Merge pull request #23 from ravi0131/payment-channel-ckb

Payment channel ckb

payment-channel-ckb/.gitignore

@@ -0,0 +1,28 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# log files
+*.log
+
+perun-ckb-demo
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+devnet/accounts
+devnet/data
+devnet/specs
+devnet/ckb-miner.toml
+devnet/ckb.toml
+devnet/default.db-options
+devnet/system_scripts
+.vscode/

payment-channel-ckb/.gitmodules

@@ -0,0 +1,3 @@
+[submodule "devnet/contracts"]
+	path = devnet/contracts
+	url = [email protected]:perun-network/perun-ckb-contract

payment-channel-ckb/client/balances.go

@@ -0,0 +1,89 @@
+package client
+
+import (
+	"context"
+	"encoding/binary"
+	"fmt"
+	"log"
+	"math"
+	"math/big"
+	"strconv"
+	"time"
+
+	"github.com/nervosnetwork/ckb-sdk-go/v2/indexer"
+	"github.com/nervosnetwork/ckb-sdk-go/v2/types"
+	"perun.network/perun-ckb-backend/wallet/address"
+)
+
+type BalanceExtractor func(*indexer.LiveCell) *big.Int
+
+func ckbBalanceExtractor(cell *indexer.LiveCell) *big.Int {
+	return new(big.Int).SetUint64(cell.Output.Capacity)
+}
+
+func sudtBalanceExtractor(cell *indexer.LiveCell) *big.Int {
+	if len(cell.OutputData) != 16 {
+		return big.NewInt(0)
+	}
+	return new(big.Int).SetUint64(binary.LittleEndian.Uint64(cell.OutputData))
+}
+
+func (p *PaymentClient) PollBalances() {
+	defer log.Println("PollBalances: stopped")
+	pollingInterval := time.Second
+	searchKey := &indexer.SearchKey{
+		Script:           address.AsParticipant(p.Account.Address()).PaymentScript,
+		ScriptType:       types.ScriptTypeLock,
+		ScriptSearchMode: types.ScriptSearchModeExact,
+		Filter:           nil,
+		WithData:         true,
+	}
+	log.Println("PollBalances")
+	updateBalance := func() {
+		ctx, _ := context.WithTimeout(context.Background(), pollingInterval)
+
+		cells, err := p.rpcClient.GetCells(ctx, searchKey, indexer.SearchOrderDesc, math.MaxUint32, "")
+		if err != nil {
+			log.Println("balance poll error: ", err)
+			return
+		}
+		ckbBalance := big.NewInt(0)
+		sudtBalance := big.NewInt(0)
+		for _, cell := range cells.Objects {
+			ckbBalance = new(big.Int).Add(ckbBalance, ckbBalanceExtractor(cell))
+			sudtBalance = new(big.Int).Add(sudtBalance, sudtBalanceExtractor(cell))
+		}
+
+		p.balanceMutex.Lock()
+		if ckbBalance.Cmp(p.balance) != 0 || sudtBalance.Cmp(p.sudtBalance) != 0 {
+			// Update ckb balance.
+			p.balance = ckbBalance
+			//ckbBal := p.balance.Int64()
+
+			// Update sudt balance.
+			p.sudtBalance = sudtBalance
+
+			p.balanceMutex.Unlock()
+			//p.NotifyAllBalance(ckbBal) // TODO: Update demo tui to allow for big.Int balances
+		} else {
+			p.balanceMutex.Unlock()
+		}
+	}
+	updateBalance()
+	//return "CKbytes: " + p.balance.String() + ", SUDT: " + p.sudtBalance.String()
+	/*
+		// Poll the balance every 5 seconds.
+		for {
+			updateBalance()
+			time.Sleep(pollingInterval)
+		}
+	*/
+}
+
+func FormatBalance(ckbBal, sudtBal *big.Int) string {
+	log.Printf("balances: ckb = %s || sudt = %s", ckbBal.String(), sudtBal.String())
+	balCKByte, _ := ShannonToCKByte(ckbBal).Float64()
+	return fmt.Sprintf("[green]%s\t[yellow]%s[white]",
+		strconv.FormatFloat(balCKByte, 'f', 2, 64)+" CKByte",
+		fmt.Sprintf("%v", sudtBal.Int64())+" SUDT")
+}

payment-channel-ckb/client/channel.go

@@ -0,0 +1,91 @@
+package client
+
+import (
+	"context"
+	"fmt"
+	"math/big"
+
+	"perun.network/go-perun/channel"
+	"perun.network/go-perun/client"
+)
+
+type PaymentChannel struct {
+	ch     *client.Channel
+	assets []channel.Asset
+}
+
+// newPaymentChannel creates a new payment channel.
+func newPaymentChannel(ch *client.Channel, assets []channel.Asset) *PaymentChannel {
+	return &PaymentChannel{
+		ch:     ch,
+		assets: assets,
+	}
+}
+
+func (c PaymentChannel) State() *channel.State {
+	return c.ch.State().Clone()
+}
+
+func (c PaymentChannel) SendPayment(amounts map[channel.Asset]float64) {
+	// Transfer the given amount from us to peer.
+	// Use UpdateBy to update the channel state.
+	err := c.ch.Update(context.TODO(), func(state *channel.State) {
+		actor := c.ch.Idx()
+		peer := 1 - actor
+		//fmt.Println("Send payment handler called")
+		for a, amount := range amounts {
+			fmt.Println(a)
+			fmt.Println(amount)
+			if amount < 0 {
+				continue
+			}
+			/*
+				switch a := a.(type) {
+				case *asset.Asset:
+					if a.IsCKBytes {
+						fmt.Println("inside condition isCKBytes")
+						shannonAmount := CKByteToShannon(big.NewFloat(amount))
+						state.Allocation.TransferBalance(actor, peer, a, shannonAmount)
+					} else {
+						fmt.Println("inside if conditional !isCKBytes")
+						intAmount := new(big.Int).SetUint64(uint64(amount))
+						state.Allocation.TransferBalance(actor, peer, a, intAmount)
+					}
+				}
+			*/
+
+			shannonAmount := CKByteToShannon(big.NewFloat(amount))
+			state.Allocation.TransferBalance(actor, peer, a, shannonAmount)
+
+		}
+
+	})
+	if err != nil {
+		panic(err)
+	}
+	if err != nil {
+		panic(err) // We panic on error to keep the code simple.
+	}
+}
+
+// Settle settles the payment channel and withdraws the funds.
+func (c PaymentChannel) Settle() {
+	// Finalize the channel to enable fast settlement.
+	if !c.ch.State().IsFinal {
+		err := c.ch.Update(context.TODO(), func(state *channel.State) {
+			state.IsFinal = true
+		})
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	// Settle concludes the channel and withdraws the funds.
+	err := c.ch.Settle(context.TODO())
+	if err != nil {
+		panic(err)
+	}
+
+	// Close frees up channel resources.
+	c.ch.Close()
+}