index:       0,
	}}

	WriteReceipts(db, types.Receipts{receipt})
	receipt = GetReceipt(db, common.Hash{})
	if receipt == nil {
		t.Error("expected to get 1 receipt, got none.")
	}
}

// Tests that DAO-fork enabled clients can properly filter out fork-commencing
// blocks based on their extradata fields.
func TestDAOForkRangeExtradata(t *testing.T) {
	forkBlock := big.NewInt(32)

	// Generate a common prefix for both pro-forkers and non-forkers
	db, _ := ethdb.NewMemDatabase()
	genesis := WriteGenesisBlockForTesting(db)
	prefix, _ := GenerateChain(genesis, db, int(forkBlock.Int64()-1), func(i int, gen *BlockGen) {})

	// Create the concurrent, conflicting two nodes
	proDb, _ := ethdb.NewMemDatabase()
	WriteGenesisBlockForTesting(proDb)
	proBc, _ := NewBlockChain(proDb, &ChainConfig{HomesteadBlock: big.NewInt(0), DAOForkBlock: forkBlock, DAOForkSupport: true}, new(FakePow), new(event.TypeMux))

	conDb, _ := ethdb.NewMemDatabase()
	WriteGenesisBlockForTesting(conDb)
	conBc, _ := NewBlockChain(conDb, &ChainConfig{HomesteadBlock: big.NewInt(0), DAOForkBlock: forkBlock, DAOForkSupport: false}, new(FakePow), new(event.TypeMux))

	if _, err := proBc.InsertChain(prefix); err != nil {
		t.Fatalf("pro-fork: failed to import chain prefix: %v", err)
	}
	if _, err := conBc.InsertChain(prefix); err != nil {
		t.Fatalf("con-fork: failed to import chain prefix: %v", err)
	}
	// Try to expand both pro-fork and non-fork chains iteratively with other camp's blocks
	for i := int64(0); i < params.DAOForkExtraRange.Int64(); i++ {
		// Create a pro-fork block, and try to feed into the no-fork chain
		db, _ = ethdb.NewMemDatabase()
		WriteGenesisBlockForTesting(db)
		bc, _ := NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))

		blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()+1))
		for j := 0; j < len(blocks)/2; j++ {
			blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
		}
		if _, err := bc.InsertChain(blocks); err != nil {
			t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
		}
		blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
		if _, err := conBc.InsertChain(blocks); err == nil {
			t.Fatalf("contra-fork chain accepted pro-fork block: %v", blocks[0])
		}
		// Create a proper no-fork block for the contra-forker
		blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
		if _, err := conBc.InsertChain(blocks); err != nil {
			t.Fatalf("contra-fork chain didn't accepted no-fork block: %v", err)
		}
		// Create a no-fork block, and try to feed into the pro-fork chain
		db, _ = ethdb.NewMemDatabase()
		WriteGenesisBlockForTesting(db)
		bc, _ = NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))

		blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()+1))
		for j := 0; j < len(blocks)/2; j++ {
			blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
		}
		if _, err := bc.InsertChain(blocks); err != nil {
			t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
		}
		blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
		if _, err := proBc.InsertChain(blocks); err == nil {
			t.Fatalf("pro-fork chain accepted contra-fork block: %v", blocks[0])
		}
		// Create a proper pro-fork block for the pro-forker
		blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
		if _, err := proBc.InsertChain(blocks); err != nil {
			t.Fatalf("pro-fork chain didn't accepted pro-fork block: %v", err)
		}
	}
	// Verify that contra-forkers accept pro-fork extra-datas after forking finishes
	db, _ = ethdb.NewMemDatabase()
	WriteGenesisBlockForTesting(db)
	bc, _ := NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))

	blocks := conBc.GetBlocksFromHash(conBc.CurrentBlock().Hash(), int(conBc.CurrentBlock().NumberU64()+1))
	for j := 0; j < len(blocks)/2; j++ {
		blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
	}
	if _, err := bc.InsertChain(blocks); err != nil {
		t.Fatalf("failed to import contra-fork chain for expansion: %v", err)
	}
	blocks, _ = GenerateChain(conBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) { gen.SetExtra(params.DAOForkBlockExtra) })
	if _, err := conBc.InsertChain(blocks); err != nil {
		t.Fatalf("contra-fork chain didn't accept pro-fork block post-fork: %v", err)
	}
	// Verify that pro-forkers accept contra-fork extra-datas after forking finishes
	db, _ = ethdb.NewMemDatabase()
	WriteGenesisBlockForTesting(db)
	bc, _ = NewBlockChain(db, &ChainConfig{HomesteadBlock: big.NewInt(0)}, new(FakePow), new(event.TypeMux))

	blocks = proBc.GetBlocksFromHash(proBc.CurrentBlock().Hash(), int(proBc.CurrentBlock().NumberU64()+1))
	for j := 0; j < len(blocks)/2; j++ {
		blocks[j], blocks[len(blocks)-1-j] = blocks[len(blocks)-1-j], blocks[j]
	}
	if _, err := bc.InsertChain(blocks); err != nil {
		t.Fatalf("failed to import pro-fork chain for expansion: %v", err)
	}
	blocks, _ = GenerateChain(proBc.CurrentBlock(), db, 1, func(i int, gen *BlockGen) {})
	if _, err := proBc.InsertChain(blocks); err != nil {
		t.Fatalf("pro-fork chain didn't accept contra-fork block post-fork: %v", err)
	}
}