fix: exclude transient fields from unsaved changes detection

After ping status update, editing server form would incorrectly detect
unsaved changes. This fix excludes transient runtime fields (PingStatus,
PingLatency) and metadata fields from the comparison logic.

- Added struct tags to mark transient and metadata fields in domain.Server
- Updated serversDiffer() to skip fields based on struct tags
- Fixed goconst warnings by using existing status constants
- Added comprehensive tests for the change detection logic

Author: tan9

internal/adapters/ui/server_form.go

@@ -2039,22 +2039,30 @@ func (sf *ServerForm) serversDiffer(a, b domain.Server) bool {
 	valB := reflect.ValueOf(b)
 	typeA := valA.Type()
 
-	// Fields to skip during comparison (lazyssh metadata fields)
+	// Special fields to skip that don't have tags
 	skipFields := map[string]bool{
-		"Aliases":  true, // Computed field
-		"LastSeen": true, // Metadata field
-		"PinnedAt": true, // Metadata field
-		"SSHCount": true, // Metadata field
+		"Aliases": true, // Computed field (derived from Host)
 	}
 
 	// Iterate through all fields
 	for i := 0; i < valA.NumField(); i++ {
 		fieldA := valA.Field(i)
 		fieldB := valB.Field(i)
-		fieldName := typeA.Field(i).Name
+		field := typeA.Field(i)
+		fieldName := field.Name
 
-		// Skip unexported fields and metadata fields
-		if !fieldA.CanInterface() || skipFields[fieldName] {
+		// Skip unexported fields
+		if !fieldA.CanInterface() {
+			continue
+		}
+
+		// Skip special fields
+		if skipFields[fieldName] {
+			continue
+		}
+
+		// Check for lazyssh struct tags to skip metadata and transient fields
+		if tag := field.Tag.Get("lazyssh"); tag == "metadata" || tag == "transient" {
 			continue
 		}
 

internal/adapters/ui/server_form_test.go

@@ -0,0 +1,133 @@
+// Copyright 2025.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ui
+
+import (
+	"testing"
+	"time"
+
+	"github.com/Adembc/lazyssh/internal/core/domain"
+)
+
+func TestServersDifferIgnoresTransientFields(t *testing.T) {
+	sf := &ServerForm{}
+
+	// Create two servers with identical config but different transient fields
+	server1 := domain.Server{
+		Alias:       "test-server",
+		Host:        "example.com",
+		User:        "testuser",
+		Port:        22,
+		PingStatus:  "up",
+		PingLatency: 100 * time.Millisecond,
+		LastSeen:    time.Now(),
+		PinnedAt:    time.Now(),
+		SSHCount:    5,
+	}
+
+	server2 := domain.Server{
+		Alias:       "test-server",
+		Host:        "example.com",
+		User:        "testuser",
+		Port:        22,
+		PingStatus:  "down",                        // Different transient field
+		PingLatency: 200 * time.Millisecond,        // Different transient field
+		LastSeen:    time.Now().Add(1 * time.Hour), // Different metadata field
+		PinnedAt:    time.Now().Add(2 * time.Hour), // Different metadata field
+		SSHCount:    10,                            // Different metadata field
+	}
+
+	// Should not detect differences since only transient/metadata fields differ
+	if sf.serversDiffer(server1, server2) {
+		t.Error("serversDiffer should ignore transient and metadata fields")
+	}
+
+	// Now change a real config field
+	server2.Port = 2222
+
+	// Should detect the difference now
+	if !sf.serversDiffer(server1, server2) {
+		t.Error("serversDiffer should detect differences in non-transient fields")
+	}
+}
+
+func TestServersDifferDetectsRealChanges(t *testing.T) {
+	sf := &ServerForm{}
+
+	server1 := domain.Server{
+		Alias: "test-server",
+		Host:  "example.com",
+		User:  "testuser",
+		Port:  22,
+	}
+
+	testCases := []struct {
+		name   string
+		modify func(*domain.Server)
+		expect bool
+	}{
+		{
+			name:   "No changes",
+			modify: func(s *domain.Server) {},
+			expect: false,
+		},
+		{
+			name:   "Changed Host",
+			modify: func(s *domain.Server) { s.Host = "different.com" },
+			expect: true,
+		},
+		{
+			name:   "Changed User",
+			modify: func(s *domain.Server) { s.User = "otheruser" },
+			expect: true,
+		},
+		{
+			name:   "Changed Port",
+			modify: func(s *domain.Server) { s.Port = 2222 },
+			expect: true,
+		},
+		{
+			name:   "Added IdentityFile",
+			modify: func(s *domain.Server) { s.IdentityFiles = []string{"~/.ssh/id_rsa"} },
+			expect: true,
+		},
+		{
+			name:   "Changed ProxyJump",
+			modify: func(s *domain.Server) { s.ProxyJump = "jumphost" },
+			expect: true,
+		},
+		{
+			name:   "Changed only PingStatus (transient)",
+			modify: func(s *domain.Server) { s.PingStatus = "checking" },
+			expect: false,
+		},
+		{
+			name:   "Changed only LastSeen (metadata)",
+			modify: func(s *domain.Server) { s.LastSeen = time.Now().Add(1 * time.Hour) },
+			expect: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			server2 := server1 // Copy
+			tc.modify(&server2)
+			result := sf.serversDiffer(server1, server2)
+			if result != tc.expect {
+				t.Errorf("Expected %v but got %v for test case %s", tc.expect, result, tc.name)
+			}
+		})
+	}
+}

internal/adapters/ui/utils.go

@@ -89,7 +89,7 @@ func formatServerLine(s domain.Server, width int) (primary, secondary string) {
 	pingIndicator := ""
 	if s.PingStatus != "" {
 		switch s.PingStatus {
-		case "up":
+		case statusUp:
 			if s.PingLatency > 0 {
 				ms := s.PingLatency.Milliseconds()
 				var statusText string
@@ -106,9 +106,9 @@ func formatServerLine(s domain.Server, width int) (primary, secondary string) {
 			} else {
 				pingIndicator = "[#4AF626]● UP  [-]"
 			}
-		case "down":
+		case statusDown:
 			pingIndicator = "[#FF6B6B]● DOWN[-]"
-		case "checking":
+		case statusChecking:
 			pingIndicator = "[#FFB86C]● ... [-]"
 		}
 	}
@@ -133,11 +133,11 @@ func formatServerLine(s domain.Server, width int) (primary, secondary string) {
 			// Medium screen: show only dot
 			simplePingIndicator := ""
 			switch s.PingStatus {
-			case "up":
+			case statusUp:
 				simplePingIndicator = "[#4AF626]●[-]"
-			case "down":
+			case statusDown:
 				simplePingIndicator = "[#FF6B6B]●[-]"
-			case "checking":
+			case statusChecking:
 				simplePingIndicator = "[#FFB86C]●[-]"
 			}
 			paddingLen := width - mainTextLen - 1 // 1 for dot, no margin

internal/core/domain/server.go

@@ -24,11 +24,11 @@ type Server struct {
 	Port          int
 	IdentityFiles []string
 	Tags          []string
-	LastSeen      time.Time
-	PinnedAt      time.Time
-	SSHCount      int
-	PingStatus    string        // "up", "down", "checking", or ""
-	PingLatency   time.Duration // ping latency
+	LastSeen      time.Time     `lazyssh:"metadata"`
+	PinnedAt      time.Time     `lazyssh:"metadata"`
+	SSHCount      int           `lazyssh:"metadata"`
+	PingStatus    string        `lazyssh:"transient"` // "up", "down", "checking", or ""
+	PingLatency   time.Duration `lazyssh:"transient"` // ping latency
 
 	// Additional SSH config fields
 	// Connection and proxy settings