feat: add persistent proxy profile management

internal/profile/store.go

@@ -0,0 +1,91 @@
+package profile
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+)
+
+type FileStore struct {
+	path string
+}
+
+func NewFileStore(path string) *FileStore {
+	return &FileStore{path: path}
+}
+
+func ConfigPath() (string, error) {
+	configDir, err := os.UserConfigDir()
+	if err != nil {
+		return "", fmt.Errorf("locate user configuration directory: %w", err)
+	}
+	return filepath.Join(configDir, "proxyctl", "profiles.json"), nil
+}
+
+func (s *FileStore) Load() (State, error) {
+	data, err := os.ReadFile(s.path)
+	if errors.Is(err, fs.ErrNotExist) {
+		return State{}, nil
+	}
+	if err != nil {
+		return State{}, fmt.Errorf("read Profile configuration: %w", err)
+	}
+	var state State
+	if err := json.Unmarshal(data, &state); err != nil {
+		return State{}, fmt.Errorf("parse Profile configuration: %w", err)
+	}
+	return state, nil
+}
+
+func (s *FileStore) Save(state State) error {
+	if err := os.MkdirAll(filepath.Dir(s.path), 0o700); err != nil {
+		return fmt.Errorf("create Profile configuration directory: %w", err)
+	}
+	if err := os.Chmod(filepath.Dir(s.path), 0o700); err != nil {
+		return fmt.Errorf("secure Profile configuration directory: %w", err)
+	}
+	data, err := json.MarshalIndent(state, "", "  ")
+	if err != nil {
+		return fmt.Errorf("encode Profile configuration: %w", err)
+	}
+	data = append(data, '\n')
+	temp, err := os.CreateTemp(filepath.Dir(s.path), ".profiles-*")
+	if err != nil {
+		return fmt.Errorf("create temporary Profile configuration: %w", err)
+	}
+	tempName := temp.Name()
+	defer os.Remove(tempName)
+	if err := temp.Chmod(0o600); err != nil {
+		temp.Close()
+		return fmt.Errorf("secure temporary Profile configuration: %w", err)
+	}
+	if _, err := temp.Write(data); err != nil {
+		temp.Close()
+		return fmt.Errorf("write temporary Profile configuration: %w", err)
+	}
+	if err := temp.Sync(); err != nil {
+		temp.Close()
+		return fmt.Errorf("sync temporary Profile configuration: %w", err)
+	}
+	if err := temp.Close(); err != nil {
+		return fmt.Errorf("close temporary Profile configuration: %w", err)
+	}
+	if err := os.Rename(tempName, s.path); err != nil {
+		return fmt.Errorf("replace Profile configuration: %w", err)
+	}
+	if err := os.Chmod(s.path, 0o600); err != nil {
+		return fmt.Errorf("secure Profile configuration: %w", err)
+	}
+	dir, err := os.Open(filepath.Dir(s.path))
+	if err == nil {
+		err = dir.Sync()
+		_ = dir.Close()
+	}
+	if err != nil {
+		return fmt.Errorf("sync Profile configuration directory: %w", err)
+	}
+	return nil
+}