package coreth

import (
	"crypto/ecdsa"
	"fmt"
	"io"
	"os"

	"github.com/ava-labs/coreth/consensus/dummy"
	"github.com/ava-labs/coreth/core"
	"github.com/ava-labs/coreth/core/state"
	"github.com/ava-labs/coreth/core/types"
	"github.com/ava-labs/coreth/eth"
	"github.com/ava-labs/coreth/miner"
	"github.com/ava-labs/coreth/node"
	"github.com/ava-labs/coreth/rpc"
	"github.com/ava-labs/go-ethereum/common"
	"github.com/ava-labs/go-ethereum/crypto"
	"github.com/ava-labs/go-ethereum/ethdb"
	"github.com/ava-labs/go-ethereum/event"
	"github.com/ava-labs/go-ethereum/log"
	"github.com/mattn/go-isatty"
)

var (
	BlackholeAddr = common.Address{
		1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	}
)

type Tx = types.Transaction
type Block = types.Block
type Hash = common.Hash

type ETHChain struct {
	backend *eth.Ethereum
	cb      *dummy.ConsensusCallbacks
	mcb     *miner.MinerCallbacks
	bcb     *eth.BackendCallbacks
}

func isLocalBlock(block *types.Block) bool {
	return false
}

// NewETHChain creates an Ethereum blockchain with the given configs.
func NewETHChain(config *eth.Config, nodecfg *node.Config, etherBase *common.Address, chainDB ethdb.Database) *ETHChain {
	if config == nil {
		config = &eth.DefaultConfig
	}
	if nodecfg == nil {
		nodecfg = &node.Config{}
	}
	mux := new(event.TypeMux)
	ctx, ep, err := node.NewServiceContext(nodecfg, mux)
	if err != nil {
		panic(err)
	}
	if ep != "" {
		log.Info(fmt.Sprintf("temporary keystore = %s", ep))
	}
	cb := new(dummy.ConsensusCallbacks)
	mcb := new(miner.MinerCallbacks)
	bcb := new(eth.BackendCallbacks)
	backend, _ := eth.New(&ctx, config, cb, mcb, bcb, chainDB)
	chain := &ETHChain{backend: backend, cb: cb, mcb: mcb, bcb: bcb}
	if etherBase == nil {
		etherBase = &BlackholeAddr
	}
	backend.SetEtherbase(*etherBase)
	return chain
}

func (self *ETHChain) Start() {
	self.backend.StartMining(0)
}

func (self *ETHChain) Stop() {
	self.backend.StopPart()
}

func (self *ETHChain) GenBlock() {
	self.backend.Miner().GenBlock()
}

func (self *ETHChain) PendingSize() (int, error) {
	pending, err := self.backend.TxPool().Pending()
	count := 0
	for _, txs := range pending {
		count += len(txs)
	}
	return count, err
}

func (self *ETHChain) AddRemoteTxs(txs []*types.Transaction) []error {
	return self.backend.TxPool().AddRemotes(txs)
}

func (self *ETHChain) AddLocalTxs(txs []*types.Transaction) []error {
	return self.backend.TxPool().AddLocals(txs)
}

func (self *ETHChain) SetOnSeal(cb func(*types.Block) error) {
	self.cb.OnSeal = cb
}

func (self *ETHChain) SetOnSealHash(cb func(*types.Header)) {
	self.cb.OnSealHash = cb
}

func (self *ETHChain) SetOnSealFinish(cb func(*types.Block) error) {
	self.mcb.OnSealFinish = cb
}

func (self *ETHChain) SetOnHeaderNew(cb func(*types.Header)) {
	self.mcb.OnHeaderNew = cb
}

func (self *ETHChain) SetOnSealDrop(cb func(*types.Block)) {
	self.mcb.OnSealDrop = cb
}

func (self *ETHChain) SetOnAPIs(cb dummy.OnAPIsCallbackType) {
	self.cb.OnAPIs = cb
}

func (self *ETHChain) SetOnFinalize(cb dummy.OnFinalizeCallbackType) {
	self.cb.OnFinalize = cb
}

func (self *ETHChain) SetOnFinalizeAndAssemble(cb dummy.OnFinalizeAndAssembleCallbackType) {
	self.cb.OnFinalizeAndAssemble = cb
}

func (self *ETHChain) SetOnQueryAcceptedBlock(cb func() *types.Block) {
	self.bcb.OnQueryAcceptedBlock = cb
}

// Returns a new mutable state based on the current HEAD block.
func (self *ETHChain) CurrentState() (*state.StateDB, error) {
	return self.backend.BlockChain().State()
}

// Returns a new mutable state based on the given block.
func (self *ETHChain) BlockState(block *types.Block) (*state.StateDB, error) {
	return self.backend.BlockChain().StateAt(block.Root())
}

// Retrives a block from the database by hash.
func (self *ETHChain) GetBlockByHash(hash common.Hash) *types.Block {
	return self.backend.BlockChain().GetBlockByHash(hash)
}

// SetTail sets the current head block to the one defined by the hash
// irrelevant what the chain contents were prior.
func (self *ETHChain) SetTail(hash common.Hash) error {
	return self.backend.BlockChain().ManualHead(hash)
}

func (self *ETHChain) GetReceiptsByHash(hash common.Hash) types.Receipts {
	return self.backend.BlockChain().GetReceiptsByHash(hash)
}

func (self *ETHChain) GetGenesisBlock() *types.Block {
	return self.backend.BlockChain().Genesis()
}

func (self *ETHChain) InsertChain(chain []*types.Block) (int, error) {
	return self.backend.BlockChain().InsertChain(chain)
}

func (self *ETHChain) NewRPCHandler() *rpc.Server {
	return rpc.NewServer()
}

func (self *ETHChain) AttachEthService(handler *rpc.Server, namespaces []string) {
	nsmap := make(map[string]bool)
	for _, ns := range namespaces {
		nsmap[ns] = true
	}
	for _, api := range self.backend.APIs() {
		if nsmap[api.Namespace] {
			handler.RegisterName(api.Namespace, api.Service)
		}
	}
}

// TODO: use SubscribeNewTxsEvent()
func (self *ETHChain) GetTxSubmitCh() <-chan struct{} {
	return self.backend.GetTxSubmitCh()
}

func (self *ETHChain) GetTxPool() *core.TxPool {
	return self.backend.TxPool()
}

type Key struct {
	Address    common.Address
	PrivateKey *ecdsa.PrivateKey
}

func NewKeyFromECDSA(privateKeyECDSA *ecdsa.PrivateKey) *Key {
	key := &Key{
		Address:    crypto.PubkeyToAddress(privateKeyECDSA.PublicKey),
		PrivateKey: privateKeyECDSA,
	}
	return key
}

func NewKey(rand io.Reader) (*Key, error) {
	privateKeyECDSA, err := ecdsa.GenerateKey(crypto.S256(), rand)
	if err != nil {
		return nil, err
	}
	return NewKeyFromECDSA(privateKeyECDSA), nil
}

func init() {
	usecolor := (isatty.IsTerminal(os.Stderr.Fd()) || isatty.IsCygwinTerminal(os.Stderr.Fd())) && os.Getenv("TERM") != "dumb"
	glogger := log.StreamHandler(io.Writer(os.Stderr), log.TerminalFormat(usecolor))
	log.Root().SetHandler(glogger)
}