package geyser

import (
	"context"
	"crypto/x509"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"time"

	solana2 "github.com/gagliardetto/solana-go"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"
	"google.golang.org/grpc/credentials/insecure"
	"google.golang.org/grpc/keepalive"
	"google.golang.org/grpc/metadata"

	types "github.com/thloyi/pump-parser"
	pb "github.com/thloyi/pump-parser/example/geyser/proto"
)

type Handler interface {
	HandleMessage(rawTx *types.RawTx)
}

var kacp = keepalive.ClientParameters{
	Time:                10 * time.Second, // send pings every 10 seconds if there is no activity
	Timeout:             time.Second,      // wait 1 second for ping ack before considering the connection dead
	PermitWithoutStream: true,             // send pings even without active streams
}

type Client struct {
	ch              chan SubscriptionMessage
	endpoint        string
	conn            *grpc.ClientConn
	ctx             context.Context
	lastReceiveTime time.Time
	backoffFactor   float64

	subscription *pb.SubscribeRequest
	subStatus    bool

	leastBlock BlockInfo

	firstMessage bool

	handler Handler
}

func NewClientWithPumpSwap(endpoint string, ch chan SubscriptionMessage) *Client {
	var subscription pb.SubscribeRequest

	var failed = false
	var vote = false
	subscription.Transactions = make(map[string]*pb.SubscribeRequestFilterTransactions)
	subscription.Transactions["transactions_sub"] = &pb.SubscribeRequestFilterTransactions{
		Failed: &failed,
		Vote:   &vote,
	}

	subscription.Transactions["transactions_sub"].AccountInclude = []string{
		"pAMMBay6oceH9fJKBRHGP5D4bD4sWpmSwMn52FMfXEA", //Pump AMM
		"6EF8rrecthR5Dkzon8Nwu78hRvfCKubJ14M5uBEwF6P", //Pump
	}
	subscription.BlocksMeta = make(map[string]*pb.SubscribeRequestFilterBlocksMeta)
	subscription.BlocksMeta["block_meta"] = &pb.SubscribeRequestFilterBlocksMeta{}

	c := &Client{
		backoffFactor:   1.5,
		ch:              ch,
		endpoint:        endpoint,
		lastReceiveTime: time.Now(),
		subStatus:       false,
		subscription:    &subscription,
	}
	c.handler = NewPumpHandler(func(tx *types.Tx, tx2 *types.RawTx) {
		c.sendTx(tx, tx2)
	})
	return c
}

func NewClientWithLaunchLab(endpoint string, ch chan SubscriptionMessage) *Client {
	var subscription pb.SubscribeRequest

	var failed = false
	var vote = false
	subscription.Transactions = make(map[string]*pb.SubscribeRequestFilterTransactions)
	subscription.Transactions["transactions_sub"] = &pb.SubscribeRequestFilterTransactions{
		Failed: &failed,
		Vote:   &vote,
	}

	subscription.Transactions["transactions_sub"].AccountInclude = []string{
		"LanMV9sAd7wArD4vJFi2qDdfnVhFxYSUg6eADduJ3uj",  //LaunchLab
		"CPMMoo8L3F4NbTegBCKVNunggL7H1ZpdTHKxQB5qKP1C", //CPMM
		//"675kPX9MHTjS2zt1qfr1NYHuzeLXfQM9H24wFSUt1Mp8", //V4
	}
	subscription.BlocksMeta = make(map[string]*pb.SubscribeRequestFilterBlocksMeta)
	subscription.BlocksMeta["block_meta"] = &pb.SubscribeRequestFilterBlocksMeta{}

	c := &Client{
		backoffFactor:   1.5,
		ch:              ch,
		endpoint:        endpoint,
		lastReceiveTime: time.Now(),
		subStatus:       false,
		subscription:    &subscription,
	}
	c.handler = NewPumpHandler(func(tx *types.Tx, tx2 *types.RawTx) {
		c.sendTx(tx, tx2)
	})
	return c
}

func RunLoopWithReConnect(ctx context.Context, endpoint, program string, ch chan SubscriptionMessage) {
	var client *Client
	if program == types.SolProgramRaydiumLaunchLab {
		client = NewClientWithLaunchLab(endpoint, ch)
	} else {
		client = NewClientWithPumpSwap(endpoint, ch)
	}
	for {
		select {
		case <-ctx.Done():
			log.Println("Context done, exiting loop")
			return
		default:
		}
		err := client.Connect(ctx)
		if err != nil {
			log.Printf("Failed to connect: %v", err)
			time.Sleep(5 * time.Second)
			continue
		}
		// should not reach here, because Connect will block
		panic("geyser already connected, waiting for messages...")
	}
}

func (c *Client) SetSubscribe(subscription *pb.SubscribeRequest) {
	c.subscription = subscription
}

func (c *Client) Connect(ctx context.Context) error {

	c.ctx = ctx
	if c.conn == nil {
		// 连接到 geyser
		conn, err := c.grpcConnect(c.endpoint, true)
		if err != nil {
			return err
		}
		c.conn = conn
	}

	if c.subStatus {
		return nil // 已经订阅了
	}
	// 订阅交易
	err := c.grpcSubscribe(ctx, c.conn)
	if err != nil {
		if c.conn != nil {
			c.conn.Close()
		}
		c.conn = nil
		c.subStatus = false
		log.Printf("Failed to subscribe: %v", err)
		return err
	}

	return nil
}

func (c *Client) grpcConnect(address string, plaintext bool) (*grpc.ClientConn, error) {
	var opts []grpc.DialOption
	if plaintext {
		opts = append(opts, grpc.WithTransportCredentials(insecure.NewCredentials()))
	} else {
		pool, _ := x509.SystemCertPool()
		creds := credentials.NewClientTLSFromCert(pool, "")
		opts = append(opts, grpc.WithTransportCredentials(creds))
	}

	opts = append(opts, grpc.WithKeepaliveParams(kacp))

	log.Println("Starting grpc client, connecting to", address)
	conn, err := grpc.NewClient(address, opts...)
	if err != nil {
		return nil, fmt.Errorf("fail to dial: %v", err)
	}

	return conn, nil
}

func (c *Client) grpcSubscribe(ctx context.Context, conn *grpc.ClientConn) error {
	var err error
	client := pb.NewGeyserClient(conn)

	//subscription.Transactions["transactions_sub"].AccountExclude = transactionsAccountsExclude

	subscriptionJson, err := json.Marshal(c.subscription)
	if err != nil {
		log.Printf("Failed to marshal subscription request: %v", subscriptionJson)
		return err
	}
	log.Printf("Subscription request: %s", string(subscriptionJson))

	// Set up the subscription request
	//if *token != "" {
	//	md := metadata.New(map[string]string{"x-token": *token})
	//	ctx = metadata.NewOutgoingContext(ctx, md)
	//}
	md := metadata.New(map[string]string{"x-token": "5adcf1f9-5719-43d1-bf3f-c2d4e1e5f94d"})
	ctx = metadata.NewOutgoingContext(ctx, md)

	stream, err := client.Subscribe(ctx)
	if err != nil {
		return err
	}
	err = stream.Send(c.subscription)
	if err != nil {
		return err
	}
	c.subStatus = true
	c.firstMessage = true
	for {
		resp, err := stream.Recv()

		if err == io.EOF {
			return err
		}
		if err != nil {
			return fmt.Errorf("error occurred in receiving update: %s", err)
		}

		txn := resp.GetTransaction()
		if txn == nil {
			blockMeta := resp.GetBlockMeta()
			if blockMeta != nil && c.ch != nil {
				c.sendBlock(blockMeta)
			}
			continue
		}
		rawTx, err := ConvertYellowstoneGrpcTransactionToSolanaTransaction(txn, resp.GetCreatedAt().Seconds)
		if err != nil {
			log.Printf("Failed to convert transaction: %v", err)
			continue
		}
		c.handler.HandleMessage(rawTx)
	}
}

func (c *Client) computeDelay(slot uint64) int64 {
	if c.leastBlock.Slot == 0 {
		return 0
	}
	if slot < c.leastBlock.Slot {
		return 0
	}
	delay := time.Now().Unix() - c.leastBlock.BlockTime - (4 * int64(slot-c.leastBlock.Slot) / 10)
	return delay
}

func (c *Client) sendTx(t *types.Tx, tx *types.RawTx) {
	c.ch <- SubscriptionMessage{
		Reconnect:           c.firstMessage,
		EstimateDelaySecond: c.computeDelay(tx.Slot),
		Block:               nil,
		Tx:                  t,
		RawTx:               tx,
	}
	c.firstMessage = false
}

func (c *Client) sendBlock(blockMeta *pb.SubscribeUpdateBlockMeta) {
	c.leastBlock.Slot = blockMeta.GetSlot()
	c.leastBlock.BlockTime = blockMeta.GetBlockTime().Timestamp
	c.leastBlock.BlockHash = blockMeta.Blockhash
	c.leastBlock.Height = blockMeta.BlockHeight.BlockHeight
	c.ch <- SubscriptionMessage{
		EstimateDelaySecond: time.Now().Unix() - blockMeta.GetBlockTime().Timestamp,
		Reconnect:           c.firstMessage,
		Block: &BlockInfo{
			Slot:      c.leastBlock.Slot,
			BlockTime: c.leastBlock.BlockTime,
			BlockHash: c.leastBlock.BlockHash,
			Height:    c.leastBlock.Height,
		},
		Tx:    nil,
		RawTx: nil,
	}
	c.firstMessage = false
}

func ConvertYellowstoneGrpcTransactionToSolanaTransaction(y *pb.SubscribeUpdateTransaction, created int64) (*types.RawTx, error) {
	sTx := &types.RawTx{
		BlockTime:        created,
		Slot:             y.Slot,
		IndexWithinBlock: int64(y.Transaction.Index),
		Meta: types.Meta{
			Err:               nil,
			Fee:               0,
			InnerInstructions: nil,
			LoadedAddresses:   types.LoadedAddresses{},
			LogMessages:       nil,
			PostBalances:      nil,
			PostTokenBalances: nil,
			PreBalances:       nil,
			PreTokenBalances:  nil,
			Rewards:           nil,
		},
		//Transaction: types.Transaction{
		//	Message: types.Message{
		//		AccountKeys:         nil,
		//		AddressTableLookups: nil,
		//		Header:              types.Header{},
		//		Instructions:        nil,
		//		RecentBlockHash:     "",
		//	},
		//	Signatures: nil,
		//},
		//Version:          nil,
	}
	meta := y.Transaction.GetMeta()
	yTx := y.Transaction.Transaction

	if meta.Err != nil && len(meta.Err.GetErr()) > 0 {
		// If the transaction has an error, we set the error in the Meta
		transError, err := DecodeTransactionError(meta.Err.GetErr())
		if err != nil {
			sTx.Meta.Err = err
		} else {
			sTx.Meta.Err = transError
		}
		// sTx.Meta.Err = meta.Err.GetErr()
	}
	sTx.Meta.Fee = meta.Fee
	//sTx.Meta.InnerInstructions = meta.InnerInstructions

	for _, innerInstr := range meta.InnerInstructions {
		var instrs []types.Instruction
		for _, instr := range innerInstr.Instructions {
			instrs = append(instrs, types.Instruction{
				ProgramIDIndex: int(instr.ProgramIdIndex),
				Accounts: func() []int {
					var out []int
					for i := range instr.Accounts {
						out = append(out, int(instr.Accounts[i]))
					}
					return out
				}(),
				Data: instr.Data,
			})
		}
		sTx.Meta.InnerInstructions = append(sTx.Meta.InnerInstructions, types.InnerInstructions{
			Index:        int(innerInstr.Index),
			Instructions: instrs,
		})
	}
	sTx.Meta.LogMessages = meta.LogMessages
	sTx.Meta.PostBalances = meta.PostBalances
	sTx.Meta.PostTokenBalances = grpcTokenBalance(meta.PostTokenBalances)
	sTx.Meta.PreBalances = meta.PreBalances
	sTx.Meta.PreTokenBalances = grpcTokenBalance(meta.PreTokenBalances)
	sTx.Meta.Rewards = nil
	sTx.Meta.LoadedAddresses.Readonly = byteSlicesToKeySlices(meta.LoadedReadonlyAddresses)
	sTx.Meta.LoadedAddresses.Writable = byteSlicesToKeySlices(meta.LoadedWritableAddresses)

	// copy signatures
	for i := range yTx.Signatures {
		sTx.Transaction.Signatures = append(sTx.Transaction.Signatures, solana2.SignatureFromBytes(yTx.Signatures[i]))
	}
	// copy message
	sTx.Transaction.Message = types.Message{
		RecentBlockHash: solana2.HashFromBytes(yTx.Message.RecentBlockhash).String(),
	}
	// copy message.AccountKeys
	//stopAt := len(yTx.Message.AccountKeys) - sTx.Message.NumLookups()
	stopAt := len(yTx.Message.AccountKeys)
	for accIndex, acc := range yTx.Message.AccountKeys {
		sTx.Transaction.Message.AccountKeys = append(sTx.Transaction.Message.AccountKeys, solana2.PublicKeyFromBytes(acc))
		if accIndex == stopAt-1 {
			break
		}
	}
	// copy message.Header
	sTx.Transaction.Message.Header = types.Header{
		NumRequiredSignatures:       int(yTx.Message.Header.NumRequiredSignatures),
		NumReadonlySignedAccounts:   int(yTx.Message.Header.NumReadonlySignedAccounts),
		NumReadonlyUnsignedAccounts: int(yTx.Message.Header.NumReadonlyUnsignedAccounts),
	}

	// copy message.versioned
	if yTx.Message.Versioned {
		sTx.Version = solana2.MessageVersionV0
	} else {
		sTx.Version = solana2.MessageVersionLegacy
	}

	// copy address table lookups
	{
		tables := map[solana2.PublicKey]solana2.PublicKeySlice{}
		writable := byteSlicesToKeySlices(meta.LoadedWritableAddresses)
		readonly := byteSlicesToKeySlices(meta.LoadedReadonlyAddresses)
		for _, addr := range yTx.Message.AddressTableLookups {
			sTx.Transaction.Message.AddressTableLookups = append(sTx.Transaction.Message.AddressTableLookups, solana2.MessageAddressTableLookup{
				AccountKey:      solana2.PublicKeyFromBytes(addr.AccountKey),
				WritableIndexes: addr.WritableIndexes,
				ReadonlyIndexes: addr.ReadonlyIndexes,
			})
			numTakeWritable := len(addr.WritableIndexes)
			numTakeReadonly := len(addr.ReadonlyIndexes)
			tableKey := solana2.PublicKeyFromBytes(addr.AccountKey)
			{
				// now need to rebuild the address table taking into account the indexes, and put the keys into the tables
				maxIndex := 0
				for _, indexB := range addr.WritableIndexes {
					index := int(indexB)
					if index > maxIndex {
						maxIndex = index
					}
				}
				for _, indexB := range addr.ReadonlyIndexes {
					index := int(indexB)
					if index > maxIndex {
						maxIndex = index
					}
				}
				tables[tableKey] = make([]solana2.PublicKey, maxIndex+1)
			}
			if numTakeWritable > 0 {
				writableForTable := writable[:numTakeWritable]
				for i, indexB := range addr.WritableIndexes {
					index := int(indexB)
					tables[tableKey][index] = writableForTable[i]
				}
				writable = writable[numTakeWritable:]
			}
			if numTakeReadonly > 0 {
				readableForTable := readonly[:numTakeReadonly]
				for i, indexB := range addr.ReadonlyIndexes {
					index := int(indexB)
					tables[tableKey][index] = readableForTable[i]
				}
				readonly = readonly[numTakeReadonly:]
			}

		}
	}

	// copy instructions
	for _, instr := range yTx.Message.Instructions {
		sTx.Transaction.Message.Instructions = append(sTx.Transaction.Message.Instructions, types.Instruction{
			ProgramIDIndex: int(instr.ProgramIdIndex),
			Accounts: func() []int {
				var out []int
				for i := range instr.Accounts {
					out = append(out, int(instr.Accounts[i]))
				}
				return out
			}(),
			Data: instr.Data,
		})
	}

	// resolve the lookups
	//{
	//	if sTx.Transaction.Message.IsVersioned() {
	//		// only versioned transactions have address table lookups
	//		err := sTx.Transaction.Message.ResolveLookups()
	//		if err != nil {
	//			return sTx, fmt.Errorf("failed to resolve lookups: %w", err)
	//		}
	//	}
	//}

	return sTx, nil
}

func byteSlicesToKeySlices(keys [][]byte) []solana2.PublicKey {
	var out []solana2.PublicKey
	for _, key := range keys {
		var k solana2.PublicKey
		copy(k[:], key)
		out = append(out, k)
	}
	return out
}

func grpcTokenBalance(src []*pb.TokenBalance) []types.TokenBalance {
	out := make([]types.TokenBalance, len(src))
	for i, tb := range src {
		var (
			mintAccount      solana2.PublicKey
			ownerAccount     solana2.PublicKey
			programIDAccount solana2.PublicKey
		)

		if tb.Mint != "" {
			mintAccount, _ = solana2.PublicKeyFromBase58(tb.Mint)
		}
		if tb.Owner != "" {
			ownerAccount, _ = solana2.PublicKeyFromBase58(tb.Owner)
		}
		if tb.ProgramId != "" {
			programIDAccount, _ = solana2.PublicKeyFromBase58(tb.ProgramId)
		}

		out[i] = types.TokenBalance{
			AccountIndex:     int(tb.AccountIndex),
			MintAccount:      mintAccount,
			OwnerAccount:     &ownerAccount,
			ProgramIDAccount: programIDAccount,
			Mint:             tb.Mint,
			Owner:            tb.Owner,
			ProgramID:        tb.ProgramId,
			UITokenAmount: types.UITokenAmount{
				Amount:         tb.UiTokenAmount.Amount,
				Decimals:       uint64(tb.UiTokenAmount.Decimals),
				UIAmount:       tb.UiTokenAmount.UiAmount,
				UIAmountString: tb.UiTokenAmount.UiAmountString,
			},
		}
	}
	return out
}