use keyer.Keyer in most places instead of raw bunkers and plaintext keys, simplifies the code a little at the cost of some abstraction but I think it's strictly good this time.

helpers_key.go

@@ -0,0 +1,160 @@
+package main
+
+import (
+	"context"
+	"encoding/hex"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/chzyer/readline"
+	"github.com/fatih/color"
+	"github.com/fiatjaf/cli/v3"
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/keyer"
+	"github.com/nbd-wtf/go-nostr/nip19"
+	"github.com/nbd-wtf/go-nostr/nip46"
+	"github.com/nbd-wtf/go-nostr/nip49"
+)
+
+var defaultKeyFlags = []cli.Flag{
+	&cli.StringFlag{
+		Name:        "sec",
+		Usage:       "secret key to sign the event, as nsec, ncryptsec or hex, or a bunker URL",
+		DefaultText: "the key '1'",
+		Aliases:     []string{"connect"},
+		Category:    CATEGORY_SIGNER,
+	},
+	&cli.BoolFlag{
+		Name:     "prompt-sec",
+		Usage:    "prompt the user to paste a hex or nsec with which to sign the event",
+		Category: CATEGORY_SIGNER,
+	},
+	&cli.StringFlag{
+		Name:        "connect-as",
+		Usage:       "private key to when communicating with the bunker given on --connect",
+		DefaultText: "a random key",
+		Category:    CATEGORY_SIGNER,
+	},
+}
+
+func gatherKeyerFromArguments(ctx context.Context, c *cli.Command) (keyer.Keyer, error) {
+	key, bunker, err := gatherSecretKeyOrBunkerFromArguments(ctx, c)
+	if err != nil {
+		return nil, err
+	}
+
+	var kr keyer.Keyer
+	if bunker != nil {
+		kr = keyer.NewBunkerSignerFromBunkerClient(bunker)
+	} else {
+		kr = keyer.NewPlainKeySigner(key)
+	}
+
+	return kr, nil
+}
+
+func gatherSecretKeyOrBunkerFromArguments(ctx context.Context, c *cli.Command) (string, *nip46.BunkerClient, error) {
+	var err error
+
+	sec := c.String("sec")
+	if strings.HasPrefix(sec, "bunker://") {
+		// it's a bunker
+		bunkerURL := sec
+		clientKey := c.String("connect-as")
+		if clientKey != "" {
+			clientKey = strings.Repeat("0", 64-len(clientKey)) + clientKey
+		} else {
+			clientKey = nostr.GeneratePrivateKey()
+		}
+		bunker, err := nip46.ConnectBunker(ctx, clientKey, bunkerURL, nil, func(s string) {
+			fmt.Fprintf(color.Error, color.CyanString("[nip46]: open the following URL: %s"), s)
+		})
+		return "", bunker, err
+	}
+
+	// take private from flags, environment variable or default to 1
+	if sec == "" {
+		if key, ok := os.LookupEnv("NOSTR_SECRET_KEY"); ok {
+			sec = key
+		} else {
+			sec = "0000000000000000000000000000000000000000000000000000000000000001"
+		}
+	}
+
+	if c.Bool("prompt-sec") {
+		if isPiped() {
+			return "", nil, fmt.Errorf("can't prompt for a secret key when processing data from a pipe, try again without --prompt-sec")
+		}
+		sec, err = askPassword("type your secret key as ncryptsec, nsec or hex: ", nil)
+		if err != nil {
+			return "", nil, fmt.Errorf("failed to get secret key: %w", err)
+		}
+	}
+
+	if strings.HasPrefix(sec, "ncryptsec1") {
+		sec, err = promptDecrypt(sec)
+		if err != nil {
+			return "", nil, fmt.Errorf("failed to decrypt: %w", err)
+		}
+	} else if bsec, err := hex.DecodeString(leftPadKey(sec)); err == nil {
+		sec = hex.EncodeToString(bsec)
+	} else if prefix, hexvalue, err := nip19.Decode(sec); err != nil {
+		return "", nil, fmt.Errorf("invalid nsec: %w", err)
+	} else if prefix == "nsec" {
+		sec = hexvalue.(string)
+	}
+
+	if ok := nostr.IsValid32ByteHex(sec); !ok {
+		return "", nil, fmt.Errorf("invalid secret key")
+	}
+
+	return sec, nil, nil
+}
+
+func promptDecrypt(ncryptsec string) (string, error) {
+	for i := 1; i < 4; i++ {
+		var attemptStr string
+		if i > 1 {
+			attemptStr = fmt.Sprintf(" [%d/3]", i)
+		}
+		password, err := askPassword("type the password to decrypt your secret key"+attemptStr+": ", nil)
+		if err != nil {
+			return "", err
+		}
+		sec, err := nip49.Decrypt(ncryptsec, password)
+		if err != nil {
+			continue
+		}
+		return sec, nil
+	}
+	return "", fmt.Errorf("couldn't decrypt private key")
+}
+
+func askPassword(msg string, shouldAskAgain func(answer string) bool) (string, error) {
+	config := &readline.Config{
+		Stdout:                 color.Error,
+		Prompt:                 color.YellowString(msg),
+		InterruptPrompt:        "^C",
+		DisableAutoSaveHistory: true,
+		EnableMask:             true,
+		MaskRune:               '*',
+	}
+
+	rl, err := readline.NewEx(config)
+	if err != nil {
+		return "", err
+	}
+
+	for {
+		answer, err := rl.Readline()
+		if err != nil {
+			return "", err
+		}
+		answer = strings.TrimSpace(answer)
+		if shouldAskAgain != nil && shouldAskAgain(answer) {
+			continue
+		}
+		return answer, err
+	}
+}