From cf6c343fd5b421ae0c45cc0b10249f6660c1fa95 Mon Sep 17 00:00:00 2001
From: ayn2op <ayn2op@gmail.com>
Date: Fri, 21 Aug 2026 19:59:40 -0400
Subject: [PATCH] refactor: use encoding/json/v2

---
 internal/http/headers.go         |  2 +-
 internal/ui/login/qr/msg.go      | 87 ++++++++++++--------------------
 internal/ui/login/qr/msg_test.go | 30 +++++++++++
 3 files changed, 64 insertions(+), 55 deletions(-)
 create mode 100644 internal/ui/login/qr/msg_test.go

diff --git a/internal/http/headers.go b/internal/http/headers.go
index dc9ea3f..f04b5fb 100644
--- a/internal/http/headers.go
+++ b/internal/http/headers.go
@@ -2,7 +2,7 @@ package http
 
 import (
 	"encoding/base64"
-	"encoding/json"
+	json "encoding/json/v2"
 	"log/slog"
 	stdHttp "net/http"
 
diff --git a/internal/ui/login/qr/msg.go b/internal/ui/login/qr/msg.go
index b9ff282..483fd75 100644
--- a/internal/ui/login/qr/msg.go
+++ b/internal/ui/login/qr/msg.go
@@ -6,7 +6,7 @@ import (
 	"crypto/sha256"
 	"crypto/x509"
 	"encoding/base64"
-	"encoding/json"
+	json "encoding/json/v2"
 	"errors"
 	"strings"
 	"time"
@@ -90,60 +90,39 @@ func listen(conn *websocket.Conn) tview.Cmd {
 			return errMsg(err)
 		}
 
-		var payload struct {
-			Op string `json:"op"`
-		}
-		if err := json.Unmarshal(data, &payload); err != nil {
-			return errMsg(err)
-		}
+		return decodeMessage(data)
+	}
+}
 
-		switch payload.Op {
-		case "hello":
-			var payload struct {
-				HeartbeatInterval int `json:"heartbeat_interval"`
-				TimeoutMS         int `json:"timeout_ms"`
-			}
-			if err := json.Unmarshal(data, &payload); err != nil {
-				return errMsg(err)
-			}
-			return helloMsg{heartbeatInterval: payload.HeartbeatInterval, timeoutMS: payload.TimeoutMS}
-		case "nonce_proof":
-			var payload struct {
-				EncryptedNonce string `json:"encrypted_nonce"`
-			}
-			if err := json.Unmarshal(data, &payload); err != nil {
-				return errMsg(err)
-			}
-			return nonceProofMsg{encryptedNonce: payload.EncryptedNonce}
-		case "pending_remote_init":
-			var payload struct {
-				Fingerprint string `json:"fingerprint"`
-			}
-			if err := json.Unmarshal(data, &payload); err != nil {
-				return errMsg(err)
-			}
-			return pendingRemoteInitMsg{fingerprint: payload.Fingerprint}
-		case "pending_ticket":
-			var payload struct {
-				EncryptedUserPayload string `json:"encrypted_user_payload"`
-			}
-			if err := json.Unmarshal(data, &payload); err != nil {
-				return errMsg(err)
-			}
-			return pendingTicketMsg{encryptedUserPayload: payload.EncryptedUserPayload}
-		case "cancel":
-			return cancelMsg{}
-		case "pending_login":
-			var payload struct {
-				Ticket string `json:"ticket"`
-			}
-			if err := json.Unmarshal(data, &payload); err != nil {
-				return errMsg(err)
-			}
-			return pendingLoginMsg{ticket: payload.Ticket}
-		default:
-			return nil
-		}
+func decodeMessage(data []byte) tview.Msg {
+	var payload struct {
+		Op                   string `json:"op"`
+		HeartbeatInterval    int    `json:"heartbeat_interval"`
+		TimeoutMS            int    `json:"timeout_ms"`
+		EncryptedNonce       string `json:"encrypted_nonce"`
+		Fingerprint          string `json:"fingerprint"`
+		EncryptedUserPayload string `json:"encrypted_user_payload"`
+		Ticket               string `json:"ticket"`
+	}
+	if err := json.Unmarshal(data, &payload); err != nil {
+		return errMsg(err)
+	}
+
+	switch payload.Op {
+	case "hello":
+		return helloMsg{heartbeatInterval: payload.HeartbeatInterval, timeoutMS: payload.TimeoutMS}
+	case "nonce_proof":
+		return nonceProofMsg{encryptedNonce: payload.EncryptedNonce}
+	case "pending_remote_init":
+		return pendingRemoteInitMsg{fingerprint: payload.Fingerprint}
+	case "pending_ticket":
+		return pendingTicketMsg{encryptedUserPayload: payload.EncryptedUserPayload}
+	case "cancel":
+		return cancelMsg{}
+	case "pending_login":
+		return pendingLoginMsg{ticket: payload.Ticket}
+	default:
+		return nil
 	}
 }
 
diff --git a/internal/ui/login/qr/msg_test.go b/internal/ui/login/qr/msg_test.go
new file mode 100644
index 0000000..73fecfa
--- /dev/null
+++ b/internal/ui/login/qr/msg_test.go
@@ -0,0 +1,30 @@
+package qr
+
+import "testing"
+
+func TestDecodeMessage(t *testing.T) {
+	tests := []struct {
+		data string
+		want any
+	}{
+		{`{"op":"hello","heartbeat_interval":100,"timeout_ms":200}`, helloMsg{heartbeatInterval: 100, timeoutMS: 200}},
+		{`{"op":"nonce_proof","encrypted_nonce":"nonce"}`, nonceProofMsg{encryptedNonce: "nonce"}},
+		{`{"op":"pending_remote_init","fingerprint":"fingerprint"}`, pendingRemoteInitMsg{fingerprint: "fingerprint"}},
+		{`{"op":"pending_ticket","encrypted_user_payload":"payload"}`, pendingTicketMsg{encryptedUserPayload: "payload"}},
+		{`{"op":"cancel"}`, cancelMsg{}},
+		{`{"op":"pending_login","ticket":"ticket"}`, pendingLoginMsg{ticket: "ticket"}},
+		{`{"op":"unknown"}`, nil},
+	}
+
+	for _, test := range tests {
+		if got := decodeMessage([]byte(test.data)); got != test.want {
+			t.Errorf("decodeMessage(%s) = %#v, want %#v", test.data, got, test.want)
+		}
+	}
+}
+
+func TestDecodeMessageRejectsDuplicateNames(t *testing.T) {
+	if _, ok := decodeMessage([]byte(`{"op":"cancel","op":"hello"}`)).(errMsg); !ok {
+		t.Fatal("duplicate name was accepted")
+	}
+}