package commands

import (
	"context"
	"encoding/hex"
	"errors"
	"fmt"
	"github.com/ledgerwatch/erigon-lib/metrics"
	"path/filepath"
	"runtime"
	"strings"
	"time"

	"github.com/holiman/uint256"
	"github.com/ledgerwatch/log/v3"
	"github.com/spf13/cobra"

	"github.com/ledgerwatch/erigon-lib/commitment"
	libcommon "github.com/ledgerwatch/erigon-lib/common"
	"github.com/ledgerwatch/erigon-lib/common/datadir"
	"github.com/ledgerwatch/erigon-lib/common/dbg"
	"github.com/ledgerwatch/erigon-lib/common/length"
	"github.com/ledgerwatch/erigon-lib/kv"
	kv2 "github.com/ledgerwatch/erigon-lib/kv/mdbx"
	libstate "github.com/ledgerwatch/erigon-lib/state"

	"github.com/ledgerwatch/erigon/cmd/utils"
	"github.com/ledgerwatch/erigon/core"
	"github.com/ledgerwatch/erigon/core/types/accounts"
	"github.com/ledgerwatch/erigon/eth/ethconfig"
	"github.com/ledgerwatch/erigon/node/nodecfg"
	erigoncli "github.com/ledgerwatch/erigon/turbo/cli"
	"github.com/ledgerwatch/erigon/turbo/debug"
)

func init() {
	withDataDir(readDomains)
	withChain(readDomains)
	withHeimdall(readDomains)
	withWorkers(readDomains)
	withStartTx(readDomains)

	rootCmd.AddCommand(readDomains)
}

// if trie variant is not hex, we could not have another rootHash with to verify it
var (
	stepSize                  uint64
	lastStep                  uint64
	dirtySpaceThreshold       = uint64(2 * 1024 * 1024 * 1024) /* threshold of dirty space in MDBX transaction that triggers a commit */
	blockRootMismatchExpected bool

	mxBlockExecutionTimer = metrics.GetOrCreateSummary("chain_execution_seconds")
	mxCommitTook          = metrics.GetOrCreateHistogram("domain_commit_took")
)

// write command to just seek and query state by addr and domain from state db and files (if any)
var readDomains = &cobra.Command{
	Use:       "read_domains",
	Short:     `Run block execution and commitment with Domains.`,
	Example:   "go run ./cmd/integration read_domains --datadir=... --verbosity=3",
	ValidArgs: []string{"account", "storage", "code", "commitment"},
	Args:      cobra.ArbitraryArgs,
	Run: func(cmd *cobra.Command, args []string) {
		logger := debug.SetupCobra(cmd, "integration")
		ctx, _ := libcommon.RootContext()
		cfg := &nodecfg.DefaultConfig
		utils.SetNodeConfigCobra(cmd, cfg)
		ethConfig := &ethconfig.Defaults
		ethConfig.Genesis = core.GenesisBlockByChainName(chain)
		erigoncli.ApplyFlagsForEthConfigCobra(cmd.Flags(), ethConfig)

		var readFromDomain string
		var addrs [][]byte
		for i := 0; i < len(args); i++ {
			if i == 0 {
				switch s := strings.ToLower(args[i]); s {
				case "account", "storage", "code", "commitment":
					readFromDomain = s
				default:
					logger.Error("invalid domain to read from", "arg", args[i])
					return
				}
				continue
			}
			addr, err := hex.DecodeString(strings.TrimPrefix(args[i], "0x"))
			if err != nil {
				logger.Warn("invalid address passed", "str", args[i], "at position", i, "err", err)
				continue
			}
			addrs = append(addrs, addr)
		}

		dirs := datadir.New(datadirCli)
		chainDb, err := openDB(dbCfg(kv.ChainDB, dirs.Chaindata), true, logger)
		if err != nil {
			logger.Error("Opening DB", "error", err)
			return
		}
		defer chainDb.Close()

		stateDb, err := kv2.NewMDBX(log.New()).Path(filepath.Join(dirs.DataDir, "statedb")).WriteMap().Open(ctx)
		if err != nil {
			return
		}
		defer stateDb.Close()

		if err := requestDomains(chainDb, stateDb, ctx, readFromDomain, addrs, logger); err != nil {
			if !errors.Is(err, context.Canceled) {
				logger.Error(err.Error())
			}
			return
		}
	},
}

func requestDomains(chainDb, stateDb kv.RwDB, ctx context.Context, readDomain string, addrs [][]byte, logger log.Logger) error {
	trieVariant := commitment.ParseTrieVariant(commitmentTrie)
	if trieVariant != commitment.VariantHexPatriciaTrie {
		blockRootMismatchExpected = true
	}
	mode := libstate.ParseCommitmentMode(commitmentMode)
	libstate.COMPARE_INDEXES = true

	_, _, _, agg := newDomains(ctx, chainDb, stepSize, mode, trieVariant, logger)
	defer agg.Close()

	histTx, err := chainDb.BeginRo(ctx)
	must(err)
	defer histTx.Rollback()

	stateTx, err := stateDb.BeginRw(ctx)
	must(err)
	defer stateTx.Rollback()

	agg.SetTx(stateTx)
	defer agg.StartWrites().FinishWrites()

	latestBlock, latestTx, err := agg.SeekCommitment()
	if err != nil && startTxNum != 0 {
		return fmt.Errorf("failed to seek commitment to tx %d: %w", startTxNum, err)
	}
	if latestTx < startTxNum {
		return fmt.Errorf("latest available tx to start is  %d and its less than start tx %d", latestTx, startTxNum)
	}
	if latestTx > 0 {
		logger.Info("aggregator files opened", "txn", latestTx, "block", latestBlock)
	}
	agg.SetTxNum(latestTx)

	r := ReaderWrapper4{
		roTx: histTx,
		ac:   agg.MakeContext(),
	}

	switch readDomain {
	case "account":
		for _, addr := range addrs {
			acc, err := r.ReadAccountData(libcommon.BytesToAddress(addr))
			if err != nil {
				logger.Error("failed to read account", "addr", addr, "err", err)
				continue
			}
			fmt.Printf("%x: nonce=%d balance=%d code=%x root=%x\n", addr, acc.Nonce, acc.Balance.Uint64(), acc.CodeHash, acc.Root)
		}
	case "storage":
		for _, addr := range addrs {
			a, s := libcommon.BytesToAddress(addr[:length.Addr]), libcommon.BytesToHash(addr[length.Addr:])
			st, err := r.ReadAccountStorage(a, 0, &s)
			if err != nil {
				logger.Error("failed to read storage", "addr", a.String(), "key", s.String(), "err", err)
				continue
			}
			fmt.Printf("%s %s -> %x\n", a.String(), s.String(), st)
		}
	case "code":
		for _, addr := range addrs {
			code, err := r.ReadAccountCode(libcommon.BytesToAddress(addr), 0, libcommon.Hash{})
			if err != nil {
				logger.Error("failed to read code", "addr", addr, "err", err)
				continue
			}
			fmt.Printf("%s: %x\n", addr, code)
		}
	}
	return nil
}

// Implements StateReader and StateWriter
type ReaderWrapper4 struct {
	roTx kv.Tx
	ac   *libstate.AggregatorContext
}

type WriterWrapper4 struct {
	w *libstate.Aggregator
}

func (rw *ReaderWrapper4) SetTx(roTx kv.Tx, ctx *libstate.AggregatorContext) {
	rw.roTx = roTx
	rw.ac.Close()
	rw.ac = ctx
}

func (rw *ReaderWrapper4) ReadAccountData(address libcommon.Address) (*accounts.Account, error) {
	enc, err := rw.ac.ReadAccountData(address.Bytes(), rw.roTx)
	if err != nil {
		return nil, err
	}
	if len(enc) == 0 {
		return nil, nil
	}
	var a accounts.Account
	if err := accounts.DeserialiseV3(&a, enc); err != nil {
		return nil, err
	}
	return &a, nil
}

func (rw *ReaderWrapper4) ReadAccountStorage(address libcommon.Address, incarnation uint64, key *libcommon.Hash) ([]byte, error) {
	enc, err := rw.ac.ReadAccountStorage(address.Bytes(), key.Bytes(), rw.roTx)
	if err != nil {
		return nil, err
	}
	if enc == nil {
		return nil, nil
	}
	if len(enc) == 1 && enc[0] == 0 {
		return nil, nil
	}
	return enc, nil
}

func (rw *ReaderWrapper4) ReadAccountCode(address libcommon.Address, incarnation uint64, codeHash libcommon.Hash) ([]byte, error) {
	return rw.ac.ReadAccountCode(address.Bytes(), rw.roTx)
}

func (rw *ReaderWrapper4) ReadAccountCodeSize(address libcommon.Address, incarnation uint64, codeHash libcommon.Hash) (int, error) {
	return rw.ac.ReadAccountCodeSize(address.Bytes(), rw.roTx)
}

func (rw *ReaderWrapper4) ReadAccountIncarnation(address libcommon.Address) (uint64, error) {
	return 0, nil
}

func (ww *WriterWrapper4) UpdateAccountData(address libcommon.Address, original, account *accounts.Account) error {
	value := accounts.SerialiseV3(account)
	if err := ww.w.UpdateAccountData(address.Bytes(), value); err != nil {
		return err
	}
	return nil
}

func (ww *WriterWrapper4) UpdateAccountCode(address libcommon.Address, incarnation uint64, codeHash libcommon.Hash, code []byte) error {
	if err := ww.w.UpdateAccountCode(address.Bytes(), code); err != nil {
		return err
	}
	return nil
}

func (ww *WriterWrapper4) DeleteAccount(address libcommon.Address, original *accounts.Account) error {
	if err := ww.w.DeleteAccount(address.Bytes()); err != nil {
		return err
	}
	return nil
}

func (ww *WriterWrapper4) WriteAccountStorage(address libcommon.Address, incarnation uint64, key *libcommon.Hash, original, value *uint256.Int) error {
	if err := ww.w.WriteAccountStorage(address.Bytes(), key.Bytes(), value.Bytes()); err != nil {
		return err
	}
	return nil
}

func (ww *WriterWrapper4) CreateContract(address libcommon.Address) error {
	return nil
}

type stat4 struct {
	prevBlock    uint64
	blockNum     uint64
	hits         uint64
	misses       uint64
	hitMissRatio float64
	blockSpeed   float64
	txSpeed      float64
	prevTxNum    uint64
	txNum        uint64
	prevTime     time.Time
	mem          runtime.MemStats
	startedAt    time.Time
}

func (s *stat4) print(aStats libstate.FilesStats, logger log.Logger) {
	totalFiles := aStats.FilesCount
	totalDatSize := aStats.DataSize
	totalIdxSize := aStats.IdxSize

	logger.Info("Progress", "block", s.blockNum, "blk/s", s.blockSpeed, "tx", s.txNum, "txn/s", s.txSpeed, "state files", totalFiles,
		"total dat", libcommon.ByteCount(totalDatSize), "total idx", libcommon.ByteCount(totalIdxSize),
		"hit ratio", s.hitMissRatio, "hits+misses", s.hits+s.misses,
		"alloc", libcommon.ByteCount(s.mem.Alloc), "sys", libcommon.ByteCount(s.mem.Sys),
	)
}

func (s *stat4) delta(blockNum, txNum uint64) *stat4 {
	currentTime := time.Now()
	dbg.ReadMemStats(&s.mem)

	interval := currentTime.Sub(s.prevTime).Seconds()
	s.blockNum = blockNum
	s.blockSpeed = float64(s.blockNum-s.prevBlock) / interval
	s.txNum = txNum
	s.txSpeed = float64(s.txNum-s.prevTxNum) / interval
	s.prevBlock = blockNum
	s.prevTxNum = txNum
	s.prevTime = currentTime
	if s.startedAt.IsZero() {
		s.startedAt = currentTime
	}

	total := s.hits + s.misses
	if total > 0 {
		s.hitMissRatio = float64(s.hits) / float64(total)
	}
	return s
}