core: fix golang-ci lints and add a config

core/.golangci.yml

@@ -0,0 +1,77 @@
+linters-settings:
+  errcheck:
+    check-type-assertions: false
+    check-blank: false
+    exclude-functions:
+      # Cleanup/destroy operations
+      - (io.Closer).Close
+      - (*os.File).Close
+      - (net.Conn).Close
+      - (*net.Conn).Close
+      # Signal handling
+      - (*os.Process).Signal
+      - (*os.Process).Kill
+      # DBus cleanup
+      - (*github.com/godbus/dbus/v5.Conn).RemoveMatchSignal
+      - (*github.com/godbus/dbus/v5.Conn).RemoveSignal
+      # Encoding to network connections (if conn is bad, nothing we can do)
+      - (*encoding/json.Encoder).Encode
+      - (net.Conn).Write
+      # Command execution where failure is expected/ignored
+      - (*os/exec.Cmd).Run
+      - (*os/exec.Cmd).Start
+      # Flush operations
+      - (*bufio.Writer).Flush
+      # Scanning user input
+      - fmt.Scanln
+      - fmt.Scanf
+      # Parse operations where default value is acceptable
+      - fmt.Sscanf
+      # Flag operations
+      - (*github.com/spf13/pflag.FlagSet).MarkHidden
+      # Binary encoding to buffer (can't fail for basic types)
+      - binary.Write
+      # File operations in cleanup paths
+      - os.Rename
+      - os.Remove
+      - (*os.File).WriteString
+
+issues:
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - errcheck
+        - govet
+        - unused
+        - ineffassign
+        - staticcheck
+        - gosimple
+    # Exclude cleanup/teardown method calls from errcheck
+    - linters:
+        - errcheck
+      text: "Error return value of `.+\\.(Destroy|Release|Stop|Close|Roundtrip|Store)` is not checked"
+    # Exclude internal state update methods that are best-effort
+    - linters:
+        - errcheck
+      text: "Error return value of `[mb]\\.\\w*(update|initialize|recreate|acquire|enumerate|list|List|Ensure|refresh|Lock)\\w*` is not checked"
+    # Exclude SetMode on wayland power controls (best-effort)
+    - linters:
+        - errcheck
+      text: "Error return value of `.+\\.SetMode` is not checked"
+    # Exclude AddMatchSignal which is best-effort monitoring setup
+    - linters:
+        - errcheck
+      text: "Error return value of `.+\\.AddMatchSignal` is not checked"
+    # Exclude wayland pkg from errcheck and ineffassign (generated code patterns)
+    - linters:
+        - errcheck
+        - ineffassign
+      path: pkg/go-wayland/
+    # Exclude proto pkg from ineffassign (generated protocol code)
+    - linters:
+        - ineffassign
+      path: internal/proto/
+    # binary.Write to bytes.Buffer can't fail
+    - linters:
+        - errcheck
+      text: "Error return value of `binary\\.Write` is not checked"

core/cmd/dms/commands_greeter.go

@@ -11,6 +11,8 @@ import (
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/greeter"
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
 	"github.com/spf13/cobra"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 var greeterCmd = &cobra.Command{
@@ -258,7 +260,7 @@ func disableDisplayManager(dmName string) (bool, error) {
 		} else if shouldDisable {
 			return actionTaken, fmt.Errorf("%s is still in state '%s' after %s operation", dmName, enabledState, actionVerb)
 		} else {
-			fmt.Printf("  ✓ %s %s (now: %s)\n", strings.Title(actionVerb), dmName, enabledState)
+			fmt.Printf("  ✓ %s %s (now: %s)\n", cases.Title(language.English).String(actionVerb), dmName, enabledState)
 		}
 
 		actionTaken = true

core/internal/greeter/installer.go

@@ -367,7 +367,7 @@ func SyncDMSConfigs(dmsPath string, logFunc func(string), sudoPassword string) e
 			}
 		}
 
-		runSudoCmd(sudoPassword, "rm", "-f", link.target)
+		runSudoCmd(sudoPassword, "rm", "-f", link.target) //nolint:errcheck
 
 		if err := runSudoCmd(sudoPassword, "ln", "-sf", link.source, link.target); err != nil {
 			logFunc(fmt.Sprintf("⚠ Warning: Failed to create symlink for %s: %v", link.desc, err))

core/internal/keybinds/discovery.go

@@ -77,7 +77,7 @@ func (d *DiscoveryConfig) FindJSONFiles() ([]string, error) {
 func expandPath(path string) (string, error) {
 	expandedPath := os.ExpandEnv(path)
 
-	if filepath.HasPrefix(expandedPath, "~") {
+	if strings.HasPrefix(expandedPath, "~") {
 		home, err := os.UserHomeDir()
 		if err != nil {
 			return "", err

core/internal/keybinds/providers/jsonfile.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/keybinds"
 )
@@ -118,7 +119,7 @@ func (j *JSONFileProvider) GetCheatSheet() (*keybinds.CheatSheet, error) {
 func expandPath(path string) (string, error) {
 	expandedPath := os.ExpandEnv(path)
 
-	if filepath.HasPrefix(expandedPath, "~") {
+	if strings.HasPrefix(expandedPath, "~") {
 		home, err := os.UserHomeDir()
 		if err != nil {
 			return "", err

core/internal/log/filelogger.go

@@ -64,7 +64,7 @@ func (l *FileLogger) writeToFile(message string) {
 	redacted := l.redactPassword(message)
 	timestamp := time.Now().Format("15:04:05.000")
 
-	l.writer.WriteString(fmt.Sprintf("[%s] %s\n", timestamp, redacted))
+	l.writer.WriteString(fmt.Sprintf("[%s] %s\n", timestamp, redacted)) //nolint:errcheck
 	l.writer.Flush()
 }
 
@@ -93,7 +93,7 @@ func (l *FileLogger) Close() error {
 	defer l.mu.Unlock()
 
 	footer := fmt.Sprintf("\n=== DankInstall Log End ===\nCompleted: %s\n", time.Now().Format(time.RFC3339))
-	l.writer.WriteString(footer)
+	l.writer.WriteString(footer) //nolint:errcheck
 	l.writer.Flush()
 
 	if err := l.file.Sync(); err != nil {

core/internal/plugins/manager.go

@@ -93,7 +93,7 @@ func (m *Manager) Install(plugin Plugin) error {
 
 		if !repoExists {
 			if err := m.gitClient.PlainClone(repoPath, plugin.Repo); err != nil {
-				m.fs.RemoveAll(repoPath)
+				m.fs.RemoveAll(repoPath) //nolint:errcheck
 				return fmt.Errorf("failed to clone repository: %w", err)
 			}
 		} else {
@@ -130,7 +130,7 @@ func (m *Manager) Install(plugin Plugin) error {
 		}
 	} else {
 		if err := m.gitClient.PlainClone(pluginPath, plugin.Repo); err != nil {
-			m.fs.RemoveAll(pluginPath)
+			m.fs.RemoveAll(pluginPath) //nolint:errcheck
 			return fmt.Errorf("failed to clone plugin: %w", err)
 		}
 	}

core/internal/server/brightness/ddc.go

@@ -98,7 +98,7 @@ func (b *DDCBackend) probeDDCDevice(bus int) (*ddcDevice, error) {
 	}
 
 	dummy := make([]byte, 32)
-	syscall.Read(fd, dummy)
+	syscall.Read(fd, dummy) //nolint:errcheck
 
 	writebuf := []byte{0x00}
 	n, err := syscall.Write(fd, writebuf)

core/internal/server/brightness/logind.go

@@ -13,8 +13,7 @@ type DBusConn interface {
 }
 
 type LogindBackend struct {
-	conn     DBusConn
+	conn DBusConn
-	connOnce bool
 }
 
 func NewLogindBackend() (*LogindBackend, error) {

core/internal/server/cups/actions.go

@@ -251,14 +251,14 @@ func (m *Manager) CreatePrinter(name, deviceURI, ppd string, shared bool, errorP
 	}
 
 	if usedPkHelper {
-		m.pkHelper.PrinterSetEnabled(name, true)
+		m.pkHelper.PrinterSetEnabled(name, true)        //nolint:errcheck
-		m.pkHelper.PrinterSetAcceptJobs(name, true, "")
+		m.pkHelper.PrinterSetAcceptJobs(name, true, "") //nolint:errcheck
 	} else {
 		if err := m.client.ResumePrinter(name); isAuthError(err) && m.pkHelper != nil {
-			m.pkHelper.PrinterSetEnabled(name, true)
+			m.pkHelper.PrinterSetEnabled(name, true) //nolint:errcheck
 		}
 		if err := m.client.AcceptJobs(name); isAuthError(err) && m.pkHelper != nil {
-			m.pkHelper.PrinterSetAcceptJobs(name, true, "")
+			m.pkHelper.PrinterSetAcceptJobs(name, true, "") //nolint:errcheck
 		}
 	}
 

core/internal/server/network/agent_networkmanager.go

@@ -11,6 +11,8 @@ import (
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/errdefs"
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
 	"github.com/godbus/dbus/v5"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 const (
@@ -118,12 +120,6 @@ func (a *SecretAgent) GetSecrets(
 	log.Infof("[SecretAgent] GetSecrets called: path=%s, setting=%s, hints=%v, flags=%d",
 		path, settingName, hints, flags)
 
-	const (
-		NM_SECRET_AGENT_GET_SECRETS_FLAG_ALLOW_INTERACTION = 0x1
-		NM_SECRET_AGENT_GET_SECRETS_FLAG_REQUEST_NEW       = 0x2
-		NM_SECRET_AGENT_GET_SECRETS_FLAG_USER_REQUESTED    = 0x4
-	)
-
 	connType, displayName, vpnSvc := readConnTypeAndName(conn)
 	ssid := readSSID(conn)
 	fields := fieldsNeeded(settingName, hints)
@@ -378,7 +374,7 @@ func (a *SecretAgent) GetSecrets(
 	}
 
 	if settingName == "vpn" && a.backend != nil && (vpnUsername != "" || reply.Save) {
-		pw, _ := reply.Secrets["password"]
+		pw := reply.Secrets["password"]
 		a.backend.pendingVPNSaveMu.Lock()
 		a.backend.pendingVPNSave = &pendingVPNCredentials{
 			ConnectionPath: string(path),
@@ -620,11 +616,12 @@ func vpnFieldMeta(field, vpnService string) (label string, isSecret bool) {
 	case "private-key-password":
 		return "Private Key Password", true
 	}
+	titleCaser := cases.Title(language.English)
 	if strings.HasSuffix(field, "password") || strings.HasSuffix(field, "secret") ||
 		strings.HasSuffix(field, "pass") || strings.HasSuffix(field, "psk") {
-		return strings.Title(strings.ReplaceAll(field, "-", " ")), true
+		return titleCaser.String(strings.ReplaceAll(field, "-", " ")), true
 	}
-	return strings.Title(strings.ReplaceAll(field, "-", " ")), false
+	return titleCaser.String(strings.ReplaceAll(field, "-", " ")), false
 }
 
 func readVPNPasswordFlags(conn map[string]nmVariantMap, settingName string) uint32 {

core/internal/server/network/backend_hybrid_iwd_networkd.go

@@ -2,14 +2,12 @@ package network
 
 import (
 	"fmt"
-	"sync"
 )
 
 type HybridIwdNetworkdBackend struct {
 	wifi          *IWDBackend
 	l3            *SystemdNetworkdBackend
 	onStateChange func()
-	stateMutex    sync.RWMutex
 }
 
 func NewHybridIwdNetworkdBackend(w *IWDBackend, n *SystemdNetworkdBackend) (*HybridIwdNetworkdBackend, error) {
@@ -120,7 +118,7 @@ func (b *HybridIwdNetworkdBackend) ConnectWiFi(req ConnectionRequest) error {
 
 	ws, err := b.wifi.GetCurrentState()
 	if err == nil && ws.WiFiDevice != "" {
-		b.l3.EnsureDhcpUp(ws.WiFiDevice)
+		b.l3.EnsureDhcpUp(ws.WiFiDevice) //nolint:errcheck
 	}
 
 	return nil

core/internal/server/network/backend_iwd.go

@@ -5,6 +5,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
 	"github.com/godbus/dbus/v5"
 )
 
@@ -159,6 +160,7 @@ func (b *IWDBackend) OnUserCanceledPrompt() {
 
 	if cancelledSSID != "" {
 		if err := b.ForgetWiFiNetwork(cancelledSSID); err != nil {
+			log.Warnf("failed to forget cancelled WiFi network %s: %v", cancelledSSID, err)
 		}
 	}
 

core/internal/server/server.go

@@ -319,7 +319,6 @@ func handleConnection(conn net.Conn) {
 	capsData, _ := json.Marshal(caps)
 	conn.Write(capsData)
 	conn.Write([]byte("\n"))
-
 	scanner := bufio.NewScanner(conn)
 	for scanner.Scan() {
 		line := scanner.Bytes()

core/internal/tui/views_selection.go

@@ -72,10 +72,10 @@ func (m Model) viewSelectTerminal() string {
 	b.WriteString(title)
 	b.WriteString("\n\n")
 
-	options := []struct {
+	var options []struct {
 		name        string
 		description string
-	}{}
+	}
 
 	if m.osInfo != nil && m.osInfo.Distribution.ID == "gentoo" {
 		options = []struct {

core/internal/version/version.go

@@ -7,6 +7,8 @@ import (
 	"os/exec"
 	"path/filepath"
 	"strings"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
 )
 
 type VersionInfo struct {
@@ -33,7 +35,11 @@ func (d *DefaultVersionFetcher) GetCurrentVersion(dmsPath string) (string, error
 		if err != nil {
 			return "", err
 		}
-		defer os.Chdir(originalDir)
+		defer func() {
+			if err := os.Chdir(originalDir); err != nil {
+				log.Warnf("failed to change back to original directory: %v", err)
+			}
+		}()
 
 		if err := os.Chdir(dmsPath); err != nil {
 			return "", fmt.Errorf("failed to change to DMS directory: %w", err)
@@ -70,7 +76,11 @@ func (d *DefaultVersionFetcher) GetLatestVersion(dmsPath string) (string, error)
 		if err != nil {
 			return "", err
 		}
-		defer os.Chdir(originalDir)
+		defer func() {
+			if err := os.Chdir(originalDir); err != nil {
+				log.Warnf("failed to change back to original directory: %v", err)
+			}
+		}()
 
 		if err := os.Chdir(dmsPath); err != nil {
 			return "", fmt.Errorf("failed to change to DMS directory: %w", err)
@@ -85,7 +95,9 @@ func (d *DefaultVersionFetcher) GetLatestVersion(dmsPath string) (string, error)
 			if _, err := tagCmd.Output(); err == nil {
 				// Add timeout to git fetch to prevent hanging
 				fetchCmd := exec.Command("timeout", "5s", "git", "fetch", "origin", "--tags", "--quiet")
-				fetchCmd.Run()
+				if err := fetchCmd.Run(); err != nil {
+					log.Debugf("git fetch tags failed (continuing with local tags): %v", err)
+				}
 
 				latestTagCmd := exec.Command("git", "tag", "-l", "v*", "--sort=-version:refname")
 				latestTagOutput, err := latestTagCmd.Output()
@@ -109,7 +121,9 @@ func (d *DefaultVersionFetcher) GetLatestVersion(dmsPath string) (string, error)
 
 			// Add timeout to git fetch to prevent hanging
 			fetchCmd := exec.Command("timeout", "5s", "git", "fetch", "origin", currentBranch, "--quiet")
-			fetchCmd.Run()
+			if err := fetchCmd.Run(); err != nil {
+				log.Debugf("git fetch branch failed (continuing with local ref): %v", err)
+			}
 
 			remoteRevCmd := exec.Command("git", "rev-parse", "--short", fmt.Sprintf("origin/%s", currentBranch))
 			remoteRevOutput, err := remoteRevCmd.Output()
@@ -236,10 +250,10 @@ func CompareVersions(v1, v2 string) int {
 	for i := 0; i < maxLen; i++ {
 		var p1, p2 int
 		if i < len(parts1) {
-			fmt.Sscanf(parts1[i], "%d", &p1)
+			fmt.Sscanf(parts1[i], "%d", &p1) //nolint:errcheck
 		}
 		if i < len(parts2) {
-			fmt.Sscanf(parts2[i], "%d", &p2)
+			fmt.Sscanf(parts2[i], "%d", &p2) //nolint:errcheck
 		}
 
 		if p1 < p2 {

core/pkg/go-wayland/wayland/client/client.go

@@ -82,7 +82,6 @@ func (i *Display) Sync() (*Callback, error) {
 	PutUint32(_reqBuf[l:l+4], uint32(_reqBufLen<<16|opcode&0x0000ffff))
 	l += 4
 	PutUint32(_reqBuf[l:l+4], callback.ID())
-	l += 4
 	err := i.Context().WriteMsg(_reqBuf[:], nil)
 	return callback, err
 }
@@ -109,7 +108,6 @@ func (i *Display) GetRegistry() (*Registry, error) {
 	PutUint32(_reqBuf[l:l+4], uint32(_reqBufLen<<16|opcode&0x0000ffff))
 	l += 4
 	PutUint32(_reqBuf[l:l+4], registry.ID())
-	l += 4
 	err := i.Context().WriteMsg(_reqBuf[:], nil)
 	return registry, err
 }
@@ -223,7 +221,6 @@ func (i *Display) Dispatch(opcode uint32, fd int, data []byte) {
 		messageLen := PaddedLen(int(Uint32(data[l : l+4])))
 		l += 4
 		e.Message = String(data[l : l+messageLen])
-		l += messageLen
 
 		i.errorHandler(e)
 	case 1: