vpnem: VPN infrastructure with load-balanced multi-protocol nodesHEADmain

- Multi-protocol VPS nodes (VLESS-REALITY + Hysteria2 + SOCKS5)
- Smart load balancing via recommendation API
- Windows/Linux client (Go + Wails + sing-box)
- Server API with RealIP detection and connection tracking
- Auto-deployment via vpnui control plane
- Silent Windows installer with UAC elevation
- Load-based server recommendation (no sticky sessions)
- Best Server one-click connection workflow

1 files changed, 71 insertions, 0 deletions

diff --git a/internal/control/state.go b/internal/control/state.go
new file mode 100644
index 0000000..7fc7827
--- /dev/null
+++ b/internal/control/state.go
@@ -0,0 +1,71 @@
+package control
+
+import (
+	"encoding/json"
+	"errors"
+	"os"
+	"path/filepath"
+	"sort"
+	"time"
+)
+
+type NodeState struct {
+	NodeID            string          `json:"node_id"`
+	BootstrapStatus   string          `json:"bootstrap_status"`
+	LastBootstrapAt   *time.Time      `json:"last_bootstrap_at,omitempty"`
+	LastHealthCheckAt *time.Time      `json:"last_health_check_at,omitempty"`
+	LastDNSSyncAt     *time.Time      `json:"last_dns_sync_at,omitempty"`
+	PublicHost        string          `json:"public_host,omitempty"`
+	Services          []ServiceStatus `json:"services,omitempty"`
+	Metadata          map[string]any  `json:"metadata,omitempty"`
+}
+
+type ServiceStatus struct {
+	Type   string `json:"type"`
+	Status string `json:"status"`
+	Port   int    `json:"port"`
+}
+
+func LoadNodeState(dir, nodeID string) (*NodeState, error) {
+	data, err := os.ReadFile(filepath.Join(dir, nodeID+".json"))
+	if err != nil {
+		return nil, err
+	}
+
+	var state NodeState
+	if err := json.Unmarshal(data, &state); err != nil {
+		return nil, err
+	}
+	return &state, nil
+}
+
+func SaveNodeState(dir string, state NodeState) error {
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return err
+	}
+
+	sort.Slice(state.Services, func(i, j int) bool {
+		return state.Services[i].Type < state.Services[j].Type
+	})
+
+	data, err := json.MarshalIndent(state, "", "  ")
+	if err != nil {
+		return err
+	}
+	data = append(data, '\n')
+
+	tmpPath := filepath.Join(dir, state.NodeID+".json.tmp")
+	finalPath := filepath.Join(dir, state.NodeID+".json")
+	if err := os.WriteFile(tmpPath, data, 0o600); err != nil {
+		return err
+	}
+	return os.Rename(tmpPath, finalPath)
+}
+
+func DeleteNodeState(dir, nodeID string) error {
+	err := os.Remove(filepath.Join(dir, nodeID+".json"))
+	if errors.Is(err, os.ErrNotExist) {
+		return nil
+	}
+	return err
+}