cli: implement NEP5 balance querying

cli/wallet/nep5.go

@@ -1,8 +1,10 @@
 package wallet
 
 import (
+	"errors"
 	"fmt"
 
+	"github.com/nspcc-dev/neo-go/pkg/encoding/address"
 	"github.com/nspcc-dev/neo-go/pkg/rpc/client"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
@@ -11,6 +13,25 @@ import (
 
 func newNEP5Commands() []cli.Command {
 	return []cli.Command{
+		{
+			Name:      "balance",
+			Usage:     "get address balance",
+			UsageText: "balance --path <path> --rpc <node> --addr <addr> [--token <hash-or-name>]",
+			Action:    getNEP5Balance,
+			Flags: []cli.Flag{
+				walletPathFlag,
+				rpcFlag,
+				timeoutFlag,
+				cli.StringFlag{
+					Name:  "addr",
+					Usage: "Address to use",
+				},
+				cli.StringFlag{
+					Name:  "token",
+					Usage: "Token to use",
+				},
+			},
+		},
 		{
 			Name:      "import",
 			Usage:     "import NEP5 token to a wallet",
@@ -28,6 +49,99 @@ func newNEP5Commands() []cli.Command {
 	}
 }
 
+func getNEP5Balance(ctx *cli.Context) error {
+	wall, err := openWallet(ctx.String("path"))
+	if err != nil {
+		return cli.NewExitError(err, 1)
+	}
+	defer wall.Close()
+
+	addr := ctx.String("addr")
+	addrHash, err := address.StringToUint160(addr)
+	if err != nil {
+		return cli.NewExitError(fmt.Errorf("invalid address: %v", err), 1)
+	}
+	acc := wall.GetAccount(addrHash)
+	if acc == nil {
+		return cli.NewExitError(fmt.Errorf("can't find account for the address: %s", addr), 1)
+	}
+
+	gctx, cancel := getGoContext(ctx)
+	defer cancel()
+
+	c, err := client.New(gctx, ctx.String("rpc"), client.Options{})
+	if err != nil {
+		return cli.NewExitError(err, 1)
+	}
+
+	var token *wallet.Token
+	name := ctx.String("token")
+	if name != "" {
+		token, err = getMatchingToken(wall, name)
+		if err != nil {
+			token, err = getMatchingTokenRPC(c, addrHash, name)
+			if err != nil {
+				return cli.NewExitError(err, 1)
+			}
+		}
+	}
+
+	balances, err := c.GetNEP5Balances(addrHash)
+	if err != nil {
+		return cli.NewExitError(err, 1)
+	}
+
+	for i := range balances.Balances {
+		asset := balances.Balances[i].Asset
+		if name != "" && !token.Hash.Equals(asset) {
+			continue
+		}
+		fmt.Printf("TokenHash: %s\n", asset)
+		fmt.Printf("\tAmount : %s\n", balances.Balances[i].Amount)
+		fmt.Printf("\tUpdated: %d\n", balances.Balances[i].LastUpdated)
+	}
+	return nil
+}
+
+func getMatchingToken(w *wallet.Wallet, name string) (*wallet.Token, error) {
+	return getMatchingTokenAux(func(i int) *wallet.Token {
+		return w.Extra.Tokens[i]
+	}, len(w.Extra.Tokens), name)
+}
+
+func getMatchingTokenRPC(c *client.Client, addr util.Uint160, name string) (*wallet.Token, error) {
+	bs, err := c.GetNEP5Balances(addr)
+	if err != nil {
+		return nil, err
+	}
+	get := func(i int) *wallet.Token {
+		t, _ := c.NEP5TokenInfo(bs.Balances[i].Asset)
+		return t
+	}
+	return getMatchingTokenAux(get, len(bs.Balances), name)
+}
+
+func getMatchingTokenAux(get func(i int) *wallet.Token, n int, name string) (*wallet.Token, error) {
+	var token *wallet.Token
+	var count int
+	for i := 0; i < n; i++ {
+		t := get(i)
+		if t != nil && (t.Name == name || t.Symbol == name || t.Address == name || t.Hash.StringLE() == name) {
+			if count == 1 {
+				printTokenInfo(token)
+				printTokenInfo(t)
+				return nil, errors.New("multiple matching tokens found")
+			}
+			count++
+			token = t
+		}
+	}
+	if count == 0 {
+		return nil, errors.New("token was not found")
+	}
+	return token, nil
+}
+
 func importNEP5Token(ctx *cli.Context) error {
 	wall, err := openWallet(ctx.String("path"))
 	if err != nil {